WorldWideScience

Sample records for cluster survey ix

  1. THE ACS SURVEY OF GALACTIC GLOBULAR CLUSTERS. IX. HORIZONTAL BRANCH MORPHOLOGY AND THE SECOND PARAMETER PHENOMENON

    International Nuclear Information System (INIS)

    Dotter, Aaron; Sarajedini, Ata; Anderson, Jay; Bedin, Luigi R.; Paust, Nathaniel; Reid, I. Neill; Aparicio, Antonio; MarIn-Franch, A.; Rosenberg, Alfred; Chaboyer, Brian; Majewski, Steven; Milone, Antonino; Piotto, Giampaolo; Siegel, Michael

    2010-01-01

    The horizontal branch (HB) morphology of globular clusters (GCs) is most strongly influenced by metallicity. The second parameter phenomenon, first described in the 1960s, acknowledges that metallicity alone is not enough to describe the HB morphology of all GCs. In particular, astronomers noticed that the outer Galactic halo contains GCs with redder HBs at a given metallicity than are found inside the solar circle. Thus, at least a second parameter was required to characterize HB morphology. While the term 'second parameter' has since come to be used in a broader context, its identity with respect to the original problem has not been conclusively determined. Here we analyze the median color difference between the HB and the red giant branch, hereafter denoted as Δ(V - I), measured from Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) photometry of 60 GCs within ∼20 kpc of the Galactic center. Analysis of this homogeneous data set reveals that, after the influence of metallicity has been removed from the data, the correlation between Δ(V - I) and age is stronger than that of any other parameter considered. Expanding the sample to include HST ACS and Wide Field Planetary Camera 2 photometry of the six most distant Galactic GCs lends additional support to the correlation between Δ(V - I) and age. This result is robust with respect to the adopted metallicity scale and the method of age determination, but must bear the caveat that high-quality, detailed abundance information is not available for a significant fraction of the sample. Furthermore, when a subset of GCs with similar metallicities and ages is considered, a correlation between Δ(V - I) and central luminosity density is exposed. With respect to the existence of GCs with anomalously red HBs at a given metallicity, we conclude that age is the second parameter and central density is most likely the third. Important problems related to HB morphology in GCs, notably multi-modal distributions

  2. The Munich Near-Infrared Cluster Survey - IX. Galaxy evolution to z ~ 2 from optically selected catalogues†‡

    Science.gov (United States)

    Feulner, Georg; Goranova, Yuliana; Hopp, Ulrich; Gabasch, Armin; Bender, Ralf; Botzler, Christine S.; Drory, Niv

    2007-06-01

    We present B-, R- and I-band-selected galaxy catalogues based on the Munich Near-Infrared Cluster Survey (MUNICS) which, together with the previously used K-selected sample, serve as an important probe of galaxy evolution in the redshift range 0 Karl-Schwarzschild Strasse 2, D-85748, Garching bei München, Germany.

  3. The Swift/BAT AGN Spectroscopic Survey. IX. The Clustering Environments of an Unbiased Sample of Local AGNs

    Science.gov (United States)

    Powell, M. C.; Cappelluti, N.; Urry, C. M.; Koss, M.; Finoguenov, A.; Ricci, C.; Trakhtenbrot, B.; Allevato, V.; Ajello, M.; Oh, K.; Schawinski, K.; Secrest, N.

    2018-05-01

    We characterize the environments of local accreting supermassive black holes by measuring the clustering of AGNs in the Swift/BAT Spectroscopic Survey (BASS). With 548 AGN in the redshift range 0.01 2MASS galaxies, and interpreting it via halo occupation distribution and subhalo-based models, we constrain the occupation statistics of the full sample, as well as in bins of absorbing column density and black hole mass. We find that AGNs tend to reside in galaxy group environments, in agreement with previous studies of AGNs throughout a large range of luminosity and redshift, and that on average they occupy their dark matter halos similar to inactive galaxies of comparable stellar mass. We also find evidence that obscured AGNs tend to reside in denser environments than unobscured AGNs, even when samples were matched in luminosity, redshift, stellar mass, and Eddington ratio. We show that this can be explained either by significantly different halo occupation distributions or statistically different host halo assembly histories. Lastly, we see that massive black holes are slightly more likely to reside in central galaxies than black holes of smaller mass.

  4. Cosmology with cluster surveys

    Indian Academy of Sciences (India)

    Abstract. Surveys of clusters of galaxies provide us with a powerful probe of the den- sity and nature of the dark energy. The red-shift distribution of detected clusters is highly sensitive to the dark energy equation of state parameter w. Upcoming Sunyaev–. Zel'dovich (SZ) surveys would provide us large yields of clusters to ...

  5. The H IX galaxy survey - II. H I kinematics of H I eXtreme galaxies

    Science.gov (United States)

    Lutz, K. A.; Kilborn, V. A.; Koribalski, B. S.; Catinella, B.; Józsa, G. I. G.; Wong, O. I.; Stevens, A. R. H.; Obreschkow, D.; Dénes, H.

    2018-05-01

    By analysing a sample of galaxies selected from the H I Parkes All Sky Survey (HIPASS) to contain more than 2.5 times their expected H I content based on their optical properties, we investigate what drives these H I eXtreme (H IX) galaxies to be so H I-rich. We model the H I kinematics with the Tilted Ring Fitting Code TiRiFiC and compare the observed H IX galaxies to a control sample of galaxies from HIPASS as well as simulated galaxies built with the semi-analytic model DARK SAGE. We find that (1) H I discs in H IX galaxies are more likely to be warped and more likely to host H I arms and tails than in the control galaxies, (2) the average H I and average stellar column density of H IX galaxies is comparable to the control sample, (3) H IX galaxies have higher H I and baryonic specific angular momenta than control galaxies, (4) most H IX galaxies live in higher spin haloes than most control galaxies. These results suggest that H IX galaxies are H I-rich because they can support more H I against gravitational instability due to their high specific angular momentum. The majority of the H IX galaxies inherits their high specific angular momentum from their halo. The H I content of H IX galaxies might be further increased by gas-rich minor mergers. This paper is based on data obtained with the Australia Telescope Compact Array through the large program C 2705.

  6. Studying dark energy with galaxy cluster surveys

    International Nuclear Information System (INIS)

    Mohr, Joseph J.; O'Shea, Brian; Evrard, August E.; Bialek, John; Haiman, Zoltan

    2003-01-01

    Galaxy cluster surveys provide a powerful means of studying the density and nature of the dark energy. The redshift distribution of detected clusters in a deep, large solid angle SZE or X-ray survey is highly sensitive to the dark energy equation of state. Accurate constraints at the 5% level on the dark energy equation of state require that systematic biases in the mass estimators must be controlled at better than the ∼10% level. Observed regularity in the cluster population and the availability of multiple, independent mass estimators suggests these precise measurements are possible. Using hydrodynamical simulations that include preheating, we show that the level of preheating required to explain local galaxy cluster structure has a dramatic effect on X-ray cluster surveys, but only a mild effect on SZE surveys. This suggests that SZE surveys may be optimal for cosmology while X-ray surveys are well suited for studies of the thermal history of the intracluster medium

  7. GASP. IX. Jellyfish galaxies in phase-space: an orbital study of intense ram-pressure stripping in clusters

    Science.gov (United States)

    Jaffé, Yara L.; Poggianti, Bianca M.; Moretti, Alessia; Gullieuszik, Marco; Smith, Rory; Vulcani, Benedetta; Fasano, Giovanni; Fritz, Jacopo; Tonnesen, Stephanie; Bettoni, Daniela; Hau, George; Biviano, Andrea; Bellhouse, Callum; McGee, Sean

    2018-06-01

    It is well known that galaxies falling into clusters can experience gas stripping due to ram pressure by the intra-cluster medium. The most spectacular examples are galaxies with extended tails of optically bright stripped material known as `jellyfish'. We use the first large homogeneous compilation of jellyfish galaxies in clusters from the WINGS and OmegaWINGS surveys, and follow-up MUSE observations from the GASP MUSE programme to investigate the orbital histories of jellyfish galaxies in clusters and reconstruct their stripping history through position versus velocity phase-space diagrams. We construct analytic models to define the regions in phase-space where ram-pressure stripping is at play. We then study the distribution of cluster galaxies in phase-space and find that jellyfish galaxies have on average higher peculiar velocities (and higher cluster velocity dispersion) than the overall population of cluster galaxies at all cluster-centric radii, which is indicative of recent infall into the cluster and radial orbits. In particular, the jellyfish galaxies with the longest gas tails reside very near the cluster cores (in projection) and are moving at very high speeds, which coincides with the conditions of the most intense ram pressure. We conclude that many of the jellyfish galaxies seen in clusters likely formed via fast (˜1-2 Gyr), incremental, outside-in ram-pressure stripping during first infall into the cluster in highly radial orbits.

  8. Synthesis and photochemical properties of a novel iron-sulfur-nitrosyl cluster derivatized with the pendant chromophore protoporphyrin IX.

    Science.gov (United States)

    Conrado, Christa L; Wecksler, Stephen; Egler, Christian; Magde, Douglas; Ford, Peter C

    2004-09-06

    The novel Roussin red-salt ester (PPIX-RSE) with a pendant porphyrin chromophore was prepared and investigated as a precursor for the photochemical generation of nitric oxide. PPIX-RSE has the general formula Fe(2)(NO)(4)[(mu-S,mu-S')P] (where (S,S')P is the bis(2-thiolatoethyl) diester of protoporphyrin IX. The photoexcitation of PPIX-RSE with 436- or 546-nm light in an aerated chloroform solution led to the photodecomposition of the cluster with the respective quantum yields (5.2 +/- 0.7) x 10(-4) and (2.5 +/- 0.5 x 10(-4)) and the concomitant release of NO. PPIX-RSE is a significantly more effective NO generator at longer wavelength excitation than are other Fe(2)(mu-SR)(2)(NO)(4) esters for which R is a simple alkyl group such as CH(3)CH(2)- because of the much higher absorptivity of the pendant PPIX chromophore at these wavelengths and a modestly higher quantum yield. Fluorescence intensity and lifetime data indicate that the photoexcited porphyrin of PPIX-RSE is largely quenched by the energy transfer to the Fe(2)S(2)(NO)(4) cluster's core. However, a small fraction of this emission is not quenched, and it is proposed that PPIX-RSE may exist in solution as two conformers.

  9. Planck early results. IX. XMM-Newton follow-up for validation of Planck cluster candidates

    DEFF Research Database (Denmark)

    Poutanen, T.; Natoli, P.; Polenta, G.

    2011-01-01

    We present the XMM-Newton follow-up for confirmation of Planck cluster candidates. Twenty-five candidates have been observed to date using snapshot (∼10 ks) exposures, ten as part of a pilot programme to sample a low range of signal-to-noise ratios (4

  10. Cluster cosmology with next-generation surveys.

    Science.gov (United States)

    Ascaso, B.

    2017-03-01

    The advent of next-generation surveys will provide a large number of cluster detections that will serve the basis for constraining cos mological parameters using cluster counts. The main two observational ingredients needed are the cluster selection function and the calibration of the mass-observable relation. In this talk, we present the methodology designed to obtain robust predictions of both ingredients based on realistic cosmological simulations mimicking the following next-generation surveys: J-PAS, LSST and Euclid. We display recent results on the selection functions for these mentioned surveys together with others coming from other next-generation surveys such as eROSITA, ACTpol and SPTpol. We notice that the optical and IR surveys will reach the lowest masses between 0.3surveys and introduce very preliminary results.

  11. THE BOLOCAM GALACTIC PLANE SURVEY. IX. DATA RELEASE 2 AND OUTER GALAXY EXTENSION

    Energy Technology Data Exchange (ETDEWEB)

    Ginsburg, Adam; Glenn, Jason; Ellsworth-Bowers, Timothy P.; Battersby, Cara; Bally, John; Stringfellow, Guy [CASA, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Rosolowsky, Erik [Department of Physics, 4-181 CCIS, University of Alberta, Edmonton, AB T6G 2E1 (Canada); Dunham, Miranda [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520 (United States); Merello, Manuel; Evans II, Neal J. [Department of Astronomy, The University of Texas, 2515 Speedway, Stop C1400 Austin, TX 78712-1205 (United States); Shirley, Yancy [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Aguirre, James, E-mail: Adam.Ginsburg@colorado.edu [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States)

    2013-10-01

    We present a re-reduction and expansion of the Bolocam Galactic Plane Survey (BGPS), first presented by Aguirre et al. and Rosolowsky et al. The BGPS is a 1.1 mm survey of dust emission in the Northern galactic plane, covering longitudes –10° < l < 90° and latitudes |b| < 0.°5 with a typical 1σ rms sensitivity of 30-100 mJy in a ∼33'' beam. Version 2 of the survey includes an additional ∼20 deg{sup 2} of coverage in the third and fourth quadrants and ∼2 deg{sup 2} in the first quadrant. The new data release has improved angular recovery, with complete recovery out to ∼80'' and partial recovery to ∼300'', and reduced negative bowls around bright sources resulting from the atmospheric subtraction process. We resolve the factor of 1.5 flux calibration offset between the v1.0 data release and other data sets and determine that there is no offset between v2.0 and other data sets. The v2.0 pointing accuracy is tested against other surveys and is demonstrated to be accurate and an improvement over v1.0. We present simulations and tests of the pipeline and its properties, including measurements of the pipeline's angular transfer function. The Bolocat cataloging tool was used to extract a new catalog, which includes 8594 sources, with 591 in the expanded regions. We have demonstrated that the Bolocat 40'' and 80'' apertures are accurate even in the presence of strong extended background emission. The number of sources is lower than in v1.0, but the amount of flux and area included in identified sources is larger.

  12. Panchromatic Hubble Andromeda Treasury. IX. A photometric survey of planetary nebulae in M31

    Energy Technology Data Exchange (ETDEWEB)

    Veyette, Mark J.; Williams, Benjamin F.; Dalcanton, Julianne J.; Balick, Bruce; Fouesneau, Morgan [Department of Astronomy, University of Washington, P.O. Box 351580, Seattle, WA 98195 (United States); Caldwell, Nelson [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Girardi, Léo [Osservatorio Astronomico di Padova—INAF, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Gordon, Karl D.; Kalirai, Jason [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Rosenfield, Philip [Department of Physics and Astronomy G. Galilei, University of Padova, Vicolo dell' Osservatorio 3, I-35122 Padova (Italy); Seth, Anil C., E-mail: mveyette@uw.edu [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States)

    2014-09-10

    We search the Hubble Space Telescope (HST) Advanced Camera for Surveys and Wide Field Camera 3 broadband imaging data from the Panchromatic Hubble Andromeda Treasury (PHAT) survey to identify detections of cataloged planetary nebulae (PNs). Of the 711 PNs currently in the literature within the PHAT footprint, we find 467 detected in the broadband. For these 467, we are able to refine their astrometric accuracy from ∼0.''3 to 0.''05. Using the resolution of the HST, we are able to show that 152 objects currently in the catalogs are definitively not PNs, and we show that 32 objects thought to be extended in ground-based images are actually point-like and therefore good PN candidates. We also find one PN candidate that is marginally resolved. If this is a PN, it is up to 0.7 pc in diameter. With our new photometric data, we develop a method of measuring the level of excitation in individual PNs by comparing broadband and narrowband imaging and describe the effects of excitation on a PN's photometric signature. Using the photometric properties of the known PNs in the PHAT catalogs, we search for more PNs, but do not find any new candidates, suggesting that ground-based emission-line surveys are complete in the PHAT footprint to F475W ≅ 24.

  13. THE MASSIVE DISTANT CLUSTERS OF WISE SURVEY: THE FIRST DISTANT GALAXY CLUSTER DISCOVERED BY WISE

    International Nuclear Information System (INIS)

    Gettings, Daniel P.; Gonzalez, Anthony H.; Mancone, Conor; Stanford, S. Adam; Eisenhardt, Peter R. M.; Stern, Daniel; Brodwin, Mark; Zeimann, Gregory R.; Masci, Frank J.; Papovich, Casey; Tanaka, Ichi; Wright, Edward L.

    2012-01-01

    We present spectroscopic confirmation of a z = 0.99 galaxy cluster discovered using data from the Wide-field Infrared Survey Explorer (WISE). This is the first z ∼ 1 cluster candidate from the Massive Distant Clusters of WISE Survey to be confirmed. It was selected as an overdensity of probable z ∼> 1 sources using a combination of WISE and Sloan Digital Sky Survey DR8 photometric catalogs. Deeper follow-up imaging data from Subaru and WIYN reveal the cluster to be a rich system of galaxies, and multi-object spectroscopic observations from Keck confirm five cluster members at z = 0.99. The detection and confirmation of this cluster represents a first step toward constructing a uniformly selected sample of distant, high-mass galaxy clusters over the full extragalactic sky using WISE data.

  14. Hierarchical modeling of cluster size in wildlife surveys

    Science.gov (United States)

    Royle, J. Andrew

    2008-01-01

    Clusters or groups of individuals are the fundamental unit of observation in many wildlife sampling problems, including aerial surveys of waterfowl, marine mammals, and ungulates. Explicit accounting of cluster size in models for estimating abundance is necessary because detection of individuals within clusters is not independent and detectability of clusters is likely to increase with cluster size. This induces a cluster size bias in which the average cluster size in the sample is larger than in the population at large. Thus, failure to account for the relationship between delectability and cluster size will tend to yield a positive bias in estimates of abundance or density. I describe a hierarchical modeling framework for accounting for cluster-size bias in animal sampling. The hierarchical model consists of models for the observation process conditional on the cluster size distribution and the cluster size distribution conditional on the total number of clusters. Optionally, a spatial model can be specified that describes variation in the total number of clusters per sample unit. Parameter estimation, model selection, and criticism may be carried out using conventional likelihood-based methods. An extension of the model is described for the situation where measurable covariates at the level of the sample unit are available. Several candidate models within the proposed class are evaluated for aerial survey data on mallard ducks (Anas platyrhynchos).

  15. Microbial community development in a dynamic gut model is reproducible, colon region specific, and selective for Bacteroidetes and Clostridium cluster IX.

    Science.gov (United States)

    Van den Abbeele, Pieter; Grootaert, Charlotte; Marzorati, Massimo; Possemiers, Sam; Verstraete, Willy; Gérard, Philippe; Rabot, Sylvie; Bruneau, Aurélia; El Aidy, Sahar; Derrien, Muriel; Zoetendal, Erwin; Kleerebezem, Michiel; Smidt, Hauke; Van de Wiele, Tom

    2010-08-01

    Dynamic, multicompartment in vitro gastrointestinal simulators are often used to monitor gut microbial dynamics and activity. These reactors need to harbor a microbial community that is stable upon inoculation, colon region specific, and relevant to in vivo conditions. Together with the reproducibility of the colonization process, these criteria are often overlooked when the modulatory properties from different treatments are compared. We therefore investigated the microbial colonization process in two identical simulators of the human intestinal microbial ecosystem (SHIME), simultaneously inoculated with the same human fecal microbiota with a high-resolution phylogenetic microarray: the human intestinal tract chip (HITChip). Following inoculation of the in vitro colon compartments, microbial community composition reached steady state after 2 weeks, whereas 3 weeks were required to reach functional stability. This dynamic colonization process was reproducible in both SHIME units and resulted in highly diverse microbial communities which were colon region specific, with the proximal regions harboring saccharolytic microbes (e.g., Bacteroides spp. and Eubacterium spp.) and the distal regions harboring mucin-degrading microbes (e.g., Akkermansia spp.). Importantly, the shift from an in vivo to an in vitro environment resulted in an increased Bacteroidetes/Firmicutes ratio, whereas Clostridium cluster IX (propionate producers) was enriched compared to clusters IV and XIVa (butyrate producers). This was supported by proportionally higher in vitro propionate concentrations. In conclusion, high-resolution analysis of in vitro-cultured gut microbiota offers new insight on the microbial colonization process and indicates the importance of digestive parameters that may be crucial in the development of new in vitro models.

  16. Global survey of star clusters in the Milky Way. VI. Age distribution and cluster formation history

    Science.gov (United States)

    Piskunov, A. E.; Just, A.; Kharchenko, N. V.; Berczik, P.; Scholz, R.-D.; Reffert, S.; Yen, S. X.

    2018-06-01

    Context. The all-sky Milky Way Star Clusters (MWSC) survey provides uniform and precise ages, along with other relevant parameters, for a wide variety of clusters in the extended solar neighbourhood. Aims: In this study we aim to construct the cluster age distribution, investigate its spatial variations, and discuss constraints on cluster formation scenarios of the Galactic disk during the last 5 Gyrs. Methods: Due to the spatial extent of the MWSC, we have considered spatial variations of the age distribution along galactocentric radius RG, and along Z-axis. For the analysis of the age distribution we used 2242 clusters, which all lie within roughly 2.5 kpc of the Sun. To connect the observed age distribution to the cluster formation history we built an analytical model based on simple assumptions on the cluster initial mass function and on the cluster mass-lifetime relation, fit it to the observations, and determined the parameters of the cluster formation law. Results: Comparison with the literature shows that earlier results strongly underestimated the number of evolved clusters with ages t ≳ 100 Myr. Recent studies based on all-sky catalogues agree better with our data, but still lack the oldest clusters with ages t ≳ 1 Gyr. We do not observe a strong variation in the age distribution along RG, though we find an enhanced fraction of older clusters (t > 1 Gyr) in the inner disk. In contrast, the distribution strongly varies along Z. The high altitude distribution practically does not contain clusters with t < 1 Gyr. With simple assumptions on the cluster formation history, the cluster initial mass function and the cluster lifetime we can reproduce the observations. The cluster formation rate and the cluster lifetime are strongly degenerate, which does not allow us to disentangle different formation scenarios. In all cases the cluster formation rate is strongly declining with time, and the cluster initial mass function is very shallow at the high mass end.

  17. LENSING NOISE IN MILLIMETER-WAVE GALAXY CLUSTER SURVEYS

    International Nuclear Information System (INIS)

    Hezaveh, Yashar; Vanderlinde, Keith; Holder, Gilbert; De Haan, Tijmen

    2013-01-01

    We study the effects of gravitational lensing by galaxy clusters of the background of dusty star-forming galaxies (DSFGs) and the cosmic microwave background (CMB), and examine the implications for Sunyaev-Zel'dovich-based (SZ) galaxy cluster surveys. At the locations of galaxy clusters, gravitational lensing modifies the probability distribution of the background flux of the DSFGs as well as the CMB. We find that, in the case of a single-frequency 150 GHz survey, lensing of DSFGs leads both to a slight increase (∼10%) in detected cluster number counts (due to a ∼50% increase in the variance of the DSFG background, and hence an increased Eddington bias) and a rare (occurring in ∼2% of clusters) 'filling-in' of SZ cluster signals by bright strongly lensed background sources. Lensing of the CMB leads to a ∼55% reduction in CMB power at the location of massive galaxy clusters in a spatially matched single-frequency filter, leading to a net decrease in detected cluster number counts. We find that the increase in DSFG power and decrease in CMB power due to lensing at cluster locations largely cancel, such that the net effect on cluster number counts for current SZ surveys is subdominant to Poisson errors

  18. Survey of quasi-free cluster knockout

    International Nuclear Information System (INIS)

    Roos, P.G.; Chant, N.S.

    1975-01-01

    The investigation of quasi-free knockout reactions has been proceeding for many years now, since the first experiments studying (p,2p) reactions on light nuclei. These experiments clearly showed the dominance of quasi-free proton knockout, and have provided information on the proton holes states in nuclei. From very early in the game people extended these studies to the knock-out of clusters, in an attempt to obtain nuclear structure information about clustering in nuclei. These cluster knockout reactions, excluding the nucleon knockout work, are examined. 20 figures, 16 references

  19. THE ACS NEARBY GALAXY SURVEY TREASURY. IX. CONSTRAINING ASYMPTOTIC GIANT BRANCH EVOLUTION WITH OLD METAL-POOR GALAXIES

    International Nuclear Information System (INIS)

    Girardi, Leo; Williams, Benjamin F.; Gilbert, Karoline M.; Rosenfield, Philip; Dalcanton, Julianne J.; Marigo, Paola; Boyer, Martha L.; Dolphin, Andrew; Weisz, Daniel R.; Skillman, Evan; Melbourne, Jason; Olsen, Knut A. G.; Seth, Anil C.

    2010-01-01

    In an attempt to constrain evolutionary models of the asymptotic giant branch (AGB) phase at the limit of low masses and low metallicities, we have examined the luminosity functions and number ratios between AGB and red giant branch (RGB) stars from a sample of resolved galaxies from the ACS Nearby Galaxy Survey Treasury. This database provides Hubble Space Telescope optical photometry together with maps of completeness, photometric errors, and star formation histories for dozens of galaxies within 4 Mpc. We select 12 galaxies characterized by predominantly metal-poor populations as indicated by a very steep and blue RGB, and which do not present any indication of recent star formation in their color-magnitude diagrams. Thousands of AGB stars brighter than the tip of the RGB (TRGB) are present in the sample (between 60 and 400 per galaxy), hence, the Poisson noise has little impact in our measurements of the AGB/RGB ratio. We model the photometric data with a few sets of thermally pulsing AGB (TP-AGB) evolutionary models with different prescriptions for the mass loss. This technique allows us to set stringent constraints on the TP-AGB models of low-mass, metal-poor stars (with M sun , [Fe/H]∼ sun . This is also in good agreement with recent observations of white dwarf masses in the M4 old globular cluster. These constraints can be added to those already derived from Magellanic Cloud star clusters as important mileposts in the arduous process of calibrating AGB evolutionary models.

  20. THE SWIFT AGN AND CLUSTER SURVEY. II. CLUSTER CONFIRMATION WITH SDSS DATA

    International Nuclear Information System (INIS)

    Griffin, Rhiannon D.; Dai, Xinyu; Kochanek, Christopher S.; Bregman, Joel N.

    2016-01-01

    We study 203 (of 442) Swift AGN and Cluster Survey extended X-ray sources located in the SDSS DR8 footprint to search for galaxy over-densities in three-dimensional space using SDSS galaxy photometric redshifts and positions near the Swift cluster candidates. We find 104 Swift clusters with a >3σ galaxy over-density. The remaining targets are potentially located at higher redshifts and require deeper optical follow-up observations for confirmation as galaxy clusters. We present a series of cluster properties including the redshift, brightest cluster galaxy (BCG) magnitude, BCG-to-X-ray center offset, optical richness, and X-ray luminosity. We also detect red sequences in ∼85% of the 104 confirmed clusters. The X-ray luminosity and optical richness for the SDSS confirmed Swift clusters are correlated and follow previously established relations. The distribution of the separations between the X-ray centroids and the most likely BCG is also consistent with expectation. We compare the observed redshift distribution of the sample with a theoretical model, and find that our sample is complete for z ≲ 0.3 and is still 80% complete up to z ≃ 0.4, consistent with the SDSS survey depth. These analysis results suggest that our Swift cluster selection algorithm has yielded a statistically well-defined cluster sample for further study of cluster evolution and cosmology. We also match our SDSS confirmed Swift clusters to existing cluster catalogs, and find 42, 23, and 1 matches in optical, X-ray, and Sunyaev–Zel’dovich catalogs, respectively, and so the majority of these clusters are new detections

  1. Optical study of the DAFT/FADA galaxy cluster survey

    Science.gov (United States)

    Martinet, N.; Durret, F.; Clowe, D.; Adami, C.

    2013-11-01

    DAFT/FADA (Dark energy American French Team) is a large survey of ˜90 high redshift (0.42×10^{14} M_{⊙}) clusters with HST weak lensing oriented data, plus BVRIZJ 4m ground based follow up to compute photometric redshifts. The main goals of this survey are to constrain dark energy parameters using weak lensing tomography and to study a large homogeneous sample of high redshift massive clusters. We will briefly review the latest results of this optical survey, focusing on two ongoing works: the calculation of galaxy luminosity functions from photometric redshift catalogs and the weak lensing analysis of ground based data.

  2. Cosmological analysis of galaxy clusters surveys in X-rays

    International Nuclear Information System (INIS)

    Clerc, N.

    2012-01-01

    Clusters of galaxies are the most massive objects in equilibrium in our Universe. Their study allows to test cosmological scenarios of structure formation with precision, bringing constraints complementary to those stemming from the cosmological background radiation, supernovae or galaxies. They are identified through the X-ray emission of their heated gas, thus facilitating their mapping at different epochs of the Universe. This report presents two surveys of galaxy clusters detected in X-rays and puts forward a method for their cosmological interpretation. Thanks to its multi-wavelength coverage extending over 10 sq. deg. and after one decade of expertise, the XMM-LSS allows a systematic census of clusters in a large volume of the Universe. In the framework of this survey, the first part of this report describes the techniques developed to the purpose of characterizing the detected objects. A particular emphasis is placed on the most distant ones (z ≥ 1) through the complementarity of observations in X-ray, optical and infrared bands. Then the X-CLASS survey is fully described. Based on XMM archival data, it provides a new catalogue of 800 clusters detected in X-rays. A cosmological analysis of this survey is performed thanks to 'CR-HR' diagrams. This new method self-consistently includes selection effects and scaling relations and provides a means to bypass the computation of individual cluster masses. Propositions are made for applying this method to future surveys as XMM-XXL and eRosita. (author) [fr

  3. The C4 clustering algorithm: Clusters of galaxies in the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Christopher J.; Nichol, Robert; Reichart, Dan; Wechsler, Risa H.; Evrard, August; Annis, James; McKay, Timothy; Bahcall, Neta; Bernardi, Mariangela; Boehringer,; Connolly, Andrew; Goto, Tomo; Kniazev, Alexie; Lamb, Donald; Postman, Marc; Schneider, Donald; Sheth, Ravi; Voges, Wolfgang; /Cerro-Tololo InterAmerican Obs. /Portsmouth U.,

    2005-03-01

    We present the ''C4 Cluster Catalog'', a new sample of 748 clusters of galaxies identified in the spectroscopic sample of the Second Data Release (DR2) of the Sloan Digital Sky Survey (SDSS). The C4 cluster-finding algorithm identifies clusters as overdensities in a seven-dimensional position and color space, thus minimizing projection effects that have plagued previous optical cluster selection. The present C4 catalog covers {approx}2600 square degrees of sky and ranges in redshift from z = 0.02 to z = 0.17. The mean cluster membership is 36 galaxies (with redshifts) brighter than r = 17.7, but the catalog includes a range of systems, from groups containing 10 members to massive clusters with over 200 cluster members with redshifts. The catalog provides a large number of measured cluster properties including sky location, mean redshift, galaxy membership, summed r-band optical luminosity (L{sub r}), velocity dispersion, as well as quantitative measures of substructure and the surrounding large-scale environment. We use new, multi-color mock SDSS galaxy catalogs, empirically constructed from the {Lambda}CDM Hubble Volume (HV) Sky Survey output, to investigate the sensitivity of the C4 catalog to the various algorithm parameters (detection threshold, choice of passbands and search aperture), as well as to quantify the purity and completeness of the C4 cluster catalog. These mock catalogs indicate that the C4 catalog is {approx_equal}90% complete and 95% pure above M{sub 200} = 1 x 10{sup 14} h{sup -1}M{sub {circle_dot}} and within 0.03 {le} z {le} 0.12. Using the SDSS DR2 data, we show that the C4 algorithm finds 98% of X-ray identified clusters and 90% of Abell clusters within 0.03 {le} z {le} 0.12. Using the mock galaxy catalogs and the full HV dark matter simulations, we show that the L{sub r} of a cluster is a more robust estimator of the halo mass (M{sub 200}) than the galaxy line-of-sight velocity dispersion or the richness of the cluster

  4. Title IX Resource Guide

    Science.gov (United States)

    Office for Civil Rights, US Department of Education, 2015

    2015-01-01

    Title IX of the Education Amendments of 1972 (Title IX) prohibits discrimination based on sex in education programs and activities in federally funded schools at all levels. If any part of a school district or college receives any Federal funds for any purpose, all of the operations of the district or college are covered by Title IX. The essence…

  5. Hα star formation rates of z > 1 galaxy clusters in the IRAC shallow cluster survey

    International Nuclear Information System (INIS)

    Zeimann, Gregory R.; Stanford, S. A.; Brodwin, Mark; Gonzalez, Anthony H.; Mancone, Conor; Snyder, Gregory F.; Stern, Daniel; Eisenhardt, Peter; Dey, Arjun; Moustakas, John

    2013-01-01

    We present Hubble Space Telescope near-IR spectroscopy for 18 galaxy clusters at 1.0 Cluster Survey. We use Wide Field Camera 3 grism data to spectroscopically identify Hα emitters in both the cores of galaxy clusters as well as in field galaxies. We find a large cluster-to-cluster scatter in the star formation rates within a projected radius of 500 kpc, and many of our clusters (∼60%) have significant levels of star formation within a projected radius of 200 kpc. A stacking analysis reveals that dust reddening in these star-forming galaxies is positively correlated with stellar mass and may be higher in the field than the cluster at a fixed stellar mass. This may indicate a lower amount of gas in star-forming cluster galaxies than in the field population. Also, Hα equivalent widths of star-forming galaxies in the cluster environment are still suppressed below the level of the field. This suppression is most significant for lower mass galaxies (log M * < 10.0 M ☉ ). We therefore conclude that environmental effects are still important at 1.0 clusters with log M * ≲ 10.0 M ☉ .

  6. The clustering of quasars from an objective-prism survey

    International Nuclear Information System (INIS)

    Webster, A.

    1982-01-01

    The positions and redshifts of 108 quasars from the Cerro Tololo objective-prism survey are subjected to Fourier Power Spectrum Analysis in a search for clustering in their spatial distribution. It is found that, on the whole, these quasars are not clustered but are scattered in space independently at random. The sole exception is a group of four quasars at z = 0.37 which has a low probability of being a chance event and which, with a size of about 100 Mpc, may therefore be the largest known structure in the Universe. The conclusions disagree with Arp's analysis of this catalogue: his 'clouds of quasars' ejected by certain low-redshift galaxies, for example, are attributable to sensitivity variations among the different plates of the survey. It is shown that analysis of deeper surveys is likely to show up quasar clusters even at high redshift, and could therefore provide a useful new cosmological probe. (author)

  7. The Extended Northern ROSAT Galaxy Cluster Survey (NORAS II). I. Survey Construction and First Results

    Energy Technology Data Exchange (ETDEWEB)

    Böhringer, Hans; Chon, Gayoung; Trümper, Joachim [Max-Planck-Institut für Extraterrestrische Physik, D-85748 Garching (Germany); Retzlaff, Jörg [ESO, D-85748 Garching (Germany); Meisenheimer, Klaus [Max-Planck-Institut für Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Schartel, Norbert [ESAC, Camino Bajo del Castillo, Villanueva de la Cañada, E-28692 Madrid (Spain)

    2017-05-01

    As the largest, clearly defined building blocks of our universe, galaxy clusters are interesting astrophysical laboratories and important probes for cosmology. X-ray surveys for galaxy clusters provide one of the best ways to characterize the population of galaxy clusters. We provide a description of the construction of the NORAS II galaxy cluster survey based on X-ray data from the northern part of the ROSAT All-Sky Survey. NORAS II extends the NORAS survey down to a flux limit of 1.8 × 10{sup −12} erg s{sup −1} cm{sup −2} (0.1–2.4 keV), increasing the sample size by about a factor of two. The NORAS II cluster survey now reaches the same quality and depth as its counterpart, the southern REFLEX II survey, allowing us to combine the two complementary surveys. The paper provides information on the determination of the cluster X-ray parameters, the identification process of the X-ray sources, the statistics of the survey, and the construction of the survey selection function, which we provide in numerical format. Currently NORAS II contains 860 clusters with a median redshift of z  = 0.102. We provide a number of statistical functions, including the log N –log S and the X-ray luminosity function and compare these to the results from the complementary REFLEX II survey. Using the NORAS II sample to constrain the cosmological parameters, σ {sub 8} and Ω{sub m}, yields results perfectly consistent with those of REFLEX II. Overall, the results show that the two hemisphere samples, NORAS II and REFLEX II, can be combined without problems into an all-sky sample, just excluding the zone of avoidance.

  8. The Extended Northern ROSAT Galaxy Cluster Survey (NORAS II). I. Survey Construction and First Results

    International Nuclear Information System (INIS)

    Böhringer, Hans; Chon, Gayoung; Trümper, Joachim; Retzlaff, Jörg; Meisenheimer, Klaus; Schartel, Norbert

    2017-01-01

    As the largest, clearly defined building blocks of our universe, galaxy clusters are interesting astrophysical laboratories and important probes for cosmology. X-ray surveys for galaxy clusters provide one of the best ways to characterize the population of galaxy clusters. We provide a description of the construction of the NORAS II galaxy cluster survey based on X-ray data from the northern part of the ROSAT All-Sky Survey. NORAS II extends the NORAS survey down to a flux limit of 1.8 × 10 −12 erg s −1 cm −2 (0.1–2.4 keV), increasing the sample size by about a factor of two. The NORAS II cluster survey now reaches the same quality and depth as its counterpart, the southern REFLEX II survey, allowing us to combine the two complementary surveys. The paper provides information on the determination of the cluster X-ray parameters, the identification process of the X-ray sources, the statistics of the survey, and the construction of the survey selection function, which we provide in numerical format. Currently NORAS II contains 860 clusters with a median redshift of z  = 0.102. We provide a number of statistical functions, including the log N –log S and the X-ray luminosity function and compare these to the results from the complementary REFLEX II survey. Using the NORAS II sample to constrain the cosmological parameters, σ 8 and Ω m , yields results perfectly consistent with those of REFLEX II. Overall, the results show that the two hemisphere samples, NORAS II and REFLEX II, can be combined without problems into an all-sky sample, just excluding the zone of avoidance.

  9. Optimising cluster survey design for planning schistosomiasis preventive chemotherapy.

    Directory of Open Access Journals (Sweden)

    Sarah C L Knowles

    2017-05-01

    Full Text Available The cornerstone of current schistosomiasis control programmes is delivery of praziquantel to at-risk populations. Such preventive chemotherapy requires accurate information on the geographic distribution of infection, yet the performance of alternative survey designs for estimating prevalence and converting this into treatment decisions has not been thoroughly evaluated.We used baseline schistosomiasis mapping surveys from three countries (Malawi, Côte d'Ivoire and Liberia to generate spatially realistic gold standard datasets, against which we tested alternative two-stage cluster survey designs. We assessed how sampling different numbers of schools per district (2-20 and children per school (10-50 influences the accuracy of prevalence estimates and treatment class assignment, and we compared survey cost-efficiency using data from Malawi. Due to the focal nature of schistosomiasis, up to 53% simulated surveys involving 2-5 schools per district failed to detect schistosomiasis in low endemicity areas (1-10% prevalence. Increasing the number of schools surveyed per district improved treatment class assignment far more than increasing the number of children sampled per school. For Malawi, surveys of 15 schools per district and 20-30 children per school reliably detected endemic schistosomiasis and maximised cost-efficiency. In sensitivity analyses where treatment costs and the country considered were varied, optimal survey size was remarkably consistent, with cost-efficiency maximised at 15-20 schools per district.Among two-stage cluster surveys for schistosomiasis, our simulations indicated that surveying 15-20 schools per district and 20-30 children per school optimised cost-efficiency and minimised the risk of under-treatment, with surveys involving more schools of greater cost-efficiency as treatment costs rose.

  10. RELICS: Strong Lens Models for Five Galaxy Clusters from the Reionization Lensing Cluster Survey

    Science.gov (United States)

    Cerny, Catherine; Sharon, Keren; Andrade-Santos, Felipe; Avila, Roberto J.; Bradač, Maruša; Bradley, Larry D.; Carrasco, Daniela; Coe, Dan; Czakon, Nicole G.; Dawson, William A.; Frye, Brenda L.; Hoag, Austin; Huang, Kuang-Han; Johnson, Traci L.; Jones, Christine; Lam, Daniel; Lovisari, Lorenzo; Mainali, Ramesh; Oesch, Pascal A.; Ogaz, Sara; Past, Matthew; Paterno-Mahler, Rachel; Peterson, Avery; Riess, Adam G.; Rodney, Steven A.; Ryan, Russell E.; Salmon, Brett; Sendra-Server, Irene; Stark, Daniel P.; Strolger, Louis-Gregory; Trenti, Michele; Umetsu, Keiichi; Vulcani, Benedetta; Zitrin, Adi

    2018-06-01

    Strong gravitational lensing by galaxy clusters magnifies background galaxies, enhancing our ability to discover statistically significant samples of galaxies at {\\boldsymbol{z}}> 6, in order to constrain the high-redshift galaxy luminosity functions. Here, we present the first five lens models out of the Reionization Lensing Cluster Survey (RELICS) Hubble Treasury Program, based on new HST WFC3/IR and ACS imaging of the clusters RXC J0142.9+4438, Abell 2537, Abell 2163, RXC J2211.7–0349, and ACT-CLJ0102–49151. The derived lensing magnification is essential for estimating the intrinsic properties of high-redshift galaxy candidates, and properly accounting for the survey volume. We report on new spectroscopic redshifts of multiply imaged lensed galaxies behind these clusters, which are used as constraints, and detail our strategy to reduce systematic uncertainties due to lack of spectroscopic information. In addition, we quantify the uncertainty on the lensing magnification due to statistical and systematic errors related to the lens modeling process, and find that in all but one cluster, the magnification is constrained to better than 20% in at least 80% of the field of view, including statistical and systematic uncertainties. The five clusters presented in this paper span the range of masses and redshifts of the clusters in the RELICS program. We find that they exhibit similar strong lensing efficiencies to the clusters targeted by the Hubble Frontier Fields within the WFC3/IR field of view. Outputs of the lens models are made available to the community through the Mikulski Archive for Space Telescopes.

  11. New Galactic star clusters discovered in the VVV survey

    Science.gov (United States)

    Borissova, J.; Bonatto, C.; Kurtev, R.; Clarke, J. R. A.; Peñaloza, F.; Sale, S. E.; Minniti, D.; Alonso-García, J.; Artigau, E.; Barbá, R.; Bica, E.; Baume, G. L.; Catelan, M.; Chenè, A. N.; Dias, B.; Folkes, S. L.; Froebrich, D.; Geisler, D.; de Grijs, R.; Hanson, M. M.; Hempel, M.; Ivanov, V. D.; Kumar, M. S. N.; Lucas, P.; Mauro, F.; Moni Bidin, C.; Rejkuba, M.; Saito, R. K.; Tamura, M.; Toledo, I.

    2011-08-01

    Context. VISTA Variables in the Vía Láctea (VVV) is one of the six ESO Public Surveys operating on the new 4-m Visible and Infrared Survey Telescope for Astronomy (VISTA). VVV is scanning the Milky Way bulge and an adjacent section of the disk, where star formation activity is high. One of the principal goals of the VVV Survey is to find new star clusters of differentages. Aims: In order to trace the early epochs of star cluster formation we concentrated our search in the directions to those of known star formation regions, masers, radio, and infrared sources. Methods: The disk area covered by VVV was visually inspected using the pipeline processed and calibrated KS-band tile images for stellar overdensities. Subsequently, we examined the composite JHKS and ZJKS color images of each candidate. PSF photometry of 15 × 15 arcmin fields centered on the candidates was then performed on the Cambridge Astronomy Survey Unit reduced images. After statistical field-star decontamination, color-magnitude and color-color diagrams were constructed and analyzed. Results: We report the discovery of 96 new infrared open clusters and stellar groups. Most of the new cluster candidates are faint and compact (with small angular sizes), highly reddened, and younger than 5 Myr. For relatively well populated cluster candidates we derived their fundamental parameters such as reddening, distance, and age by fitting the solar-metallicity Padova isochrones to the color-magnitude diagrams. Based on observations gathered with VIRCAM, VISTA of the ESO as part of observing programs 172.B-2002Appendix A is available in electronic form at http://www.aanda.orgTable 1 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/532/A131

  12. AMICO: optimized detection of galaxy clusters in photometric surveys

    Science.gov (United States)

    Bellagamba, Fabio; Roncarelli, Mauro; Maturi, Matteo; Moscardini, Lauro

    2018-02-01

    We present Adaptive Matched Identifier of Clustered Objects (AMICO), a new algorithm for the detection of galaxy clusters in photometric surveys. AMICO is based on the Optimal Filtering technique, which allows to maximize the signal-to-noise ratio (S/N) of the clusters. In this work, we focus on the new iterative approach to the extraction of cluster candidates from the map produced by the filter. In particular, we provide a definition of membership probability for the galaxies close to any cluster candidate, which allows us to remove its imprint from the map, allowing the detection of smaller structures. As demonstrated in our tests, this method allows the deblending of close-by and aligned structures in more than 50 per cent of the cases for objects at radial distance equal to 0.5 × R200 or redshift distance equal to 2 × σz, being σz the typical uncertainty of photometric redshifts. Running AMICO on mocks derived from N-body simulations and semi-analytical modelling of the galaxy evolution, we obtain a consistent mass-amplitude relation through the redshift range of 0.3 slope of ∼0.55 and a logarithmic scatter of ∼0.14. The fraction of false detections is steeply decreasing with S/N and negligible at S/N > 5.

  13. The HectoMAP Cluster Survey. I. redMaPPer Clusters

    Science.gov (United States)

    Sohn, Jubee; Geller, Margaret J.; Rines, Kenneth J.; Hwang, Ho Seong; Utsumi, Yousuke; Diaferio, Antonaldo

    2018-04-01

    We use the dense HectoMAP redshift survey to explore the properties of 104 redMaPPer cluster candidates. The redMaPPer systems in HectoMAP cover the full range of richness and redshift (0.08 systems included in the Subaru/Hyper Suprime-Cam public data release are bona fide clusters. The median number of spectroscopic members per cluster is ∼20. We include redshifts of 3547 member candidates listed in the redMaPPer catalog whether they are cluster members or not. We evaluate the redMaPPer membership probability spectroscopically. The purity (number of real systems) in redMaPPer exceeds 90% even at the lowest richness. Three massive galaxy clusters (M ∼ 2 × 1013 M ⊙) associated with X-ray emission in the HectoMAP region are not included in the public redMaPPer catalog with λ rich > 20, because they lie outside the cuts for this catalog.

  14. The next generation Virgo cluster survey. VIII. The spatial distribution of globular clusters in the Virgo cluster

    Energy Technology Data Exchange (ETDEWEB)

    Durrell, Patrick R.; Accetta, Katharine [Department of Physics and Astronomy, Youngstown State University, Youngstown, OH 44555 (United States); Côté, Patrick; Blakeslee, John P.; Ferrarese, Laura; McConnachie, Alan; Gwyn, Stephen [Herzberg Astronomy and Astrophysics, National Research Council, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Peng, Eric W.; Zhang, Hongxin [Department of Astronomy, Peking University, Beijing 100871 (China); Mihos, J. Christopher [Department of Astronomy, Case Western Reserve University, Cleveland, OH 44106 (United States); Puzia, Thomas H.; Jordán, Andrés [Institute of Astrophysics, Pontificia Universidad Catolica, Av. Vicu' a Mackenna 4860, Macul 7820436, Santiago (Chile); Lançon, Ariane [Observatoire astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l' Université, F-67000 Strasbourg (France); Liu, Chengze [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Cuillandre, Jean-Charles [Canada-France-Hawaii Telescope Corporation, Kamuela, HI 96743 (United States); Boissier, Samuel; Boselli, Alessandro [Aix Marseille Université, CNRS, LAM (Laboratoire d' Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France); Courteau, Stéphane [Department of Physics, Engineering Physics and Astronomy, Queen' s University, Kingston, ON K7L 3N6 (Canada); Duc, Pierre-Alain [AIM Paris Saclay, CNRS/INSU, CEA/Irfu, Université Paris Diderot, Orme des Merisiers, F-91191 Gif sur Yvette cedex (France); Emsellem, Eric [Université de Lyon 1, CRAL, Observatoire de Lyon, 9 av. Charles André, F-69230 Saint-Genis Laval (France); CNRS, UMR 5574, ENS de Lyon (France); and others

    2014-10-20

    We report on a large-scale study of the distribution of globular clusters (GCs) throughout the Virgo cluster, based on photometry from the Next Generation Virgo Cluster Survey (NGVS), a large imaging survey covering Virgo's primary subclusters (Virgo A = M87 and Virgo B = M49) out to their virial radii. Using the g{sub o}{sup ′}, (g' – i') {sub o} color-magnitude diagram of unresolved and marginally resolved sources within the NGVS, we have constructed two-dimensional maps of the (irregular) GC distribution over 100 deg{sup 2} to a depth of g{sub o}{sup ′} = 24. We present the clearest evidence to date showing the difference in concentration between red and blue GCs over the full extent of the cluster, where the red (more metal-rich) GCs are largely located around the massive early-type galaxies in Virgo, while the blue (metal-poor) GCs have a much more extended spatial distribution with significant populations still present beyond 83' (∼215 kpc) along the major axes of both M49 and M87. A comparison of our GC maps to the diffuse light in the outermost regions of M49 and M87 show remarkable agreement in the shape, ellipticity, and boxiness of both luminous systems. We also find evidence for spatial enhancements of GCs surrounding M87 that may be indicative of recent interactions or an ongoing merger history. We compare the GC map to that of the locations of Virgo galaxies and the X-ray intracluster gas, and find generally good agreement between these various baryonic structures. We calculate the Virgo cluster contains a total population of N {sub GC} = 67, 300 ± 14, 400, of which 35% are located in M87 and M49 alone. For the first time, we compute a cluster-wide specific frequency S {sub N,} {sub CL} = 2.8 ± 0.7, after correcting for Virgo's diffuse light. We also find a GC-to-baryonic mass fraction ε {sub b} = 5.7 ± 1.1 × 10{sup –4} and a GC-to-total cluster mass formation efficiency ε {sub t} = 2.9 ± 0.5 × 10{sup –5

  15. THE NEXT GENERATION VIRGO CLUSTER SURVEY (NGVS). I. INTRODUCTION TO THE SURVEY

    International Nuclear Information System (INIS)

    Ferrarese, Laura; Côté, Patrick; Gwyn, S. D. J.; MacArthur, Lauren A.; McConnachie, Alan W.; Blakeslee, John P.; Cuillandre, Jean-Charles; Peng, Eric W.; Duc, Pierre-Alain; Boselli, A.; Mei, Simona; Erben, Thomas; Durrell, Patrick R.; Christopher Mihos, J.; Jordán, Andrés; Puzia, Thomas H.; Lançon, Ariane; Emsellem, Eric; Balogh, Michael L.; Van Waerbeke, Ludovic

    2012-01-01

    The Next Generation Virgo Cluster Survey (NGVS) is a program that uses the 1 deg 2 MegaCam instrument on the Canada-France-Hawaii Telescope to carry out a comprehensive optical imaging survey of the Virgo cluster, from its core to its virial radius—covering a total area of 104 deg 2 —in the u*griz bandpasses. Thanks to a dedicated data acquisition strategy and processing pipeline, the NGVS reaches a point-source depth of g ≈ 25.9 mag (10σ) and a surface brightness limit of μ g ∼ 29 mag arcsec –2 (2σ above the mean sky level), thus superseding all previous optical studies of this benchmark galaxy cluster. In this paper, we give an overview of the technical aspects of the survey, such as areal coverage, field placement, choice of filters, limiting magnitudes, observing strategies, data processing and calibration pipelines, survey timeline, and data products. We also describe the primary scientific topics of the NGVS, which include: the galaxy luminosity and mass functions; the color-magnitude relation; galaxy scaling relations; compact stellar systems; galactic nuclei; the extragalactic distance scale; the large-scale environment of the cluster and its relationship to the Local Supercluster; diffuse light and the intracluster medium; galaxy interactions and evolutionary processes; and extragalactic star clusters. In addition, we describe a number of ancillary programs dealing with 'foreground' and 'background' science topics, including the study of high-inclination trans-Neptunian objects; the structure of the Galactic halo in the direction of the Virgo Overdensity and Sagittarius Stream; the measurement of cosmic shear, galaxy-galaxy, and cluster lensing; and the identification of distant galaxy clusters, and strong-lensing events.

  16. Factor IX assay

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003679.htm Factor IX assay To use the sharing features on ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  17. MEASURING THE ULTIMATE HALO MASS OF GALAXY CLUSTERS: REDSHIFTS AND MASS PROFILES FROM THE HECTOSPEC CLUSTER SURVEY (HeCS)

    International Nuclear Information System (INIS)

    Rines, Kenneth; Geller, Margaret J.; Kurtz, Michael J.; Diaferio, Antonaldo

    2013-01-01

    The infall regions of galaxy clusters represent the largest gravitationally bound structures in a ΛCDM universe. Measuring cluster mass profiles into the infall regions provides an estimate of the ultimate mass of these halos. We use the caustic technique to measure cluster mass profiles from galaxy redshifts obtained with the Hectospec Cluster Survey (HeCS), an extensive spectroscopic survey of galaxy clusters with MMT/Hectospec. We survey 58 clusters selected by X-ray flux at 0.1 200 , a new observational cosmological test in essential agreement with simulations. Summed profiles binned in M 200 and in L X demonstrate that the predicted Navarro-Frenk-White form of the density profile is a remarkably good representation of the data in agreement with weak lensing results extending to large radius. The concentration of these summed profiles is also consistent with theoretical predictions.

  18. The swift UVOT stars survey. I. Methods and test clusters

    Energy Technology Data Exchange (ETDEWEB)

    Siegel, Michael H.; Porterfield, Blair L.; Linevsky, Jacquelyn S.; Bond, Howard E.; Hoversten, Erik A.; Berrier, Joshua L.; Gronwall, Caryl A. [Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Holland, Stephen T. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Breeveld, Alice A. [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom); Brown, Peter J., E-mail: siegel@astro.psu.edu, E-mail: blp14@psu.edu, E-mail: heb11@psu.edu, E-mail: caryl@astro.psu.edu, E-mail: sholland@stsci.edu, E-mail: aab@mssl.ucl.ac.uk, E-mail: grbpeter@yahoo.com [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A. and M. University, Department of Physics and Astronomy, 4242 TAMU, College Station, TX 77843 (United States)

    2014-12-01

    We describe the motivations and background of a large survey of nearby stellar populations using the Ultraviolet Optical Telescope (UVOT) on board the Swift Gamma-Ray Burst Mission. UVOT, with its wide field, near-UV sensitivity, and 2.″3 spatial resolution, is uniquely suited to studying nearby stellar populations and providing insight into the near-UV properties of hot stars and the contribution of those stars to the integrated light of more distant stellar populations. We review the state of UV stellar photometry, outline the survey, and address problems specific to wide- and crowded-field UVOT photometry. We present color–magnitude diagrams of the nearby open clusters M67, NGC 188, and NGC 2539, and the globular cluster M79. We demonstrate that UVOT can easily discern the young- and intermediate-age main sequences, blue stragglers, and hot white dwarfs, producing results consistent with previous studies. We also find that it characterizes the blue horizontal branch of M79 and easily identifies a known post-asymptotic giant branch star.

  19. The swift UVOT stars survey. I. Methods and test clusters

    International Nuclear Information System (INIS)

    Siegel, Michael H.; Porterfield, Blair L.; Linevsky, Jacquelyn S.; Bond, Howard E.; Hoversten, Erik A.; Berrier, Joshua L.; Gronwall, Caryl A.; Holland, Stephen T.; Breeveld, Alice A.; Brown, Peter J.

    2014-01-01

    We describe the motivations and background of a large survey of nearby stellar populations using the Ultraviolet Optical Telescope (UVOT) on board the Swift Gamma-Ray Burst Mission. UVOT, with its wide field, near-UV sensitivity, and 2.″3 spatial resolution, is uniquely suited to studying nearby stellar populations and providing insight into the near-UV properties of hot stars and the contribution of those stars to the integrated light of more distant stellar populations. We review the state of UV stellar photometry, outline the survey, and address problems specific to wide- and crowded-field UVOT photometry. We present color–magnitude diagrams of the nearby open clusters M67, NGC 188, and NGC 2539, and the globular cluster M79. We demonstrate that UVOT can easily discern the young- and intermediate-age main sequences, blue stragglers, and hot white dwarfs, producing results consistent with previous studies. We also find that it characterizes the blue horizontal branch of M79 and easily identifies a known post-asymptotic giant branch star.

  20. A faint galaxy redshift survey behind massive clusters

    Energy Technology Data Exchange (ETDEWEB)

    Frye, Brenda Louise [Univ. of California, Berkeley, CA (United States)

    1999-05-01

    This thesis is concerned with the gravitational lensing effect by massive galaxy clusters. We have explored a new technique for measuring galaxy masses and for detecting high-z galaxies by their optical colors. A redshift survey has been obtained at the Keck for a magnitude limited sample of objects (I<23) behind three clusters, A1689, A2390, and A2218 within a radius of 0.5M pc. For each cluster we see both a clear trend of increasing flux and redshift towards the center. This behavior is the result of image magnifications, such that at fixed redshift one sees further down the luminosity function. The gradient of this magnification is, unlike measurements of image distortion, sensitive to the mass profile, and found to depart strongly from a pure isothermal halo. We have found that V RI color selection can be used effectively as a discriminant for finding high-z galaxies behind clusters and present five 4.1 < z < 5.1 spectra which are of very high quality due to their high mean magnification of ~20, showing strong, visibly-saturated interstellar metal lines in some cases. We have also investigated the radio ring lens PKS 1830-211, locating the source and multiple images and detected molecular absorption at mm wavelengths. Broad molecular absorption of width 1/40kms is found toward the southwest component only, where surprisingly it does not reach the base of the continuum, which implies incomplete coverage of the SW component by molecular gas, despite the small projected size of the source, less than 1/8h pc at the absorption redshift.

  1. The IMACS Cluster Building Survey. I. Description of the Survey and Analysis Methods

    Science.gov (United States)

    Oemler Jr., Augustus; Dressler, Alan; Gladders, Michael G.; Rigby, Jane R.; Bai, Lei; Kelson, Daniel; Villanueva, Edward; Fritz, Jacopo; Rieke, George; Poggianti, Bianca M.; hide

    2013-01-01

    The IMACS Cluster Building Survey uses the wide field spectroscopic capabilities of the IMACS spectrograph on the 6.5 m Baade Telescope to survey the large-scale environment surrounding rich intermediate-redshift clusters of galaxies. The goal is to understand the processes which may be transforming star-forming field galaxies into quiescent cluster members as groups and individual galaxies fall into the cluster from the surrounding supercluster. This first paper describes the survey: the data taking and reduction methods. We provide new calibrations of star formation rates (SFRs) derived from optical and infrared spectroscopy and photometry. We demonstrate that there is a tight relation between the observed SFR per unit B luminosity, and the ratio of the extinctions of the stellar continuum and the optical emission lines.With this, we can obtain accurate extinction-corrected colors of galaxies. Using these colors as well as other spectral measures, we determine new criteria for the existence of ongoing and recent starbursts in galaxies.

  2. THE IMACS CLUSTER BUILDING SURVEY. I. DESCRIPTION OF THE SURVEY AND ANALYSIS METHODS

    Energy Technology Data Exchange (ETDEWEB)

    Oemler, Augustus Jr.; Dressler, Alan; Kelson, Daniel; Villanueva, Edward [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101-1292 (United States); Gladders, Michael G. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Rigby, Jane R. [Observational Cosmology Lab, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Bai Lei [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Fritz, Jacopo [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Rieke, George [Steward Observatory, University of Arizona, Tucson, AZ 8572 (United States); Poggianti, Bianca M.; Vulcani, Benedetta, E-mail: oemler@obs.carnegiescience.edu [INAF-Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy)

    2013-06-10

    The IMACS Cluster Building Survey uses the wide field spectroscopic capabilities of the IMACS spectrograph on the 6.5 m Baade Telescope to survey the large-scale environment surrounding rich intermediate-redshift clusters of galaxies. The goal is to understand the processes which may be transforming star-forming field galaxies into quiescent cluster members as groups and individual galaxies fall into the cluster from the surrounding supercluster. This first paper describes the survey: the data taking and reduction methods. We provide new calibrations of star formation rates (SFRs) derived from optical and infrared spectroscopy and photometry. We demonstrate that there is a tight relation between the observed SFR per unit B luminosity, and the ratio of the extinctions of the stellar continuum and the optical emission lines. With this, we can obtain accurate extinction-corrected colors of galaxies. Using these colors as well as other spectral measures, we determine new criteria for the existence of ongoing and recent starbursts in galaxies.

  3. Factor IX gene haplotypes in Amerindians.

    Science.gov (United States)

    Franco, R F; Araújo, A G; Zago, M A; Guerreiro, J F; Figueiredo, M S

    1997-02-01

    We have determined the haplotypes of the factor IX gene for 95 Indians from 5 Brazilian Amazon tribes: Wayampí, Wayana-Apalaí, Kayapó, Arára, and Yanomámi. Eight polymorphisms linked to the factor IX gene were investigated: MseI (at 5', nt -698), BamHI (at 5', nt -561), DdeI (intron 1), BamHI (intron 2), XmnI (intron 3), TaqI (intron 4), MspI (intron 4), and HhaI (at 3', approximately 8 kb). The results of the haplotype distribution and the allele frequencies for each of the factor IX gene polymorphisms in Amerindians were similar to the results reported for Asian populations but differed from results for other ethnic groups. Only five haplotypes were identified within the entire Amerindian study population, and the haplotype distribution was significantly different among the five tribes, with one (Arára) to four (Wayampí) haplotypes being found per tribe. These findings indicate a significant heterogeneity among the Indian tribes and contrast with the homogeneous distribution of the beta-globin gene cluster haplotypes but agree with our recent findings on the distribution of alpha-globin gene cluster haplotypes and the allele frequencies for six VNTRs in the same Amerindian tribes. Our data represent the first study of factor IX-associated polymorphisms in Amerindian populations and emphasizes the applicability of these genetic markers for population and human evolution studies.

  4. Massive open star clusters using the VVV survey. II. Discovery of six clusters with Wolf-Rayet stars

    Science.gov (United States)

    Chené, A.-N.; Borissova, J.; Bonatto, C.; Majaess, D. J.; Baume, G.; Clarke, J. R. A.; Kurtev, R.; Schnurr, O.; Bouret, J.-C.; Catelan, M.; Emerson, J. P.; Feinstein, C.; Geisler, D.; de Grijs, R.; Hervé, A.; Ivanov, V. D.; Kumar, M. S. N.; Lucas, P.; Mahy, L.; Martins, F.; Mauro, F.; Minniti, D.; Moni Bidin, C.

    2013-01-01

    Context. The ESO Public Survey "VISTA Variables in the Vía Láctea" (VVV) provides deep multi-epoch infrared observations for an unprecedented 562 sq. degrees of the Galactic bulge, and adjacent regions of the disk. Nearly 150 new open clusters and cluster candidates have been discovered in this survey. Aims: This is the second in a series of papers about young, massive open clusters observed using the VVV survey. We present the first study of six recently discovered clusters. These clusters contain at least one newly discovered Wolf-Rayet (WR) star. Methods: Following the methodology presented in the first paper of the series, wide-field, deep JHKs VVV observations, combined with new infrared spectroscopy, are employed to constrain fundamental parameters for a subset of clusters. Results: We find that the six studied stellar groups are real young (2-7 Myr) and massive (between 0.8 and 2.2 × 103 M⊙) clusters. They are highly obscured (AV ~ 5-24 mag) and compact (1-2 pc). In addition to WR stars, two of the six clusters also contain at least one red supergiant star, and one of these two clusters also contains a blue supergiant. We claim the discovery of 8 new WR stars, and 3 stars showing WR-like emission lines which could be classified WR or OIf. Preliminary analysis provides initial masses of ~30-50 M⊙ for the WR stars. Finally, we discuss the spiral structure of the Galaxy using the six new clusters as tracers, together with the previously studied VVV clusters. Based on observations with ISAAC, VLT, ESO (programme 087.D-0341A), New Technology Telescope at ESO's La Silla Observatory (programme 087.D-0490A) and with the Clay telescope at the Las Campanas Observatory (programme CN2011A-086). Also based on data from the VVV survey (programme 172.B-2002).

  5. THE HST/ACS COMA CLUSTER SURVEY. IV. INTERGALACTIC GLOBULAR CLUSTERS AND THE MASSIVE GLOBULAR CLUSTER SYSTEM AT THE CORE OF THE COMA GALAXY CLUSTER

    International Nuclear Information System (INIS)

    Peng, Eric W.; Ferguson, Henry C.; Goudfrooij, Paul; Hammer, Derek; Lucey, John R.; Marzke, Ronald O.; Puzia, Thomas H.; Carter, David; Balcells, Marc; Bridges, Terry; Chiboucas, Kristin; Del Burgo, Carlos; Graham, Alister W.; Guzman, Rafael; Hudson, Michael J.; Matkovic, Ana

    2011-01-01

    Intracluster stellar populations are a natural result of tidal interactions in galaxy clusters. Measuring these populations is difficult, but important for understanding the assembly of the most massive galaxies. The Coma cluster of galaxies is one of the nearest truly massive galaxy clusters and is host to a correspondingly large system of globular clusters (GCs). We use imaging from the HST/ACS Coma Cluster Survey to present the first definitive detection of a large population of intracluster GCs (IGCs) that fills the Coma cluster core and is not associated with individual galaxies. The GC surface density profile around the central massive elliptical galaxy, NGC 4874, is dominated at large radii by a population of IGCs that extend to the limit of our data (R +4000 -5000 (systematic) IGCs out to this radius, and that they make up ∼70% of the central GC system, making this the largest GC system in the nearby universe. Even including the GC systems of other cluster galaxies, the IGCs still make up ∼30%-45% of the GCs in the cluster core. Observational limits from previous studies of the intracluster light (ICL) suggest that the IGC population has a high specific frequency. If the IGC population has a specific frequency similar to high-S N dwarf galaxies, then the ICL has a mean surface brightness of μ V ∼ 27 mag arcsec -2 and a total stellar mass of roughly 10 12 M sun within the cluster core. The ICL makes up approximately half of the stellar luminosity and one-third of the stellar mass of the central (NGC 4874+ICL) system. The color distribution of the IGC population is bimodal, with blue, metal-poor GCs outnumbering red, metal-rich GCs by a ratio of 4:1. The inner GCs associated with NGC 4874 also have a bimodal distribution in color, but with a redder metal-poor population. The fraction of red IGCs (20%), and the red color of those GCs, implies that IGCs can originate from the halos of relatively massive, L* galaxies, and not solely from the disruption of

  6. Clustering of galaxies around AGNs in the HSC Wide survey

    Science.gov (United States)

    Shirasaki, Yuji; Akiyama, Masayuki; Nagao, Tohru; Toba, Yoshiki; He, Wanqiu; Ohishi, Masatoshi; Mizumoto, Yoshihiko; Miyazaki, Satoshi; Nishizawa, Atsushi J.; Usuda, Tomonori

    2018-01-01

    We have measured the clustering of galaxies around active galactic nuclei (AGNs) for which single-epoch virial masses of the super-massive black hole (SMBH) are available to investigate the relation between the large-scale environment of AGNs and the evolution of SMBHs. The AGN samples used in this work were derived from the Sloan Digital Sky Survey (SDSS) observations and the galaxy samples were from the 240 deg2 S15b data of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). The investigated redshift range is 0.6-3.0, and the masses of the SMBHs lie in the range 107.5-1010 M⊙. The absolute magnitude of the galaxy samples reaches to Mλ310 ˜ -18 at rest-frame wavelength 310 nm for the low-redshift end of the samples. More than 70% of the galaxies in the analysis are blue. We found a significant dependence of the cross-correlation length on redshift, which primarily reflects the brightness-dependence of the galaxy clustering. At the lowest redshifts the cross-correlation length increases from 7 h-1 Mpc around Mλ310 = -19 mag to >10 h-1 Mpc beyond Mλ310 = -20 mag. No significant dependence of the cross-correlation length on BH mass was found for whole galaxy samples dominated by blue galaxies, while there was an indication of BH mass dependence in the cross-correlation with red galaxies. These results provides a picture of the environment of AGNs studied in this paper being enriched with blue star-forming galaxies, and a fraction of the galaxies are evolving into red galaxies along with the evolution of SMBHs in that system.

  7. IS THE TWO MICRON ALL SKY SURVEY CLUSTERING DIPOLE CONVERGENT?

    International Nuclear Information System (INIS)

    Bilicki, Maciej; Chodorowski, Michal; Jarrett, Thomas; Mamon, Gary A.

    2011-01-01

    There is a long-standing controversy about the convergence of the dipole moment of the galaxy angular distribution (the so-called clustering dipole). Is the dipole convergent at all, and if so, what is the scale of the convergence? We study the growth of the clustering dipole of galaxies as a function of the limiting flux of the sample from the Two Micron All Sky Survey (2MASS). Contrary to some earlier claims, we find that the dipole does not converge before the completeness limit of the 2MASS Extended Source Catalog, i.e., up to 13.5 mag in the near-infrared K s band (equivalent to an effective distance of 300 Mpc h -1 ). We compare the observed growth of the dipole with the theoretically expected, conditional one (i.e., given the velocity of the Local Group relative to the cosmic microwave background), for the ΛCDM power spectrum and cosmological parameters constrained by the Wilkinson Microwave Anisotropy Probe. The observed growth turns out to be within 1σ confidence level of its theoretical counterpart once the proper observational window of the 2MASS flux-limited catalog is included. For a contrast, if the adopted window is a top hat, then the predicted dipole grows significantly faster and converges (within the errors) to its final value for a distance of about 300 Mpc h -1 . By comparing the observational windows, we show that for a given flux limit and a corresponding distance limit, the 2MASS flux-weighted window passes less large-scale signal than the top-hat one. We conclude that the growth of the 2MASS dipole for effective distances greater than 200 Mpc h -1 is only apparent. On the other hand, for a distance of 80 Mpc h -1 (mean depth of the 2MASS Redshift Survey) and the ΛCDM power spectrum, the true dipole is expected to reach only ∼80% of its final value. Eventually, since for the window function of 2MASS the predicted growth is consistent with the observed one, we can compare the two to evaluate β ≡ Ω m 0.55 /b. The result is β = 0.38

  8. Young star clusters in nearby molecular clouds

    Science.gov (United States)

    Getman, K. V.; Kuhn, M. A.; Feigelson, E. D.; Broos, P. S.; Bate, M. R.; Garmire, G. P.

    2018-06-01

    The SFiNCs (Star Formation in Nearby Clouds) project is an X-ray/infrared study of the young stellar populations in 22 star-forming regions with distances ≲ 1 kpc designed to extend our earlier MYStIX (Massive Young Star-Forming Complex Study in Infrared and X-ray) survey of more distant clusters. Our central goal is to give empirical constraints on cluster formation mechanisms. Using parametric mixture models applied homogeneously to the catalogue of SFiNCs young stars, we identify 52 SFiNCs clusters and 19 unclustered stellar structures. The procedure gives cluster properties including location, population, morphology, association with molecular clouds, absorption, age (AgeJX), and infrared spectral energy distribution (SED) slope. Absorption, SED slope, and AgeJX are age indicators. SFiNCs clusters are examined individually, and collectively with MYStIX clusters, to give the following results. (1) SFiNCs is dominated by smaller, younger, and more heavily obscured clusters than MYStIX. (2) SFiNCs cloud-associated clusters have the high ellipticities aligned with their host molecular filaments indicating morphology inherited from their parental clouds. (3) The effect of cluster expansion is evident from the radius-age, radius-absorption, and radius-SED correlations. Core radii increase dramatically from ˜0.08 to ˜0.9 pc over the age range 1-3.5 Myr. Inferred gas removal time-scales are longer than 1 Myr. (4) Rich, spatially distributed stellar populations are present in SFiNCs clouds representing early generations of star formation. An appendix compares the performance of the mixture models and non-parametric minimum spanning tree to identify clusters. This work is a foundation for future SFiNCs/MYStIX studies including disc longevity, age gradients, and dynamical modelling.

  9. VizieR Online Data Catalog: HST/ACS Coma Cluster Survey. VI. (den Brok+, 2011)

    Science.gov (United States)

    den Brok, M.; Peletier, R. F.; Valentijn, E. A.; Balcells, M.; Carter, D.; Erwin, P.; Ferguson, H. C.; Goudfrooij, P.; Graham, A. W.; Hammer, D.; Lucey, J. R.; Trentham, N.; Guzman, R.; Hoyos, C.; Verdoes Kleijn, G.; Jogee, S.; Karick, A. M.; Marinova, I.; Mouhcine, M.; Weinzirl, T.

    2018-01-01

    We have used the data from the HST/ACS Coma Cluster Survey, a deep two-passband imaging survey of the Coma cluster. A full description of the observations and data reduction can be found in Paper I (Carter et al., 2008ApJS..176..424C). We have derived colour gradients for a sample of confirmed or very likely Coma cluster members. (2 data files).

  10. PHAT STELLAR CLUSTER SURVEY. I. YEAR 1 CATALOG AND INTEGRATED PHOTOMETRY

    International Nuclear Information System (INIS)

    Johnson, L. Clifton; Dalcanton, Julianne J.; Fouesneau, Morgan; Hodge, Paul W.; Weisz, Daniel R.; Williams, Benjamin F.; Beerman, Lori C.; Seth, Anil C.; Caldwell, Nelson; Gouliermis, Dimitrios A.; Larsen, Søren S.; Olsen, Knut A. G.; San Roman, Izaskun; Sarajedini, Ata; Bianchi, Luciana; Dolphin, Andrew E.; Girardi, Léo; Guhathakurta, Puragra; Kalirai, Jason; Lang, Dustin

    2012-01-01

    The Panchromatic Hubble Andromeda Treasury (PHAT) survey is an ongoing Hubble Space Telescope (HST) multi-cycle program to obtain high spatial resolution imaging of one-third of the M31 disk at ultraviolet through near-infrared wavelengths. In this paper, we present the first installment of the PHAT stellar cluster catalog. When completed, the PHAT cluster catalog will be among the largest and most comprehensive surveys of resolved star clusters in any galaxy. The exquisite spatial resolution achieved with HST has allowed us to identify hundreds of new clusters that were previously inaccessible with existing ground-based surveys. We identify 601 clusters in the Year 1 sample, representing more than a factor of four increase over previous catalogs within the current survey area (390 arcmin 2 ). This work presents results derived from the first ∼25% of the survey data; we estimate that the final sample will include ∼2500 clusters. For the Year 1 objects, we present a catalog with positions, radii, and six-band integrated photometry. Along with a general characterization of the cluster luminosities and colors, we discuss the cluster luminosity function, the cluster size distributions, and highlight a number of individually interesting clusters found in the Year 1 search.

  11. PHAT STELLAR CLUSTER SURVEY. I. YEAR 1 CATALOG AND INTEGRATED PHOTOMETRY

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L. Clifton; Dalcanton, Julianne J.; Fouesneau, Morgan; Hodge, Paul W.; Weisz, Daniel R.; Williams, Benjamin F.; Beerman, Lori C. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Seth, Anil C. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Caldwell, Nelson [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Gouliermis, Dimitrios A. [Institut fuer Theoretische Astrophysik, Zentrum fuer Astronomie der Universitaet Heidelberg, Albert-Ueberle-Strasse 2, D-69120 Heidelberg (Germany); Larsen, Soren S. [Department of Astrophysics, IMAPP, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Olsen, Knut A. G. [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); San Roman, Izaskun; Sarajedini, Ata [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611-2055 (United States); Bianchi, Luciana [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Girardi, Leo [Osservatorio Astronomico di Padova-INAF, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Guhathakurta, Puragra [Department of Astronomy and Astrophysics, University of California Observatories/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Kalirai, Jason [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Lang, Dustin, E-mail: lcjohnso@astro.washington.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); and others

    2012-06-20

    The Panchromatic Hubble Andromeda Treasury (PHAT) survey is an ongoing Hubble Space Telescope (HST) multi-cycle program to obtain high spatial resolution imaging of one-third of the M31 disk at ultraviolet through near-infrared wavelengths. In this paper, we present the first installment of the PHAT stellar cluster catalog. When completed, the PHAT cluster catalog will be among the largest and most comprehensive surveys of resolved star clusters in any galaxy. The exquisite spatial resolution achieved with HST has allowed us to identify hundreds of new clusters that were previously inaccessible with existing ground-based surveys. We identify 601 clusters in the Year 1 sample, representing more than a factor of four increase over previous catalogs within the current survey area (390 arcmin{sup 2}). This work presents results derived from the first {approx}25% of the survey data; we estimate that the final sample will include {approx}2500 clusters. For the Year 1 objects, we present a catalog with positions, radii, and six-band integrated photometry. Along with a general characterization of the cluster luminosities and colors, we discuss the cluster luminosity function, the cluster size distributions, and highlight a number of individually interesting clusters found in the Year 1 search.

  12. The CfA-Rosat Survey of Distant Clusters of Galaxies

    Science.gov (United States)

    McNamara, Brian

    1998-01-01

    We (Vikhlinin, McNamara, Forman, Jones, Hornstrup, Quintana) have completed a new survey of distant clusters of galaxies, which we use to to study cluster evolution over cosmological timescales. The clusters were identified as extended X-ray sources in 650 ROSAT PSPC images of high Galactic latitude fields. Our catalog of approximately 230 extended X-ray sources covers 160 square degrees on the sky. Ours is the largest of the several ROSAT serendipitous cluster surveys in progress (e.g. SHARC, Rosati, WARPS etc.). Using V,R,I imagery obtained at several observatories, we find that greater than 90% of the X-ray sources are associated with distant clusters of galaxies. We have obtained spectroscopic redshifts for nearly 80 clusters in our catalog, and we have measured photometric redshifts for the remaining clusters. Our sample contains more than 20 clusters at z > 0.5. I will discuss the logN-logS relationship for our clusters. Because our large survey area, we are able to confirm the evolution of the most luminous distant clusters first seen in the Einstein Extended Medium Sensitivity Survey. In addition, I will discuss the relationships between optical richness, core radius, and X-ray luminosity for distant, X-ray-selected clusters.

  13. Choosing a Cluster Sampling Design for Lot Quality Assurance Sampling Surveys.

    Directory of Open Access Journals (Sweden)

    Lauren Hund

    Full Text Available Lot quality assurance sampling (LQAS surveys are commonly used for monitoring and evaluation in resource-limited settings. Recently several methods have been proposed to combine LQAS with cluster sampling for more timely and cost-effective data collection. For some of these methods, the standard binomial model can be used for constructing decision rules as the clustering can be ignored. For other designs, considered here, clustering is accommodated in the design phase. In this paper, we compare these latter cluster LQAS methodologies and provide recommendations for choosing a cluster LQAS design. We compare technical differences in the three methods and determine situations in which the choice of method results in a substantively different design. We consider two different aspects of the methods: the distributional assumptions and the clustering parameterization. Further, we provide software tools for implementing each method and clarify misconceptions about these designs in the literature. We illustrate the differences in these methods using vaccination and nutrition cluster LQAS surveys as example designs. The cluster methods are not sensitive to the distributional assumptions but can result in substantially different designs (sample sizes depending on the clustering parameterization. However, none of the clustering parameterizations used in the existing methods appears to be consistent with the observed data, and, consequently, choice between the cluster LQAS methods is not straightforward. Further research should attempt to characterize clustering patterns in specific applications and provide suggestions for best-practice cluster LQAS designs on a setting-specific basis.

  14. Choosing a Cluster Sampling Design for Lot Quality Assurance Sampling Surveys.

    Science.gov (United States)

    Hund, Lauren; Bedrick, Edward J; Pagano, Marcello

    2015-01-01

    Lot quality assurance sampling (LQAS) surveys are commonly used for monitoring and evaluation in resource-limited settings. Recently several methods have been proposed to combine LQAS with cluster sampling for more timely and cost-effective data collection. For some of these methods, the standard binomial model can be used for constructing decision rules as the clustering can be ignored. For other designs, considered here, clustering is accommodated in the design phase. In this paper, we compare these latter cluster LQAS methodologies and provide recommendations for choosing a cluster LQAS design. We compare technical differences in the three methods and determine situations in which the choice of method results in a substantively different design. We consider two different aspects of the methods: the distributional assumptions and the clustering parameterization. Further, we provide software tools for implementing each method and clarify misconceptions about these designs in the literature. We illustrate the differences in these methods using vaccination and nutrition cluster LQAS surveys as example designs. The cluster methods are not sensitive to the distributional assumptions but can result in substantially different designs (sample sizes) depending on the clustering parameterization. However, none of the clustering parameterizations used in the existing methods appears to be consistent with the observed data, and, consequently, choice between the cluster LQAS methods is not straightforward. Further research should attempt to characterize clustering patterns in specific applications and provide suggestions for best-practice cluster LQAS designs on a setting-specific basis.

  15. A DEEP, WIDE-FIELD Hα SURVEY OF NEARBY CLUSTERS OF GALAXIES: DATA

    International Nuclear Information System (INIS)

    Sakai, Shoko; Kennicutt, Robert C. Jr.; Moss, Chris

    2012-01-01

    We present the results of a wide-field Hα imaging survey of eight nearby (z = 0.02-0.03) Abell clusters. We have measured Hα fluxes and equivalent widths for 465 galaxies, of which 360 are new detections. The survey was designed to obtain complete emission-line-selected inventories of star-forming galaxies in the inner regions of these clusters, extending to star formation rates below 0.1 M ☉ yr –1 . This paper describes the observations, data processing, and source identification procedures, and presents an Hα and R-band catalog of detected cluster members and other candidates. Future papers in the series will use these data to study the completeness of spectroscopically based star formation surveys, and to quantify the effects of cluster environment on the present-day populations of star-forming galaxies. The data will also provide a valuable foundation for imaging surveys of redshifted Hα emission in more distant clusters.

  16. Performance of small cluster surveys and the clustered LQAS design to estimate local-level vaccination coverage in Mali.

    Science.gov (United States)

    Minetti, Andrea; Riera-Montes, Margarita; Nackers, Fabienne; Roederer, Thomas; Koudika, Marie Hortense; Sekkenes, Johanne; Taconet, Aurore; Fermon, Florence; Touré, Albouhary; Grais, Rebecca F; Checchi, Francesco

    2012-10-12

    Estimation of vaccination coverage at the local level is essential to identify communities that may require additional support. Cluster surveys can be used in resource-poor settings, when population figures are inaccurate. To be feasible, cluster samples need to be small, without losing robustness of results. The clustered LQAS (CLQAS) approach has been proposed as an alternative, as smaller sample sizes are required. We explored (i) the efficiency of cluster surveys of decreasing sample size through bootstrapping analysis and (ii) the performance of CLQAS under three alternative sampling plans to classify local VC, using data from a survey carried out in Mali after mass vaccination against meningococcal meningitis group A. VC estimates provided by a 10 × 15 cluster survey design were reasonably robust. We used them to classify health areas in three categories and guide mop-up activities: i) health areas not requiring supplemental activities; ii) health areas requiring additional vaccination; iii) health areas requiring further evaluation. As sample size decreased (from 10 × 15 to 10 × 3), standard error of VC and ICC estimates were increasingly unstable. Results of CLQAS simulations were not accurate for most health areas, with an overall risk of misclassification greater than 0.25 in one health area out of three. It was greater than 0.50 in one health area out of two under two of the three sampling plans. Small sample cluster surveys (10 × 15) are acceptably robust for classification of VC at local level. We do not recommend the CLQAS method as currently formulated for evaluating vaccination programmes.

  17. Performance of small cluster surveys and the clustered LQAS design to estimate local-level vaccination coverage in Mali

    Directory of Open Access Journals (Sweden)

    Minetti Andrea

    2012-10-01

    Full Text Available Abstract Background Estimation of vaccination coverage at the local level is essential to identify communities that may require additional support. Cluster surveys can be used in resource-poor settings, when population figures are inaccurate. To be feasible, cluster samples need to be small, without losing robustness of results. The clustered LQAS (CLQAS approach has been proposed as an alternative, as smaller sample sizes are required. Methods We explored (i the efficiency of cluster surveys of decreasing sample size through bootstrapping analysis and (ii the performance of CLQAS under three alternative sampling plans to classify local VC, using data from a survey carried out in Mali after mass vaccination against meningococcal meningitis group A. Results VC estimates provided by a 10 × 15 cluster survey design were reasonably robust. We used them to classify health areas in three categories and guide mop-up activities: i health areas not requiring supplemental activities; ii health areas requiring additional vaccination; iii health areas requiring further evaluation. As sample size decreased (from 10 × 15 to 10 × 3, standard error of VC and ICC estimates were increasingly unstable. Results of CLQAS simulations were not accurate for most health areas, with an overall risk of misclassification greater than 0.25 in one health area out of three. It was greater than 0.50 in one health area out of two under two of the three sampling plans. Conclusions Small sample cluster surveys (10 × 15 are acceptably robust for classification of VC at local level. We do not recommend the CLQAS method as currently formulated for evaluating vaccination programmes.

  18. Survey of the numerical characterisation of 2-D complex clusters

    NARCIS (Netherlands)

    Maggi, F.

    2003-01-01

    The study of cluster format ion is common in many fields of science and technology (aerosols, colloidal suspensions, hetero-disperse particulate systems in general, growth processes far from equilibrium, etc.). The term "cluster" is a general word indicating an object consisting of a set of

  19. A survey of text clustering techniques used for web mining

    Directory of Open Access Journals (Sweden)

    Dan MUNTEANU

    2005-12-01

    Full Text Available This paper contains an overview of basic formulations and approaches to clustering. Then it presents two important clustering paradigms: a bottom-up agglomerative technique, which collects similar documents into larger and larger groups, and a top-down partitioning technique, which divides a corpus into topic-oriented partitions.

  20. A Hubble Space Telescope Survey of the Disk Cluster Population of M31. II. Advanced Camera for Surveys Pointings

    Science.gov (United States)

    Krienke, O. K.; Hodge, P. W.

    2008-01-01

    This paper reports on a survey of star clusters in M31 based on archival images from the Hubble Space Telescope. Paper I reported results from images obtained with the Wide Field Planetary Camera 2 (WFPC2) and this paper reports results from the Advanced Camera for Surveys (ACS). The ACS survey has yielded a total of 339 star clusters, 52 of which—mostly globular clusters—were found to have been cataloged previously. As for the previous survey, the luminosity function of the clusters drops steeply for absolute magnitudes fainter than MV = -3 the implied cluster mass function has a turnover for masses less than a few hundred solar masses. The color-integrated magnitude diagram of clusters shows three significant features: (1) a group of very red, luminous objects: the globular clusters, (2) a wide range in color for the fainter clusters, representing a considerable range in age and reddening, and (3) a maximum density of clusters centered approximately at V = 21, B - V = 0.30, V - I = 0.50, where there are intermediate-age, intermediate-mass clusters with ages close to 500 million years and masses of about 2000 solar masses. We give a brief qualitative interpretation of the distribution of clusters in the CMDs in terms of their formation and destruction rates. Based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for research in astronomy, Inc., under NASA contract NAS 5-26555.

  1. The Effects of Halo Assembly Bias on Self-Calibration in Galaxy Cluster Surveys

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hao-Yi; Rozo, Eduardo; Wechsler, Risa H.

    2008-08-07

    Self-calibration techniques for analyzing galaxy cluster counts utilize the abundance and the clustering amplitude of dark matter halos. These properties simultaneously constrain cosmological parameters and the cluster observable-mass relation. It was recently discovered that the clustering amplitude of halos depends not only on the halo mass, but also on various secondary variables, such as the halo formation time and the concentration; these dependences are collectively termed 'assembly bias'. Applying modified Fisher matrix formalism, we explore whether these secondary variables have a significant impact on the study of dark energy properties using the self-calibration technique in current (SDSS) and the near future (DES, SPT, and LSST) cluster surveys. The impact of the secondary dependence is determined by (1) the scatter in the observable-mass relation and (2) the correlation between observable and secondary variables. We find that for optical surveys, the secondary dependence does not significantly influence an SDSS-like survey; however, it may affect a DES-like survey (given the high scatter currently expected from optical clusters) and an LSST-like survey (even for low scatter values and low correlations). For an SZ survey such as SPT, the impact of secondary dependence is insignificant if the scatter is 20% or lower but can be enhanced by the potential high scatter values introduced by a highly-correlated background. Accurate modeling of the assembly bias is necessary for cluster self-calibration in the era of precision cosmology.

  2. Confronting the sound speed of dark energy with future cluster surveys

    DEFF Research Database (Denmark)

    Basse, Tobias; Eggers Bjaelde, Ole; Hannestad, Steen

    2012-01-01

    Future cluster surveys will observe galaxy clusters numbering in the hundred thousands. We consider this work how these surveys can be used to constrain dark energy parameters: in particular, the equation of state parameter w and the non-adiabatic sound speed c_s^2. We demonstrate that, in combin......Future cluster surveys will observe galaxy clusters numbering in the hundred thousands. We consider this work how these surveys can be used to constrain dark energy parameters: in particular, the equation of state parameter w and the non-adiabatic sound speed c_s^2. We demonstrate that......, in combination with Cosmic Microwave Background (CMB) observations from Planck, cluster surveys such as that in the ESA Euclid project will be able to determine a time-independent w with subpercent precision. Likewise, if the dark energy sound horizon falls within the length scales probed by the cluster survey......, then c_s^2 can be pinned down to within an order of magnitude. In the course of this work, we also investigate the process of dark energy virialisation in the presence of an arbitrary sound speed. We find that dark energy clustering and virialisation can lead to dark energy contributing to the total...

  3. A SURVEY ON DOCUMENT CLUSTERING APPROACH FOR COMPUTER FORENSIC ANALYSIS

    OpenAIRE

    Monika Raghuvanshi*, Rahul Patel

    2016-01-01

    In a forensic analysis, large numbers of files are examined. Much of the information comprises of in unstructured format, so it’s quite difficult task for computer forensic to perform such analysis. That’s why to do the forensic analysis of document within a limited period of time require a special approach such as document clustering. This paper review different document clustering algorithms methodologies for example K-mean, K-medoid, single link, complete link, average link in accorandance...

  4. CLUSTER LENSING PROFILES DERIVED FROM A REDSHIFT ENHANCEMENT OF MAGNIFIED BOSS-SURVEY GALAXIES

    International Nuclear Information System (INIS)

    Coupon, Jean; Umetsu, Keiichi; Broadhurst, Tom

    2013-01-01

    We report the first detection of a redshift-depth enhancement of background galaxies magnified by foreground clusters. Using 300,000 BOSS survey galaxies with accurate spectroscopic redshifts, we measure their mean redshift depth behind four large samples of optically selected clusters from the Sloan Digital Sky Survey (SDSS) surveys, totaling 5000-15,000 clusters. A clear trend of increasing mean redshift toward the cluster centers is found, averaged over each of the four cluster samples. In addition, we find similar but noisier behavior for an independent X-ray sample of 158 clusters lying in the foreground of the current BOSS sky area. By adopting the mass-richness relationships appropriate for each survey, we compare our results with theoretical predictions for each of the four SDSS cluster catalogs. The radial form of this redshift enhancement is well fitted by a richness-to-mass weighted composite Navarro-Frenk-White profile with an effective mass ranging between M 200 ∼ 1.4-1.8 × 10 14 M ☉ for the optically detected cluster samples, and M 200 ∼ 5.0 × 10 14 M ☉ for the X-ray sample. This lensing detection helps to establish the credibility of these SDSS cluster surveys, and provides a normalization for their respective mass-richness relations. In the context of the upcoming bigBOSS, Subaru Prime Focus Spectrograph, and EUCLID-NISP spectroscopic surveys, this method represents an independent means of deriving the masses of cluster samples for examining the cosmological evolution, and provides a relatively clean consistency check of weak-lensing measurements, free from the systematic limitations of shear calibration

  5. Choosing a Cluster Sampling Design for Lot Quality Assurance Sampling Surveys

    OpenAIRE

    Hund, Lauren; Bedrick, Edward J.; Pagano, Marcello

    2015-01-01

    Lot quality assurance sampling (LQAS) surveys are commonly used for monitoring and evaluation in resource-limited settings. Recently several methods have been proposed to combine LQAS with cluster sampling for more timely and cost-effective data collection. For some of these methods, the standard binomial model can be used for constructing decision rules as the clustering can be ignored. For other designs, considered here, clustering is accommodated in the design phase. In this paper, we comp...

  6. SPT-GMOS: A GEMINI/GMOS-SOUTH SPECTROSCOPIC SURVEY OF GALAXY CLUSTERS IN THE SPT-SZ SURVEY

    International Nuclear Information System (INIS)

    Bayliss, M. B.; Ruel, J.; Stubbs, C. W.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Carlstrom, J. E.; Chang, C. L.; Crawford, T. M.; Bleem, L. E.; Bocquet, S.; Brodwin, M.; Capasso, R.; Chiu, I.; Cho, H-M.; Clocchiatti, A.; Crites, A. T.; Haan, T. de

    2016-01-01

    We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg 2 of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W , of [O ii] λλ 3727, 3729 and H- δ , and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m ⋆ ). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ∼20% of the full SPT-SZ sample.

  7. SPT-GMOS: A Gemini/GMOS-South Spectroscopic Survey of Galaxy Clusters in the SPT-SZ Survey

    Science.gov (United States)

    Bayliss, M. B.; Ruel, J.; Stubbs, C. W.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Bleem, L. E.; Bocquet, S.; Brodwin, M.; Capasso, R.; Carlstrom, J. E.; Chang, C. L.; Chiu, I.; Cho, H.-M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dietrich, J. P.; Dobbs, M. A.; Doucouliagos, A. N.; Foley, R. J.; Forman, W. R.; Garmire, G. P.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Gupta, N.; Halverson, N. W.; Hlavacek-Larrondo, J.; Hoekstra, H.; Holder, G. P.; Holzapfel, W. L.; Hou, Z.; Hrubes, J. D.; Huang, N.; Jones, C.; Keisler, R.; Knox, L.; Lee, A. T.; Leitch, E. M.; von der Linden, A.; Luong-Van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L. M.; Mohr, J. J.; Murray, S. S.; Padin, S.; Pryke, C.; Rapetti, D.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Schrabback, T.; Shirokoff, E.; Song, J.; Spieler, H. G.; Stalder, B.; Stanford, S. A.; Staniszewski, Z.; Stark, A. A.; Story, K. T.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zenteno, A.

    2016-11-01

    We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg2 of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [O II] λλ3727, 3729 and H-δ, and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m⋆). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ∼20% of the full SPT-SZ sample.

  8. MOCCA-SURVEY Database I: Is NGC 6535 a dark star cluster harbouring an IMBH?

    Science.gov (United States)

    Askar, Abbas; Bianchini, Paolo; de Vita, Ruggero; Giersz, Mirek; Hypki, Arkadiusz; Kamann, Sebastian

    2017-01-01

    We describe the dynamical evolution of a unique type of dark star cluster model in which the majority of the cluster mass at Hubble time is dominated by an intermediate-mass black hole (IMBH). We analysed results from about 2000 star cluster models (Survey Database I) simulated using the Monte Carlo code MOnte Carlo Cluster simulAtor and identified these dark star cluster models. Taking one of these models, we apply the method of simulating realistic `mock observations' by utilizing the Cluster simulatiOn Comparison with ObservAtions (COCOA) and Simulating Stellar Cluster Observation (SISCO) codes to obtain the photometric and kinematic observational properties of the dark star cluster model at 12 Gyr. We find that the perplexing Galactic globular cluster NGC 6535 closely matches the observational photometric and kinematic properties of the dark star cluster model presented in this paper. Based on our analysis and currently observed properties of NGC 6535, we suggest that this globular cluster could potentially harbour an IMBH. If it exists, the presence of this IMBH can be detected robustly with proposed kinematic observations of NGC 6535.

  9. The Open Cluster Chemical Abundances and Mapping (OCCAM) Survey: Optical Extension for Neutron Capture Elements

    Science.gov (United States)

    Melendez, Matthew; O'Connell, Julia; Frinchaboy, Peter M.; Donor, John; Cunha, Katia M. L.; Shetrone, Matthew D.; Majewski, Steven R.; Zasowski, Gail; Pinsonneault, Marc H.; Roman-Lopes, Alexandre; Stassun, Keivan G.; APOGEE Team

    2017-01-01

    The Open Cluster Chemical Abundance & Mapping (OCCAM) survey is a systematic survey of Galactic open clusters using data primarily from the SDSS-III/APOGEE-1 survey. However, neutron capture elements are very limited in the IR region covered by APOGEE. In an effort to fully study detailed Galactic chemical evolution, we are conducting a high resolution (R~60,000) spectroscopic abundance analysis of neutron capture elements for OCCAM clusters in the optical regime to complement the APOGEE results. As part of this effort, we present Ba II, La II, Ce II and Eu II results for a few open clusters without previous abundance measurements using data obtained at McDonald Observatory with the 2.1m Otto Struve telescope and Sandiford Echelle Spectrograph.This work is supported by an NSF AAG grant AST-1311835.

  10. The HST/ACS Coma Cluster Survey : II. Data Description and Source Catalogs

    NARCIS (Netherlands)

    Hammer, Derek; Kleijn, Gijs Verdoes; Hoyos, Carlos; den Brok, Mark; Balcells, Marc; Ferguson, Henry C.; Goudfrooij, Paul; Carter, David; Guzman, Rafael; Peletier, Reynier F.; Smith, Russell J.; Graham, Alister W.; Trentham, Neil; Peng, Eric; Puzia, Thomas H.; Lucey, John R.; Jogee, Shardha; Aguerri, Alfonso L.; Batcheldor, Dan; Bridges, Terry J.; Chiboucas, Kristin; Davies, Jonathan I.; del Burgo, Carlos; Erwin, Peter; Hornschemeier, Ann; Hudson, Michael J.; Huxor, Avon; Jenkins, Leigh; Karick, Arna; Khosroshahi, Habib; Kourkchi, Ehsan; Komiyama, Yutaka; Lotz, Jennifer; Marzke, Ronald O.; Marinova, Irina; Matkovic, Ana; Merritt, David; Miller, Bryan W.; Miller, Neal A.; Mobasher, Bahram; Mouhcine, Mustapha; Okamura, Sadanori; Percival, Sue; Phillipps, Steven; Poggianti, Bianca M.; Price, James; Sharples, Ray M.; Tully, R. Brent; Valentijn, Edwin

    The Coma cluster, Abell 1656, was the target of an HST-ACS Treasury program designed for deep imaging in the F475W and F814W passbands. Although our survey was interrupted by the ACS instrument failure in early 2007, the partially completed survey still covers ~50% of the core high-density region in

  11. The Fornax Cluster VLT Spectroscopic Survey II - Planetary Nebulae kinematics within 200 kpc of the cluster core

    Science.gov (United States)

    Spiniello, C.; Napolitano, N. R.; Arnaboldi, M.; Tortora, C.; Coccato, L.; Capaccioli, M.; Gerhard, O.; Iodice, E.; Spavone, M.; Cantiello, M.; Peletier, R.; Paolillo, M.; Schipani, P.

    2018-06-01

    We present the largest and most spatially extended planetary nebulae (PNe) catalogue ever obtained for the Fornax cluster. We measured velocities of 1452 PNe out to 200 kpc in the cluster core using a counter-dispersed slitless spectroscopic technique with data from FORS2 on the Very Large Telescope (VLT). With such an extended spatial coverage, we can study separately the stellar haloes of some of the cluster main galaxies and the intracluster light. In this second paper of the Fornax Cluster VLT Spectroscopic Survey, we identify and classify the emission-line sources, describe the method to select PNe, and calculate their coordinates and velocities from the dispersed slitless images. From the PN 2D velocity map, we identify stellar streams that are possibly tracing the gravitational interaction of NGC 1399 with NGC 1404 and NGC 1387. We also present the velocity dispersion profile out to ˜200 kpc radii, which shows signatures of a superposition of the bright central galaxy and the cluster potential, with the latter clearly dominating the regions outside R ˜ 1000 arcsec (˜100 kpc).

  12. The statistics of foreshock cavities: results of a Cluster survey

    OpenAIRE

    L. Billingham; S. J. Schwartz; D. G. Sibeck

    2008-01-01

    We use Cluster magnetic field, thermal ion, and energetic particle observations upstream of the Earth's bow shock to investigate the occurrence patterns of foreshock cavities. Such cavities are thought to form when bundles of magnetic field connect to the quasi-parallel bow shock. Shock-processed suprathermal ions can then stream along the field, back against the flow of the solar wind. These suprathermals enhance the pressure on shock-connected field lines causing them to expand into th...

  13. THE MASSIVE AND DISTANT CLUSTERS OF WISE SURVEY. II. INITIAL SPECTROSCOPIC CONFIRMATION OF z ∼ 1 GALAXY CLUSTERS SELECTED FROM 10,000 deg2

    International Nuclear Information System (INIS)

    Stanford, S. A.; Gonzalez, Anthony H.; Gettings, Daniel P.; Brodwin, Mark; Eisenhardt, Peter R. M.; Stern, Daniel; Wylezalek, Dominika

    2014-01-01

    We present optical and infrared imaging and optical spectroscopy of galaxy clusters which were identified as part of an all-sky search for high-redshift galaxy clusters, the Massive and Distant Clusters of WISE Survey (MaDCoWS). The initial phase of MaDCoWS combined infrared data from the all-sky data release of the Wide-field Infrared Survey Explorer (WISE) with optical data from the Sloan Digital Sky Survey to select probable z ∼ 1 clusters of galaxies over an area of 10,000 deg 2 . Our spectroscopy confirms 19 new clusters at 0.7 < z < 1.3, half of which are at z > 1, demonstrating the viability of using WISE to identify high-redshift galaxy clusters. The next phase of MaDCoWS will use the greater depth of the AllWISE data release to identify even higher redshift cluster candidates

  14. THE XMM CLUSTER SURVEY: THE STELLAR MASS ASSEMBLY OF FOSSIL GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Craig D.; Miller, Christopher J. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Richards, Joseph W.; Deadman, Paul-James [Center for Time Domain Informatics, University of California, Berkeley, CA 94720 (United States); Lloyd-Davies, E. J.; Kathy Romer, A.; Mehrtens, Nicola; Liddle, Andrew R. [Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom); Hoyle, Ben [Institute of Sciences of the Cosmos (ICCUB) and IEEC, Physics Department, University of Barcelona, Barcelona 08024 (Spain); Hilton, Matt [Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban 4000 (South Africa); Stott, John P.; Capozzi, Diego; Collins, Chris A. [Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom); Sahlen, Martin [Oskar Klein Centre for Cosmoparticle Physics, Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden); Stanford, S. Adam [Physics Department, University of California, Davis, CA 95616 (United States); Viana, Pedro T. P., E-mail: craigha@umich.edu [Centro de Astrofisica da Universidade do Porto, Rua das Estrelas, 4150-762 Porto (Portugal)

    2012-06-10

    This paper presents both the result of a search for fossil systems (FSs) within the XMM Cluster Survey and the Sloan Digital Sky Survey and the results of a study of the stellar mass assembly and stellar populations of their fossil galaxies. In total, 17 groups and clusters are identified at z < 0.25 with large magnitude gaps between the first and fourth brightest galaxies. All the information necessary to classify these systems as fossils is provided. For both groups and clusters, the total and fractional luminosity of the brightest galaxy is positively correlated with the magnitude gap. The brightest galaxies in FSs (called fossil galaxies) have stellar populations and star formation histories which are similar to normal brightest cluster galaxies (BCGs). However, at fixed group/cluster mass, the stellar masses of the fossil galaxies are larger compared to normal BCGs, a fact that holds true over a wide range of group/cluster masses. Moreover, the fossil galaxies are found to contain a significant fraction of the total optical luminosity of the group/cluster within 0.5 R{sub 200}, as much as 85%, compared to the non-fossils, which can have as little as 10%. Our results suggest that FSs formed early and in the highest density regions of the universe and that fossil galaxies represent the end products of galaxy mergers in groups and clusters.

  15. A Keck/DEIMOS spectroscopic survey of the faint M31 satellites AndIX, AndXI, AndXII and AndXIII†

    Science.gov (United States)

    Collins, M. L. M.; Chapman, S. C.; Irwin, M. J.; Martin, N. F.; Ibata, R. A.; Zucker, D. B.; Blain, A.; Ferguson, A. M. N.; Lewis, G. F.; McConnachie, A. W.; Peñarrubia, J.

    2010-10-01

    We present the first spectroscopic analysis of the faint M31 satellite galaxies, AndXI and AndXIII, as well as a re-analysis of existing spectroscopic data for two further faint companions, AndIX (correcting for an error in earlier geometric modelling that caused a misclassification of member stars in previous work) and AndXII. By combining data obtained using the Deep Imaging Multi-Object Spectrograph (DEIMOS) mounted on the Keck II telescope with deep photometry from the Suprime-Cam instrument on Subaru, we have identified the most probable members for each of the satellites based on their radial velocities (precise to several down to i ~ 22), distance from the centre of the dwarf spheroidal galaxies (dSphs) and their photometric [Fe/H]. Using both the photometric and spectroscopic data, we have also calculated global properties for the dwarfs, such as systemic velocities, metallicities and half-light radii. We find each dwarf to be very metal poor ([Fe/H] ~ -2 both photometrically and spectroscopically, from their stacked spectrum), and as such, they continue to follow the luminosity-metallicity relationship established with brighter dwarfs. We are unable to resolve dispersion for AndXI due to small sample size and low signal-to-noise ratio, but we set a 1σ upper limit of σv financial support of the W.M. Keck Foundation. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. ‡ E-mail: mlmc2@ast.cam.ac.uk

  16. New VVV Survey Globular Cluster Candidates in the Milky Way Bulge

    Energy Technology Data Exchange (ETDEWEB)

    Minniti, Dante; Gómez, Matías [Departamento de Física, Facultad de Ciencias Exactas, Universidad Andrés Bello, Av. Fernandez Concha 700, Las Condes, Santiago (Chile); Geisler, Douglas; Fernández-Trincado, Jose G. [Departamento de Astronomía, Casilla 160-C, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Alonso-García, Javier; Beamín, Juan Carlos; Borissova, Jura; Catelan, Marcio; Ramos, Rodrigo Contreras; Kurtev, Radostin; Pullen, Joyce [Instituto Milenio de Astrofísica, Santiago (Chile); Palma, Tali; Clariá, Juan J. [Observatorio Astronómico, Universidad Nacional de Córdoba, Laprida 854, Córdoba (Argentina); Cohen, Roger E. [Space Telescope Science Institute, 2700 San Martin Drive, Baltimore (United States); Dias, Bruno [European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago (Chile); Hempel, Maren [Pontificia Universidad Católica de Chile, Instituto de Astrofísica, Av. Vicuña Mackenna 4860, Santiago (Chile); Ivanov, Valentin D. [European Southern Observatory, Karl-Schwarszchild-Str. 2, D-85748 Garching bei Muenchen (Germany); Lucas, Phillip W. [Dept. of Astronomy, University of Hertfordshire, Hertfordshire (United Kingdom); Moni-Bidin, Christian; Alegría, Sebastian Ramírez [Instituto de Astronomía, Universidad Católica del Norte, Antofagasta (Chile); and others

    2017-11-10

    It is likely that a number of Galactic globular clusters remain to be discovered, especially toward the Galactic bulge. High stellar density combined with high and differential interstellar reddening are the two major problems for finding globular clusters located toward the bulge. We use the deep near-IR photometry of the VISTA Variables in the Vía Láctea (VVV) Survey to search for globular clusters projected toward the Galactic bulge, and hereby report the discovery of 22 new candidate globular clusters. These objects, detected as high density regions in our maps of bulge red giants, are confirmed as globular cluster candidates by their color–magnitude diagrams. We provide their coordinates as well as their near-IR color–magnitude diagrams, from which some basic parameters are derived, such as reddenings and heliocentric distances. The color–magnitude diagrams reveal well defined red giant branches in all cases, often including a prominent red clump. The new globular cluster candidates exhibit a variety of extinctions (0.06 < A {sub Ks} < 2.77) and distances (5.3 < D < 9.5 kpc). We also classify the globular cluster candidates into 10 metal-poor and 12 metal-rich clusters, based on the comparison of their color–magnitude diagrams with those of known globular clusters also observed by the VVV Survey. Finally, we argue that the census for Galactic globular clusters still remains incomplete, and that many more candidate globular clusters (particularly the low luminosity ones) await to be found and studied in detail in the central regions of the Milky Way.

  17. The statistics of foreshock cavities: results of a Cluster survey

    Directory of Open Access Journals (Sweden)

    L. Billingham

    2008-11-01

    Full Text Available We use Cluster magnetic field, thermal ion, and energetic particle observations upstream of the Earth's bow shock to investigate the occurrence patterns of foreshock cavities. Such cavities are thought to form when bundles of magnetic field connect to the quasi-parallel bow shock. Shock-processed suprathermal ions can then stream along the field, back against the flow of the solar wind. These suprathermals enhance the pressure on shock-connected field lines causing them to expand into the surrounding ambient solar wind plasma. Foreshock cavities exhibit depressions in magnetic field magnitude and thermal ion density, associated with enhanced fluxes of energetic ions. We find typical cavity duration to be few minutes with interior densities and magnetic field magnitudes dropping to ~60% of those in the surrounding solar wind. Cavities are found to occur preferentially in fast, moderate magnetic field strength solar wind streams. Cavities are observed in all parts of the Cluster orbit upstream of the bow shock. When localised in a coordinate system organised by the underlying physical processes in the foreshock, there is a systematic change in foreshock cavity location with IMF cone angle. At low (high cone angles foreshock cavities are observed outside (inside the expected upstream boundary of the intermediate ion foreshock.

  18. The statistics of foreshock cavities: results of a Cluster survey

    Directory of Open Access Journals (Sweden)

    L. Billingham

    2008-11-01

    Full Text Available We use Cluster magnetic field, thermal ion, and energetic particle observations upstream of the Earth's bow shock to investigate the occurrence patterns of foreshock cavities. Such cavities are thought to form when bundles of magnetic field connect to the quasi-parallel bow shock. Shock-processed suprathermal ions can then stream along the field, back against the flow of the solar wind. These suprathermals enhance the pressure on shock-connected field lines causing them to expand into the surrounding ambient solar wind plasma. Foreshock cavities exhibit depressions in magnetic field magnitude and thermal ion density, associated with enhanced fluxes of energetic ions. We find typical cavity duration to be few minutes with interior densities and magnetic field magnitudes dropping to ~60% of those in the surrounding solar wind. Cavities are found to occur preferentially in fast, moderate magnetic field strength solar wind streams. Cavities are observed in all parts of the Cluster orbit upstream of the bow shock. When localised in a coordinate system organised by the underlying physical processes in the foreshock, there is a systematic change in foreshock cavity location with IMF cone angle. At low (high cone angles foreshock cavities are observed outside (inside the expected upstream boundary of the intermediate ion foreshock.

  19. A NEW DISTANT MILKY WAY GLOBULAR CLUSTER IN THE PAN-STARRS1 3π SURVEY

    International Nuclear Information System (INIS)

    Laevens, Benjamin P. M.; Martin, Nicolas F.; Sesar, Branimir; Rix, Hans-Walter; Schlafly, Edward F.; Bernard, Edouard J.; Ferguson, Annette M. N.; Slater, Colin T.; Bell, Eric F.; Burgett, William S.; Chambers, Kenneth C.; Denneau, Larry; Kaiser, Nicholas; Kudritzki, Rolf-Peter; Magnier, Eugene A.; Morgan, Jeffrey S.; Sweeney, William E.; Draper, Peter W.; Metcalfe, Nigel; Price, Paul A.

    2014-01-01

    We present a new satellite in the outer halo of the Galaxy, the first Milky Way satellite found in the stacked photometric catalog of the Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1) Survey. From follow-up photometry obtained with WFI on the MPG/ESO 2.2 m telescope, we argue that the object, located at a heliocentric distance of 145 ± 17 kpc, is the most distant Milky Way globular cluster yet known. With a total magnitude of M V = –4.3 ± 0.2 and a half-light radius of 20 ± 2 pc, it shares the properties of extended globular clusters found in the outer halo of our Galaxy and the Andromeda galaxy. The discovery of this distant cluster shows that the full spatial extent of the Milky Way globular cluster system has not yet been fully explored

  20. The Open Cluster Chemical Abundances and Mapping (OCCAM) Survey: Current Status

    Science.gov (United States)

    Frinchaboy, Peter; O'Connell, Julia; Donor, John; Cunha, Katia; Thompson, Benjamin; Melendez, Matthew; Shetrone, Matthew; Zasowski, Gail; Majewski, Steven R.; APOGEE TEAM

    2018-01-01

    The Open Cluster Chemical Analysis and Mapping (OCCAM) survey aims to produce a comprehensive, uniform, infrared-based data set forhundreds of open clusters, and constrain key Galactic dynamical and chemical parameters using the SDSS/APOGEE survey and follow-up from the McDonald Observatory Otto Struve 2.1-m telescope and Sandiford Cass Echelle Spectrograph (R ~ 60,000). We report on multi-element radial abundance gradients obtained from a sample of over 30 disk open clusters. The APOGEE chemical abundances were derived automatically by the ASPCAP pipeline and these are part of the SDSS IV Data Release 14, optical follow-up were analyzed using equivalent width analysis and spectral synthesis. We present the current open cluster sample that spans a significant range in age allowing exploration of the evolution of the Galactic abundance gradients. This work is supported by an NSF AAG grants AST-1311835 & AST-1715662.

  1. SPATIAL ANISOTROPY OF GALAXY KINEMATICS IN SLOAN DIGITAL SKY SURVEY GALAXY CLUSTERS

    International Nuclear Information System (INIS)

    Skielboe, Andreas; Wojtak, Radosław; Pedersen, Kristian; Rozo, Eduardo; Rykoff, Eli S.

    2012-01-01

    Measurements of galaxy cluster kinematics are important in understanding the dynamical state and evolution of clusters of galaxies, as well as constraining cosmological models. While it is well established that clusters exhibit non-spherical geometries, evident in the distribution of galaxies on the sky, azimuthal variations of galaxy kinematics within clusters have yet to be observed. Here we measure the azimuthal dependence of the line-of-sight velocity dispersion profile in a stacked sample of 1743 galaxy clusters from the Sloan Digital Sky Survey (SDSS). The clusters are drawn from the SDSS DR8 redMaPPer catalog. We find that the line-of-sight velocity dispersion of galaxies lying along the major axis of the central galaxy is larger than those that lie along the minor axis. This is the first observational detection of anisotropic kinematics of galaxies in clusters. We show that the result is consistent with predictions from numerical simulations. Furthermore, we find that the degree of projected anisotropy is strongly dependent on the line-of-sight orientation of the galaxy cluster, opening new possibilities for assessing systematics in optical cluster finding.

  2. X-ray and optical substructures of the DAFT/FADA survey clusters

    Science.gov (United States)

    Guennou, L.; Durret, F.; Adami, C.; Lima Neto, G. B.

    2013-04-01

    We have undertaken the DAFT/FADA survey with the double aim of setting constraints on dark energy based on weak lensing tomography and of obtaining homogeneous and high quality data for a sample of 91 massive clusters in the redshift range 0.4-0.9 for which there were HST archive data. We have analysed the XMM-Newton data available for 42 of these clusters to derive their X-ray temperatures and luminosities and search for substructures. Out of these, a spatial analysis was possible for 30 clusters, but only 23 had deep enough X-ray data for a really robust analysis. This study was coupled with a dynamical analysis for the 26 clusters having at least 30 spectroscopic galaxy redshifts in the cluster range. Altogether, the X-ray sample of 23 clusters and the optical sample of 26 clusters have 14 clusters in common. We present preliminary results on the coupled X-ray and dynamical analyses of these 14 clusters.

  3. Too Little, Too Late: How the Tidal Evolution of Hot Jupiters Affects Transit Surveys of Clusters

    Science.gov (United States)

    Debes, John H.; Jackson, Brian

    2010-01-01

    The tidal evolution of hot Jupiters may change the efficiency of transit surveys of stellar clusters. The orbital decay that hot Jupiters suffer may result in their destruction, leaving fewer transiting planets in older clusters. We calculate the impact tidal evolution has for different assumed stellar populations, including that of 47 Tuc, a globular cluster that was the focus of an intense HST search for transits. We find that in older clusters one expects to detect fewer transiting planets by a factor of two for surveys sensitive to Jupiter-like planets in orbits out to 0.5 AU, and up to a factor of 25 for surveys sensitive to Jupiter-like planets in orbits out to 0.08 AU. Additionally, tidal evolution affects the distribution of transiting planets as a function of semi-major axis, producing larger orbital period gaps for transiting planets as the age of the cluster increases. Tidal evolution can explain the lack of detected exoplanets in 47 Tuc without invoking other mechanisms. Four open clusters residing within the Kepler fields of view have ages that span 0.4-8 Gyr-if Kepler can observe a significant number of planets in these clusters, it will provide key tests for our tidal evolution hypothesis. Finally, our results suggest that observers wishing to discover transiting planets in clusters must have sufficient accuracy to detect lower mass planets, search larger numbers of cluster members, or have longer observation windows to be confident that a significant number of transits will occur for a population of stars.

  4. THE JCMT GOULD BELT SURVEY: DENSE CORE CLUSTERS IN ORION A

    Energy Technology Data Exchange (ETDEWEB)

    Lane, J.; Kirk, H.; Johnstone, D.; Mairs, S.; Francesco, J. Di [NRC Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC, V9E 2E7 (Canada); Sadavoy, S. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Hatchell, J. [Physics and Astronomy, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom); Berry, D. S. [East Asian Observatory, 660 N. A‘ohōkū Place, University Park, Hilo, Hawaii 96720 (United States); Jenness, T. [Joint Astronomy Centre, 660 N. A‘ohōkū Place, University Park, Hilo, Hawaii 96720 (United States); Hogerheijde, M. R. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Ward-Thompson, D. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston, Lancashire, PR1 2HE (United Kingdom); Collaboration: JCMT Gould Belt Survey Team

    2016-12-10

    The Orion A molecular cloud is one of the most well-studied nearby star-forming regions, and includes regions of both highly clustered and more dispersed star formation across its full extent. Here, we analyze dense, star-forming cores identified in the 850 and 450 μ m SCUBA-2 maps from the JCMT Gould Belt Legacy Survey. We identify dense cores in a uniform manner across the Orion A cloud and analyze their clustering properties. Using two independent lines of analysis, we find evidence that clusters of dense cores tend to be mass segregated, suggesting that stellar clusters may have some amount of primordial mass segregation already imprinted in them at an early stage. We also demonstrate that the dense core clusters have a tendency to be elongated, perhaps indicating a formation mechanism linked to the filamentary structure within molecular clouds.

  5. THE JCMT GOULD BELT SURVEY: DENSE CORE CLUSTERS IN ORION A

    International Nuclear Information System (INIS)

    Lane, J.; Kirk, H.; Johnstone, D.; Mairs, S.; Francesco, J. Di; Sadavoy, S.; Hatchell, J.; Berry, D. S.; Jenness, T.; Hogerheijde, M. R.; Ward-Thompson, D.

    2016-01-01

    The Orion A molecular cloud is one of the most well-studied nearby star-forming regions, and includes regions of both highly clustered and more dispersed star formation across its full extent. Here, we analyze dense, star-forming cores identified in the 850 and 450 μ m SCUBA-2 maps from the JCMT Gould Belt Legacy Survey. We identify dense cores in a uniform manner across the Orion A cloud and analyze their clustering properties. Using two independent lines of analysis, we find evidence that clusters of dense cores tend to be mass segregated, suggesting that stellar clusters may have some amount of primordial mass segregation already imprinted in them at an early stage. We also demonstrate that the dense core clusters have a tendency to be elongated, perhaps indicating a formation mechanism linked to the filamentary structure within molecular clouds.

  6. Innovation in Industrial Clusters: a Survey of Footwear Companies in Brazil

    Directory of Open Access Journals (Sweden)

    Hélcio Martins Tristão

    2013-09-01

    Full Text Available The aim of this study is to characterize the relationships in innovation and business clustering processes in the productive chain of small and medium enterprises (SME of Brazil. The object of study are SMEs the local procuctive cluster of the shoes in Franca, State of São Paulo. The conceptual model developed is based on the following constructs: vertical integration, innovation and characteristics of the cluster, and it is focused on identifying the agents that act predominantly in product innovation processes in the cluster. A survey was conducted. It was found that there is cooperation between the companies in the productive arrangement studied, and that shoe manufacturers are those who, predominantly, stimulate innovation within the cluster.

  7. THE HUBBLE SPACE TELESCOPE UV LEGACY SURVEY OF GALACTIC GLOBULAR CLUSTERS. VIII. PRELIMINARY PUBLIC CATALOG RELEASE

    Energy Technology Data Exchange (ETDEWEB)

    Soto, M.; Bellini, A.; Anderson, J.; Van der Marel, R. P.; Brown, T. M. [Space Telescope Science Institute, San Martin Drive 3700, Baltimore, MD 21218 (United States); Piotto, G.; Granata, V.; Ortolani, S.; Nardiello, D. [Dipartimento di Fisica e Astronomia Galileo Galilei, Università di Padova, Vicolo dell’Osservatorio 3, I-35122 Padova (Italy); Bedin, L. R. [INAF-Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy); Milone, A. P. [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston, ACT, 2611 (Australia); Cool, A. M. [Department of Physics and Astronomy, San Francisco State University, 1600 Holloway Avenue, San Francisco, CA 94132 (United States); King, I. R. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195-1580 (United States); Sarajedini, A. [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Cassisi, S. [Osservatorio Astronomico di Teramo, Via Mentore Maggini s.n.c., I-64100 Teramo (Italy); Aparicio, A.; Hidalgo, S., E-mail: mario.soto@uda.cl [Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Canary Islands (Spain)

    2017-01-01

    The Hubble Space Telescope (HST) UV Legacy Survey of Galactic Globular Clusters (GO-13297) has been specifically designed to complement the existing F606W and F814W observations of the Advanced Camera for Surveys (ACS) Globular Cluster Survey (GO-10775) by observing the most accessible 47 of the previous survey’s 65 clusters in three WFC3/UVIS filters F275W, F336W, and F438W. The new survey also adds super-solar metallicity open cluster NGC 6791 to increase the metallicity diversity. The combined survey provides a homogeneous 5-band data set that can be used to pursue a broad range of scientific investigations. In particular, the chosen UV filters allow the identification of multiple stellar populations by targeting the regions of the spectrum that are sensitive to abundance variations in C, N, and O. In order to provide the community with uniform preliminary catalogs, we have devised an automated procedure that performs high-quality photometry on the new UV observations (along with similar observations of seven other programs in the archive). This procedure finds and measures the potential sources on each individual exposure using library point-spread functions and cross-correlates these observations with the original ACS-Survey catalog. The catalog of 57 clusters we publish here will be useful to identify stars in the different stellar populations, in particular for spectroscopic follow-up. Eventually, we will construct a more sophisticated catalog and artificial-star tests based on an optimal reduction of the UV survey data, but the catalogs presented here give the community the chance to make early use of this HST Treasury survey.

  8. Source selection for cluster weak lensing measurements in the Hyper Suprime-Cam survey

    Science.gov (United States)

    Medezinski, Elinor; Oguri, Masamune; Nishizawa, Atsushi J.; Speagle, Joshua S.; Miyatake, Hironao; Umetsu, Keiichi; Leauthaud, Alexie; Murata, Ryoma; Mandelbaum, Rachel; Sifón, Cristóbal; Strauss, Michael A.; Huang, Song; Simet, Melanie; Okabe, Nobuhiro; Tanaka, Masayuki; Komiyama, Yutaka

    2018-03-01

    We present optimized source galaxy selection schemes for measuring cluster weak lensing (WL) mass profiles unaffected by cluster member dilution from the Subaru Hyper Suprime-Cam Strategic Survey Program (HSC-SSP). The ongoing HSC-SSP survey will uncover thousands of galaxy clusters to z ≲ 1.5. In deriving cluster masses via WL, a critical source of systematics is contamination and dilution of the lensing signal by cluster members, and by foreground galaxies whose photometric redshifts are biased. Using the first-year CAMIRA catalog of ˜900 clusters with richness larger than 20 found in ˜140 deg2 of HSC-SSP data, we devise and compare several source selection methods, including selection in color-color space (CC-cut), and selection of robust photometric redshifts by applying constraints on their cumulative probability distribution function (P-cut). We examine the dependence of the contamination on the chosen limits adopted for each method. Using the proper limits, these methods give mass profiles with minimal dilution in agreement with one another. We find that not adopting either the CC-cut or P-cut methods results in an underestimation of the total cluster mass (13% ± 4%) and the concentration of the profile (24% ± 11%). The level of cluster contamination can reach as high as ˜10% at R ≈ 0.24 Mpc/h for low-z clusters without cuts, while employing either the P-cut or CC-cut results in cluster contamination consistent with zero to within the 0.5% uncertainties. Our robust methods yield a ˜60 σ detection of the stacked CAMIRA surface mass density profile, with a mean mass of M200c = [1.67 ± 0.05(stat)] × 1014 M⊙/h.

  9. The GALAH survey: chemical tagging of star clusters and new members in the Pleiades

    Science.gov (United States)

    Kos, Janez; Bland-Hawthorn, Joss; Freeman, Ken; Buder, Sven; Traven, Gregor; De Silva, Gayandhi M.; Sharma, Sanjib; Asplund, Martin; Duong, Ly; Lin, Jane; Lind, Karin; Martell, Sarah; Simpson, Jeffrey D.; Stello, Dennis; Zucker, Daniel B.; Zwitter, Tomaž; Anguiano, Borja; Da Costa, Gary; D'Orazi, Valentina; Horner, Jonathan; Kafle, Prajwal R.; Lewis, Geraint; Munari, Ulisse; Nataf, David M.; Ness, Melissa; Reid, Warren; Schlesinger, Katie; Ting, Yuan-Sen; Wyse, Rosemary

    2018-02-01

    The technique of chemical tagging uses the elemental abundances of stellar atmospheres to 'reconstruct' chemically homogeneous star clusters that have long since dispersed. The GALAH spectroscopic survey - which aims to observe one million stars using the Anglo-Australian Telescope - allows us to measure up to 30 elements or dimensions in the stellar chemical abundance space, many of which are not independent. How to find clustering reliably in a noisy high-dimensional space is a difficult problem that remains largely unsolved. Here, we explore t-distributed stochastic neighbour embedding (t-SNE) - which identifies an optimal mapping of a high-dimensional space into fewer dimensions - whilst conserving the original clustering information. Typically, the projection is made to a 2D space to aid recognition of clusters by eye. We show that this method is a reliable tool for chemical tagging because it can: (i) resolve clustering in chemical space alone, (ii) recover known open and globular clusters with high efficiency and low contamination, and (iii) relate field stars to known clusters. t-SNE also provides a useful visualization of a high-dimensional space. We demonstrate the method on a data set of 13 abundances measured in the spectra of 187 000 stars by the GALAH survey. We recover seven of the nine observed clusters (six globular and three open clusters) in chemical space with minimal contamination from field stars and low numbers of outliers. With chemical tagging, we also identify two Pleiades supercluster members (which we confirm kinematically), one as far as 6° - one tidal radius away from the cluster centre.

  10. The VMC survey. XI. Radial stellar population gradients in the galactic globular cluster 47 Tucanae

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chengyuan; De Grijs, Richard [Kavli Institute for Astronomy and Astrophysics, Peking University, Yi He Yuan Lu 5, Hai Dian District, Beijing 100871 (China); Deng, Licai [Key Laboratory for Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100012 (China); Rubele, Stefano; Girardi, Leo; Gullieuszik, Marco [INAF-Osservatorio Astronomico di Padova, vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Wang, Chuchu [Department of Astronomy, Peking University, Yi He Yuan Lu 5, Hai Dian District, Beijing 100871 (China); Bekki, Kenji; For, Bi-Qing [ICRAR M468, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia); Cioni, Maria-Rosa L. [Department of Physics, Astronomy, and Mathematics, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom); Clementini, Gisella [INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Emerson, Jim [Astronomy Unit, School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Groenewegen, Martin A. T. [Royal Observatory of Belgium, Ringlaan 3, 1180 Ukkel (Belgium); Guandalini, Roald [Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D 2401, 3001 Leuven (Belgium); Marconi, Marcella; Ripepi, Vincenzo [INAF-Osservatorio Astronomico di Capodimonte, via Moiariello 16, I-80131 Naples (Italy); Piatti, Andrés E. [Observatorio Astrońomico, Universidad Nacional de Córdoba, Laprida 854, 5000 Córdoba (Argentina); Van Loon, Jacco Th., E-mail: joshuali@pku.edu.cn, E-mail: grijs@pku.edu.cn [Astrophysics Group, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom)

    2014-07-20

    We present a deep near-infrared color-magnitude diagram of the Galactic globular cluster 47 Tucanae, obtained with the Visible and Infrared Survey Telescope for Astronomy (VISTA) as part of the VISTA near-infrared Y, J, K{sub s} survey of the Magellanic System (VMC). The cluster stars comprising both the subgiant and red giant branches exhibit apparent, continuous variations in color-magnitude space as a function of radius. Subgiant branch stars at larger radii are systematically brighter than their counterparts closer to the cluster core; similarly, red-giant-branch stars in the cluster's periphery are bluer than their more centrally located cousins. The observations can very well be described by adopting an age spread of ∼0.5 Gyr as well as radial gradients in both the cluster's helium abundance (Y) and metallicity (Z), which change gradually from (Y = 0.28, Z = 0.005) in the cluster core to (Y = 0.25, Z = 0.003) in its periphery. We conclude that the cluster's inner regions host a significant fraction of second-generation stars, which decreases with increasing radius; the stellar population in the 47 Tuc periphery is well approximated by a simple stellar population.

  11. Substructures in DAFT/FADA survey clusters based on XMM and optical data

    Science.gov (United States)

    Durret, F.; DAFT/FADA Team

    2014-07-01

    The DAFT/FADA survey was initiated to perform weak lensing tomography on a sample of 90 massive clusters in the redshift range [0.4,0.9] with HST imaging available. The complementary deep multiband imaging constitutes a high quality imaging data base for these clusters. In X-rays, we have analysed the XMM-Newton and/or Chandra data available for 32 clusters, and for 23 clusters we fit the X-ray emissivity with a beta-model and subtract it to search for substructures in the X-ray gas. This study was coupled with a dynamical analysis for the 18 clusters with at least 15 spectroscopic galaxy redshifts in the cluster range, based on a Serna & Gerbal (SG) analysis. We detected ten substructures in eight clusters by both methods (X-rays and SG). The percentage of mass included in substructures is found to be roughly constant with redshift, with values of 5-15%. Most of the substructures detected both in X-rays and with the SG method are found to be relatively recent infalls, probably at their first cluster pericenter approach.

  12. Optimizing measurements of cluster velocities and temperatures for CCAT-prime and future surveys

    Science.gov (United States)

    Mittal, Avirukt; de Bernardis, Francesco; Niemack, Michael D.

    2018-02-01

    Galaxy cluster velocity correlations and mass distributions are sensitive probes of cosmology and the growth of structure. Upcoming microwave surveys will enable extraction of velocities and temperatures from many individual clusters for the first time. We forecast constraints on peculiar velocities, electron temperatures, and optical depths of galaxy clusters obtainable with upcoming multi-frequency measurements of the kinematic, thermal, and relativistic Sunyaev-Zeldovich effects. The forecasted constraints are compared for different measurement configurations with frequency bands between 90 GHz and 1 THz, and for different survey strategies for the 6-meter CCAT-prime telescope. We study methods for improving cluster constraints by removing emission from dusty star forming galaxies, and by using X-ray temperature priors from eROSITA. Cluster constraints are forecast for several model cluster masses. A sensitivity optimization for seven frequency bands is presented for a CCAT-prime first light instrument and a next generation instrument that takes advantage of the large optical throughput of CCAT-prime. We find that CCAT-prime observations are expected to enable measurement and separation of the SZ effects to characterize the velocity, temperature, and optical depth of individual massive clusters (~1015 Msolar). Submillimeter measurements are shown to play an important role in separating these components from dusty galaxy contamination. Using a modular instrument configuration with similar optical throughput for each detector array, we develop a rule of thumb for the number of detector arrays desired at each frequency to optimize extraction of these signals. Our results are relevant for a future "Stage IV" cosmic microwave background survey, which could enable galaxy cluster measurements over a larger range of masses and redshifts than will be accessible by other experiments.

  13. New open cluster candidates discovered in the XSTPS-GAC survey

    Science.gov (United States)

    Guo, Jin-Cheng; Zhang, Hua-Wei; Zhang, Hui-Hua; Liu, Xiao-Wei; Yuan, Hai-Bo; Huang, Yang; Wang, Song; Chen, Li; Zhao, Hai-Bin; Liu, Ji-Feng; Chen, Bing-Qiu; Xiang, Mao-Sheng; Tian, Zhi-Jia; Huo, Zhi-Ying; Wang, Chun

    2018-03-01

    The Xuyi Schmidt Telescope Photometric Survey of the Galactic Anti-center (XSTPS-GAC) is a photometric sky survey that covers nearly 6000 deg2 towards the Galactic Anti-center (GAC) in the g, r, i bands. Half of its survey field is located on the Galactic Anti-center disk, which makes XSTPS-GAC highly suitable to search for new open clusters in the GAC region. In this paper, we report new open cluster candidates discovered in this survey, as well as properties of these open cluster candidates, such as age, distance and reddening, derived by isochrone fitting in the color-magnitude diagram (CMD). These open cluster candidates are stellar density peaks detected in the star density maps by applying the method from Koposov et al. Each candidate is inspected in terms of its true color image composed from three XSTPS-GAC band images. Then its CMD is checked, in order to identify whether the central region stars have a clear isochrone-like trend differing from background stars. The parameters derived from isochrone fitting for these candidates are mainly based on three band photometry of XSTPS-GAC. Moreover, when these new candidates are able to be seen clearly in 2MASS data, their parameters are also derived based on the 2MASS (J – H, J) CMD. There are a total of 320 known open clusters rediscovered and 24 new open cluster candidates discovered in this work. Furthermore, the parameters of these new candidates, as well as another 11 previously known open clusters, are properly determined for the first time.

  14. The Hubble Space Telescope Medium Deep Survey Cluster Sample: Methodology and Data

    Science.gov (United States)

    Ostrander, E. J.; Nichol, R. C.; Ratnatunga, K. U.; Griffiths, R. E.

    1998-12-01

    We present a new, objectively selected, sample of galaxy overdensities detected in the Hubble Space Telescope Medium Deep Survey (MDS). These clusters/groups were found using an automated procedure that involved searching for statistically significant galaxy overdensities. The contrast of the clusters against the field galaxy population is increased when morphological data are used to search around bulge-dominated galaxies. In total, we present 92 overdensities above a probability threshold of 99.5%. We show, via extensive Monte Carlo simulations, that at least 60% of these overdensities are likely to be real clusters and groups and not random line-of-sight superpositions of galaxies. For each overdensity in the MDS cluster sample, we provide a richness and the average of the bulge-to-total ratio of galaxies within each system. This MDS cluster sample potentially contains some of the most distant clusters/groups ever detected, with about 25% of the overdensities having estimated redshifts z > ~0.9. We have made this sample publicly available to facilitate spectroscopic confirmation of these clusters and help more detailed studies of cluster and galaxy evolution. We also report the serendipitous discovery of a new cluster close on the sky to the rich optical cluster Cl l0016+16 at z = 0.546. This new overdensity, HST 001831+16208, may be coincident with both an X-ray source and a radio source. HST 001831+16208 is the third cluster/group discovered near to Cl 0016+16 and appears to strengthen the claims of Connolly et al. of superclustering at high redshift.

  15. Observation of the Coma cluster of galaxies with ROSAT during the all-sky survey

    Science.gov (United States)

    Briel, U. G.; Henry, J. P.; Boehringer, H.

    1992-01-01

    The Coma cluster of galaxies was observed with the position sensitive proportional counter (PSPC) during the ROSAT all sky survey. We find evidence for substructure in this cluster. Diffuse X-ray emission is detected from the regions of the NGC 4839 and 4911 subgroups at 6 percent and 1 percent of the total cluster emission respectively. There may be emission associated with the NGC 4874 and 4889 subgroups as well. The NGC 4839 group appears to be in the process of merging with the cluster. These X-ray data show that at least some of the groups previously found in projection are in fact physical objects possessing potential wells deep enough to trap their own X-ray gas. Because of the unlimited field of view of the all sky survey and the low background of the PSPC, we were able to measure the azimuthally averaged surface brightness of Coma out to approximately 100 arcmin, twice as far as was previously possible. Given the validity of our mass models, these new X-ray data imply that within 5/h(50) Mpc the binding mass of the Coma cluster is 1.8 +/- 0.6 x 10 exp 15/h(50) solar mass, and the fraction of cluster mass contained in hot gas is 0.30 +/- 0.14h(50) exp -3/2. Furthermore, the binding mass is more centrally concentrated than is the X-ray gas.

  16. Identifying Patient Attitudinal Clusters Associated with Asthma Control: The European REALISE Survey.

    Science.gov (United States)

    van der Molen, Thys; Fletcher, Monica; Price, David

    Asthma is a highly heterogeneous disease that can be classified into different clinical phenotypes, and treatment may be tailored accordingly. However, factors beyond purely clinical traits, such as patient attitudes and behaviors, can also have a marked impact on treatment outcomes. The objective of this study was to further analyze data from the REcognise Asthma and LInk to Symptoms and Experience (REALISE) Europe survey, to identify distinct patient groups sharing common attitudes toward asthma and its management. Factor analysis of respondent data (N = 7,930) from the REALISE Europe survey consolidated the 34 attitudinal variables provided by the study population into a set of 8 summary factors. Cluster analyses were used to identify patient clusters that showed similar attitudes and behaviors toward each of the 8 summary factors. Five distinct patient clusters were identified and named according to the key characteristics comprising that cluster: "Confident and self-managing," "Confident and accepting of their asthma," "Confident but dependent on others," "Concerned but confident in their health care professional (HCP)," and "Not confident in themselves or their HCP." Clusters showed clear variability in attributes such as degree of confidence in managing their asthma, use of reliever and preventer medication, and level of asthma control. The 5 patient clusters identified in this analysis displayed distinctly different personal attitudes that would require different approaches in the consultation room certainly for asthma but probably also for other chronic diseases. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  17. THE SLOAN BRIGHT ARCS SURVEY: TEN STRONG GRAVITATIONAL LENSING CLUSTERS AND EVIDENCE OF OVERCONCENTRATION

    Energy Technology Data Exchange (ETDEWEB)

    Wiesner, Matthew P. [Department of Physics, Northern Illinois University, DeKalb, IL 60115 (United States); Lin, Huan; Allam, Sahar S.; Annis, James; Buckley-Geer, Elizabeth J.; Diehl, H. Thomas; Kubik, Donna; Kubo, Jeffrey M.; Tucker, Douglas [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States)

    2012-12-10

    We describe 10 strong lensing galaxy clusters of redshift 0.26 {<=} z {<=} 0.56 that were found in the Sloan Digital Sky Survey. We present measurements of richness (N{sub 200}), mass (M{sub 200}), and velocity dispersion for the clusters. We find that in order to use the mass-richness relation from Johnston et al., which was established at mean redshift of 0.25, it is necessary to scale measured richness values up by 1.47. Using this scaling, we find richness values for these clusters to be in the range of 22 {<=} N{sub 200} {<=} 317 and mass values to be in the range of 1 Multiplication-Sign 10{sup 14} h {sup -1} M{sub Sun} {<=} M{sub 200} {<=} 30 Multiplication-Sign 10{sup 14} h {sup -1} M{sub Sun }. We also present measurements of Einstein radius, mass, and velocity dispersion for the lensing systems. The Einstein radii ({theta}{sub E}) are all relatively small, with 5.''4 {<=} {theta}{sub E} {<=} 13''. Finally, we consider if there is evidence that our clusters are more concentrated than {Lambda}CDM would predict. We find that six of our clusters do not show evidence of overconcentration, while four of our clusters do. We note a correlation between overconcentration and mass, as the four clusters showing evidence of overconcentration are all lower-mass clusters. For the four lowest mass clusters the average value of the concentration parameter c{sub 200} is 11.6, while for the six higher-mass clusters the average value of c{sub 200} is 4.4. {Lambda}CDM would place c{sub 200} between 3.4 and 5.7.

  18. Finding Clusters of Galaxies in the Sloan Digital Sky Survey using Voronoi Tessellation

    International Nuclear Information System (INIS)

    Rita S.J., Kim

    2001-01-01

    The Sloan Digital Sky Survey has obtained 450 square degrees of photometric scan data, in five bands (u', g', r', i', z'), which the authors use to identify clusters of galaxies. They illustrate how they do star-galaxy separation, and present a simple and elegant method of detecting over-densities in the galaxy distribution, using the Voronoi Tessellation

  19. Evaluating Tests of Virialization and Substructure Using Galaxy Clusters in the ORELSE Survey

    Science.gov (United States)

    Rumbaugh, N.; Lemaux, B. C.; Tomczak, A. R.; Shen, L.; Pelliccia, D.; Lubin, L. M.; Kocevski, D. D.; Wu, P.-F.; Gal, R. R.; Mei, S.; Fassnacht, C. D.; Squires, G. K.

    2018-05-01

    We evaluated the effectiveness of different indicators of cluster virialization using 12 large-scale structures in the ORELSE survey spanning from 0.7 distributions of galaxy populations, and centroiding differences. For comparison to a wide range of studies, we used two sets of tests: ones that did and did not use spectral energy distribution fitting to obtain rest-frame colours, stellar masses, and photometric redshifts of galaxies. Our results indicated that the difference between the stellar mass or light mean-weighted center and the X-ray center, as well as the projected offset of the most-massive/brightest cluster galaxy from other cluster centroids had the strongest correlations with scaling relation offsets, implying they are the most robust indicators of cluster virialization and can be used for this purpose when X-ray data is insufficiently deep for reliable LX and TX measurements.

  20. Counselor Education and Title IX: Current Perceptions and Questions

    Science.gov (United States)

    Welfare, Laura E.; Wagstaff, Jennifer; Haynes, Jenna R.

    2017-01-01

    This national survey of counselor educator perceptions of the Title IX requirement to report student disclosures of gender-based discrimination revealed the need for greater clarity about faculty strategies for serving counseling program students while upholding the federal law. The authors describe the recent expansion of the requirements and…

  1. The Next Generation Virgo Cluster Survey (NGVS). XXXII. A Search for Globular Cluster Substructures in the Virgo Galaxy Cluster Core

    Science.gov (United States)

    Powalka, Mathieu; Puzia, Thomas H.; Lançon, Ariane; Longobardi, Alessia; Peng, Eric W.; Duc, Pierre-Alain; Alamo-Martínez, Karla; Blakeslee, John P.; Côté, Patrick; Cuillandre, Jean-Charles; Durrell, Patrick; Eigenthaler, Paul; Ferrarese, Laura; Guhathakurta, Puragra; Gwyn, S. D. J.; Hudelot, Patrick; Liu, Chengze; Mei, Simona; Muñoz, Roberto P.; Roediger, Joel; Sánchez-Janssen, Rubén; Toloba, Elisa; Zhang, Hongxin

    2018-03-01

    Substructure in globular cluster (GC) populations around large galaxies is expected in galaxy formation scenarios that involve accretion or merger events, and it has been searched for using direct associations between GCs and structure in the diffuse galaxy light, or with GC kinematics. Here, we present a search for candidate substructures in the GC population around the Virgo cD galaxy M87 through the analysis of the spatial distribution of the GC colors. The study is based on a sample of ∼1800 bright GCs with high-quality u, g, r, i, z, K s photometry, selected to ensure a low contamination by foreground stars or background galaxies. The spectral energy distributions of the GCs are associated with formal estimates of age and metallicity, which are representative of its position in a 4D color space relative to standard single stellar population models. Dividing the sample into broad bins based on the relative formal ages, we observe inhomogeneities that reveal signatures of GC substructures. The most significant of these is a spatial overdensity of GCs with relatively young age labels, of diameter ∼0.°1 (∼30 kpc), located to the south of M87. The significance of this detection is larger than about 5σ after accounting for estimates of random and systematic errors. Surprisingly, no large Virgo galaxy is present in this area that could potentially host these GCs. But candidate substructures in the M87 halo with equally elusive hosts have been described based on kinematic studies in the past. The number of GC spectra available around M87 is currently insufficient to clarify the nature of the new candidate substructure.

  2. Legacy ExtraGalactic UV Survey with The Hubble Space Telescope: Stellar Cluster Catalogs and First Insights Into Cluster Formation and Evolution in NGC 628

    NARCIS (Netherlands)

    Adamo, A.; Ryon, J.E.; Messa, M.; Kim, H.; Grasha, K.; Cook, D.O.; Calzetti, D.; Lee, J.C.; Whitmore, B.C.; Elmegreen, B.G.; Ubeda, L.; Smith, L.J.; Bright, S.N.; Runnholm, A.; Andrews, J.E.; Fumagalli, M.; Gouliermis, D.A.; Kahre, L.; Nair, P.; Thilker, D.; Walterbos, R.; Wofford, A.; Aloisi, A.; Ashworth, G.; Brown, T.M.; Chandar, R.; Christian, C.; Cignoni, M.; Clayton, G.C.; Dale, D.A.; de Mink, S.E.; Dobbs, C.; Elmegreen, D.M.; Evans, A.S.; Gallagher III, J.S.; Grebel, E.K.; Herrero, A.; Hunter, D.A.; Johnson, K.E.; Kennicutt, R.C.; Krumholz, M.R.; Lennon, D.; Levay, K.; Martin, C.; Nota, A.; Östlin, G.; Pellerin, A.; Prieto, J.; Regan, M.W.; Sabbi, E.; Sacchi, E.; Schaerer, D.; Schiminovich, D.; Shabani, F.; Tosi, M.; Van Dyk, S.D.; Zackrisson, E.

    2017-01-01

    We report the large effort that is producing comprehensive high-level young star cluster (YSC) catalogs for a significant fraction of galaxies observed with the Legacy ExtraGalactic UV Survey (LEGUS) Hubble treasury program. We present the methodology developed to extract cluster positions, verify

  3. THE SNAPSHOT HUBBLE U-BAND CLUSTER SURVEY (SHUCS). I. SURVEY DESCRIPTION AND FIRST APPLICATION TO THE MIXED STAR CLUSTER POPULATION OF NGC 4041

    Energy Technology Data Exchange (ETDEWEB)

    Konstantopoulos, I. S. [Australian Astronomical Observatory, P.O. Box 915, North Ryde NSW 1670 (Australia); Smith, L. J. [Space Telescope Science Institute and European Space Agency, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Adamo, A. [Max-Planck-Institut for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Silva-Villa, E. [Departement de Physique, de Genie Physique et d' Optique, and Centre de Recherche en Astrophysique du Quebec (CRAQ), Universite Laval, Quebec (Canada); Gallagher, J. S.; Ryon, J. E. [Department of Astronomy, University of Wisconsin-Madison, 5534 Sterling, 475 North Charter Street, Madison WI 53706 (United States); Bastian, N. [Astrophysics Research Institute, Liverpool John Moores University, Egerton Wharf, Birkenhead, CH41 1LD (United Kingdom); Westmoquette, M. S. [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching bei Muenchen (Germany); Zackrisson, E. [Department of Astronomy, Stockholm University, Oscar Klein Centre, AlbaNova, Stockholm SE-106 91 (Sweden); Larsen, S. S. [Department of Astrophysics/IMAPP, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Weisz, D. R. [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Charlton, J. C., E-mail: iraklis@aao.gov.au [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2013-05-15

    We present the Snapshot Hubble U-band Cluster Survey (SHUCS), a project aimed at characterizing the star cluster populations of 10 nearby galaxies (d < 23 Mpc, half within Almost-Equal-To 12 Mpc) through new F336W (U-band equivalent) imaging from Wide Field Camera 3, and archival BVI-equivalent data with the Hubble Space Telescope. Completing the UBVI baseline reduces the age-extinction degeneracy of optical colors, thus enabling the measurement of reliable ages and masses for the thousands of clusters covered by our survey. The sample consists chiefly of face-on spiral galaxies at low inclination, in various degrees of isolation (isolated, in group, merging), and includes two active galactic nucleus hosts. This first paper outlines the survey itself, the observational datasets, the analysis methods, and presents a proof-of-concept study of the large-scale properties and star cluster population of NGC 4041, a massive SAbc galaxy at a distance of Almost-Equal-To 23 Mpc, and part of a small grouping of six giant members. We resolve two structural components with distinct stellar populations, a morphology more akin to merging and interacting systems. We also find strong evidence of a truncated, Schechter-type mass function, and a similarly segmented luminosity function. These results indicate that binning must erase much of the substructure present in the mass and luminosity functions, and might account for the conflicting reports on the intrinsic shape of these functions in the literature. We also note a tidal feature in the outskirts of the galaxy in Galaxy Evolution Explorer UV imaging, and follow it up with a comprehensive multi-wavelength study of NGC 4041 and its parent group. We deduce a minor merger as a likely cause of its segmented structure and the observed pattern of a radially decreasing star formation rate. We propose that combining the study of star cluster populations with broadband metrics is not only advantageous, but often easily achievable thorough

  4. OPEN CLUSTERS IN THE MILKY WAY OUTER DISK: NEWLY DISCOVERED AND UNSTUDIED CLUSTERS IN THE SPITZER GLIMPSE-360, CYG-X, AND SMOG SURVEYS

    International Nuclear Information System (INIS)

    Zasowski, G.; Beaton, R. L.; Hamm, K. K.; Majewski, S. R.; Patterson, R. J.; Babler, B.; Churchwell, E.; Meade, M.; Whitney, B. A.; Benjamin, R. A.; Watson, C.

    2013-01-01

    Open stellar clusters are extremely valuable probes of Galactic structure, star formation, kinematics, and chemical abundance patterns. Near-infrared (NIR) data have enabled the detection of hundreds of clusters hidden from optical surveys, and mid-infrared (MIR) data are poised to offer an even clearer view into the most heavily obscured parts of the Milky Way. We use new MIR images from the Spitzer GLIMPSE-360, Cyg-X, and SMOG surveys to visually identify a large number of open cluster candidates in the outer disk of the Milky Way (65° < l < 265°). Using NIR color-magnitude diagrams, stellar isochrones, and stellar reddening estimates, we derive cluster parameters (metallicity, distance, reddening) for those objects without previous identification and/or parameters in the literature. In total, we present coordinates and sizes of 20 previously unknown open cluster candidates; for 7 of these we also present metallicity, distance, and reddening values. In addition, we provide the first estimates of these values for nine clusters that had been previously cataloged. We compare our cluster sizes and other derived parameters to those in the open cluster catalog of Dias et al. and find strong similarities except for a higher mean reddening for our objects, which signifies our increased detection sensitivity in regions of high extinction. The results of this cluster search and analysis demonstrate the ability of MIR imaging and photometry to augment significantly the current census of open clusters in the Galaxy

  5. The HST/ACS Coma Cluster Survey : VI. Colour gradients in giant and dwarf early-type galaxies

    NARCIS (Netherlands)

    den Brok, M.; Peletier, R. F.; Valentijn, E. A.; Balcells, Marc; Carter, D.; Erwin, P.; Ferguson, H. C.; Goudfrooij, P.; Graham, A. W.; Hammer, D.; Lucey, J. R.; Trentham, N.; Guzman, R.; Hoyos, C.; Kleijn, G. Verdoes; Jogee, S.; Karick, A. M.; Marinova, I.; Mouhcine, M.; Weinzirl, T.

    Using deep, high-spatial-resolution imaging from the Hubble Space Telescope/Advanced Camera for Surveys (HST/ACS) Coma Cluster Treasury Survey, we determine colour profiles of early-type galaxies in the Coma cluster. From 176 galaxies brighter than M-F814W(AB) = -15 mag that are either

  6. The Open Cluster Chemical Abundances and Mapping (OCCAM) Survey: Galactic Neutron CaptureAbundance Gradients

    Science.gov (United States)

    O'Connell, Julia; Frinchaboy, Peter M.; Shetrone, Matthew D.; Melendez, Matthew; Cunha, Katia; Majewski, Steven R.; Zasowski, Gail; APOGEE Team

    2017-06-01

    The evolution of elements, as a function or age, throughout the Milky Way disk provides a key constraint for galaxy evolution models. In an effort to provide these constraints, we have conducted an investigation into the r- and s- process elemental abundances for a large sample of open clusters as part of an optical follow-up to the SDSS-III/APOGEE-1 survey. Stars were identified as cluster members by the Open Cluster Chemical Abundance & Mapping (OCCAM) survey, which culls member candidates by radial velocity, metallicity and proper motion from the observed APOGEE sample. To obtain data for neutron capture elements in these clusters, we conducted a long-term observing campaign covering three years (2013-2016) using the McDonald Observatory Otto Struve 2.1-m telescope and Sandiford Cass Echelle Spectrograph (R ~ 60,000). We present Galactic neutron capture abundance gradients using 30+ clusters, within 6 kpc of the Sun, covering a range of ages from ~80 Myr to ~10 Gyr .

  7. A survey for low-mass stellar and substellar members of the Hyades open cluster

    Science.gov (United States)

    Melnikov, Stanislav; Eislöffel, Jochen

    2018-03-01

    Context. Unlike young open clusters (with ages 2MASS JHKs photometry Results: We present a photometric and proper motion survey covering 23.4 deg2 in the Hyades cluster core region. Using optical/IR colour-magnitude diagrams, we identify 66 photometric cluster member candidates in the magnitude range 14.m7 < I < 20.m5. The proper motion measurements are based on several all-sky surveys with an epoch difference of 60-70 yr for the bright objects. The proper motions allowed us to discriminate the cluster members from field objects and resulted in 14 proper motion members of the Hyades. We rediscover Hy 6 as a proper motion member and classify it as a substellar object candidate (BD) based on the comparison of the observed colour-magnitude diagram with theoretical model isochrones. Conclusions: With our results, the mass function of the Hyades continues to be shallow below 0.15 M⊙ indicating that the Hyades have probably lost their lowest mass members by means of dynamical evolution. We conclude that the Hyades core represents the "VLM/BD desert" and that most of the substeller objects may have already left the volume of the cluster.

  8. SPECTROSCOPIC CONFIRMATION OF A MASSIVE RED-SEQUENCE-SELECTED GALAXY CLUSTER AT z = 1.34 IN THE SpARCS-SOUTH CLUSTER SURVEY

    International Nuclear Information System (INIS)

    Wilson, Gillian; Demarco, Ricardo; Muzzin, Adam; Yee, H. K. C.; Lacy, Mark; Surace, Jason; Gilbank, David; Blindert, Kris; Hoekstra, Henk; Majumdar, Subhabrata; Gardner, Jonathan P.; Gladders, Michael D.; Lonsdale, Carol

    2009-01-01

    The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a z'-passband imaging survey, consisting of deep (z' ≅ 24 AB) observations made from both hemispheres using the CFHT 3.6 m and CTIO 4 m telescopes. The survey was designed with the primary aim of detecting galaxy clusters at z > 1. In tandem with pre-existing 3.6 μm observations from the Spitzer Space Telescope SWIRE Legacy Survey, SpARCS detects clusters using an infrared adaptation of the two-filter red-sequence cluster technique. The total effective area of the SpARCS cluster survey is 41.9 deg 2 . In this paper, we provide an overview of the 13.6 deg 2 Southern CTIO/MOSAIC II observations. The 28.3 deg 2 Northern CFHT/MegaCam observations are summarized in a companion paper by Muzzin et al. In this paper, we also report spectroscopic confirmation of SpARCS J003550-431224, a very rich galaxy cluster at z = 1.335, discovered in the ELAIS-S1 field. To date, this is the highest spectroscopically confirmed redshift for a galaxy cluster discovered using the red-sequence technique. Based on nine confirmed members, SpARCS J003550-431224 has a preliminary velocity dispersion of 1050 ± 230 km s -1 . With its proven capability for efficient cluster detection, SpARCS is a demonstration that we have entered an era of large, homogeneously selected z > 1 cluster surveys.

  9. THE ARECIBO LEGACY FAST ALFA SURVEY. IX. THE LEO REGION H I CATALOG, GROUP MEMBERSHIP, AND THE H I MASS FUNCTION FOR THE LEO I GROUP

    International Nuclear Information System (INIS)

    Stierwalt, Sabrina; Haynes, Martha P.; Giovanelli, Riccardo; Martin, Ann M.; Kent, Brian R.; Saintonge, Amelie; Karachentsev, Igor D.; Karachentseva, Valentina E.

    2009-01-01

    We present the catalog of H I sources extracted from the ongoing Arecibo Legacy Fast ALFA (ALFALFA) extragalactic H I line survey, found within the sky region bounded by 9 h 36 m h 36 m and +08 0 0 . The H I catalog presented here for this 118 deg 2 region is combined with the ones derived from surrounding regions also covered by the ALFALFA survey to examine the large-scale structure in the complex Leo region. Because of the combination of wide sky coverage and superior sensitivity, spatial and spectral resolution, the ALFALFA H I catalog of the Leo region improves significantly on the numbers of low H I mass sources as compared with those found in previous H I surveys. The H I mass function of the Leo I group presented here is dominated by low-mass objects: 45 of the 65 Leo I members have M H I 8 M-odot, yielding tight constraints on the low-mass slope of the Leo I H I mass function. The best-fit slope is α ≅ -1.41 + 0.2 - 0.1. A direct comparison between the ALFALFA H I line detections and an optical search of the Leo I region proves the advantage of the ALFALFA strategy in finding low-mass, gas-rich dwarfs. These results suggest the existence of a significant population of low surface brightness, gas-rich, yet still very low H I mass galaxies, and may reflect the same type of morphological segregation as is seen in the Local Group. While the low-mass end slope of the Leo I H I mass function is steeper than that determined for luminosity functions of the group, the slope still falls short of the values predicted by simulations of structure formation in the lambda cold dark matter paradigm.

  10. The SUMO project I. A survey of multiple populations in globular clusters

    Science.gov (United States)

    Monelli, M.; Milone, A. P.; Stetson, P. B.; Marino, A. F.; Cassisi, S.; del Pino Molina, A.; Salaris, M.; Aparicio, A.; Asplund, M.; Grundahl, F.; Piotto, G.; Weiss, A.; Carrera, R.; Cebrián, M.; Murabito, S.; Pietrinferni, A.; Sbordone, L.

    2013-05-01

    We present a general overview and the first results of the SUMO project (a SUrvey of Multiple pOpulations in Globular Clusters). The objective of this survey is the study of multiple stellar populations in the largest sample of globular clusters homogeneously analysed to date. To this aim we obtained high signal-to-noise (S/N > 50) photometry for main sequence stars with mass down to ˜0.5 M⊙ in a large sample of clusters using both archival and proprietary U, B, V and I data from ground-based telescopes. In this paper, we focus on the occurrence of multiple stellar populations in 23 clusters. We define a new photometric index, cU, B, I = (U - B) - (B - I), which turns out to be very effective for identifying multiple sequences along the red giant branch (RGB). We found that in the V-cU, B, I diagram all clusters presented in this paper show broadened or multimodal RGBs, with the presence of two or more components. We found a direct connection with the chemical properties of different sequences, which display different abundances of light elements (O, Na, C, N and Al). The cU, B, I index is also a powerful tool for identifying distinct sequences of stars along the horizontal branch and, for the first time in the case of NGC 104 (47 Tuc), along the asymptotic giant branch. Our results demonstrate that (i) the presence of more than two stellar populations is a common feature amongst globular clusters, as already highlighted in previous work; (ii) multiple sequences with different chemical contents can be easily identified by using standard Johnson photometry obtained with ground-based facilities; (iii) in the study of globular cluster multiple stellar populations the cU, B, I index is an alternative to spectroscopy, and has the advantage of larger statistics.

  11. Sejong Open Cluster Survey (SOS). 0. Target Selection and Data Analysis

    Science.gov (United States)

    Sung, Hwankyung; Lim, Beomdu; Bessell, Michael S.; Kim, Jinyoung S.; Hur, Hyeonoh; Chun, Moo-Young; Park, Byeong-Gon

    2013-06-01

    Star clusters are superb astrophysical laboratories containing cospatial and coeval samples of stars with similar chemical composition. We initiate the Sejong Open cluster Survey (SOS) - a project dedicated to providing homogeneous photometry of a large number of open clusters in the SAAO Johnson-Cousins' UBVI system. To achieve our main goal, we pay much attention to the observation of standard stars in order to reproduce the SAAO standard system. Many of our targets are relatively small sparse clusters that escaped previous observations. As clusters are considered building blocks of the Galactic disk, their physical properties such as the initial mass function, the pattern of mass segregation, etc. give valuable information on the formation and evolution of the Galactic disk. The spatial distribution of young open clusters will be used to revise the local spiral arm structure of the Galaxy. In addition, the homogeneous data can also be used to test stellar evolutionary theory, especially concerning rare massive stars. In this paper we present the target selection criteria, the observational strategy for accurate photometry, and the adopted calibrations for data analysis such as color-color relations, zero-age main sequence relations, Sp - M_V relations, Sp - T_{eff} relations, Sp - color relations, and T_{eff} - BC relations. Finally we provide some data analysis such as the determination of the reddening law, the membership selection criteria, and distance determination.

  12. COSMOLOGICAL CONSTRAINTS FROM THE SLOAN DIGITAL SKY SURVEY MaxBCG CLUSTER CATALOG

    International Nuclear Information System (INIS)

    Rozo, Eduardo; Weinberg, David H.; Wechsler, Risa H.; Rykoff, Eli S.; Annis, James T.; Frieman, Joshua A.; Becker, Matthew R.; Evrard, August E.; Hao Jiangang; McKay, Timothy A.; Hansen, Sarah M.; Johnston, David E.; Koester, Benjamin P.; Sheldon, Erin S.

    2010-01-01

    We use the abundance and weak-lensing mass measurements of the Sloan Digital Sky Survey maxBCG cluster catalog to simultaneously constrain cosmology and the richness-mass relation of the clusters. Assuming a flat ΛCDM cosmology, we find σ 8 (Ω m /0.25) 0.41 = 0.832 ± 0.033 after marginalization over all systematics. In common with previous studies, our error budget is dominated by systematic uncertainties, the primary two being the absolute mass scale of the weak-lensing masses of the maxBCG clusters, and uncertainty in the scatter of the richness-mass relation. Our constraints are fully consistent with the WMAP five-year data, and in a joint analysis we find σ 8 = 0.807 ± 0.020 and Ω m = 0.265 ± 0.016, an improvement of nearly a factor of 2 relative to WMAP5 alone. Our results are also in excellent agreement with and comparable in precision to the latest cosmological constraints from X-ray cluster abundances. The remarkable consistency among these results demonstrates that cluster abundance constraints are not only tight but also robust, and highlight the power of optically selected cluster samples to produce precision constraints on cosmological parameters.

  13. Statistical Techniques Applied to Aerial Radiometric Surveys (STAARS): cluster analysis. National Uranium Resource Evaluation

    International Nuclear Information System (INIS)

    Pirkle, F.L.; Stablein, N.K.; Howell, J.A.; Wecksung, G.W.; Duran, B.S.

    1982-11-01

    One objective of the aerial radiometric surveys flown as part of the US Department of Energy's National Uranium Resource Evaluation (NURE) program was to ascertain the regional distribution of near-surface radioelement abundances. Some method for identifying groups of observations with similar radioelement values was therefore required. It is shown in this report that cluster analysis can identify such groups even when no a priori knowledge of the geology of an area exists. A method of convergent k-means cluster analysis coupled with a hierarchical cluster analysis is used to classify 6991 observations (three radiometric variables at each observation location) from the Precambrian rocks of the Copper Mountain, Wyoming, area. Another method, one that combines a principal components analysis with a convergent k-means analysis, is applied to the same data. These two methods are compared with a convergent k-means analysis that utilizes available geologic knowledge. All three methods identify four clusters. Three of the clusters represent background values for the Precambrian rocks of the area, and one represents outliers (anomalously high 214 Bi). A segmentation of the data corresponding to geologic reality as discovered by other methods has been achieved based solely on analysis of aerial radiometric data. The techniques employed are composites of classical clustering methods designed to handle the special problems presented by large data sets. 20 figures, 7 tables

  14. The Next Generation Virgo Cluster Survey (NGVS). XXVI. The Issues of Photometric Age and Metallicity Estimates for Globular Clusters

    Energy Technology Data Exchange (ETDEWEB)

    Powalka, Mathieu; Lançon, Ariane; Duc, Pierre-Alain [Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, F-67000 Strasbourg (France); Puzia, Thomas H.; Muñoz, Roberto P.; Zhang, Hongxin [Institute of Astrophysics, Pontificia Universidad Católica de Chile, 7820436 Macul, Santiago (Chile); Peng, Eric W. [Department of Astronomy, Peking University, Beijing 100871 (China); Liu, Chengze [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Blakeslee, John P.; Côté, Patrick; Ferrarese, Laura; Roediger, Joel; Gwyn, S. D. J. [National Research Council of Canada, Herzberg Astronomy and Astrophysics Program, Victoria, BC V9E 2E7 (Canada); Sánchez-Janssen, Rúben [UK Astronomy Technology Centre, Royal Observatory Edinburgh, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Durrell, Patrick R. [Department of Physics and Astronomy, Youngstown State University, Youngstown, OH (United States); Cuillandre, Jean-Charles [AIM Paris Saclay, CNRS/INSU, CEA/Irfu,Université Paris Diderot, Orme des Merisiers, F-91191 Gif sur Yvette cedex (France); Guhathakurta, Puragra [UCO/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Hudelot, Patrick, E-mail: mathieu.powalka@astro.unistra.fr [Institut d’Astrophysique de Paris, UMR 7095 CNRS and UPMC, 98bis Bd Arago, F-75014 Paris (France); and others

    2017-08-01

    Large samples of globular clusters (GC) with precise multi-wavelength photometry are becoming increasingly available and can be used to constrain the formation history of galaxies. We present the results of an analysis of Milky Way (MW) and Virgo core GCs based on 5 optical-near-infrared colors and 10 synthetic stellar population models. For the MW GCs, the models tend to agree on photometric ages and metallicities, with values similar to those obtained with previous studies. When used with Virgo core GCs, for which photometry is provided by the Next Generation Virgo cluster Survey (NGVS), the same models generically return younger ages. This is a consequence of the systematic differences observed between the locus occupied by Virgo core GCs and models in panchromatic color space. Only extreme fine-tuning of the adjustable parameters available to us can make the majority of the best-fit ages old. Although we cannot exclude that the formation history of the Virgo core may lead to more conspicuous populations of relatively young GCs than in other environments, we emphasize that the intrinsic properties of the Virgo GCs are likely to differ systematically from those assumed in the models. Thus, the large wavelength coverage and photometric quality of modern GC samples, such as those used here, is not by itself sufficient to better constrain the GC formation histories. Models matching the environment-dependent characteristics of GCs in multi-dimensional color space are needed to improve the situation.

  15. THE ACS FORNAX CLUSTER SURVEY. X. COLOR GRADIENTS OF GLOBULAR CLUSTER SYSTEMS IN EARLY-TYPE GALAXIES

    International Nuclear Information System (INIS)

    Liu Chengze; Peng, Eric W.; Jordan, Andres; Ferrarese, Laura; Blakeslee, John P.; Cote, Patrick; Mei, Simona

    2011-01-01

    We use the largest homogeneous sample of globular clusters (GCs), drawn from the ACS Virgo Cluster Survey (ACSVCS) and ACS Fornax Cluster Survey (ACSFCS), to investigate the color gradients of GC systems in 76 early-type galaxies. We find that most GC systems possess an obvious negative gradient in (g-z) color with radius (bluer outward), which is consistent with previous work. For GC systems displaying color bimodality, both metal-rich and metal-poor GC subpopulations present shallower but significant color gradients on average, and the mean color gradients of these two subpopulations are of roughly equal strength. The field of view of ACS mainly restricts us to measuring the inner gradients of the studied GC systems. These gradients, however, can introduce an aperture bias when measuring the mean colors of GC subpopulations from relatively narrow central pointings. Inferred corrections to previous work imply a reduced significance for the relation between the mean color of metal-poor GCs and their host galaxy luminosity. The GC color gradients also show a dependence with host galaxy mass where the gradients are weakest at the ends of the mass spectrum-in massive galaxies and dwarf galaxies-and strongest in galaxies of intermediate mass, around a stellar mass of M * ∼10 10 M sun . We also measure color gradients for field stars in the host galaxies. We find that GC color gradients are systematically steeper than field star color gradients, but the shape of the gradient-mass relation is the same for both. If gradients are caused by rapid dissipational collapse and weakened by merging, these color gradients support a picture where the inner GC systems of most intermediate-mass and massive galaxies formed early and rapidly with the most massive galaxies having experienced greater merging. The lack of strong gradients in the GC systems of dwarfs, which probably have not experienced many recent major mergers, suggests that low-mass halos were inefficient at retaining

  16. Mass and galaxy distributions of four massive galaxy clusters from Dark Energy Survey Science Verification data

    Energy Technology Data Exchange (ETDEWEB)

    Melchior, P.; Suchyta, E.; Huff, E.; Hirsch, M.; Kacprzak, T.; Rykoff, E.; Gruen, D.; Armstrong, R.; Bacon, D.; Bechtol, K.; Bernstein, G. M.; Bridle, S.; Clampitt, J.; Honscheid, K.; Jain, B.; Jouvel, S.; Krause, E.; Lin, H.; MacCrann, N.; Patton, K.; Plazas, A.; Rowe, B.; Vikram, V.; Wilcox, H.; Young, J.; Zuntz, J.; Abbott, T.; Abdalla, F. B.; Allam, S. S.; Banerji, M.; Bernstein, J. P.; Bernstein, R. A.; Bertin, E.; Buckley-Geer, E.; Burke, D. L.; Castander, F. J.; da Costa, L. N.; Cunha, C. E.; Depoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Estrada, J.; Evrard, A. E.; Neto, A. F.; Fernandez, E.; Finley, D. A.; Flaugher, B.; Frieman, J. A.; Gaztanaga, E.; Gerdes, D.; Gruendl, R. A.; Gutierrez, G. R.; Jarvis, M.; Karliner, I.; Kent, S.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Maia, M. A. G.; Makler, M.; Marriner, J.; Marshall, J. L.; Merritt, K. W.; Miller, C. J.; Miquel, R.; Mohr, J.; Neilsen, E.; Nichol, R. C.; Nord, B. D.; Reil, K.; Roe, N. A.; Roodman, A.; Sako, M.; Sanchez, E.; Santiago, B. X.; Schindler, R.; Schubnell, M.; Sevilla-Noarbe, I.; Sheldon, E.; Smith, C.; Soares-Santos, M.; Swanson, M. E. C.; Sypniewski, A. J.; Tarle, G.; Thaler, J.; Thomas, D.; Tucker, D. L.; Walker, A.; Wechsler, R.; Weller, J.; Wester, W.

    2015-03-31

    We measure the weak-lensing masses and galaxy distributions of four massive galaxy clusters observed during the Science Verification phase of the Dark Energy Survey. This pathfinder study is meant to 1) validate the DECam imager for the task of measuring weak-lensing shapes, and 2) utilize DECam's large field of view to map out the clusters and their environments over 90 arcmin. We conduct a series of rigorous tests on astrometry, photometry, image quality, PSF modeling, and shear measurement accuracy to single out flaws in the data and also to identify the optimal data processing steps and parameters. We find Science Verification data from DECam to be suitable for the lensing analysis described in this paper. The PSF is generally well-behaved, but the modeling is rendered difficult by a flux-dependent PSF width and ellipticity. We employ photometric redshifts to distinguish between foreground and background galaxies, and a red-sequence cluster finder to provide cluster richness estimates and cluster-galaxy distributions. By fitting NFW profiles to the clusters in this study, we determine weak-lensing masses that are in agreement with previous work. For Abell 3261, we provide the first estimates of redshift, weak-lensing mass, and richness. In addition, the cluster-galaxy distributions indicate the presence of filamentary structures attached to 1E 0657-56 and RXC J2248.7-4431, stretching out as far as 1 degree (approximately 20 Mpc), showcasing the potential of DECam and DES for detailed studies of degree-scale features on the sky.

  17. THE EVOLUTION OF DUSTY STAR FORMATION IN GALAXY CLUSTERS TO z = 1: SPITZER INFRARED OBSERVATIONS OF THE FIRST RED-SEQUENCE CLUSTER SURVEY

    International Nuclear Information System (INIS)

    Webb, T. M. A.; O'Donnell, D.; Coppin, Kristen; Faloon, Ashley; Geach, James E.; Noble, Allison; Yee, H. K. C.; Gilbank, David; Ellingson, Erica; Gladders, Mike; Muzzin, Adam; Wilson, Gillian; Yan, Renbin

    2013-01-01

    We present the results of an infrared (IR) study of high-redshift galaxy clusters with the MIPS camera on board the Spitzer Space Telescope. We have assembled a sample of 42 clusters from the Red-Sequence Cluster Survey-1 over the redshift range 0.3 14-15 M ☉ . We statistically measure the number of IR-luminous galaxies in clusters above a fixed inferred IR luminosity of 2 × 10 11 M ☉ , assuming a star forming galaxy template, per unit cluster mass and find it increases to higher redshift. Fitting a simple power-law we measure evolution of (1 + z) 5.1±1.9 over the range 0.3 cluster ). The evolution is similar, with ΣSFR/M cluster ∼ (1 + z) 5.4±1.9 . We show that this can be accounted for by the evolution of the IR-bright field population over the same redshift range; that is, the evolution can be attributed entirely to the change in the in-falling field galaxy population. We show that the ΣSFR/M cluster (binned over all redshift) decreases with increasing cluster mass with a slope (ΣSFR/M cluster ∼M cluster -1.5±0.4 ) consistent with the dependence of the stellar-to-total mass per unit cluster mass seen locally. The inferred star formation seen here could produce ∼5%-10% of the total stellar mass in massive clusters at z = 0, but we cannot constrain the descendant population, nor how rapidly the star-formation must shut-down once the galaxies have entered the cluster environment. Finally, we show a clear decrease in the number of IR-bright galaxies per unit optical galaxy in the cluster cores, confirming star formation continues to avoid the highest density regions of the universe at z ∼ 0.75 (the average redshift of the high-redshift clusters). While several previous studies appear to show enhanced star formation in high-redshift clusters relative to the field we note that these papers have not accounted for the overall increase in galaxy or dark matter density at the location of clusters. Once this is done, clusters at z ∼ 0.75 have the same

  18. Female cluster headache in the United States of America: what are the gender differences? Results from the United States Cluster Headache Survey.

    Science.gov (United States)

    Rozen, Todd D; Fishman, Royce S

    2012-06-15

    To present results from the United States Cluster Headache Survey regarding gender differences in cluster headache demographics, clinical characteristics, diagnostic delay, triggers, treatment response and personal burden. Very few studies have looked at the gender differences in cluster headache presentation. The United States Cluster Headache Survey is the largest study of cluster headache sufferers ever completed in the United States and it is also the largest study of female cluster headache patients ever presented. The total survey consisted of 187 multiple choice questions which dealt with various issues related to cluster headache including: demographics, clinical characteristics, concomitant medical conditions, family history, triggers, smoking history, diagnosis, treatment response and personal burden. A group of questions were specifically targeted to female cluster headache patients. The survey was placed on a website from October to December 2008. For all survey responders the diagnosis of cluster headache needed to be made by a neurologist but there was no validation of the headache diagnosis by the authors. 1134 individuals completed the survey (816 male, 318 female). Key Points that define the differences between female and male cluster headache include: a. Age of onset: women develop cluster headache at an earlier age than men and are more likely to develop a second peak of cluster headache onset after 50 years of age. b. Family history: woman cluster headache sufferers are more likely to have a family history of both cluster headache and migraine and have an increased familial risk of Parkinson's disease. c. Comorbid conditions: female cluster headaches sufferers are significantly more likely to experience depression and have asthma than males. d. Aura issues: aura with cluster headache is equally common in both sexes, but aura duration is shorter in women. Women are much more likely to experience sensory, language and brainstem auras. e. Pain

  19. clusters

    Indian Academy of Sciences (India)

    2017-09-27

    Sep 27, 2017 ... Author for correspondence (zh4403701@126.com). MS received 15 ... lic clusters using density functional theory (DFT)-GGA of the DMOL3 package. ... In the process of geometric optimization, con- vergence thresholds ..... and Postgraduate Research & Practice Innovation Program of. Jiangsu Province ...

  20. clusters

    Indian Academy of Sciences (India)

    environmental as well as technical problems during fuel gas utilization. ... adsorption on some alloys of Pd, namely PdAu, PdAg ... ried out on small neutral and charged Au24,26,27, Cu,28 ... study of Zanti et al.29 on Pdn (n = 1–9) clusters.

  1. YOUNG STELLAR CLUSTERS CONTAINING MASSIVE YOUNG STELLAR OBJECTS IN THE VVV SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Borissova, J.; Alegría, S. Ramírez; Kurtev, R.; Medina, N.; Navarro, C.; Kuhn, M.; Gromadzki, M.; Retamales, G.; Fernandez, M. A.; Agurto-Gangas, C.; Amigo, P. [Instituto de Física y Astronomía, Universidad de Valparaíso, Av. Gran Bretaña 1111, Playa Ancha, Casilla 5030 (Chile); Alonso, J.; Decany, I. [Millennium Institute of Astrophysics (MAS), Santiago (Chile); Lucas, P. W.; Pena, C. Contreras; Thompson, M. A. [Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom); Chené, A.-N. [Gemini Observatory, Northern Operations Center, 670 N. A’ohoku Place, Hilo, HI 96720 (United States); Minniti, D. [Departamento de Ciencias Físicas, Universidad Andres Bello, Republica 220, Santiago (Chile); Catelan, M. [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile); Morales, E. F. E., E-mail: jura.borissova@uv.cl [Max-Planck-Institute for Astronomy (Germany)

    2016-09-01

    The purpose of this research is to study the connections of the global properties of eight young stellar clusters projected in the Vista Variables in the Via Lactea (VVV) ESO Large Public Survey disk area and their young stellar object (YSO) populations. The analysis is based on the combination of spectroscopic parallax-based reddening and distance determinations with main-sequence and pre-main-sequence ishochrone fitting to determine the basic parameters (reddening, age, distance) of the sample clusters. The lower mass limit estimations show that all clusters are low or intermediate mass (between 110 and 1800  M {sub ⊙}), the slope Γ of the obtained present-day mass functions of the clusters is close to the Kroupa initial mass function. The YSOs in the cluster’s surrounding fields are classified using low resolution spectra, spectral energy distribution fits with theoretical predictions, and variability, taking advantage of multi-epoch VVV observations. All spectroscopically confirmed YSOs (except one) are found to be massive (more than 8 M {sub ⊙}). Using VVV and GLIMPSE color–color cuts we have selected a large number of new YSO candidates, which are checked for variability and 57% are found to show at least low-amplitude variations. In few cases it was possible to distinguish between YSO and AGB classifications on the basis of light curves.

  2. Interpreting results of cluster surveys in emergency settings: is the LQAS test the best option?

    Science.gov (United States)

    Bilukha, Oleg O; Blanton, Curtis

    2008-12-09

    Cluster surveys are commonly used in humanitarian emergencies to measure health and nutrition indicators. Deitchler et al. have proposed to use Lot Quality Assurance Sampling (LQAS) hypothesis testing in cluster surveys to classify the prevalence of global acute malnutrition as exceeding or not exceeding the pre-established thresholds. Field practitioners and decision-makers must clearly understand the meaning and implications of using this test in interpreting survey results to make programmatic decisions. We demonstrate that the LQAS test--as proposed by Deitchler et al.--is prone to producing false-positive results and thus is likely to suggest interventions in situations where interventions may not be needed. As an alternative, to provide more useful information for decision-making, we suggest reporting the probability of an indicator's exceeding the threshold as a direct measure of "risk". Such probability can be easily determined in field settings by using a simple spreadsheet calculator. The "risk" of exceeding the threshold can then be considered in the context of other aggravating and protective factors to make informed programmatic decisions.

  3. Interpreting results of cluster surveys in emergency settings: is the LQAS test the best option?

    Directory of Open Access Journals (Sweden)

    Blanton Curtis

    2008-12-01

    Full Text Available Abstract Cluster surveys are commonly used in humanitarian emergencies to measure health and nutrition indicators. Deitchler et al. have proposed to use Lot Quality Assurance Sampling (LQAS hypothesis testing in cluster surveys to classify the prevalence of global acute malnutrition as exceeding or not exceeding the pre-established thresholds. Field practitioners and decision-makers must clearly understand the meaning and implications of using this test in interpreting survey results to make programmatic decisions. We demonstrate that the LQAS test–as proposed by Deitchler et al. – is prone to producing false-positive results and thus is likely to suggest interventions in situations where interventions may not be needed. As an alternative, to provide more useful information for decision-making, we suggest reporting the probability of an indicator's exceeding the threshold as a direct measure of "risk". Such probability can be easily determined in field settings by using a simple spreadsheet calculator. The "risk" of exceeding the threshold can then be considered in the context of other aggravating and protective factors to make informed programmatic decisions.

  4. Don't spin the pen: two alternative methods for second-stage sampling in urban cluster surveys

    Directory of Open Access Journals (Sweden)

    Rose Angela MC

    2007-06-01

    Full Text Available Abstract In two-stage cluster surveys, the traditional method used in second-stage sampling (in which the first household in a cluster is selected is time-consuming and may result in biased estimates of the indicator of interest. Firstly, a random direction from the center of the cluster is selected, usually by spinning a pen. The houses along that direction are then counted out to the boundary of the cluster, and one is then selected at random to be the first household surveyed. This process favors households towards the center of the cluster, but it could easily be improved. During a recent meningitis vaccination coverage survey in Maradi, Niger, we compared this method of first household selection to two alternatives in urban zones: 1 using a superimposed grid on the map of the cluster area and randomly selecting an intersection; and 2 drawing the perimeter of the cluster area using a Global Positioning System (GPS and randomly selecting one point within the perimeter. Although we only compared a limited number of clusters using each method, we found the sampling grid method to be the fastest and easiest for field survey teams, although it does require a map of the area. Selecting a random GPS point was also found to be a good method, once adequate training can be provided. Spinning the pen and counting households to the boundary was the most complicated and time-consuming. The two methods tested here represent simpler, quicker and potentially more robust alternatives to spinning the pen for cluster surveys in urban areas. However, in rural areas, these alternatives would favor initial household selection from lower density (or even potentially empty areas. Bearing in mind these limitations, as well as available resources and feasibility, investigators should choose the most appropriate method for their particular survey context.

  5. The Open Cluster Chemical Abundances and Mapping (OCCAM) Survey: Detailed Age and Abundance Gradients using DR12

    Science.gov (United States)

    Frinchaboy, Peter M.; Thompson, Benjamin A.; O'Connell, Julia; Meyer, Brianne; Donor, John; Majewski, Steven R.; Holtzman, Jon A.; Zasowski, Gail; Beers, Timothy C.; Beaton, Rachael; Cunha, Katia M. L.; Hearty, Fred; Nidever, David L.; Schiavon, Ricardo P.; Smith, Verne V.; Hayden, Michael R.

    2015-01-01

    We present detailed abundance results for Galactic open clusters as part of the Open Cluster Chemical Abundances and Mapping (OCCAM) Survey, which is based primarily on data from the Sloan Digital Sky Survey/ Apache Point Observatory Galactic Evolution Experiment. Using 100 open clusters from the uniformly observed complete SDSS-III/APOGEE-1 DR12 dataset, we present age and multi-element abundance gradients for the disk of the Milky Way.This work is supported by an NSF AAG grant AST-1311835.

  6. The sluggs survey: HST/ACS mosaic imaging of the NGC 3115 globular cluster system

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, Zachary G.; Romanowsky, Aaron J.; Brodie, Jean P.; Arnold, Jacob A. [University of California Observatories, Santa Cruz, CA 95064 (United States); Strader, Jay [Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan, MI 48824 (United States); Lin, Dacheng; Irwin, Jimmy A.; Wong, Ka-Wah [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487 (United States); Sivakoff, Gregory R., E-mail: zgjennin@ucsc.edu [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1 (Canada)

    2014-08-01

    We present Hubble Space Telescope/Advanced Camera for Surveys (HST/ACS) g and z photometry and half-light radii R {sub h} measurements of 360 globular cluster (GC) candidates around the nearby S0 galaxy NGC 3115. We also include Subaru/Suprime-Cam g, r, and i photometry of 421 additional candidates. The well-established color bimodality of the GC system is obvious in the HST/ACS photometry. We find evidence for a 'blue tilt' in the blue GC subpopulation, wherein the GCs in the blue subpopulation get redder as luminosity increases, indicative of a mass-metallicity relationship. We find a color gradient in both the red and blue subpopulations, with each group of clusters becoming bluer at larger distances from NGC 3115. The gradient is of similar strength in both subpopulations, but is monotonic and more significant for the blue clusters. On average, the blue clusters have ∼10% larger R {sub h} than the red clusters. This average difference is less than is typically observed for early-type galaxies but does match that measured in the literature for the Sombrero Galaxy (M104), suggesting that morphology and inclination may affect the measured size difference between the red and blue clusters. However, the scatter on the R {sub h} measurements is large. We also identify 31 clusters more extended than typical GCs, which we term ultra-compact dwarf (UCD) candidates. Many of these objects are actually considerably fainter than typical UCDs. While it is likely that a significant number will be background contaminants, six of these UCD candidates are spectroscopically confirmed as NGC 3115 members. To explore the prevalence of low-mass X-ray binaries in the GC system, we match our ACS and Suprime-Cam detections to corresponding Chandra X-ray sources. We identify 45 X-ray-GC matches: 16 among the blue subpopulation and 29 among the red subpopulation. These X-ray/GC coincidence fractions are larger than is typical for most GC systems, probably due to the increased

  7. CLUSTERING OF SLOAN DIGITAL SKY SURVEY III PHOTOMETRIC LUMINOUS GALAXIES: THE MEASUREMENT, SYSTEMATICS, AND COSMOLOGICAL IMPLICATIONS

    International Nuclear Information System (INIS)

    Ho, Shirley; White, Martin; Schlegel, David J.; Seljak, Uros; Reid, Beth; Cuesta, Antonio; Padmanabhan, Nikhil; Seo, Hee-Jong; De Putter, Roland; Ross, Ashley J.; Percival, Will J.; Saito, Shun; Schlafly, Eddie; Hernández-Monteagudo, Carlos; Sánchez, Ariel G.; Blanton, Michael; Skibba, Ramin; Schneider, Don; Mena, Olga; Viel, Matteo

    2012-01-01

    The Sloan Digital Sky Survey (SDSS) surveyed 14,555 deg 2 , and delivered over a trillion pixels of imaging data. We present a study of galaxy clustering using 900,000 luminous galaxies with photometric redshifts, spanning between z = 0.45 and z = 0.65, constructed from the SDSS using methods described in Ross et al. This data set spans 11,000 deg 2 and probes a volume of 3 h –3 Gpc 3 , making it the largest volume ever used for galaxy clustering measurements. We describe in detail the construction of the survey window function and various systematics affecting our measurement. With such a large volume, high-precision cosmological constraints can be obtained given careful control and understanding of the observational systematics. We present a novel treatment of the observational systematics and its applications to the clustering signals from the data set. In this paper, we measure the angular clustering using an optimal quadratic estimator at four redshift slices with an accuracy of ∼15%, with a bin size of δ l = 10 on scales of the baryon acoustic oscillations (BAOs; at l ∼ 40-400). We also apply corrections to the power spectra due to systematics and derive cosmological constraints using the full shape of the power spectra. For a flat ΛCDM model, when combined with cosmic microwave background Wilkinson Microwave Anisotropy Probe 7 (WMAP7) and H 0 constraints from using 600 Cepheids observed by Wide Field Camera 3 (WFC3; HST), we find Ω Λ = 0.73 ± 0.019 and H 0 to be 70.5 ± 1.6 s –1 Mpc –1 km. For an open ΛCDM model, when combined with WMAP7 + HST, we find Ω K = 0.0035 ± 0.0054, improved over WMAP7+HST alone by 40%. For a wCDM model, when combined with WMAP7+HST+SN, we find w = –1.071 ± 0.078, and H 0 to be 71.3 ± 1.7 s –1 Mpc –1 km, which is competitive with the latest large-scale structure constraints from large spectroscopic surveys such as the SDSS Data Release 7 (DR7) and WiggleZ. We also find that systematic-corrected power

  8. CLUSTERING OF SLOAN DIGITAL SKY SURVEY III PHOTOMETRIC LUMINOUS GALAXIES: THE MEASUREMENT, SYSTEMATICS, AND COSMOLOGICAL IMPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Shirley; White, Martin; Schlegel, David J.; Seljak, Uros; Reid, Beth [Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, MS 50R-5045, Berkeley, CA 94720 (United States); Cuesta, Antonio; Padmanabhan, Nikhil [Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06511 (United States); Seo, Hee-Jong [Berkeley Center for Cosmological Physics, LBL and Department of Physics, University of California, Berkeley, CA 94720 (United States); De Putter, Roland [ICC, University of Barcelona (IEEC-UB), Marti i Franques 1, E-08028 Barcelona (Spain); Ross, Ashley J.; Percival, Will J. [Institute of Cosmology and Gravitation, Dennis Sciama Building, University of Portsmouth, Portsmouth PO1 3FX (United Kingdom); Saito, Shun [Department of Astronomy, University of California Berkeley, CA (United States); Schlafly, Eddie [Department of Astronomy, Harvard University, 60 Garden St. MS 20, Cambridge, MA 02138 (United States); Hernandez-Monteagudo, Carlos [Centro de Estudios de Fisica del Cosmos de Aragon (CEFCA), Plaza de San Juan 1, planta 2, E-44001 Teruel (Spain); Sanchez, Ariel G. [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); Blanton, Michael [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Skibba, Ramin [Steward Observatory, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Schneider, Don [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Mena, Olga [Instituto de Fisica Corpuscular, Universidad de Valencia-CSIC (Spain); Viel, Matteo, E-mail: cwho@lbl.gov [INAF-Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, I-34131 Trieste (Italy); and others

    2012-12-10

    The Sloan Digital Sky Survey (SDSS) surveyed 14,555 deg{sup 2}, and delivered over a trillion pixels of imaging data. We present a study of galaxy clustering using 900,000 luminous galaxies with photometric redshifts, spanning between z = 0.45 and z = 0.65, constructed from the SDSS using methods described in Ross et al. This data set spans 11,000 deg{sup 2} and probes a volume of 3 h {sup -3} Gpc{sup 3}, making it the largest volume ever used for galaxy clustering measurements. We describe in detail the construction of the survey window function and various systematics affecting our measurement. With such a large volume, high-precision cosmological constraints can be obtained given careful control and understanding of the observational systematics. We present a novel treatment of the observational systematics and its applications to the clustering signals from the data set. In this paper, we measure the angular clustering using an optimal quadratic estimator at four redshift slices with an accuracy of {approx}15%, with a bin size of {delta}{sub l} = 10 on scales of the baryon acoustic oscillations (BAOs; at l {approx} 40-400). We also apply corrections to the power spectra due to systematics and derive cosmological constraints using the full shape of the power spectra. For a flat {Lambda}CDM model, when combined with cosmic microwave background Wilkinson Microwave Anisotropy Probe 7 (WMAP7) and H{sub 0} constraints from using 600 Cepheids observed by Wide Field Camera 3 (WFC3; HST), we find {Omega}{sub {Lambda}} = 0.73 {+-} 0.019 and H{sub 0} to be 70.5 {+-} 1.6 s{sup -1} Mpc{sup -1} km. For an open {Lambda}CDM model, when combined with WMAP7 + HST, we find {Omega}{sub K} = 0.0035 {+-} 0.0054, improved over WMAP7+HST alone by 40%. For a wCDM model, when combined with WMAP7+HST+SN, we find w = -1.071 {+-} 0.078, and H{sub 0} to be 71.3 {+-} 1.7 s{sup -1} Mpc{sup -1} km, which is competitive with the latest large-scale structure constraints from large spectroscopic

  9. The HST/ACS Coma Cluster Survey - VII. Structure and assembly of massive galaxies in the centre of the Coma cluster

    NARCIS (Netherlands)

    Weinzirl, Tim; Jogee, Shardha; Neistein, Eyal; Khochfar, Sadegh; Kormendy, John; Marinova, Irina; Hoyos, Carlos; Balcells, Marc; den Brok, Mark; Hammer, Derek; Peletier, Reynier F.; Kleijn, Gijs Verdoes; Carter, David; Goudfrooij, Paul; Lucey, John R.; Mobasher, Bahram; Trentham, Neil; Erwin, Peter; Puzia, Thomas

    2014-01-01

    We constrain the assembly history of galaxies in the projected central 0.5 Mpc of the Coma cluster by performing structural decomposition on 69 massive (M⋆ ≥ 109 M⊙) galaxies using high-resolution F814W images from the Hubble Space Telescope (HST) Treasury Survey of Coma. Each galaxy is modelled

  10. The KMOS Cluster Survey (KCS). III. Fundamental Plane of Cluster Galaxies at z ≃ 1.80 in JKCS 041

    Science.gov (United States)

    Prichard, Laura J.; Davies, Roger L.; Beifiori, Alessandra; Chan, Jeffrey C. C.; Cappellari, Michele; Houghton, Ryan C. W.; Mendel, J. Trevor; Bender, Ralf; Galametz, Audrey; Saglia, Roberto P.; Stott, John P.; Wilman, David J.; Lewis, Ian J.; Sharples, Ray; Wegner, Michael

    2017-12-01

    We present data for 16 galaxies in the overdensity JKCS 041 at z≃ 1.80 as part of the K-band Multi-Object Spectrograph (KMOS) Cluster Survey (KCS). With 20 hr integrations, we have obtained deep absorption-line spectra from which we derived velocity dispersions for seven quiescent galaxies. We combined photometric parameters derived from Hubble Space Telescope images with the dispersions to construct a fundamental plane (FP) for quiescent galaxies in JKCS 041. From the zero-point evolution of the FP, we derived a formation redshift for the galaxies of {z}{form}=3.0+/- 0.3, corresponding to a mean age of 1.4 ± 0.2 Gyr. We tested the effect of structural and velocity dispersion evolution on our FP zero-point and found a negligible contribution when using dynamical mass-normalized parameters (˜ 3 % ) but a significant contribution from stellar-mass-normalized parameters (˜ 42 % ). From the relative velocities of the galaxies, we probed the 3D structure of these 16 confirmed members of JKCS 041 and found that a group of galaxies in the southwest of the overdensity had systematically higher velocities. We derived ages for the galaxies in the different groups from the FP. We found that the east-extending group had typically older galaxies ({2.1}-0.2+0.3 Gyr) than those in the southwest group (0.3 ± 0.2 Gyr). Although based on small numbers, the overdensity dynamics, morphology, and age results could indicate that JKCS 041 is in formation and may comprise two merging groups of galaxies. This result could link large-scale structure to ages of galaxies for the first time at this redshift. Based on observations obtained at the Very Large Telescope (VLT) of the European Southern Observatory (ESO), Paranal, Chile (ESO program IDs: 095.A-0137(A) and 096.A-0189(A)).

  11. Cluster Mass Calibration at High Redshift: HST Weak Lensing Analysis of 13 Distant Galaxy Clusters from the South Pole Telescope Sunyaev-Zel’dovich Survey

    Energy Technology Data Exchange (ETDEWEB)

    Schrabback, T.; Applegate, D.; Dietrich, J. P.; Hoekstra, H.; Bocquet, S.; Gonzalez, A. H.; der Linden, A. von; McDonald, M.; Morrison, C. B.; Raihan, S. F.; Allen, S. W.; Bayliss, M.; Benson, B. A.; Bleem, L. E.; Chiu, I.; Desai, S.; Foley, R. J.; de Haan, T.; High, F. W.; Hilbert, S.; Mantz, A. B.; Massey, R.; Mohr, J.; Reichardt, C. L.; Saro, A.; Simon, P.; Stern, C.; Stubbs, C. W.; Zenteno, A.

    2017-10-14

    We present an HST/Advanced Camera for Surveys (ACS) weak gravitational lensing analysis of 13 massive high-redshift (z(median) = 0.88) galaxy clusters discovered in the South Pole Telescope (SPT) Sunyaev-Zel'dovich Survey. This study is part of a larger campaign that aims to robustly calibrate mass-observable scaling relations over a wide range in redshift to enable improved cosmological constraints from the SPT cluster sample. We introduce new strategies to ensure that systematics in the lensing analysis do not degrade constraints on cluster scaling relations significantly. First, we efficiently remove cluster members from the source sample by selecting very blue galaxies in V - I colour. Our estimate of the source redshift distribution is based on Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) data, where we carefully mimic the source selection criteria of the cluster fields. We apply a statistical correction for systematic photometric redshift errors as derived from Hubble Ultra Deep Field data and verified through spatial cross-correlations. We account for the impact of lensing magnification on the source redshift distribution, finding that this is particularly relevant for shallower surveys. Finally, we account for biases in the mass modelling caused by miscentring and uncertainties in the concentration-mass relation using simulations. In combination with temperature estimates from Chandra we constrain the normalization of the mass-temperature scaling relation ln (E(z) M-500c/10(14)M(circle dot)) = A + 1.5ln (kT/7.2 keV) to A = 1.81(-0.14)(+0.24)(stat.)+/- 0.09(sys.), consistent with self-similar redshift evolution when compared to lower redshift samples. Additionally, the lensing data constrain the average concentration of the clusters to c(200c) = 5.6(-1.8)(+3.7).

  12. Cluster mass calibration at high redshift: HST weak lensing analysis of 13 distant galaxy clusters from the South Pole Telescope Sunyaev-Zel'dovich Survey

    Science.gov (United States)

    Schrabback, T.; Applegate, D.; Dietrich, J. P.; Hoekstra, H.; Bocquet, S.; Gonzalez, A. H.; von der Linden, A.; McDonald, M.; Morrison, C. B.; Raihan, S. F.; Allen, S. W.; Bayliss, M.; Benson, B. A.; Bleem, L. E.; Chiu, I.; Desai, S.; Foley, R. J.; de Haan, T.; High, F. W.; Hilbert, S.; Mantz, A. B.; Massey, R.; Mohr, J.; Reichardt, C. L.; Saro, A.; Simon, P.; Stern, C.; Stubbs, C. W.; Zenteno, A.

    2018-02-01

    We present an HST/Advanced Camera for Surveys (ACS) weak gravitational lensing analysis of 13 massive high-redshift (zmedian = 0.88) galaxy clusters discovered in the South Pole Telescope (SPT) Sunyaev-Zel'dovich Survey. This study is part of a larger campaign that aims to robustly calibrate mass-observable scaling relations over a wide range in redshift to enable improved cosmological constraints from the SPT cluster sample. We introduce new strategies to ensure that systematics in the lensing analysis do not degrade constraints on cluster scaling relations significantly. First, we efficiently remove cluster members from the source sample by selecting very blue galaxies in V - I colour. Our estimate of the source redshift distribution is based on Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) data, where we carefully mimic the source selection criteria of the cluster fields. We apply a statistical correction for systematic photometric redshift errors as derived from Hubble Ultra Deep Field data and verified through spatial cross-correlations. We account for the impact of lensing magnification on the source redshift distribution, finding that this is particularly relevant for shallower surveys. Finally, we account for biases in the mass modelling caused by miscentring and uncertainties in the concentration-mass relation using simulations. In combination with temperature estimates from Chandra we constrain the normalization of the mass-temperature scaling relation ln (E(z)M500c/1014 M⊙) = A + 1.5ln (kT/7.2 keV) to A=1.81^{+0.24}_{-0.14}(stat.) {± } 0.09(sys.), consistent with self-similar redshift evolution when compared to lower redshift samples. Additionally, the lensing data constrain the average concentration of the clusters to c_200c=5.6^{+3.7}_{-1.8}.

  13. A survey of energy conservation mechanisms for dynamic cluster based wireless sensor networks

    International Nuclear Information System (INIS)

    Enam, R.N.; Tahir, M.; Ahmed, S.; Qureshi, R.

    2018-01-01

    WSN (Wireless Sensor Network) is an emerging technology that has unlimited potential for numerous application areas including military, crisis management, environmental, transportation, medical, home/ city automations and smart spaces. But energy constrained nature of WSNs necessitates that their architecture and communicating protocols to be designed in an energy aware manner. Sensor data collection through clustering mechanisms has become a common strategy in WSN. This paper presents a survey report on the major perspectives with which energy conservation mechanisms has been proposed in dynamic cluster based WSNs so far. All the solutions discussed in this paper focus on the cluster based protocols only.We have covered a vast scale of existing energy efficient protocols and have categorized them in six categories. In the beginning of this paper the fundamentals of the energy constraint issues of WSNs have been discussed and an overview of the causes of energy consumptions at all layers of WSN has been given. Later in this paper several previously proposed energy efficient protocols of WSNs are presented. (author)

  14. Dietary habits and physical activity patterns among Slovenian elderly: cross-sectional survey with cluster analysis

    Directory of Open Access Journals (Sweden)

    Joca Zurc

    2015-03-01

    Full Text Available Introduction: Physical activity and a healthy diet are significant predictors of healthy ageing—they help the elderly maintain their physical and mental health, and prevent chronic diseases. Methods: The data for the empirical quantitative survey were collected on the sample of 218 elderly community-dwelling participants (aged 65 years or more, using a structured questionnaire for self-reporting. Data analyses were proceed with the bivariate statistics, and multivariate hierarchical cluster analysis. Results: Most respondents reported good dietary habits (83.1% and a satisfactory physical activity level (60.5%. On average, the elderly eat 3-4 meals per day (59.8% and engage in physical activity at least three times a week (58.6%, with interventions lasting 15 minutes or more (84.4 % and non-organized activity prevailing (96.2%. Ward’s method yielded three clusters with homogenous dietary and physical activity patterns: ‘Health Conscious’ (30.8%, ‘At Risk’ (42.7% and ‘Special Requirements’ (26.5%. Significant differences were identified between clusters and educational level (p = 0.001. Discussion and conclusions: In the future, special attention should be placed on the elderly group with a lower educational level and special dietary and physical activity requirements. Additional studies on representative samples are required for a comprehensive investigation into the lifestyle behaviours of elderly individuals.

  15. The SLUGGS survey: globular cluster stellar population trends from weak absorption lines in stacked spectra

    Science.gov (United States)

    Usher, Christopher; Forbes, Duncan A.; Brodie, Jean P.; Romanowsky, Aaron J.; Strader, Jay; Conroy, Charlie; Foster, Caroline; Pastorello, Nicola; Pota, Vincenzo; Arnold, Jacob A.

    2015-01-01

    As part of the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey, we stack 1137 Keck DEIMOS (Deep Imaging Multi-Object Spectrograph) spectra of globular clusters from 10 galaxies to study their stellar populations in detail. The stacked spectra have median signal-to-noise ratios of ˜90 Å-1. Besides the calcium triplet, we study weaker sodium, magnesium, titanium and iron lines as well as the Hα and higher order Paschen hydrogen lines. In general, the stacked spectra are consistent with old ages and a Milky Way-like initial mass function. However, we see different metal line index strengths at fixed colour and magnitude, and differences in the calcium triplet-colour relation from galaxy to galaxy. We interpret this as strong evidence for variations in the globular cluster colour-metallicity relation between galaxies. Two possible explanations for the colour-metallicity relation variations are that the average ages of globular clusters vary from galaxy to galaxy or that the average abundances of light elements (i.e. He, C, N and O) differ between galaxies. Stacking spectra by magnitude, we see that the colours become redder and metal line indices stronger with brighter magnitudes. These trends are consistent with the previously reported `blue tilts' being mass-metallicity relations.

  16. THE CLUSTERING CHARACTERISTICS OF H I-SELECTED GALAXIES FROM THE 40% ALFALFA SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Ann M. [NASA Postdoctoral Program, NASA Langley Research Center, Hampton, VA 23618 (United States); Giovanelli, Riccardo; Haynes, Martha P. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Guzzo, Luigi, E-mail: ann.m.martin@nasa.gov, E-mail: riccardo@astro.cornell.edu, E-mail: haynes@astro.cornell.edu, E-mail: luigi.guzzo@brera.inaf.it [INAF Osservatorio Astronomico di Brera, Milan (Italy)

    2012-05-01

    The 40% Arecibo Legacy Fast ALFA survey catalog ({alpha}.40) of {approx}10,150 H I-selected galaxies is used to analyze the clustering properties of gas-rich galaxies. By employing the Landy-Szalay estimator and a full covariance analysis for the two-point galaxy-galaxy correlation function, we obtain the real-space correlation function and model it as a power law, {xi}(r) = (r/r{sub 0}){sup -{gamma}}, on scales <10 h{sup -1} Mpc. As the largest sample of blindly H I-selected galaxies to date, {alpha}.40 provides detailed understanding of the clustering of this population. We find {gamma} = 1.51 {+-} 0.09 and r{sub 0} = 3.3 + 0.3, -0.2 h{sup -1} Mpc, reinforcing the understanding that gas-rich galaxies represent the most weakly clustered galaxy population known; we also observe a departure from a pure power-law shape at intermediate scales, as predicted in {Lambda}CDM halo occupation distribution models. Furthermore, we measure the bias parameter for the {alpha}.40 galaxy sample and find that H I galaxies are severely antibiased on small scales, but only weakly antibiased on large scales. The robust measurement of the correlation function for gas-rich galaxies obtained via the {alpha}.40 sample constrains models of the distribution of H I in simulated galaxies, and will be employed to better understand the role of gas in environmentally dependent galaxy evolution.

  17. A Survey of Energy Conservation Mechanisms for Dynamic Cluster Based Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Rabia Noor Enam

    2018-04-01

    Full Text Available WSN (Wireless Sensor Network is an emerging technology that has unlimited potential for numerous application areas including military, crisis management, environmental, transportation, medical, home/ city automations and smart spaces. But energy constrained nature of WSNs necessitates that their architecture and communicating protocols to be designed in an energy aware manner. Sensor data collection through clustering mechanisms has become a common strategy in WSN. This paper presents a survey report on the major perspectives with which energy conservation mechanisms has been proposed in dynamic cluster based WSNs so far. All the solutions discussed in this paper focus on the cluster based protocols only.We have covered a vast scale of existing energy efficient protocols and have categorized them in six categories. In the beginning of this paper the fundamentals of the energy constraint issues of WSNs have been discussed and an overview of the causes of energy consumptions at all layers of WSN has been given. Later in this paper several previously proposed energy efficient protocols of WSNs are presented.

  18. THE EVOLUTION OF DUSTY STAR FORMATION IN GALAXY CLUSTERS TO z = 1: SPITZER INFRARED OBSERVATIONS OF THE FIRST RED-SEQUENCE CLUSTER SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Webb, T. M. A.; O' Donnell, D.; Coppin, Kristen; Faloon, Ashley; Geach, James E.; Noble, Allison [McGill University, 3600 rue University, Montreal, QC, H3A 2T8 (Canada); Yee, H. K. C. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George St., Toronto, ON, M5S 3H4 (Canada); Gilbank, David [South African Astronomical Observatory, P.O. Box 9, Observatory, 7935 (South Africa); Ellingson, Erica [Department of Astrophysical and Planetary Sciences, University of Colorado at Boulder, Boulder, CO 80309 (United States); Gladders, Mike [Department of Astronomy and Astrophysics, University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637 (United States); Muzzin, Adam [Leiden Observatory, University of Leiden, Niels Bohrweg 2, NL-2333 CA, Leiden (Netherlands); Wilson, Gillian [Department of Physics and Astronomy, University of California at Riverside, 900 University Avenue, Riverside, CA 92521 (United States); Yan, Renbin [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)

    2013-10-01

    We present the results of an infrared (IR) study of high-redshift galaxy clusters with the MIPS camera on board the Spitzer Space Telescope. We have assembled a sample of 42 clusters from the Red-Sequence Cluster Survey-1 over the redshift range 0.3 < z < 1.0 and spanning an approximate range in mass of 10{sup 14-15} M {sub ☉}. We statistically measure the number of IR-luminous galaxies in clusters above a fixed inferred IR luminosity of 2 × 10{sup 11} M {sub ☉}, assuming a star forming galaxy template, per unit cluster mass and find it increases to higher redshift. Fitting a simple power-law we measure evolution of (1 + z){sup 5.1±1.9} over the range 0.3 < z < 1.0. These results are tied to the adoption of a single star forming galaxy template; the presence of active galactic nuclei, and an evolution in their relative contribution to the mid-IR galaxy emission, will alter the overall number counts per cluster and their rate of evolution. Under the star formation assumption we infer the approximate total star formation rate per unit cluster mass (ΣSFR/M {sub cluster}). The evolution is similar, with ΣSFR/M {sub cluster} ∼ (1 + z){sup 5.4±1.9}. We show that this can be accounted for by the evolution of the IR-bright field population over the same redshift range; that is, the evolution can be attributed entirely to the change in the in-falling field galaxy population. We show that the ΣSFR/M {sub cluster} (binned over all redshift) decreases with increasing cluster mass with a slope (ΣSFR/M{sub cluster}∼M{sub cluster}{sup -1.5±0.4}) consistent with the dependence of the stellar-to-total mass per unit cluster mass seen locally. The inferred star formation seen here could produce ∼5%-10% of the total stellar mass in massive clusters at z = 0, but we cannot constrain the descendant population, nor how rapidly the star-formation must shut-down once the galaxies have entered the cluster environment. Finally, we show a clear decrease in the number of IR

  19. THE HST/ACS COMA CLUSTER SURVEY. II. DATA DESCRIPTION AND SOURCE CATALOGS

    International Nuclear Information System (INIS)

    Hammer, Derek; Verdoes Kleijn, Gijs; Den Brok, Mark; Peletier, Reynier F.; Hoyos, Carlos; Balcells, Marc; Aguerri, Alfonso L.; Ferguson, Henry C.; Goudfrooij, Paul; Carter, David; Guzman, Rafael; Smith, Russell J.; Lucey, John R.; Graham, Alister W.; Trentham, Neil; Peng, Eric; Puzia, Thomas H.; Jogee, Shardha; Batcheldor, Dan; Bridges, Terry J.

    2010-01-01

    The Coma cluster, Abell 1656, was the target of an HST-ACS Treasury program designed for deep imaging in the F475W and F814W passbands. Although our survey was interrupted by the ACS instrument failure in early 2007, the partially completed survey still covers ∼50% of the core high-density region in Coma. Observations were performed for 25 fields that extend over a wide range of cluster-centric radii (∼1.75 Mpc or 1 0 ) with a total coverage area of 274 arcmin 2 . The majority of the fields are located near the core region of Coma (19/25 pointings) with six additional fields in the southwest region of the cluster. In this paper, we present reprocessed images and SEXTRACTOR source catalogs for our survey fields, including a detailed description of the methodology used for object detection and photometry, the subtraction of bright galaxies to measure faint underlying objects, and the use of simulations to assess the photometric accuracy and completeness of our catalogs. We also use simulations to perform aperture corrections for the SEXTRACTOR Kron magnitudes based only on the measured source flux and its half-light radius. We have performed photometry for ∼73,000 unique objects; approximately one-half of our detections are brighter than the 10σ point-source detection limit at F814W = 25.8 mag (AB). The slight majority of objects (60%) are unresolved or only marginally resolved by ACS. We estimate that Coma members are 5%-10% of all source detections, which consist of a large population of unresolved compact sources (primarily globular clusters but also ultra-compact dwarf galaxies) and a wide variety of extended galaxies from a cD galaxy to dwarf low surface brightness galaxies. The red sequence of Coma member galaxies has a color-magnitude relation with a constant slope and dispersion over 9 mag (-21 F814W < -13). The initial data release for the HST-ACS Coma Treasury program was made available to the public in 2008 August. The images and catalogs described

  20. A NEW Hα EMISSION-LINE SURVEY IN THE ORION NEBULA CLUSTER

    International Nuclear Information System (INIS)

    Szegedi-Elek, E.; Kun, M.; Pál, A.; Balázs, L. G.; Reipurth, B.; Willman, M.

    2013-01-01

    We present results from an Hα emission line survey in a 1 deg 2 area centered on the Orion Nebula Cluster, obtained with the Wide Field Grism Spectrograph 2 on the 2.2 m telescope of the University of Hawaii. We identified 587 stars with Hα emission, 99 of which, located mainly in the outer regions of the observed area, have not appeared in previous Hα surveys. We determined the equivalent width (EW) of the line and, based on this, classified 372 stars as classical T Tauri stars (CTTSs) and 187 as weak-line T Tauri stars (WTTSs). Simultaneous r', i' photometry indicates a limiting magnitude of r' ∼ 20 mag, but the sample is incomplete at r' > 17 mag. The surface distribution of the Hα emission stars reveals a clustered population and a dispersed population, the former consisting of younger and more massive young stars than the latter. Comparison of the derived EWs with those found in the literature indicates variability of the Hα line. We found that the typical amplitudes of the variability are not greater than a factor of two to three in most cases. We identified a subgroup of low-EW stars with infrared signatures indicative of optically thick accretion disks. We studied the correlations between the EW and other properties of the stars. Based on literature data, we examined several properties of our CTTS and WTTS subsamples and found significant differences in mid-infrared color indices, average rotational periods, and spectral energy distribution characteristics of the subsamples

  1. Synthesis of indium-111 mesoprotoporphyrin IX

    International Nuclear Information System (INIS)

    Lee, K.M.; Marshall, A.G.

    1981-01-01

    Indium-111 mesoprotoporphyrin IX has been prepared by refluxing suitable proportions of InCl 3 , sodium acetate, and mesoprotoporphyrin IX in glacial acetic acid. The labeled metalloporphyrin is sufficiently water-soluble for use as a scanning agent, and can also be incorporated into heme apoproteins for perturbed gamma-gamma angular correlation measurements. (author)

  2. A catalogue of clusters of galaxies identified from all sky surveys of 2MASS, WISE, and SuperCOSMOS

    Science.gov (United States)

    Wen, Z. L.; Han, J. L.; Yang, F.

    2018-03-01

    We identify 47 600 clusters of galaxies from photometric data of Two Micron All Sky Survey (2MASS), Wide-field Infrared Survey Explorer (WISE), and SuperCOSMOS, among which 26 125 clusters are recognized for the first time and mostly in the sky outside the Sloan Digital Sky Survey (SDSS) area. About 90 per cent of massive clusters of M500 > 3 × 1014 M⊙ in the redshift range of 0.025 < z < 0.3 have been detected from such survey data, and the detection rate drops down to 50 per cent for clusters with a mass of M500 ˜ 1 × 1014 M⊙. Monte Carlo simulations show that the false detection rate for the whole cluster sample is less than 5 per cent. By cross-matching with ROSAT and XMM-Newton sources, we get 779 new X-ray cluster candidates which have X-ray counterparts within a projected offset of 0.2 Mpc.

  3. Is the Urban Child Health Advantage Declining in Malawi?: Evidence from Demographic and Health Surveys and Multiple Indicator Cluster Surveys.

    Science.gov (United States)

    Lungu, Edgar Arnold; Biesma, Regien; Chirwa, Maureen; Darker, Catherine

    2018-06-01

    In many developing countries including Malawi, health indicators are on average better in urban than in rural areas. This phenomenon has largely prompted Governments to prioritize rural areas in programs to improve access to health services. However, considerable evidence has emerged that some population groups in urban areas may be facing worse health than rural areas and that the urban advantage may be waning in some contexts. We used a descriptive study undertaking a comparative analysis of 13 child health indicators between urban and rural areas using seven data points provided by nationally representative population based surveys-the Malawi Demographic and Health Surveys and Multiple Indicator Cluster Surveys. Rate differences between urban and rural values for selected child health indicators were calculated to denote whether urban-rural differentials showed a trend of declining urban advantage in Malawi. The results show that all forms of child mortality have significantly declined between 1992 and 2015/2016 reflecting successes in child health interventions. Rural-urban comparisons, using rate differences, largely indicate a picture of the narrowing gap between urban and rural areas albeit the extent and pattern vary among child health indicators. Of the 13 child health indicators, eight (neonatal mortality, infant mortality, under-five mortality rates, stunting rate, proportion of children treated for diarrhea and fever, proportion of children sleeping under insecticide-treated nets, and children fully immunized at 12 months) show clear patterns of a declining urban advantage particularly up to 2014. However, U-5MR shows reversal to a significant urban advantage in 2015/2016, and slight increases in urban advantage are noted for infant mortality rate, underweight, full childhood immunization, and stunting rate in 2015/2016. Our findings suggest the need to rethink the policy viewpoint of a disadvantaged rural and much better-off urban in child health

  4. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XV. THE PHOTOMETRIC REDSHIFT ESTIMATION FOR BACKGROUND SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    Raichoor, A.; Mei, S.; Huertas-Company, M.; Licitra, R. [GEPI, Observatoire de Paris, CNRS, Université Paris Diderot, 61 Avenue de l' Observatoire, F-75014 Paris (France); Erben, T.; Hildebrandt, H. [Argelander-Institut für Astronomie, University of Bonn, Auf dem Hügel 71, D-53121 Bonn (Germany); Ilbert, O.; Boissier, S.; Boselli, A. [Aix Marseille Université, CNRS, Laboratoire d' Astrophysique de Marseille, UMR 7326, F-13388 Marseille (France); Ball, N. M.; Côté, P.; Ferrarese, L.; Gwyn, S. D. J.; Kavelaars, J. J. [Herzberg Institute of Astrophysics, National Research Council of Canada, Victoria, BC V9E 2E7 (Canada); Chen, Y.-T. [Insitute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan (China); Cuillandre, J.-C. [Canada-France-Hawaïi Telescope Corporation, Kamuela, HI 96743 (United States); Duc, P. A. [Laboratoire AIM Paris-Saclay, CEA/IRFU/SAp, CNRS/INSU, Université Paris Diderot, F-91191 Gif-sur-Yvette Cedex (France); Durrell, P. R. [Department of Physics and Astronomy, Youngstown State University, Youngstown, OH 44555 (United States); Guhathakurta, P. [UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Lançon, A., E-mail: anand.raichoor@obspm.fr [Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l' Université, F-67000 Strasbourg (France); and others

    2014-12-20

    The Next Generation Virgo Cluster Survey (NGVS) is an optical imaging survey covering 104 deg{sup 2} centered on the Virgo cluster. Currently, the complete survey area has been observed in the u*giz bands and one third in the r band. We present the photometric redshift estimation for the NGVS background sources. After a dedicated data reduction, we perform accurate photometry, with special attention to precise color measurements through point-spread function homogenization. We then estimate the photometric redshifts with the Le Phare and BPZ codes. We add a new prior that extends to i {sub AB} = 12.5 mag. When using the u* griz bands, our photometric redshifts for 15.5 mag ≤ i ≲ 23 mag or z {sub phot} ≲ 1 galaxies have a bias |Δz| < 0.02, less than 5% outliers, a scatter σ{sub outl.rej.}, and an individual error on z {sub phot} that increases with magnitude (from 0.02 to 0.05 and from 0.03 to 0.10, respectively). When using the u*giz bands over the same magnitude and redshift range, the lack of the r band increases the uncertainties in the 0.3 ≲ z {sub phot} ≲ 0.8 range (–0.05 < Δz < –0.02, σ{sub outl.rej} ∼ 0.06, 10%-15% outliers, and z {sub phot.err.} ∼ 0.15). We also present a joint analysis of the photometric redshift accuracy as a function of redshift and magnitude. We assess the quality of our photometric redshifts by comparison to spectroscopic samples and by verifying that the angular auto- and cross-correlation function w(θ) of the entire NGVS photometric redshift sample across redshift bins is in agreement with the expectations.

  5. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XIX. TOMOGRAPHY OF MILKY WAY SUBSTRUCTURES IN THE NGVS FOOTPRINT

    Energy Technology Data Exchange (ETDEWEB)

    Lokhorst, Deborah; Starkenburg, Else; Navarro, Julio F. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1, Canada (Canada); McConnachie, Alan W.; Ferrarese, Laura; Côté, Patrick; Gwyn, Stephen D. J. [National Research Council, Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Liu, Chengze [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Peng, Eric W. [Department of Astronomy, Peking University, Beijing 100871 (China); Cuillandre, Jean-Charles [CEA/IRFU/SAP, Laboratoire AIM Paris-Saclay, CNRS/INSU, Université Paris Diderot, Observatoire de Paris, PSL Research University, F-91191 Gif-sur-Yvette Cedex (France); Guhathakurta, Puragra, E-mail: dml@uvic.ca [Department of Astronomy and Astrophysics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2016-03-10

    The Next Generation Virgo Cluster Survey (NGVS) is a deep u*giz survey targeting the Virgo Cluster of galaxies at 16.5 Mpc. This survey provides high-quality photometry over an ∼100 deg{sup 2} region straddling the constellations of Virgo and Coma Berenices. This sightline through the Milky Way is noteworthy in that it intersects two of the most prominent substructures in the Galactic halo: the Virgo overdensity (VOD) and Sagittarius stellar stream (close to its bifurcation point). In this paper, we use deep u*gi imaging from the NGVS to perform tomography of the VOD and Sagittarius stream using main-sequence turnoff (MSTO) stars as a halo tracer population. The VOD, whose centroid is known to lie at somewhat lower declinations (α ∼ 190°, δ ∼ −5°) than is covered by the NGVS, is nevertheless clearly detected in the NGVS footprint at distances between ∼8 and 25 kpc. By contrast, the Sagittarius stream is found to slice directly across the NGVS field at distances between 25 and 40 kpc, with a density maximum at ≃35 kpc. No evidence is found for new substructures beyond the Sagittarius stream, at least out to a distance of ∼90 kpc—the largest distance to which we can reliably trace the halo using MSTO stars. We find clear evidence for a distance gradient in the Sagittarius stream across the ∼30° of sky covered by the NGVS and its flanking fields. We compare our distance measurements along the stream with those predicted by leading stream models.

  6. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XV. THE PHOTOMETRIC REDSHIFT ESTIMATION FOR BACKGROUND SOURCES

    International Nuclear Information System (INIS)

    Raichoor, A.; Mei, S.; Huertas-Company, M.; Licitra, R.; Erben, T.; Hildebrandt, H.; Ilbert, O.; Boissier, S.; Boselli, A.; Ball, N. M.; Côté, P.; Ferrarese, L.; Gwyn, S. D. J.; Kavelaars, J. J.; Chen, Y.-T.; Cuillandre, J.-C.; Duc, P. A.; Durrell, P. R.; Guhathakurta, P.; Lançon, A.

    2014-01-01

    The Next Generation Virgo Cluster Survey (NGVS) is an optical imaging survey covering 104 deg 2 centered on the Virgo cluster. Currently, the complete survey area has been observed in the u*giz bands and one third in the r band. We present the photometric redshift estimation for the NGVS background sources. After a dedicated data reduction, we perform accurate photometry, with special attention to precise color measurements through point-spread function homogenization. We then estimate the photometric redshifts with the Le Phare and BPZ codes. We add a new prior that extends to i AB = 12.5 mag. When using the u* griz bands, our photometric redshifts for 15.5 mag ≤ i ≲ 23 mag or z phot ≲ 1 galaxies have a bias |Δz| < 0.02, less than 5% outliers, a scatter σ outl.rej. , and an individual error on z phot that increases with magnitude (from 0.02 to 0.05 and from 0.03 to 0.10, respectively). When using the u*giz bands over the same magnitude and redshift range, the lack of the r band increases the uncertainties in the 0.3 ≲ z phot ≲ 0.8 range (–0.05 < Δz < –0.02, σ outl.rej ∼ 0.06, 10%-15% outliers, and z phot.err. ∼ 0.15). We also present a joint analysis of the photometric redshift accuracy as a function of redshift and magnitude. We assess the quality of our photometric redshifts by comparison to spectroscopic samples and by verifying that the angular auto- and cross-correlation function w(θ) of the entire NGVS photometric redshift sample across redshift bins is in agreement with the expectations

  7. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XIX. TOMOGRAPHY OF MILKY WAY SUBSTRUCTURES IN THE NGVS FOOTPRINT

    International Nuclear Information System (INIS)

    Lokhorst, Deborah; Starkenburg, Else; Navarro, Julio F.; McConnachie, Alan W.; Ferrarese, Laura; Côté, Patrick; Gwyn, Stephen D. J.; Liu, Chengze; Peng, Eric W.; Cuillandre, Jean-Charles; Guhathakurta, Puragra

    2016-01-01

    The Next Generation Virgo Cluster Survey (NGVS) is a deep u*giz survey targeting the Virgo Cluster of galaxies at 16.5 Mpc. This survey provides high-quality photometry over an ∼100 deg 2 region straddling the constellations of Virgo and Coma Berenices. This sightline through the Milky Way is noteworthy in that it intersects two of the most prominent substructures in the Galactic halo: the Virgo overdensity (VOD) and Sagittarius stellar stream (close to its bifurcation point). In this paper, we use deep u*gi imaging from the NGVS to perform tomography of the VOD and Sagittarius stream using main-sequence turnoff (MSTO) stars as a halo tracer population. The VOD, whose centroid is known to lie at somewhat lower declinations (α ∼ 190°, δ ∼ −5°) than is covered by the NGVS, is nevertheless clearly detected in the NGVS footprint at distances between ∼8 and 25 kpc. By contrast, the Sagittarius stream is found to slice directly across the NGVS field at distances between 25 and 40 kpc, with a density maximum at ≃35 kpc. No evidence is found for new substructures beyond the Sagittarius stream, at least out to a distance of ∼90 kpc—the largest distance to which we can reliably trace the halo using MSTO stars. We find clear evidence for a distance gradient in the Sagittarius stream across the ∼30° of sky covered by the NGVS and its flanking fields. We compare our distance measurements along the stream with those predicted by leading stream models

  8. The cosmological analysis of X-ray cluster surveys - I. A new method for interpreting number counts

    Science.gov (United States)

    Clerc, N.; Pierre, M.; Pacaud, F.; Sadibekova, T.

    2012-07-01

    We present a new method aimed at simplifying the cosmological analysis of X-ray cluster surveys. It is based on purely instrumental observable quantities considered in a two-dimensional X-ray colour-magnitude diagram (hardness ratio versus count rate). The basic principle is that even in rather shallow surveys, substantial information on cluster redshift and temperature is present in the raw X-ray data and can be statistically extracted; in parallel, such diagrams can be readily predicted from an ab initio cosmological modelling. We illustrate the methodology for the case of a 100-deg2XMM survey having a sensitivity of ˜10-14 erg s-1 cm-2 and fit at the same time, the survey selection function, the cluster evolutionary scaling relations and the cosmology; our sole assumption - driven by the limited size of the sample considered in the case study - is that the local cluster scaling relations are known. We devote special attention to the realistic modelling of the count-rate measurement uncertainties and evaluate the potential of the method via a Fisher analysis. In the absence of individual cluster redshifts, the count rate and hardness ratio (CR-HR) method appears to be much more efficient than the traditional approach based on cluster counts (i.e. dn/dz, requiring redshifts). In the case where redshifts are available, our method performs similar to the traditional mass function (dn/dM/dz) for the purely cosmological parameters, but constrains better parameters defining the cluster scaling relations and their evolution. A further practical advantage of the CR-HR method is its simplicity: this fully top-down approach totally bypasses the tedious steps consisting in deriving cluster masses from X-ray temperature measurements.

  9. THE SLOAN DIGITAL SKY SURVEY CO-ADD: CROSS-CORRELATION WEAK LENSING AND TOMOGRAPHY OF GALAXY CLUSTERS

    International Nuclear Information System (INIS)

    Simet, Melanie; Dodelson, Scott; Kubo, Jeffrey M.; Annis, James T.; Hao Jiangang; Johnston, David; Lin, Huan; Soares-Santos, Marcelle; Reis, Ribamar R. R.; Seo, Hee-Jong

    2012-01-01

    The shapes of distant galaxies are sheared by intervening galaxy clusters. We examine this effect in Stripe 82, a 275 deg 2 region observed multiple times in the Sloan Digital Sky Survey (SDSS) and co-added to achieve greater depth. We obtain a mass-richness calibration that is similar to other SDSS analyses, demonstrating that the co-addition process did not adversely affect the lensing signal. We also propose a new parameterization of the effect of tomography on the cluster lensing signal which does not require binning in redshift, and we show that using this parameterization we can detect tomography for stacked clusters at varying redshifts. Finally, due to the sensitivity of the tomographic detection to accurately marginalize over the effect of the cluster mass, we show that tomography at low redshift (where dependence on exact cosmological models is weak) can be used to constrain mass profiles in clusters.

  10. Alma Survey of Circumstellar Disks in the Young Stellar Cluster IC 348

    Science.gov (United States)

    Ruíz-Rodríguez, D.; Cieza, L. A.; Williams, J. P.; Andrews, S. M.; Principe, D. A.; Caceres, C.; Canovas, H.; Casassus, S.; Schreiber, M. R.; Kastner, J. H.

    2018-05-01

    We present a 1.3 mm continuum survey of the young (2-3 Myr) stellar cluster IC 348, which lies at a distance of 310 pc, and is dominated by low-mass stars (M⋆ ˜ 0.1-0.6 M⊙). We observed 136 Class II sources (disks that are optically thick in the infrared) at 0.8″ (200 au) resolution with a 3σ sensitivity of ˜ 0.45 mJy (Mdust ˜ 1.3 M⊕). We detect 40 of the targets and construct a mm-continuum luminosity function. We compare the disk mass distribution in IC 348 to those of younger and older regions, taking into account the dependence on stellar mass. We find a clear evolution in disk masses from 1 to 5-10 Myr. The disk masses in IC 348 are significantly lower than those in Taurus (1-3 Myr) and Lupus (1-3 Myr), similar to those of Chamaleon I, (2-3 Myr) and σ Ori (3-5 Myr) and significantly higher than in Upper Scorpius (5-10 Myr). About 20 disks in our sample (˜5% of the cluster members) have estimated masses (dust + gas) >1 MJup and hence might be the precursors of giant planets in the cluster. Some of the most massive disks include transition objects with inner opacity holes based on their infrared SEDs. From a stacking analysis of the 96 non-detections, we find that these disks have a typical dust mass of just ≲ 0.4 M⊕, even though the vast majority of their infrared SEDs remain optically thick and show little signs of evolution. Such low-mass disks may be the precursors of the small rocky planets found by Kepler around M-type stars.

  11. MASSIVE+: The Growth Histories of MASSIVE Survey Galaxies from their Globular Cluster Colors

    Science.gov (United States)

    Blakeslee, John

    2017-08-01

    The MASSIVE survey is targeting the 100 most massive galaxies within 108 Mpc that are visible in the northern sky. These most massive galaxies in the present-day universe reside in a surprisingly wide variety of environments, from rich clusters to fossil groups to near isolation. We propose to use WFC3/UVIS and ACS to carry out a deep imaging study of the globular cluster populations around a selected subset of the MASSIVE targets. Though much is known about GC systems of bright galaxies in rich clusters, we know surprisingly little about the effects of environment on these systems. The MASSIVE sample provides a golden opportunity to learn about the systematics of GC systems and what they can tell us about environmental drivers on the evolution of the highest mass galaxies. The most pressing questions to be addressed include: (1) Do isolated giants have the same constant mass fraction of GCs to total halo mass as BCGs of similar luminosity? (2) Do their GC systems show the same color (metallicity) distribution, which is an outcome of the mass spectrum of gas-rich halos during hierarchical growth? (3) Do the GCs in isolated high-mass galaxies follow the same radial distribution versus metallicity as in rich environments (a test of the relative importance of growth by accretion)? (4) Do the GCs of galaxies in sparse environments follow the same mass function? Our proposed second-band imaging will enable us to secure answers to these questions and add enormously to the legacy value of existing HST imaging of the highest mass galaxies in the universe.

  12. Cluster Mass Calibration at High Redshift: HST Weak Lensing Analysis of 13 Distant Galaxy Clusters from the South Pole Telescope Sunyaev-Zel'dovich Survey

    Energy Technology Data Exchange (ETDEWEB)

    Schrabback, T.; et al.

    2016-11-11

    We present an HST/ACS weak gravitational lensing analysis of 13 massive high-redshift (z_median=0.88) galaxy clusters discovered in the South Pole Telescope (SPT) Sunyaev-Zel'dovich Survey. This study is part of a larger campaign that aims to robustly calibrate mass-observable scaling relations over a wide range in redshift to enable improved cosmological constraints from the SPT cluster sample. We introduce new strategies to ensure that systematics in the lensing analysis do not degrade constraints on cluster scaling relations significantly. First, we efficiently remove cluster members from the source sample by selecting very blue galaxies in V-I colour. Our estimate of the source redshift distribution is based on CANDELS data, where we carefully mimic the source selection criteria of the cluster fields. We apply a statistical correction for systematic photometric redshift errors as derived from Hubble Ultra Deep Field data and verified through spatial cross-correlations. We account for the impact of lensing magnification on the source redshift distribution, finding that this is particularly relevant for shallower surveys. Finally, we account for biases in the mass modelling caused by miscentring and uncertainties in the mass-concentration relation using simulations. In combination with temperature estimates from Chandra we constrain the normalisation of the mass-temperature scaling relation ln(E(z) M_500c/10^14 M_sun)=A+1.5 ln(kT/7.2keV) to A=1.81^{+0.24}_{-0.14}(stat.) +/- 0.09(sys.), consistent with self-similar redshift evolution when compared to lower redshift samples. Additionally, the lensing data constrain the average concentration of the clusters to c_200c=5.6^{+3.7}_{-1.8}.

  13. Statistical survey of day-side magnetospheric current flow using Cluster observations: magnetopause

    Directory of Open Access Journals (Sweden)

    E. Liebert

    2017-05-01

    Full Text Available We present a statistical survey of current structures observed by the Cluster spacecraft at high-latitude day-side magnetopause encounters in the close vicinity of the polar cusps. Making use of the curlometer technique and the fluxgate magnetometer data, we calculate the 3-D current densities and investigate the magnetopause current direction, location, and magnitude during varying solar wind conditions. We find that the orientation of the day-side current structures is in accordance with existing magnetopause current models. Based on the ambient plasma properties, we distinguish five different transition regions at the magnetopause surface and observe distinctive current properties for each region. Additionally, we find that the location of currents varies with respect to the onset of the changes in the plasma environment during magnetopause crossings.

  14. Near-infrared imaging survey of faint companions around young dwarfs in the Pleiades cluster

    International Nuclear Information System (INIS)

    Itoh, Yoichi; Funayama, Hitoshi; Hashiguchi, Toshio; Oasa, Yumiko; Hayashi, Masahiko; Fukagawa, Misato; Currie, Thayne

    2011-01-01

    We conducted a near-infrared imaging survey of 11 young dwarfs in the Pleiades cluster using the Subaru Telescope and the near-infrared coronagraph imager. We found ten faint point sources, with magnitudes as faint as 20 mag in the K-band, with around seven dwarfs. Comparison with the Spitzer archive images revealed that a pair of the faint sources around V 1171 Tau is very red in infrared wavelengths, which indicates very low-mass young stellar objects. However, the results of our follow-up proper motion measurements implied that the central star and the faint sources do not share common proper motions, suggesting that they are not physically associated.

  15. THE TYPE II SUPERNOVA RATE IN z {approx} 0.1 GALAXY CLUSTERS FROM THE MULTI-EPOCH NEARBY CLUSTER SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Graham, M. L.; Sand, D. J. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Bildfell, C. J.; Pritchet, C. J. [Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, STN CSC, Victoria BC V8W 3P6 (Canada); Zaritsky, D.; Just, D. W.; Herbert-Fort, S. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Hoekstra, H. [Leiden Observatory, Leiden University, Niels Bohrweg 2, NL-2333 CA Leiden (Netherlands); Sivanandam, S. [Dunlap Institute for Astronomy and Astrophysics, 50 St. George St., Toronto, ON M5S 3H4 (Canada); Foley, R. J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2012-07-01

    We present seven spectroscopically confirmed Type II cluster supernovae (SNe II) discovered in the Multi-Epoch Nearby Cluster Survey, a supernova survey targeting 57 low-redshift 0.05 < z < 0.15 galaxy clusters with the Canada-France-Hawaii Telescope. We find the rate of Type II supernovae within R{sub 200} of z {approx} 0.1 galaxy clusters to be 0.026{sup +0.085}{sub -0.018}(stat){sup +0.003}{sub -0.001}(sys) SNuM. Surprisingly, one SN II is in a red-sequence host galaxy that shows no clear evidence of recent star formation (SF). This is unambiguous evidence in support of ongoing, low-level SF in at least some cluster elliptical galaxies, and illustrates that galaxies that appear to be quiescent cannot be assumed to host only Type Ia SNe. Based on this single SN II we make the first measurement of the SN II rate in red-sequence galaxies, and find it to be 0.007{sup +0.014}{sub -0.007}(stat){sup +0.009}{sub -0.001}(sys) SNuM. We also make the first derivation of cluster specific star formation rates (sSFR) from cluster SN II rates. We find that for all galaxy types the sSFR is 5.1{sup +15.8}{sub -3.1}(stat) {+-} 0.9(sys) M{sub Sun} yr{sup -1} (10{sup 12} M{sub Sun }){sup -1}, and for red-sequence galaxies only it is 2.0{sup +4.2}{sub -0.9}(stat) {+-} 0.4(sys) M{sub Sun} yr{sup -1} (10{sup 12} M{sub Sun }){sup -1}. These values agree with SFRs measured from infrared and ultraviolet photometry, and H{alpha} emission from optical spectroscopy. Additionally, we use the SFR derived from our SNII rate to show that although a small fraction of cluster Type Ia SNe may originate in the young stellar population and experience a short delay time, these results do not preclude the use of cluster SN Ia rates to derive the late-time delay time distribution for SNe Ia.

  16. A NEW Hα EMISSION-LINE SURVEY IN THE ORION NEBULA CLUSTER

    Energy Technology Data Exchange (ETDEWEB)

    Szegedi-Elek, E.; Kun, M.; Pál, A.; Balázs, L. G. [Konkoly Observatory, H-1121 Budapest, Konkoly Thege út 15-17 (Hungary); Reipurth, B.; Willman, M., E-mail: eelza@konkoly.hu [Institute for Astronomy, University of Hawaii at Manoa, 640 N. Aohoku Place, Hilo, HI 96720 (United States)

    2013-10-01

    We present results from an Hα emission line survey in a 1 deg{sup 2} area centered on the Orion Nebula Cluster, obtained with the Wide Field Grism Spectrograph 2 on the 2.2 m telescope of the University of Hawaii. We identified 587 stars with Hα emission, 99 of which, located mainly in the outer regions of the observed area, have not appeared in previous Hα surveys. We determined the equivalent width (EW) of the line and, based on this, classified 372 stars as classical T Tauri stars (CTTSs) and 187 as weak-line T Tauri stars (WTTSs). Simultaneous r', i' photometry indicates a limiting magnitude of r' ∼ 20 mag, but the sample is incomplete at r' > 17 mag. The surface distribution of the Hα emission stars reveals a clustered population and a dispersed population, the former consisting of younger and more massive young stars than the latter. Comparison of the derived EWs with those found in the literature indicates variability of the Hα line. We found that the typical amplitudes of the variability are not greater than a factor of two to three in most cases. We identified a subgroup of low-EW stars with infrared signatures indicative of optically thick accretion disks. We studied the correlations between the EW and other properties of the stars. Based on literature data, we examined several properties of our CTTS and WTTS subsamples and found significant differences in mid-infrared color indices, average rotational periods, and spectral energy distribution characteristics of the subsamples.

  17. ASPECT: A spectra clustering tool for exploration of large spectral surveys

    Science.gov (United States)

    in der Au, A.; Meusinger, H.; Schalldach, P. F.; Newholm, M.

    2012-11-01

    Context. Analysing the empirical output from large surveys is an important challenge in contemporary science. Difficulties arise, in particular, when the database is huge and the properties of the object types to be selected are poorly constrained a priori. Aims: We present the novel, semi-automated clustering tool ASPECT for analysing voluminous archives of spectra. Methods: The heart of the program is a neural network in the form of a Kohonen self-organizing map. The resulting map is designed as an icon map suitable for the inspection by eye. The visual analysis is supported by the option to blend in individual object properties such as redshift, apparent magnitude, or signal-to-noise ratio. In addition, the package provides several tools for the selection of special spectral types, e.g. local difference maps which reflect the deviations of all spectra from one given input spectrum (real or artificial). Results: ASPECT is able to produce a two-dimensional topological map of a huge number of spectra. The software package enables the user to browse and navigate through a huge data pool and helps them to gain an insight into underlying relationships between the spectra and other physical properties and to get the big picture of the entire data set. We demonstrate the capability of ASPECT by clustering the entire data pool of ~6 × 105 spectra from the Data Release 4 of the Sloan Digital Sky Survey (SDSS). To illustrate the results regarding quality and completeness we track objects from existing catalogues of quasars and carbon stars, respectively, and connect the SDSS spectra with morphological information from the GalaxyZoo project. Code is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/547/A115

  18. Evolution of galaxies clustering in the VIMOS-VLT Deep Survey

    International Nuclear Information System (INIS)

    Meneux, Baptiste

    2005-01-01

    The recent surveys of the Universe highlighted the presence of structures in the matter distribution, such as filaments and voids. To study the evolution of the galaxy spatial distribution, it is necessary to know their accurate position in a three dimensional space. This thesis took place within the framework of the VIMOS-VLT Deep Survey (VVDS). Its goal is to measure some 100000 redshifts to study the formation and evolution of the galaxies and large scale structures of the Universe up to z∼5. After having made a review of our knowledge of the galaxies distribution, then introduced the VVDS, I present the measurement and the evolution of the real-space two-point correlation function from the first epoch data of the VVDS, the largest sample of 10759 spectra ever acquired up to I_A_B = 24. I developed a whole set of programs made available to the VVDS consortium to easily measure the clustering length of galaxies in a given redshift range, with its associated errors, correcting the effects of the VVDS observing strategy. This tool enabled to measure the evolution of the real space correlation function of the global galaxies population up to z=2. I then extended this study dividing the full galaxies sample by spectral type and color. Finally, combining the GALEX data to the VVDS has allowed me to measure the clustering of an ultraviolet-selected sample of galaxies up to z∼1. This is the first time that such measurements are carried out on such a so long range of cosmic time. The results presented in this thesis are thus establishing a new reference in the field. (author) [fr

  19. Legacy ExtraGalactic UV Survey with The Hubble Space Telescope: Stellar Cluster Catalogs and First Insights Into Cluster Formation and Evolution in NGC 628

    Science.gov (United States)

    Adamo, A.; Ryon, J. E.; Messa, M.; Kim, H.; Grasha, K.; Cook, D. O.; Calzetti, D.; Lee, J. C.; Whitmore, B. C.; Elmegreen, B. G.; Ubeda, L.; Smith, L. J.; Bright, S. N.; Runnholm, A.; Andrews, J. E.; Fumagalli, M.; Gouliermis, D. A.; Kahre, L.; Nair, P.; Thilker, D.; Walterbos, R.; Wofford, A.; Aloisi, A.; Ashworth, G.; Brown, T. M.; Chandar, R.; Christian, C.; Cignoni, M.; Clayton, G. C.; Dale, D. A.; de Mink, S. E.; Dobbs, C.; Elmegreen, D. M.; Evans, A. S.; Gallagher, J. S., III; Grebel, E. K.; Herrero, A.; Hunter, D. A.; Johnson, K. E.; Kennicutt, R. C.; Krumholz, M. R.; Lennon, D.; Levay, K.; Martin, C.; Nota, A.; Östlin, G.; Pellerin, A.; Prieto, J.; Regan, M. W.; Sabbi, E.; Sacchi, E.; Schaerer, D.; Schiminovich, D.; Shabani, F.; Tosi, M.; Van Dyk, S. D.; Zackrisson, E.

    2017-06-01

    We report the large effort that is producing comprehensive high-level young star cluster (YSC) catalogs for a significant fraction of galaxies observed with the Legacy ExtraGalactic UV Survey (LEGUS) Hubble treasury program. We present the methodology developed to extract cluster positions, verify their genuine nature, produce multiband photometry (from NUV to NIR), and derive their physical properties via spectral energy distribution fitting analyses. We use the nearby spiral galaxy NGC 628 as a test case for demonstrating the impact that LEGUS will have on our understanding of the formation and evolution of YSCs and compact stellar associations within their host galaxy. Our analysis of the cluster luminosity function from the UV to the NIR finds a steepening at the bright end and at all wavelengths suggesting a dearth of luminous clusters. The cluster mass function of NGC 628 is consistent with a power-law distribution of slopes ˜ -2 and a truncation of a few times 105 {M}⊙ . After their formation, YSCs and compact associations follow different evolutionary paths. YSCs survive for a longer time frame, confirming their being potentially bound systems. Associations disappear on timescales comparable to hierarchically organized star-forming regions, suggesting that they are expanding systems. We find mass-independent cluster disruption in the inner region of NGC 628, while in the outer part of the galaxy there is little or no disruption. We observe faster disruption rates for low mass (≤104 {M}⊙ ) clusters, suggesting that a mass-dependent component is necessary to fully describe the YSC disruption process in NGC 628. Based on observations obtained with the NASA/ESA Hubble Space Telescope, at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  20. The HST/ACS Coma Cluster Survey. II. Data Description and Source Catalogs

    Science.gov (United States)

    Hammer, Derek; Kleijn, Gijs Verdoes; Hoyos, Carlos; Den Brok, Mark; Balcells, Marc; Ferguson, Henry C.; Goudfrooij, Paul; Carter, David; Guzman, Rafael; Peletier, Reynier F.; hide

    2010-01-01

    The Coma cluster, Abell 1656, was the target of a HST-ACS Treasury program designed for deep imaging in the F475W and F814W passbands. Although our survey was interrupted by the ACS instrument failure in early 2007, the partially-completed survey still covers approximately 50% of the core high density region in Coma. Observations were performed for twenty-five fields with a total coverage area of 274 aremin(sup 2), and extend over a wide range of cluster-centric radii (approximately 1.75 Mpe or 1 deg). The majority of the fields are located near the core region of Coma (19/25 pointings) with six additional fields in the south-west region of the cluster. In this paper we present SEXTRACTOR source catalogs generated from the processed images, including a detailed description of the methodology used for object detection and photometry, the subtraction of bright galaxies to measure faint underlying objects, and the use of simulations to assess the photometric accuracy and completeness of our catalogs. We also use simulations to perform aperture corrections for the SEXTRACTOR Kron magnitudes based only on the measured source flux and its half-light radius. We have performed photometry for 76,000 objects that consist of roughly equal numbers of extended galaxies and unresolved objects. Approximately two-thirds of all detections are brighter than F814W=26.5 mag (AB), which corresponds to the 10sigma, point-source detection limit. We estimate that Coma members are 5-10% of the source detections, including a large population of compact objects (primarily GCs, but also cEs and UCDs), and a wide variety of extended galaxies from cD galaxies to dwarf low surface brightness galaxies. The initial data release for the HST-ACS Coma Treasury program was made available to the public in August 2008. The images and catalogs described in this study relate to our second data release.

  1. A spectroscopic survey of EC4, an extended cluster in Andromeda's halo

    Science.gov (United States)

    Collins, M. L. M.; Chapman, S. C.; Irwin, M.; Ibata, R.; Martin, N. F.; Ferguson, A. M. N.; Huxor, A.; Lewis, G. F.; Mackey, A. D.; McConnachie, A. W.; Tanvir, N.

    2009-07-01

    We present a spectroscopic survey of candidate red giant branch stars in the extended star cluster, EC4, discovered in the halo of M31 from our Canada-France-Hawaii Telescope/MegaCam survey, overlapping the tidal streams, Streams`Cp' and `Cr'. These observations used the DEep Imaging Multi-Object Spectrograph mounted on the Keck II telescope to obtain spectra around the CaII triplet region with ~1.3 Å resolution. Six stars lying on the red giant branch within two core radii of the centre of EC4 are found to have an average vr = -287.9+1.9-2.4kms-1 and σv,corr = 2.7+4.2-2.7kms-1, taking instrumental errors into account. The resulting mass-to-light ratio for EC4 is M/L = 6.7+15-6.7Msolar/Lsolar, a value that is consistent with a globular cluster within the 1σ errors we derive. From the summed spectra of our member stars, we find EC4 to be metal-poor, with [Fe/H] = -1.6 +/- 0.15. We discuss several formation and evolution scenarios which could account for our kinematic and metallicity constraints on EC4, and conclude that EC4 is most comparable with an extended globular cluster. We also compare the kinematics and metallicity of EC4 with Streams `Cp' and`Cr', and find that EC4 bears a striking resemblance to Stream`Cp' in terms of velocity, and that the two structures are identical in terms of both their spectroscopic and photometric metallicities. From this, we conclude that EC4 is likely related to Stream`Cp'. The data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. E-mail: mlmc2@ast.cam.ac.uk

  2. Sloan Digital Sky Survey III photometric quasar clustering: probing the initial conditions of the Universe

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Shirley; Agarwal, Nishant; Lyons, Richard; Disbrow, Ashley; O' Connell, Ross [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Seo, Hee-Jong; Schlegel, David; Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94702 (United States); Ross, Ashley [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX (United Kingdom); Hirata, Christopher; Huff, Eric; Weinberg, David [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Padmanabhan, Nikhil [Department of Physics and Astronomy, Yale University, New Haven, CT 06520 (United States); Slosar, Anže [Brookhaven National Laboratory, Bldg. 510, Upton NY 11375 (United States); Strauss, Michael; Bahcall, Neta [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Brinkmann, J. [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059 (United States); Palanque-Delabrouille, Nathalie, E-mail: shirleyh@andrew.cmu.edu [CEA, Centre de Saclay, Irfu/SPP, F-91191 Gif-sur-Yvette (France); and others

    2015-05-01

    The Sloan Digital Sky Survey has surveyed 14,555 square degrees of the sky, and delivered over a trillion pixels of imaging data. We present the large-scale clustering of 1.6 million quasars between z=0.5 and z=2.5 that have been classified from this imaging, representing the highest density of quasars ever studied for clustering measurements. This data set spans 0∼ 11,00 square degrees and probes a volume of 80 h{sup −3} Gpc{sup 3}. In principle, such a large volume and medium density of tracers should facilitate high-precision cosmological constraints. We measure the angular clustering of photometrically classified quasars using an optimal quadratic estimator in four redshift slices with an accuracy of ∼ 25% over a bin width of δ{sub l} ∼ 10−15 on scales corresponding to matter-radiation equality and larger (0ℓ ∼ 2−3). Observational systematics can strongly bias clustering measurements on large scales, which can mimic cosmologically relevant signals such as deviations from Gaussianity in the spectrum of primordial perturbations. We account for systematics by employing a new method recently proposed by Agarwal et al. (2014) to the clustering of photometrically classified quasars. We carefully apply our methodology to mitigate known observational systematics and further remove angular bins that are contaminated by unknown systematics. Combining quasar data with the photometric luminous red galaxy (LRG) sample of Ross et al. (2011) and Ho et al. (2012), and marginalizing over all bias and shot noise-like parameters, we obtain a constraint on local primordial non-Gaussianity of f{sub NL} = −113{sup +154}{sub −154} (1σ error). We next assume that the bias of quasar and galaxy distributions can be obtained independently from quasar/galaxy-CMB lensing cross-correlation measurements (such as those in Sherwin et al. (2013)). This can be facilitated by spectroscopic observations of the sources, enabling the redshift distribution to be

  3. Centre-excised X-ray luminosity as an efficient mass proxy for future galaxy cluster surveys

    Science.gov (United States)

    Mantz, Adam B.; Allen, Steven W.; Morris, R. Glenn; von der Linden, Anja

    2018-01-01

    The cosmological constraining power of modern galaxy cluster catalogues can be improved by obtaining low-scatter mass proxy measurements for even a small fraction of sources. In the context of large upcoming surveys that will reveal the cluster population down to the group scale and out to high redshifts, efficient strategies for obtaining such mass proxies will be valuable. In this work, we use high-quality weak-lensing and X-ray mass estimates for massive clusters in current X-ray-selected catalogues to revisit the scaling relations of the projected, centre-excised X-ray luminosity (Lce), which previous work suggests correlates tightly with total mass. Our data confirm that this is the case with Lce having an intrinsic scatter at fixed mass comparable to that of gas mass, temperature or YX. Compared to the other proxies, however, Lce is less susceptible to systematic uncertainties due to background modelling, and can be measured precisely with shorter exposures. This opens up the possibility of using Lce to estimate masses for large numbers of clusters discovered by new X-ray surveys (e.g. eROSITA) directly from the survey data, as well as for clusters discovered at other wavelengths with relatively short follow-up observations. We describe a simple procedure for making such estimates from X-ray surface brightness data, and comment on the spatial resolution required to apply this method as a function of cluster mass and redshift. We also explore the potential impact of Chandra and XMM-Newton follow-up observations over the next decade on dark energy constraints from new cluster surveys.

  4. The ALHAMBRA survey: evolution of galaxy clustering since z ˜ 1

    Science.gov (United States)

    Arnalte-Mur, P.; Martínez, V. J.; Norberg, P.; Fernández-Soto, A.; Ascaso, B.; Merson, A. I.; Aguerri, J. A. L.; Castander, F. J.; Hurtado-Gil, L.; López-Sanjuan, C.; Molino, A.; Montero-Dorta, A. D.; Stefanon, M.; Alfaro, E.; Aparicio-Villegas, T.; Benítez, N.; Broadhurst, T.; Cabrera-Caño, J.; Cepa, J.; Cerviño, M.; Cristóbal-Hornillos, D.; del Olmo, A.; González Delgado, R. M.; Husillos, C.; Infante, L.; Márquez, I.; Masegosa, J.; Moles, M.; Perea, J.; Pović, M.; Prada, F.; Quintana, J. M.

    2014-06-01

    We study the clustering of galaxies as function of luminosity and redshift in the range 0.35 work cover 2.38 deg2 in seven independent fields, after applying a detailed angular selection mask, with accurate photometric redshifts, σz ≲ 0.014(1 + z), down to IAB accounting for photometric redshifts uncertainties. We infer the galaxy bias, and study its evolution with luminosity. We study the effect of sample variance, and confirm earlier results that the Cosmic Evolution Survey (COSMOS) and European Large Area ISO Survey North 1 (ELAIS-N1) fields are dominated by the presence of large structures. For the intermediate and bright samples, Lmed ≳ 0.6L*, we obtain a strong dependence of bias on luminosity, in agreement with previous results at similar redshift. We are able to extend this study to fainter luminosities, where we obtain an almost flat relation, similar to that observed at low redshift. Regarding the evolution of bias with redshift, our results suggest that the different galaxy populations studied reside in haloes covering a range in mass between log10[Mh/( h-1 M⊙)] ≳ 11.5 for samples with Lmed ≃ 0.3L* and log10[Mh/( h-1 M⊙)] ≳ 13.0 for samples with Lmed ≃ 2L*, with typical occupation numbers in the range of ˜1-3 galaxies per halo.

  5. The Next Generation Virgo Cluster Survey. XXVIII. Characterization of the Galactic White Dwarf Population

    Energy Technology Data Exchange (ETDEWEB)

    Fantin, Nicholas J. [Department of Physics and Astronomy,University of Victoria, Victoria, BC, V8P 1A1 (Canada); Côté, Patrick; Gwyn, S. D. J.; Ferrarese, Laura; McConnachie, Alan [National Research Council of Canada, Herzberg Astronomy and Astrophysics Program, 5071 W. Saanich Road, Victoria, BC, V9E 2E7 (Canada); Hanes, David A. [Queen’s University, Department of Physics, Engineering Physics and Astronomy, Kingston, Ontario (Canada); Bianchi, Luciana [Department of Physics and Astronomy, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Cuillandre, Jean-Charles [CEA/IRFU/SAp, Laboratoire AIM Paris-Saclay, CNRS/INSU, Université Paris Diderot, Observatoire de Paris, PSL Research University, F-91191 Gif-sur-Yvette Cedex (France); Starkenburg, Else, E-mail: nfantin@uvic.ca [Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany)

    2017-07-01

    We use three different techniques to identify hundreds of white dwarf (WD) candidates in the Next Generation Virgo Cluster Survey (NGVS) based on photometry from the NGVS and GUViCS, and proper motions derived from the NGVS and the Sloan Digital Sky Survey (SDSS). Photometric distances for these candidates are calculated using theoretical color–absolute magnitude relations, while effective temperatures are measured by fitting their spectral energy distributions. Disk and halo WD candidates are separated using a tangential velocity cut of 200 km s{sup −1} in a reduced proper motion diagram, which leads to a sample of six halo WD candidates. Cooling ages, calculated for an assumed WD mass of 0.6 M {sub ⊙}, range between 60 Myr and 6 Gyr, although these estimates depend sensitively on the adopted mass. Luminosity functions for the disk and halo subsamples are constructed and compared to previous results from the SDSS and SuperCOSMOS survey. We compute a number density of (2.81 ± 0.52) × 10{sup −3} pc{sup −3} for the disk WD population—consistent with previous measurements. We find (7.85 ± 4.55) × 10{sup −6} pc{sup −3} for the halo, or 0.3% of the disk. Observed stellar counts are also compared to predictions made by the TRILEGAL and Besançon stellar population synthesis models. The comparison suggests that the TRILEGAL model overpredicts the total number of WDs. The WD counts predicted by the Besançon model agree with the observations, although a discrepancy arises when comparing the predicted and observed halo WD populations; the difference is likely due to the WD masses in the adopted model halo.

  6. THE IMACS CLUSTER BUILDING SURVEY. III. THE STAR FORMATION HISTORIES OF FIELD GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Oemler, Augustus Jr.; Dressler, Alan [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101-1292 (United States); Gladders, Michael G.; Abramson, Louis [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Fritz, Jacopo [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Poggianti, Bianca M.; Vulcani, Benedetta [INAF-Osservatorio Astronomico di Padova, vicolo dell' Osservatorio 5, I-35122 Padova (Italy)

    2013-06-10

    Using data from the IMACS Cluster Building Survey and from nearby galaxy surveys, we examine the evolution of the rate of star formation in field galaxies from z = 0.60 to the present. Fitting the luminosity function to a standard Schechter form, we find a rapid evolution of M{sub B}{sup *} consistent with that found in other deep surveys; at the present epoch M{sub B}{sup *} is evolving at the rate of 0.38 Gyr{sup -1}, several times faster than the predictions of simple models for the evolution of old, coeval galaxies. The evolution of the distribution of specific star formation rates (SSFRs) is also too rapid to explain by such models. We demonstrate that starbursts cannot, even in principle, explain the evolution of the SSFR distribution. However, the rapid evolution of both M{sub B}{sup *} and the SSFR distribution can be explained if some fraction of galaxies have star formation rates characterized by both short rise and fall times and by an epoch of peak star formation more recent than the majority of galaxies. Although galaxies of every stellar mass up to 1.4 Multiplication-Sign 10{sup 11} M{sub Sun} show a range of epochs of peak star formation, the fraction of ''younger'' galaxies falls from about 40% at a mass of 4 Multiplication-Sign 10{sup 10} M{sub Sun} to zero at a mass of 1.4 Multiplication-Sign 10{sup 11} M{sub Sun }. The incidence of younger galaxies appears to be insensitive to the density of the local environment; but does depend on group membership: relatively isolated galaxies are much more likely to be young than are group members.

  7. Evolution of cluster X-ray luminosities and radii: Results from the 160 square degree rosat survey

    DEFF Research Database (Denmark)

    Vikhlinin, A.; McNamara, B.R.; Forman, W.

    1998-01-01

    We searched for cluster X-ray luminosity and radius evolution using our sample of 203 galaxy clusters detected in the 160 deg(2) survey with the ROSAT PSPC (Vikhlinin et al.). With such a large area survey, it is possible, for the first time with ROSAT, to test the evolution of luminous clusters, L......-X > 3 x 10(44) ergs s(-1) in the 0.5-2 keV band. We detect a factor of 3-4 deficit of such luminous clusters at z > 0.3 compared with the present. The evolution is much weaker or absent at modestly lower luminosities, (1-3) x 10(44) ergs s(-1). At still lower luminosities, we find no evolution from...... the analysis of the log N-log S relation. The results in the two upper L, bins are in agreement with the Einstein Extended Medium-Sensitivity Survey evolution result (Gioia et al.; Henry ct al.), which was obtained using a completely independent cluster sample. The low-L-X results are in agreement with other...

  8. TESTING STELLAR POPULATION SYNTHESIS MODELS WITH SLOAN DIGITAL SKY SURVEY COLORS OF M31's GLOBULAR CLUSTERS

    International Nuclear Information System (INIS)

    Peacock, Mark B.; Zepf, Stephen E.; Maccarone, Thomas J.; Kundu, Arunav

    2011-01-01

    Accurate stellar population synthesis models are vital in understanding the properties and formation histories of galaxies. In order to calibrate and test the reliability of these models, they are often compared with observations of star clusters. However, relatively little work has compared these models in the ugriz filters, despite the recent widespread use of this filter set. In this paper, we compare the integrated colors of globular clusters in the Sloan Digital Sky Survey (SDSS) with those predicted from commonly used simple stellar population (SSP) models. The colors are based on SDSS observations of M31's clusters and provide the largest population of star clusters with accurate photometry available from the survey. As such, it is a unique sample with which to compare SSP models with SDSS observations. From this work, we identify a significant offset between the SSP models and the clusters' g - r colors, with the models predicting colors which are too red by g - r ∼ 0.1. This finding is consistent with previous observations of luminous red galaxies in the SDSS, which show a similar discrepancy. The identification of this offset in globular clusters suggests that it is very unlikely to be due to a minority population of young stars. The recently updated SSP model of Maraston and Stroembaeck better represents the observed g - r colors. This model is based on the empirical MILES stellar library, rather than theoretical libraries, suggesting an explanation for the g - r discrepancy.

  9. THE MULTI-EPOCH NEARBY CLUSTER SURVEY: TYPE Ia SUPERNOVA RATE MEASUREMENT IN z {approx} 0.1 CLUSTERS AND THE LATE-TIME DELAY TIME DISTRIBUTION

    Energy Technology Data Exchange (ETDEWEB)

    Sand, David J.; Graham, Melissa L. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Bildfell, Chris; Pritchet, Chris [Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, STN CSC, Victoria BC V8W 3P6 (Canada); Zaritsky, Dennis; Just, Dennis W.; Herbert-Fort, Stephane [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Hoekstra, Henk [Leiden Observatory, Leiden University, Niels Bohrweg 2, NL-2333 CA Leiden (Netherlands); Sivanandam, Suresh [Dunlap Institute for Astronomy and Astrophysics, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Foley, Ryan J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Mahdavi, Andisheh, E-mail: dsand@lcogt.net [Department of Physics and Astronomy, San Francisco State University, San Francisco, CA 94132 (United States)

    2012-02-20

    We describe the Multi-Epoch Nearby Cluster Survey, designed to measure the cluster Type Ia supernova (SN Ia) rate in a sample of 57 X-ray selected galaxy clusters, with redshifts of 0.05 < z < 0.15. Utilizing our real-time analysis pipeline, we spectroscopically confirmed twenty-three cluster SNe Ia, four of which were intracluster events. Using our deep Canada-France-Hawaii Telescope/MegaCam imaging, we measured total stellar luminosities in each of our galaxy clusters, and we performed detailed supernova (SN) detection efficiency simulations. Bringing these ingredients together, we measure an overall cluster SN Ia rate within R{sub 200} (1 Mpc) of 0.042{sup +0.012}{sub -0.010}{sup +0.010}{sub -0.008} SNuM (0.049{sup +0.016}{sub -0.014}{sup +0.005}{sub -0.004} SNuM) and an SN Ia rate within red-sequence galaxies of 0.041{sup +0.015}{sub -0.015}{sup +0.005}{sub -0.010} SNuM (0.041{sup +0.019}{sub -0.015}{sup +0.005}{sub -0.004} SNuM). The red-sequence SN Ia rate is consistent with published rates in early-type/elliptical galaxies in the 'field'. Using our red-sequence SN Ia rate, and other cluster SN measurements in early-type galaxies up to z {approx} 1, we derive the late-time (>2 Gyr) delay time distribution (DTD) of SN Ia assuming a cluster early-type galaxy star formation epoch of z{sub f} = 3. Assuming a power-law form for the DTD, {Psi}(t){proportional_to}t{sup s} , we find s = -1.62 {+-} 0.54. This result is consistent with predictions for the double degenerate SN Ia progenitor scenario (s {approx} -1) and is also in line with recent calculations for the double detonation explosion mechanism (s {approx} -2). The most recent calculations of the single degenerate scenario DTD predicts an order-of-magnitude drop-off in SN Ia rate {approx}6-7 Gyr after stellar formation, and the observed cluster rates cannot rule this out.

  10. The Gaia-ESO Survey: open clusters in Gaia-DR1 . A way forward to stellar age calibration

    Science.gov (United States)

    Randich, S.; Tognelli, E.; Jackson, R.; Jeffries, R. D.; Degl'Innocenti, S.; Pancino, E.; Re Fiorentin, P.; Spagna, A.; Sacco, G.; Bragaglia, A.; Magrini, L.; Prada Moroni, P. G.; Alfaro, E.; Franciosini, E.; Morbidelli, L.; Roccatagliata, V.; Bouy, H.; Bravi, L.; Jiménez-Esteban, F. M.; Jordi, C.; Zari, E.; Tautvaišiene, G.; Drazdauskas, A.; Mikolaitis, S.; Gilmore, G.; Feltzing, S.; Vallenari, A.; Bensby, T.; Koposov, S.; Korn, A.; Lanzafame, A.; Smiljanic, R.; Bayo, A.; Carraro, G.; Costado, M. T.; Heiter, U.; Hourihane, A.; Jofré, P.; Lewis, J.; Monaco, L.; Prisinzano, L.; Sbordone, L.; Sousa, S. G.; Worley, C. C.; Zaggia, S.

    2018-05-01

    Context. Determination and calibration of the ages of stars, which heavily rely on stellar evolutionary models, are very challenging, while representing a crucial aspect in many astrophysical areas. Aims: We describe the methodologies that, taking advantage of Gaia-DR1 and the Gaia-ESO Survey data, enable the comparison of observed open star cluster sequences with stellar evolutionary models. The final, long-term goal is the exploitation of open clusters as age calibrators. Methods: We perform a homogeneous analysis of eight open clusters using the Gaia-DR1 TGAS catalogue for bright members and information from the Gaia-ESO Survey for fainter stars. Cluster membership probabilities for the Gaia-ESO Survey targets are derived based on several spectroscopic tracers. The Gaia-ESO Survey also provides the cluster chemical composition. We obtain cluster parallaxes using two methods. The first one relies on the astrometric selection of a sample of bona fide members, while the other one fits the parallax distribution of a larger sample of TGAS sources. Ages and reddening values are recovered through a Bayesian analysis using the 2MASS magnitudes and three sets of standard models. Lithium depletion boundary (LDB) ages are also determined using literature observations and the same models employed for the Bayesian analysis. Results: For all but one cluster, parallaxes derived by us agree with those presented in Gaia Collaboration (2017, A&A, 601, A19), while a discrepancy is found for NGC 2516; we provide evidence supporting our own determination. Inferred cluster ages are robust against models and are generally consistent with literature values. Conclusions: The systematic parallax errors inherent in the Gaia DR1 data presently limit the precision of our results. Nevertheless, we have been able to place these eight clusters onto the same age scale for the first time, with good agreement between isochronal and LDB ages where there is overlap. Our approach appears promising

  11. THE XMM CLUSTER SURVEY: THE BUILD-UP OF STELLAR MASS IN BRIGHTEST CLUSTER GALAXIES AT HIGH REDSHIFT

    International Nuclear Information System (INIS)

    Stott, J. P.; Collins, C. A.; Hilton, M.; Capozzi, D.; Sahlen, M.; Lloyd-Davies, E.; Hosmer, M.; Liddle, A. R.; Mehrtens, N.; Romer, A. K.; Miller, C. J.; Stanford, S. A.; Viana, P. T. P.; Davidson, M.; Hoyle, B.; Kay, S. T.; Nichol, R. C.

    2010-01-01

    We present deep J- and K s -band photometry of 20 high redshift galaxy clusters between z = 0.8 and1.5, 19 of which are observed with the MOIRCS instrument on the Subaru telescope. By using near-infrared light as a proxy for stellar mass we find the surprising result that the average stellar mass of Brightest Cluster Galaxies (BCGs) has remained constant at ∼9 x 10 11 M sun since z ∼ 1.5. We investigate the effect on this result of differing star formation histories generated by three well-known and independent stellar population codes and find it to be robust for reasonable, physically motivated choices of age and metallicity. By performing Monte Carlo simulations we find that the result is unaffected by any correlation between BCG mass and cluster mass in either the observed or model clusters. The large stellar masses imply that the assemblage of these galaxies took place at the same time as the initial burst of star formation. This result leads us to conclude that dry merging has had little effect on the average stellar mass of BCGs over the last 9-10 Gyr in stark contrast to the predictions of semi-analytic models, based on the hierarchical merging of dark matter halos, which predict a more protracted mass build-up over a Hubble time. However, we discuss that there is potential for reconciliation between observation and theory if there is a significant growth of material in the intracluster light over the same period.

  12. THE MULTI-EPOCH NEARBY CLUSTER SURVEY: TYPE Ia SUPERNOVA RATE MEASUREMENT IN z ∼ 0.1 CLUSTERS AND THE LATE-TIME DELAY TIME DISTRIBUTION

    International Nuclear Information System (INIS)

    Sand, David J.; Graham, Melissa L.; Bildfell, Chris; Pritchet, Chris; Zaritsky, Dennis; Just, Dennis W.; Herbert-Fort, Stéphane; Hoekstra, Henk; Sivanandam, Suresh; Foley, Ryan J.; Mahdavi, Andisheh

    2012-01-01

    We describe the Multi-Epoch Nearby Cluster Survey, designed to measure the cluster Type Ia supernova (SN Ia) rate in a sample of 57 X-ray selected galaxy clusters, with redshifts of 0.05 200 (1 Mpc) of 0.042 +0.012 –0.010 +0.010 –0.008 SNuM (0.049 +0.016 –0.014 +0.005 –0.004 SNuM) and an SN Ia rate within red-sequence galaxies of 0.041 +0.015 –0.015 +0.005 –0.010 SNuM (0.041 +0.019 –0.015 +0.005 –0.004 SNuM). The red-sequence SN Ia rate is consistent with published rates in early-type/elliptical galaxies in the 'field'. Using our red-sequence SN Ia rate, and other cluster SN measurements in early-type galaxies up to z ∼ 1, we derive the late-time (>2 Gyr) delay time distribution (DTD) of SN Ia assuming a cluster early-type galaxy star formation epoch of z f = 3. Assuming a power-law form for the DTD, Ψ(t)∝t s , we find s = –1.62 ± 0.54. This result is consistent with predictions for the double degenerate SN Ia progenitor scenario (s ∼ –1) and is also in line with recent calculations for the double detonation explosion mechanism (s ∼ –2). The most recent calculations of the single degenerate scenario DTD predicts an order-of-magnitude drop-off in SN Ia rate ∼6-7 Gyr after stellar formation, and the observed cluster rates cannot rule this out.

  13. A CFH12k lensing survey of X-ray luminous galaxy clusters - II. Weak lensing analysis and global correlations

    NARCIS (Netherlands)

    Bardeau, S.; Soucail, G.; Kneib, J.-P.; Czoske, O.; Ebeling, H.; Hudelot, P.; Smail, I.; Smith, G. P.

    Aims. We present a wide-field multi-color survey of a homogeneous sample of eleven clusters of galaxies for which we measure total masses and mass distributions from weak lensing. This sample, spanning a small range in both X-ray luminosity and redshift, is ideally suited to determining the

  14. The dependence of galaxy clustering on tidal environment in the Sloan Digital Sky Survey

    Science.gov (United States)

    Paranjape, Aseem; Hahn, Oliver; Sheth, Ravi K.

    2018-06-01

    The influence of the Cosmic Web on galaxy formation and evolution is of great observational and theoretical interest. We investigate whether the Cosmic Web leaves an imprint in the spatial clustering of galaxies in the Sloan Digital Sky Survey (SDSS), using the group catalogue of Yang et al. and tidal field estimates at ˜2 h-1 Mpc scales from the mass-tides-velocity data set of Wang et al. We use the tidal anisotropy α (Paranjape et al.) to characterize the tidal environment of groups, and measure the redshift-space 2-point correlation function (2pcf) of group positions and the luminosity- and colour-dependent clustering of group galaxies using samples segregated by α. We find that all the 2pcf measurements depend strongly on α, with factors of ˜20 between the large-scale 2pcf of objects in the most and least isotropic environments. To test whether these strong trends imply `beyond halo mass' effects for galaxy evolution, we compare our results with corresponding 2pcf measurements in mock catalogues constructed using a halo occupation distribution that uses only halo mass as an input. We find that this prescription qualitatively reproduces all observed trends, and also quantitatively matches many of the observed results. Although there are some statistically significant differences between our `halo mass only' mocks and the data - in the most and least isotropic environments - which deserve further investigation, our results suggest that if the tidal environment induces additional effects on galaxy properties other than those inherited from their host haloes, then these must be weak.

  15. New variable stars discovered in the fields of three Galactic open clusters using the VVV survey

    Science.gov (United States)

    Palma, T.; Minniti, D.; Dékány, I.; Clariá, J. J.; Alonso-García, J.; Gramajo, L. V.; Ramírez Alegría, S.; Bonatto, C.

    2016-11-01

    This project is a massive near-infrared (NIR) search for variable stars in highly reddened and obscured open cluster (OC) fields projected on regions of the Galactic bulge and disk. The search is performed using photometric NIR data in the J-, H- and Ks- bands obtained from the Vista Variables in the Vía Láctea (VVV) Survey. We performed in each cluster field a variability search using Stetson's variability statistics to select the variable candidates. Later, those candidates were subjected to a frequency analysis using the Generalized Lomb-Scargle and the Phase Dispersion Minimization algorithms. The number of independent observations range between 63 and 73. The newly discovered variables in this study, 157 in total in three different known OCs, are classified based on their light curve shapes, periods, amplitudes and their location in the corresponding color-magnitude (J -Ks ,Ks) and color-color (H -Ks , J - H) diagrams. We found 5 possible Cepheid stars which, based on the period-luminosity relation, are very likely type II Cepheids located behind the bulge. Among the newly discovered variables, there are eclipsing binaries, δ Scuti, as well as background RR Lyrae stars. Using the new version of the Wilson & Devinney code as well as the "Physics Of Eclipsing Binaries" (PHOEBE) code, we analyzed some of the best eclipsing binaries we discovered. Our results show that these studied systems turn out to be ranging from detached to double-contact binaries, with low eccentricities and high inclinations of approximately 80°. Their surface temperatures range between 3500 K and 8000 K.

  16. Beyond MACS: A Snapshot Survey of the Most Massive Clusters of Galaxies at z>0.5

    Science.gov (United States)

    Ebeling, Harald

    2017-08-01

    Truly massive galaxy clusters play a pivotal role for a wealth of extragalactic and cosmological research topics, and SNAPshot observations of these systems are ideally suited to identify the most promising cluster targets for further, in-depth study. The power of this approach was demonstrated by ACS/WFC3 SNAPshots of X-ray selected MACS and eMACS clusters at z>0.3 obtained by us in previous Cycles (44 of them in all of F606W, F814W, F110W, and F140W). Based on these data, the CLASH MCT program selected 16 out of 25 of their targets to be MACS clusters. Similarly, all but one of the six most powerful cluster lenses selected for in-depth study by the HST Frontier Fields initiative are MACS detections, and so are 16 of the 29 z>0.3 clusters targeted by the RELICS legacy program.We propose to extend our spectacularly successful SNAPshot survey of the most X-ray luminous distant clusters to a redshift-mass regime that is poorly sampled by any other project. Targeting only extremely massive clusters at z>0.5 from the X-ray selected eMACS sample (median velocity dispersion: 1180 km/s), the proposed program will (a) identify the most powerful gravitational telescopes at yet higher redshift for the next generation of in-depth studies of the distant Universe with HST and JWST, (b) provide constraints on the mass distribution within these extreme systems, (c) help improve our understanding of the physical nature of galaxy-galaxy and galaxy-gas interactions in cluster cores, and (d) unveil Balmer Break Galaxies at z 2 and Lyman-break galaxies at z>6 as F814W dropouts.Acknowledging the broad community interest in our sample we waive our data rights for these observations.

  17. A VLA SURVEY FOR FAINT COMPACT RADIO SOURCES IN THE ORION NEBULA CLUSTER

    Energy Technology Data Exchange (ETDEWEB)

    Sheehan, Patrick D.; Eisner, Josh A. [Steward Observatory, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Mann, Rita K. [National Research Council Canada, 5071 West Saanich Road, Victoria, BC, V9E 2E7 (Canada); Williams, Jonathan P., E-mail: psheehan@email.arizona.edu [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

    2016-11-10

    We present Karl G. Jansky Very Large Array 1.3, 3.6, and 6 cm continuum maps of compact radio sources in the Orion Nebular Cluster (ONC). We mosaicked 34 arcmin{sup 2} at 1.3 cm, 70 arcmin{sup 2} at 3.6 cm and 109 arcmin{sup 2} at 6 cm, containing 778 near-infrared detected young stellar objects and 190 Hubble Space Telescope -identified proplyds (with significant overlap between those characterizations). We detected radio emission from 175 compact radio sources in the ONC, including 26 sources that were detected for the first time at these wavelengths. For each detected source, we fitted a simple free–free and dust emission model to characterize the radio emission. We extrapolate the free–free emission spectrum model for each source to ALMA bands to illustrate how these measurements could be used to correctly measure protoplanetary disk dust masses from submillimeter flux measurements. Finally, we compare the fluxes measured in this survey with previously measured fluxes for our targets, as well as four separate epochs of 1.3 cm data, to search for and quantify the variability of our sources.

  18. Clustering of High Redshift (z>2.9) Quasars from the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Yue; Strauss, Michael A.; Oguri, Masamune; Hennawi, Joseph F.; Fan, Xiaohui; Richards, Gordon T.; Hall, Patrick B.; Schneider, Donald P.; Szalay, Alexander S.; Thakar, Anirudda R.; Berk, Daniel E.Vanden; Anderson, Scott F.; Bahcall, Neta A.; /KIPAC, Menlo Park

    2006-11-30

    We study the two-point correlation function of a uniformly selected sample of 4,428 optically selected luminous quasars with redshift 2.9 {le} z {le} 5.4 selected over 4041 deg{sup 2} from the Fifth Data Release of the Sloan Digital Sky Survey. We fit a power-law to the projected correlation function w{sub p}(r{sub p}) to marginalize over redshift space distortions and redshift errors. For a real-space correlation function of the form {zeta}(r) = (r/r{sub 0}){sup -{gamma}}, the fitted parameters in comoving coordinates are r{sub 0} = 15.2 {+-} 2.7 h{sup -1} Mpc and {gamma} = 2.0 {+-} 0.3, over a scale range 4 {le} r{sub p} {le} 150 h{sup -1} Mpc. Thus high-redshift quasars are appreciably more strongly clustered than their z {approx} 1.5 counterparts, which have a comoving clustering length r{sub 0} {approx} 6.5 h{sup -1} Mpc. Dividing our sample into two redshift bins: 2.9 {le} z {le} 3.5 and z {ge} 3.5, and assuming a power-law index {gamma} = 2.0, we find a correlation length of r{sub 0} = 16.9 {+-} 1.7 h{sup -1} Mpc for the former, and r{sub 0} = 24.3 {+-} 2.4 h{sup -1} Mpc for the latter. Strong clustering at high redshift indicates that quasars are found in very massive, and therefore highly biased, halos. Following Martini & Weinberg, we relate the clustering strength and quasar number density to the quasar lifetimes and duty cycle. Using the Sheth & Tormen halo mass function, the quasar lifetime is estimated to lie in the range 4 {approx} 50 Myr for quasars with 2.9 {le} z {le} 3.5; and 30 {approx} 600 Myr for quasars with z {ge} 3.5. The corresponding duty cycles are 0.004 {approx} 0.05 for the lower redshift bin and 0.03 {approx} 0.6 for the higher redshift bin. The minimum mass of halos in which these quasars reside is 2-3 x 10{sup 12} h{sup -1} M{sub {circle_dot}} for quasars with 2.9 {le} z {le} 3.5 and 4-6 x 10{sup 12} h{sup -1} M{sub {circle_dot}} for quasars with z {ge} 3.5; the effective bias factor b{sub eff} increases with redshift, e.g., b

  19. A Measurement of the Rate of Type Ia Supernovae in Galaxy Clusters from the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Dilday, Benjamin; /Rutgers U., Piscataway /Chicago U. /KICP, Chicago; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Becker, Andrew; /Washington U., Seattle, Astron. Dept.; Bender, Ralf; /Munich, Tech. U. /Munich U. Observ.; Castander, Francisco; /Barcelona, IEEC; Cinabro, David; /Wayne State U.; Frieman, Joshua A.; /Chicago U. /Fermilab; Galbany, Lluis; /Barcelona, IFAE; Garnavich, Peter; /Notre Dame U.; Goobar, Ariel; /Stockholm U., OKC /Stockholm U.; Hopp, Ulrich; /Munich, Tech. U. /Munich U. Observ. /Tokyo U.

    2010-03-01

    We present measurements of the Type Ia supernova (SN) rate in galaxy clusters based on data from the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. The cluster SN Ia rate is determined from 9 SN events in a set of 71 C4 clusters at z {le} 0.17 and 27 SN events in 492 maxBCG clusters at 0.1 {le} z {le} 0.3. We find values for the cluster SN Ia rate of (0.37{sub -0.12-0.01}{sup +0.17+0.01}) SNur h{sup 2} and (0.55{sub -0.11-0.01}{sup +0.13+0.02}) SNur h{sup 2} (SNux = 10{sup -12}L{sub x{circle_dot}}{sup -1} yr{sup -1}) in C4 and maxBCG clusters, respectively, where the quoted errors are statistical and systematic, respectively. The SN rate for early-type galaxies is found to be (0.31{sub -0.12-0.01}{sup +0.18+0.01}) SNur h{sup 2} and (0.49{sub -0.11-0.01}{sup +0.15+0.02}) SNur h{sup 2} in C4 and maxBCG clusters, respectively. The SN rate for the brightest cluster galaxies (BCG) is found to be (2.04{sub -1.11-0.04}{sup +1.99+0.07}) SNur h{sup 2} and (0.36{sub -0.30-0.01}{sup +0.84+0.01}) SNur h{sup 2} in C4 and maxBCG clusters, respectively. The ratio of the SN Ia rate in cluster early-type galaxies to that of the SN Ia rate in field early-type galaxies is 1.94{sub -0.91-0.015}{sup +1.31+0.043} and 3.02{sub -1.03-0.048}{sup +1.31+0.062}, for C4 and maxBCG clusters, respectively. The SN rate in galaxy clusters as a function of redshift, which probes the late time SN Ia delay distribution, shows only weak dependence on redshift. Combining our current measurements with previous measurements, we fit the cluster SN Ia rate data to a linear function of redshift, and find r{sub L} = [(0.49{sub -0.14}{sup +0.15}) + (0.91{sub -0.81}{sup +0.85}) x z] SNuB h{sup 2}. A comparison of the radial distribution of SNe in cluster to field early-type galaxies shows possible evidence for an enhancement of the SN rate in the cores of cluster early-type galaxies. With an observation of at most 3 hostless, intra-cluster SNe Ia, we estimate the fraction of cluster SNe that are

  20. A MEASUREMENT OF THE RATE OF TYPE Ia SUPERNOVAE IN GALAXY CLUSTERS FROM THE SDSS-II SUPERNOVA SURVEY

    International Nuclear Information System (INIS)

    Dilday, Benjamin; Jha, Saurabh W.; Bassett, Bruce; Becker, Andrew; Bender, Ralf; Hopp, Ulrich; Castander, Francisco; Cinabro, David; Frieman, Joshua A.; Galbany, LluIs; Miquel, Ramon; Garnavich, Peter; Goobar, Ariel; Ihara, Yutaka; Kessler, Richard; Lampeitl, Hubert; Nichol, Robert C.; Marriner, John; Molla, Mercedes

    2010-01-01

    We present measurements of the Type Ia supernova (SN) rate in galaxy clusters based on data from the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. The cluster SN Ia rate is determined from 9 SN events in a set of 71 C4 clusters at z ≤ 0.17 and 27 SN events in 492 maxBCG clusters at 0.1 ≤ z ≤ 0.3. We find values for the cluster SN Ia rate of (0.37 +0.17+0.01 -0.12-0.01 ) SNur h 2 and (0.55 +0.13+0.02 -0.11-0.01 ) SNur h 2 (SNux = 10 -12 L -1 xsun yr -1 ) in C4 and maxBCG clusters, respectively, where the quoted errors are statistical and systematic, respectively. The SN rate for early-type galaxies is found to be (0.31 +0.18+0.01 -0.12-0.01 ) SNur h 2 and (0.49 +0.15+0.02 -0.11-0.01 ) SNur h 2 in C4 and maxBCG clusters, respectively. The SN rate for the brightest cluster galaxies (BCG) is found to be (2.04 +1.99+0.07 -1.11-0.04 ) SNur h 2 and (0.36 +0.84+0.01 -0.30-0.01 ) SNur h 2 in C4 and maxBCG clusters, respectively. The ratio of the SN Ia rate in cluster early-type galaxies to that of the SN Ia rate in field early-type galaxies is 1.94 +1.31+0.043 -0.91-0.015 and 3.02 +1.31+0.062 -1.03-0.048 , for C4 and maxBCG clusters, respectively. The SN rate in galaxy clusters as a function of redshift, which probes the late time SN Ia delay distribution, shows only weak dependence on redshift. Combining our current measurements with previous measurements, we fit the cluster SN Ia rate data to a linear function of redshift, and find r L = [(0.49 +0.15 -0.14 )+(0.91 +0.85 -0.81 ) x z] SNuB h 2 . A comparison of the radial distribution of SNe in cluster to field early-type galaxies shows possible evidence for an enhancement of the SN rate in the cores of cluster early-type galaxies. With an observation of at most three hostless, intra-cluster SNe Ia, we estimate the fraction of cluster SNe that are hostless to be (9.4 +8.3 -5.1 )%.

  1. PROSPECTS FOR MEASURING THE RELATIVE VELOCITIES OF GALAXY CLUSTERS IN PHOTOMETRIC SURVEYS USING THE KINETIC SUNYAEV-ZEL'DOVICH EFFECT

    International Nuclear Information System (INIS)

    Keisler, Ryan; Schmidt, Fabian

    2013-01-01

    We consider the prospects for measuring the pairwise kinetic Sunyaev-Zel'dovich (kSZ) signal from galaxy clusters discovered in large photometric surveys such as the Dark Energy Survey (DES). We project that the DES cluster sample will, in conjunction with existing mm-wave data from the South Pole Telescope (SPT), yield a detection of the pairwise kSZ signal at the 8σ-13σ level, with sensitivity peaking for clusters separated by ∼100 Mpc distances. A next-generation version of SPT would allow for a 18σ-30σ detection and would be limited by variance from the kSZ signal itself and the residual thermal Sunyaev-Zel'dovich (tSZ) signal. Throughout our analysis, we assume photometric redshift errors that wash out the signal for clusters separated by ∼<50 Mpc; a spectroscopic survey of the DES sample would recover this signal and allow for a 26σ-43σ detection, and would again be limited by kSZ/tSZ variance. Assuming a standard model of structure formation, these high-precision measurements of the pairwise kSZ signal will yield detailed information on the gas content of the galaxy clusters. Alternatively, if the gas can be sufficiently characterized by other means (e.g., using tSZ, X-ray, or weak lensing), then the relative velocities of the galaxy clusters can be isolated, thereby providing a precision measurement of gravity on 100 Mpc scales. We briefly consider the utility of these measurements for constraining theories of modified gravity.

  2. THE NEXT GENERATION VIRGO CLUSTER SURVEY. VI. THE KINEMATICS OF ULTRA-COMPACT DWARFS AND GLOBULAR CLUSTERS IN M87

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hong-Xin; Peng, Eric W.; Li, Biao [Department of Astronomy, Peking University, Beijing 100871 (China); Côté, Patrick; Ferrarese, Laura; Gwyn, Stephen D. J.; Blakeslee, John P. [National Research Council of Canada, Herzberg Astronomy and Astrophysics Program, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Liu, Chengze [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Cuillandre, Jean-Charles [Canada-France-Hawaii Telescope Corporation, Kamuela, HI 96743 (United States); Caldwell, Nelson [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Jordán, Andrés; Muñoz, Roberto P.; Puzia, Thomas H. [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 7820436 Macul, Santiago (Chile); Lançon, Ariane [Observatoire astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l' Universite, F-67000 Strasbourg (France); Bekki, Kenji [School of Physics, University of New South Wales, Sydney 2052, NSW (Australia); Boselli, Alessandro [Aix Marseille Université, CNRS, LAM (Laboratoire d' Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France); Drinkwater, Michael J. [School of Mathematics and Physics, University of Queensland, Brisbane, QLD 4072 (Australia); Duc, Pierre-Alain, E-mail: hongxin@pku.edu.cn, E-mail: peng@pku.edu.cn [Laboratoire AIM Paris-Saclay, CNRS/INSU, Université Paris Diderot, CEA/IRFU/SAp, F-91191 Gif-sur-Yvette Cedex (France); and others

    2015-03-20

    The origin of ultra-compact dwarfs (UCDs; r{sub h} ≳ 10 pc)—objects larger and more massive than typical globular clusters (GCs), but more compact than typical dwarf galaxies—has been hotly debated in the 15 years since their discovery. Even whether UCDs should be considered galactic in origin, or simply the most extreme star clusters, is not yet settled. We present the dynamical properties of 97 spectroscopically confirmed UCDs and 911 GCs associated with the central cD galaxy of the Virgo cluster, M87. Our UCDs, of which 89% have M {sub *} ≳ 2× 10{sup 6} M {sub ☉} and 92% are as blue as the classic blue GCs, nearly triple the confirmed sample of Virgo UCDs, providing by far the best opportunity for studying global dynamics of a UCD system. We found that (1) UCDs have a surface number density profile that is shallower than that of blue GCs in the inner ∼70 kpc and as steep as that of red GCs at larger radii; (2) UCDs exhibit a significantly stronger rotation than GCs, and blue GCs seem to have a velocity field that is more consistent with that of the surrounding dwarf ellipticals than with that of UCDs; (3) UCDs have an orbital anisotropy profile that is tangentially biased at radii ≲40 kpc and radially biased farther out, whereas blue GCs become more tangentially biased at larger radii beyond ∼40 kpc; (4) GCs with M {sub *} ≳ 2 × 10{sup 6} M {sub ☉} have rotational properties indistinguishable from the less massive ones, suggesting that it is the size, instead of mass, that differentiates UCDs from GCs as kinematically distinct populations. We conclude that most UCDs in M87 are not consistent with being merely the most luminous and extended examples of otherwise normal GCs. The radially biased orbital structure of UCDs at large radii is in general agreement with the 'tidally threshed dwarf galaxy' scenario.

  3. THE NEXT GENERATION VIRGO CLUSTER SURVEY. VI. THE KINEMATICS OF ULTRA-COMPACT DWARFS AND GLOBULAR CLUSTERS IN M87

    International Nuclear Information System (INIS)

    Zhang, Hong-Xin; Peng, Eric W.; Li, Biao; Côté, Patrick; Ferrarese, Laura; Gwyn, Stephen D. J.; Blakeslee, John P.; Liu, Chengze; Cuillandre, Jean-Charles; Caldwell, Nelson; Jordán, Andrés; Muñoz, Roberto P.; Puzia, Thomas H.; Lançon, Ariane; Bekki, Kenji; Boselli, Alessandro; Drinkwater, Michael J.; Duc, Pierre-Alain

    2015-01-01

    The origin of ultra-compact dwarfs (UCDs; r h ≳ 10 pc)—objects larger and more massive than typical globular clusters (GCs), but more compact than typical dwarf galaxies—has been hotly debated in the 15 years since their discovery. Even whether UCDs should be considered galactic in origin, or simply the most extreme star clusters, is not yet settled. We present the dynamical properties of 97 spectroscopically confirmed UCDs and 911 GCs associated with the central cD galaxy of the Virgo cluster, M87. Our UCDs, of which 89% have M *  ≳ 2× 10 6 M ☉ and 92% are as blue as the classic blue GCs, nearly triple the confirmed sample of Virgo UCDs, providing by far the best opportunity for studying global dynamics of a UCD system. We found that (1) UCDs have a surface number density profile that is shallower than that of blue GCs in the inner ∼70 kpc and as steep as that of red GCs at larger radii; (2) UCDs exhibit a significantly stronger rotation than GCs, and blue GCs seem to have a velocity field that is more consistent with that of the surrounding dwarf ellipticals than with that of UCDs; (3) UCDs have an orbital anisotropy profile that is tangentially biased at radii ≲40 kpc and radially biased farther out, whereas blue GCs become more tangentially biased at larger radii beyond ∼40 kpc; (4) GCs with M *  ≳ 2 × 10 6 M ☉ have rotational properties indistinguishable from the less massive ones, suggesting that it is the size, instead of mass, that differentiates UCDs from GCs as kinematically distinct populations. We conclude that most UCDs in M87 are not consistent with being merely the most luminous and extended examples of otherwise normal GCs. The radially biased orbital structure of UCDs at large radii is in general agreement with the 'tidally threshed dwarf galaxy' scenario

  4. THE NEXT GENERATION VIRGO CLUSTER SURVEY XVI: THE ANGULAR MOMENTUM OF DWARF EARLY-TYPE GALAXIES FROM GLOBULAR CLUSTER SATELLITES

    Energy Technology Data Exchange (ETDEWEB)

    Toloba, Elisa; Guhathakurta, Puragra [UCO/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Li, Biao; Peng, Eric W.; Zhang, Hongxin [Department of Astronomy, Peking University, Beijing 100871 (China); Ferrarese, Laura; Côté, Patrick; Gwyn, Stephen [National Research Council of Canada, Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Emsellem, Eric [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748, Garching (Germany); Boselli, Alessandro [Laboratoire d’Astrophysique de Marseille-LAM, Université d’Aix-Marseille and CNRS, UMR 7326, 38 rue F. Joliot-Curie, F-13388 Marseille Cedex 13 (France); Cuillandre, Jean-Charles [CEA/IRFU/SAP, Laboratoire AIM Paris-Saclay, CNRS/INSU, Université Paris Diderot, Observatoire de Paris, PSL Research University, F-91191 Gif-sur-Yvette Cedex (France); Jordan, Andres [Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Vicuna Mackenna 4860, 7820436 Macul, Santiago (Chile); Liu, Chengze, E-mail: toloba@ucolick.org [Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2016-05-01

    We analyze the kinematics of six Virgo cluster dwarf early-type galaxies (dEs) from their globular cluster (GC) systems. We present new Keck/DEIMOS spectroscopy for three of them and re-analyze the data found in the literature for the remaining three. We use two independent methods to estimate the rotation amplitude ( V {sub rot}) and velocity dispersion ( σ {sub GC}) of the GC systems and evaluate their statistical significance by simulating non-rotating GC systems with the same number of GC satellites and velocity uncertainties. Our measured kinematics agree with the published values for the three galaxies from the literature and, in all cases, some rotation is measured. However, our simulations show that the null hypothesis of being non-rotating GC systems cannot be ruled out. In the case of VCC 1861, the measured V {sub rot} and the simulations indicate that it is not rotating. In the case of VCC 1528, the null hypothesis can be marginally ruled out, and thus it might be rotating although further confirmation is needed. In our analysis, we find that, in general, the measured V {sub rot} tends to be overestimated and the measured σ {sub GC} tends to be underestimated by amounts that depend on the intrinsic V {sub rot}/ σ {sub GC}, the number of observed GCs ( N {sub GC}), and the velocity uncertainties. The bias is negligible when N {sub GC} ≳ 20. In those cases where a large N {sub GC} is not available, it is imperative to obtain data with small velocity uncertainties. For instance, errors of ≤2 km s{sup −1} lead to V {sub rot} < 10 km s{sup −1} for a system that is intrinsically not rotating.

  5. Energy Efficient Hierarchical Clustering Approaches in Wireless Sensor Networks: A Survey

    Directory of Open Access Journals (Sweden)

    Bilal Jan

    2017-01-01

    Full Text Available Wireless sensor networks (WSN are one of the significant technologies due to their diverse applications such as health care monitoring, smart phones, military, disaster management, and other surveillance systems. Sensor nodes are usually deployed in large number that work independently in unattended harsh environments. Due to constraint resources, typically the scarce battery power, these wireless nodes are grouped into clusters for energy efficient communication. In clustering hierarchical schemes have achieved great interest for minimizing energy consumption. Hierarchical schemes are generally categorized as cluster-based and grid-based approaches. In cluster-based approaches, nodes are grouped into clusters, where a resourceful sensor node is nominated as a cluster head (CH while in grid-based approach the network is divided into confined virtual grids usually performed by the base station. This paper highlights and discusses the design challenges for cluster-based schemes, the important cluster formation parameters, and classification of hierarchical clustering protocols. Moreover, existing cluster-based and grid-based techniques are evaluated by considering certain parameters to help users in selecting appropriate technique. Furthermore, a detailed summary of these protocols is presented with their advantages, disadvantages, and applicability in particular cases.

  6. Massive open star clusters using the VVV survey. I. Presentation of the data and description of the approach

    Science.gov (United States)

    Chené, A.-N.; Borissova, J.; Clarke, J. R. A.; Bonatto, C.; Majaess, D. J.; Moni Bidin, C.; Sale, S. E.; Mauro, F.; Kurtev, R.; Baume, G.; Feinstein, C.; Ivanov, V. D.; Geisler, D.; Catelan, M.; Minniti, D.; Lucas, P.; de Grijs, R.; Kumar, M. S. N.

    2012-09-01

    Context. The ESO Public Survey "VISTA Variables in the Vía Láctea" (VVV) provides deep multi-epoch infrared observations for unprecedented 562 sq. degrees of the Galactic bulge, and adjacent regions of the disk. Aims: The VVV observations will foster the construction of a sample of Galactic star clusters with reliable and homogeneously derived physical parameters (e.g., age, distance, and mass, etc.). In this first paper in a series, the methodology employed to establish cluster parameters for the envisioned database are elaborated upon by analysing four known young open clusters: Danks 1, Danks 2, RCW 79, and DBS 132. The analysis offers a first glimpse of the information that can be gleaned from the VVV observations for clusters in the final database. Methods: Wide-field, deep JHKs VVV observations, combined with new infrared spectroscopy, are employed to constrain fundamental parameters for a subset of clusters. Results: Results are inferred from VVV near-infrared photometry and numerous low resolution spectra (typically more than 10 per cluster). The high quality of the spectra and the deep wide-field VVV photometry enables us to precisely and independently determine the characteristics of the clusters studied, which we compare to previous determinations. An anomalous reddening law in the direction of the Danks clusters is found, specifically E(J - H)/E(H - Ks) = 2.20 ± 0.06, which exceeds published values for the inner Galaxy. The G305 star forming complex, which includes the Danks clusters, lies beyond the Sagittarius-Carina spiral arm and occupies the Centaurus arm. Finally, the first deep infrared colour-magnitude diagram of RCW 79 is presented, which reveals a sizeable pre-main sequence population. A list of candidate variable stars in G305 region is reported. Conclusions: This study demonstrates the strength of the dataset and methodology employed, and constitutes the first step of a broader study which shall include reliable parameters for a sizeable

  7. Innovation in Industrial Clusters: a Survey of Footwear Companies in Brazil

    OpenAIRE

    Hélcio Martins Tristão; Pedro Carlos Oprime; Daniel Jugend; Sérgio Luis da Silva

    2013-01-01

    The aim of this study is to characterize the relationships in innovation and business clustering processes in the productive chain of small and medium enterprises (SME) of Brazil. The object of study are SMEs the local procuctive cluster of the shoes in Franca, State of São Paulo. The conceptual model developed is based on the following constructs: vertical integration, innovation and characteristics of the cluster, and it is focused on identifying the agents that act predominantly in product...

  8. AUTOMATED UNSUPERVISED CLASSIFICATION OF THE SLOAN DIGITAL SKY SURVEY STELLAR SPECTRA USING k-MEANS CLUSTERING

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Almeida, J.; Allende Prieto, C., E-mail: jos@iac.es, E-mail: callende@iac.es [Instituto de Astrofisica de Canarias, E-38205 La Laguna, Tenerife (Spain)

    2013-01-20

    Large spectroscopic surveys require automated methods of analysis. This paper explores the use of k-means clustering as a tool for automated unsupervised classification of massive stellar spectral catalogs. The classification criteria are defined by the data and the algorithm, with no prior physical framework. We work with a representative set of stellar spectra associated with the Sloan Digital Sky Survey (SDSS) SEGUE and SEGUE-2 programs, which consists of 173,390 spectra from 3800 to 9200 A sampled on 3849 wavelengths. We classify the original spectra as well as the spectra with the continuum removed. The second set only contains spectral lines, and it is less dependent on uncertainties of the flux calibration. The classification of the spectra with continuum renders 16 major classes. Roughly speaking, stars are split according to their colors, with enough finesse to distinguish dwarfs from giants of the same effective temperature, but with difficulties to separate stars with different metallicities. There are classes corresponding to particular MK types, intrinsically blue stars, dust-reddened, stellar systems, and also classes collecting faulty spectra. Overall, there is no one-to-one correspondence between the classes we derive and the MK types. The classification of spectra without continuum renders 13 classes, the color separation is not so sharp, but it distinguishes stars of the same effective temperature and different metallicities. Some classes thus obtained present a fairly small range of physical parameters (200 K in effective temperature, 0.25 dex in surface gravity, and 0.35 dex in metallicity), so that the classification can be used to estimate the main physical parameters of some stars at a minimum computational cost. We also analyze the outliers of the classification. Most of them turn out to be failures of the reduction pipeline, but there are also high redshift QSOs, multiple stellar systems, dust-reddened stars, galaxies, and, finally, odd

  9. An ALMA Survey of Protoplanetary Disks in the σ Orionis Cluster

    Energy Technology Data Exchange (ETDEWEB)

    Ansdell, M.; Williams, J. P.; Marel, N. van der [Institute for Astronomy, University of Hawai‘i at Mānoa, Honolulu, HI (United States); Manara, C. F. [Scientific Support Office, Directorate of Science, European Space Research and Technology Centre (ESA/ESTEC), Keplerlaan 1, 2201 AZ Noordwijk (Netherlands); Miotello, A.; Dishoeck, E. F. van [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Facchini, S. [Max-Plank-Institut für Extraterrestrische Physik, Giessenbachstraße 1, D-85748 Garching (Germany); Testi, L. [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy)

    2017-05-01

    The σ  Orionis cluster is important for studying protoplanetary disk evolution, as its intermediate age (∼3–5 Myr) is comparable to the median disk lifetime. We use ALMA to conduct a high-sensitivity survey of dust and gas in 92 protoplanetary disks around σ  Orionis members with M {sub *} ≳ 0.1  M {sub ⊙}. Our observations cover the 1.33 mm continuum and several CO J  = 2–1 lines: out of 92 sources, we detect 37 in the millimeter continuum and 6 in {sup 12}CO, 3 in {sup 13}CO, and none in C{sup 18}O. Using the continuum emission to estimate dust mass, we find only 11 disks with M {sub dust} ≳ 10  M {sub ⊕}, indicating that after only a few Myr of evolution most disks lack sufficient dust to form giant planet cores. Stacking the individually undetected continuum sources limits their average dust mass to 5×  lower than that of the faintest detected disk, supporting theoretical models that indicate rapid dissipation once disk clearing begins. Comparing the protoplanetary disk population in σ  Orionis to those of other star-forming regions supports the steady decline in average dust mass and the steepening of the M {sub dust}– M {sub *} relation with age; studying these evolutionary trends can inform the relative importance of different disk processes during key eras of planet formation. External photoevaporation from the central O9 star is influencing disk evolution throughout the region: dust masses clearly decline with decreasing separation from the photoionizing source, and the handful of CO detections exist at projected separations of >1.5 pc. Collectively, our findings indicate that giant planet formation is inherently rare and/or well underway by a few Myr of age.

  10. Cluster survey of the high-altitude cusp properties: a three-year statistical study

    Directory of Open Access Journals (Sweden)

    B. Lavraud

    2004-09-01

    Full Text Available The global characteristics of the high-altitude cusp and its surrounding regions are investigated using a three-year statistical survey based on data obtained by the Cluster spacecraft. The analysis involves an elaborate orbit-sampling methodology that uses a model field and takes into account the actual solar wind conditions and level of geomagnetic activity. The spatial distribution of the magnetic field and various plasma parameters in the vicinity of the low magnetic field exterior cusp are determined and it is found that: 1 The magnetic field distribution shows the presence of an intermediate region between the magnetosheath and the magnetosphere: the exterior cusp, 2 This region is characterized by the presence of dense plasma of magnetosheath origin; a comparison with the Tsyganenko (1996 magnetic field model shows that it is diamagnetic in nature, 3 The spatial distributions show that three distinct boundaries with the lobes, the dayside plasma sheet and the magnetosheath surround the exterior cusp, 4 The external boundary with the magnetosheath has a sharp bulk velocity gradient, as well as a density decrease and temperature increase as one goes from the magnetosheath to the exterior cusp, 5 While the two inner boundaries form a funnel, the external boundary shows no clear indentation, 6 The plasma and magnetic pressure distributions suggest that the exterior cusp is in equilibrium with its surroundings in a statistical sense, and 7 A preliminary analysis of the bulk flow distributions suggests that the exterior cusp is stagnant under northward IMF conditions but convective under southward IMF conditions.

  11. Subaru Weak-Lensing Survey II: Multi-Object Spectroscopy and Cluster Masses

    Science.gov (United States)

    Hamana, Takashi; Miyazaki, Satoshi; Kashikawa, Nobunari; Ellis, Richard S.; Massey, Richard J.; Refregier, Alexandre; Taylor, James E.

    2009-08-01

    We present the first results of a multi-object spectroscopic campaign to follow up cluster candidates located via weak lensing. Our main goals are to search for spatial concentrations of galaxies that are plausible optical counterparts of the weak-lensing signals, and to determine the cluster redshifts from those of member galaxies. Around each of 36 targeted cluster candidates, we obtained 15-32 galaxy redshifts. For 28 of these targets, we confirmed a secure cluster identification, with more than five spectroscopic galaxies within a velocity of ±3000km s-1. This includes three cases where two clusters at different redshifts are projected along the same line-of-sight. In 6 of the 8 unconfirmed targets, we found multiple small galaxy concentrations at different redshifts, each containing at least three spectroscopic galaxies. The weak-lensing signal around those systems was thus probably created by the projection of groups or small clusters along the same line-of-sight. In both of the remaining two targets, a single small galaxy concentration was found. In some candidate super-cluster systems, we found additional evidence of filaments connecting the main density peak to an additional nearby structure. For a subsample of our most cleanly measured clusters, we investigated the statistical relation between their weak-lensing mass (MNFW, σSIS) and the velocity dispersion of their member galaxies (σv), comparing our sample with optically and X-ray selected samples from the literature. Our lensing-selected clusters are consistent with σv = σSIS, with a similar scatter to that of optically and X-ray selected clusters. We also derived an empirical relation between the cluster mass and the galaxy velocity dispersion, M200E(z) = 11.0 × 1014 × (σv/1000km s-1)3.0 h-1 Modot, which is in reasonable agreement with predictions of N-body simulations in the Λ CDM cosmology.

  12. A Survey on the Taxonomy of Cluster-Based Routing Protocols for Homogeneous Wireless Sensor Networks

    Science.gov (United States)

    Naeimi, Soroush; Ghafghazi, Hamidreza; Chow, Chee-Onn; Ishii, Hiroshi

    2012-01-01

    The past few years have witnessed increased interest among researchers in cluster-based protocols for homogeneous networks because of their better scalability and higher energy efficiency than other routing protocols. Given the limited capabilities of sensor nodes in terms of energy resources, processing and communication range, the cluster-based protocols should be compatible with these constraints in either the setup state or steady data transmission state. With focus on these constraints, we classify routing protocols according to their objectives and methods towards addressing the shortcomings of clustering process on each stage of cluster head selection, cluster formation, data aggregation and data communication. We summarize the techniques and methods used in these categories, while the weakness and strength of each protocol is pointed out in details. Furthermore, taxonomy of the protocols in each phase is given to provide a deeper understanding of current clustering approaches. Ultimately based on the existing research, a summary of the issues and solutions of the attributes and characteristics of clustering approaches and some open research areas in cluster-based routing protocols that can be further pursued are provided. PMID:22969350

  13. Subaru weak-lensing survey of dark matter subhalos in the Coma cluster: Subhalo mass function and statistical properties

    International Nuclear Information System (INIS)

    Okabe, Nobuhiro; Futamase, Toshifumi; Kuroshima, Risa; Kajisawa, Masaru

    2014-01-01

    We present a 4 deg 2 weak gravitational lensing survey of subhalos in the very nearby Coma cluster using the Subaru/Suprime-Cam. The large apparent size of cluster subhalos allows us to measure the mass of 32 subhalos detected in a model-independent manner, down to the order of 10 –3 of the virial mass of the cluster. Weak-lensing mass measurements of these shear-selected subhalos enable us to investigate subhalo properties and the correlation between subhalo masses and galaxy luminosities for the first time. The mean distortion profiles stacked over subhalos show a sharply truncated feature which is well-fitted by a Navarro-Frenk-White (NFW) mass model with the truncation radius, as expected due to tidal destruction by the main cluster. We also found that subhalo masses, truncation radii, and mass-to-light ratios decrease toward the cluster center. The subhalo mass function, dn/dln M sub , in the range of 2 orders of magnitude in mass, is well described by a single power law or a Schechter function. Best-fit power indices of 1.09 −0.32 +0.42 for the former model and 0.99 −0.23 +0.34 for the latter, are in remarkable agreement with slopes of ∼0.9-1.0 predicted by the cold dark matter paradigm. The tangential distortion signals in the radial range of 0.02-2 h –1 Mpc from the cluster center show a complex structure which is well described by a composition of three mass components of subhalos, the NFW mass distribution as a smooth component of the main cluster, and a lensing model from a large scale structure behind the cluster. Although the lensing signals are 1 order of magnitude lower than those for clusters at z ∼ 0.2, the total signal-to-noise ratio, S/N = 13.3, is comparable, or higher, because the enormous number of background source galaxies compensates for the low lensing efficiency of the nearby cluster.

  14. Subaru Weak-lensing Survey of Dark Matter Subhalos in the Coma Cluster: Subhalo Mass Function and Statistical Properties

    Science.gov (United States)

    Okabe, Nobuhiro; Futamase, Toshifumi; Kajisawa, Masaru; Kuroshima, Risa

    2014-04-01

    We present a 4 deg2 weak gravitational lensing survey of subhalos in the very nearby Coma cluster using the Subaru/Suprime-Cam. The large apparent size of cluster subhalos allows us to measure the mass of 32 subhalos detected in a model-independent manner, down to the order of 10-3 of the virial mass of the cluster. Weak-lensing mass measurements of these shear-selected subhalos enable us to investigate subhalo properties and the correlation between subhalo masses and galaxy luminosities for the first time. The mean distortion profiles stacked over subhalos show a sharply truncated feature which is well-fitted by a Navarro-Frenk-White (NFW) mass model with the truncation radius, as expected due to tidal destruction by the main cluster. We also found that subhalo masses, truncation radii, and mass-to-light ratios decrease toward the cluster center. The subhalo mass function, dn/dln M sub, in the range of 2 orders of magnitude in mass, is well described by a single power law or a Schechter function. Best-fit power indices of 1.09^{+0.42}_{-0.32} for the former model and 0.99_{-0.23}^{+0.34} for the latter, are in remarkable agreement with slopes of ~0.9-1.0 predicted by the cold dark matter paradigm. The tangential distortion signals in the radial range of 0.02-2 h -1 Mpc from the cluster center show a complex structure which is well described by a composition of three mass components of subhalos, the NFW mass distribution as a smooth component of the main cluster, and a lensing model from a large scale structure behind the cluster. Although the lensing signals are 1 order of magnitude lower than those for clusters at z ~ 0.2, the total signal-to-noise ratio, S/N = 13.3, is comparable, or higher, because the enormous number of background source galaxies compensates for the low lensing efficiency of the nearby cluster. Based on data collected from the Subaru Telescope and obtained from SMOKA, operated by the Astronomy Data Center, National Astronomical Observatory of

  15. Title IX: With New Opportunities, Girls' Interest Rises

    Science.gov (United States)

    Toporek, Bryan

    2012-01-01

    On June 23, 1972, President Richard M. Nixon signed into law Title IX of the Education Amendments of 1972, which prohibits gender discrimination in any federally financed education program or activity. Title IX is far-reaching, but the law is most often associated with school and college athletics. Title IX allows schools to prove their athletic…

  16. 77 FR 64401 - Order of Succession for HUD Region IX

    Science.gov (United States)

    2012-10-19

    ... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT [FR-5550-D-12] Order of Succession for HUD Region IX... Field Offices (Region IX). This Order of Succession supersedes all previous Orders of Succession for HUD Region IX. DATES: Effective Date: October 9, 2012. FOR FURTHER INFORMATION CONTACT: Lawrence D. Reynolds...

  17. Next Generation Virgo Survey Photometry and Keck/DEIMOS Spectroscopy of Globular Cluster Satellites of Dwarf Elliptical Galaxies in the Virgo Cluster

    Science.gov (United States)

    Guhathakurta, Puragra; Toloba, Elisa; Peng, Eric W.; Li, Biao; Gwyn, Stephen; Ferrarese, Laura; Cote, Patrick; Chu, Jason; Sparkman, Lea; Chen, Stephanie; Yagati, Samyukta; Muller, Meredith; Next Generation Virgo Survey Collaboration

    2015-01-01

    We present results from an ongoing study of globular cluster (GC) satellites of low-luminosity dwarf elliptical (dE) galaxies in the Virgo cluster. Our 21 dE targets and candidate GC satellites around them in the apparent magnitude range g ~ 20-24 were selected from the Next Generation Virgo Survey (NGVS) and followed up with medium-resolution Keck/DEIMOS spectroscopy (resolving power: R ~ 2000; wavelength coverage: 4800-9500 Angstrom). In addition, the remaining space available on the nine DEIMOS multi-slit masks were populated with "filler" targets in the form of distant Milky Way halo star candidates in a comparable apparent magnitude range. A combination of radial velocity information (measured from the Keck/DEIMOS spectra), color-color information (from four-band NGVS photometry), and sky position information was used to sort the sample into the following categories: (1) GC satellites of dEs, (2) other non-satellite GCs in the Virgo cluster (we dub them "orphan" GCs), (3) foreground Milky Way stars that are members of the Sagittarius stream, the Virgo overdensity, or the field halo population, and (4) distant background galaxies. We stack the GC satellite population across all 21 host dEs and carry out dynamical modeling of the stacked sample in order to constrain the average mass of dark matter halos that these dEs are embedded in. We study rotation in the system of GC satellites of dEs in the handful of more populated systems in our sample - i.e., those that contain 10 or more GC satellites per dE. A companion AAS poster presented at this meeting (Chu, J. et al. 2015) presents chemical composition and age constraints for these GC satellites relative to the nuclei of the host dEs based on absorption line strengths in co-added spectra. The orphan GCs are likely to be intergalactic GCs within the Virgo cluster (or, equivalently, GCs in the remote outer envelope of the cluster's central galaxy, the giant elliptical M87).This project is funded in part by the

  18. THE CLUSTERING OF GALAXIES IN THE SDSS-III BARYON OSCILLATION SPECTROSCOPIC SURVEY: LUMINOSITY AND COLOR DEPENDENCE AND REDSHIFT EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Guo Hong; Zehavi, Idit [Department of Astronomy, Case Western Reserve University, OH 44106 (United States); Zheng Zheng [Department of Physics and Astronomy, University of Utah, UT 84112 (United States); Weinberg, David H. [Department of Astronomy and CCAPP, Ohio State University, Columbus, OH 43210 (United States); Berlind, Andreas A. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Blanton, Michael [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States); Chen Yanmei [Department of Astronomy, Nanjing University, Nanjing 210093 (China); Eisenstein, Daniel J.; McBride, Cameron K. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Ho, Shirley; Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Kazin, Eyal [Center for Astrophysics and Supercomputing, Swinburne University of Technology, P.O. Box 218, Hawthorn, Victoria 3122 (Australia); Manera, Marc; Maraston, Claudia; Percival, Will J.; Ross, Ashley J.; Samushia, Lado [Institute of Cosmology and Gravitation, Dennis Sciama Building, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom); Nuza, Sebastian E. [Leibniz-Institut fuer Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany); Padmanabhan, Nikhil; Parejko, John K. [Department of Physics, Yale University, 260 Whitney Ave, New Haven, CT 06520 (United States); and others

    2013-04-20

    We measure the luminosity and color dependence and the redshift evolution of galaxy clustering in the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Ninth Data Release. We focus on the projected two-point correlation function (2PCF) of subsets of its CMASS sample, which includes about 260,000 galaxies over {approx}3300 deg{sup 2} in the redshift range 0.43 < z < 0.7. To minimize the selection effect on galaxy clustering, we construct well-defined luminosity and color subsamples by carefully accounting for the CMASS galaxy selection cuts. The 2PCF of the whole CMASS sample, if approximated by a power-law, has a correlation length of r{sub 0} = 7.93 {+-} 0.06 h {sup -1} Mpc and an index of {gamma} = 1.85 {+-} 0.01. Clear dependences on galaxy luminosity and color are found for the projected 2PCF in all redshift bins, with more luminous and redder galaxies generally exhibiting stronger clustering and steeper 2PCF. The color dependence is also clearly seen for galaxies within the red sequence, consistent with the behavior of SDSS-II main sample galaxies at lower redshifts. At a given luminosity (k + e corrected), no significant evolution of the projected 2PCFs with redshift is detected for red sequence galaxies. We also construct galaxy samples of fixed number density at different redshifts, using redshift-dependent magnitude thresholds. The clustering of these galaxies in the CMASS redshift range is found to be consistent with that predicted by passive evolution. Our measurements of the luminosity and color dependence and redshift evolution of galaxy clustering will allow for detailed modeling of the relation between galaxies and dark matter halos and new constraints on galaxy formation and evolution.

  19. Providing Transparency to the Title IX Process

    Science.gov (United States)

    Hartle, Terry

    2017-01-01

    When U.S. Secretary of Education Betsy DeVos announced Sept. 7, 2017, that her department would revisit how Title IX rules are enforced with respect to campus sexual assault, she said the first step would be a "transparent notice and comment process" to replace the 2011 "guidance" (and follow up 2014 guidance) that has been…

  20. Platelet Glycoprotein Ib-IX and Malignancy

    Science.gov (United States)

    2010-09-01

    provide a unique microenvironment supporting the accumulation of more platelets and the elaboration of a fibrin - rich network produced by coagulation...process and can initiate the formation of a platelet - rich thrombus by tethering the platelet to a thrombogenic surface. Several ligands binding to GP Ib... Platelet Glycoprotein Ib-IX and Malignancy PRINCIPAL INVESTIGATOR: Jerry Ware, Ph.D

  1. Dark Energy Survey Year 1 Results: Cosmological Constraints from Galaxy Clustering and Weak Lensing

    Energy Technology Data Exchange (ETDEWEB)

    Abbott, T.M.C.; et al.

    2017-08-04

    We present cosmological results from a combined analysis of galaxy clustering and weak gravitational lensing, using 1321 deg$^2$ of $griz$ imaging data from the first year of the Dark Energy Survey (DES Y1). We combine three two-point functions: (i) the cosmic shear correlation function of 26 million source galaxies in four redshift bins, (ii) the galaxy angular autocorrelation function of 650,000 luminous red galaxies in five redshift bins, and (iii) the galaxy-shear cross-correlation of luminous red galaxy positions and source galaxy shears. To demonstrate the robustness of these results, we use independent pairs of galaxy shape, photometric redshift estimation and validation, and likelihood analysis pipelines. To prevent confirmation bias, the bulk of the analysis was carried out while blind to the true results; we describe an extensive suite of systematics checks performed and passed during this blinded phase. The data are modeled in flat $\\Lambda$CDM and $w$CDM cosmologies, marginalizing over 20 nuisance parameters, varying 6 (for $\\Lambda$CDM) or 7 (for $w$CDM) cosmological parameters including the neutrino mass density and including the 457 $\\times$ 457 element analytic covariance matrix. We find consistent cosmological results from these three two-point functions, and from their combination obtain $S_8 \\equiv \\sigma_8 (\\Omega_m/0.3)^{0.5} = 0.783^{+0.021}_{-0.025}$ and $\\Omega_m = 0.264^{+0.032}_{-0.019}$ for $\\Lambda$CDM for $w$CDM, we find $S_8 = 0.794^{+0.029}_{-0.027}$, $\\Omega_m = 0.279^{+0.043}_{-0.022}$, and $w=-0.80^{+0.20}_{-0.22}$ at 68% CL. The precision of these DES Y1 results rivals that from the Planck cosmic microwave background measurements, allowing a comparison of structure in the very early and late Universe on equal terms. Although the DES Y1 best-fit values for $S_8$ and $\\Omega_m$ are lower than the central values from Planck ...

  2. The Herschel Virgo Cluster Survey. XVII. SPIRE point-source catalogs and number counts

    Science.gov (United States)

    Pappalardo, Ciro; Bendo, George J.; Bianchi, Simone; Hunt, Leslie; Zibetti, Stefano; Corbelli, Edvige; di Serego Alighieri, Sperello; Grossi, Marco; Davies, Jonathan; Baes, Maarten; De Looze, Ilse; Fritz, Jacopo; Pohlen, Michael; Smith, Matthew W. L.; Verstappen, Joris; Boquien, Médéric; Boselli, Alessandro; Cortese, Luca; Hughes, Thomas; Viaene, Sebastien; Bizzocchi, Luca; Clemens, Marcel

    2015-01-01

    Aims: We present three independent catalogs of point-sources extracted from SPIRE images at 250, 350, and 500 μm, acquired with the Herschel Space Observatory as a part of the Herschel Virgo Cluster Survey (HeViCS). The catalogs have been cross-correlated to consistently extract the photometry at SPIRE wavelengths for each object. Methods: Sources have been detected using an iterative loop. The source positions are determined by estimating the likelihood to be a real source for each peak on the maps, according to the criterion defined in the sourceExtractorSussextractor task. The flux densities are estimated using the sourceExtractorTimeline, a timeline-based point source fitter that also determines the fitting procedure with the width of the Gaussian that best reproduces the source considered. Afterwards, each source is subtracted from the maps, removing a Gaussian function in every position with the full width half maximum equal to that estimated in sourceExtractorTimeline. This procedure improves the robustness of our algorithm in terms of source identification. We calculate the completeness and the flux accuracy by injecting artificial sources in the timeline and estimate the reliability of the catalog using a permutation method. Results: The HeViCS catalogs contain about 52 000, 42 200, and 18 700 sources selected at 250, 350, and 500 μm above 3σ and are ~75%, 62%, and 50% complete at flux densities of 20 mJy at 250, 350, 500 μm, respectively. We then measured source number counts at 250, 350, and 500 μm and compare them with previous data and semi-analytical models. We also cross-correlated the catalogs with the Sloan Digital Sky Survey to investigate the redshift distribution of the nearby sources. From this cross-correlation, we select ~2000 sources with reliable fluxes and a high signal-to-noise ratio, finding an average redshift z ~ 0.3 ± 0.22 and 0.25 (16-84 percentile). Conclusions: The number counts at 250, 350, and 500 μm show an increase in

  3. EXPLORING ANTICORRELATIONS AND LIGHT ELEMENT VARIATIONS IN NORTHERN GLOBULAR CLUSTERS OBSERVED BY THE APOGEE SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Mészáros, Szabolcs [ELTE Gothard Astrophysical Observatory, H-9704 Szombathely, Szent Imre Herceg st. 112 (Hungary); Martell, Sarah L. [Department of Astrophysics, School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Shetrone, Matthew [University of Texas at Austin, McDonald Observatory, Fort Davis, TX 79734 (United States); Lucatello, Sara [INAF-Osservatorio Astronomico di Padova, vicolo dell Osservatorio 5, I-35122 Padova (Italy); Troup, Nicholas W.; Pérez, Ana E. García; Majewski, Steven R. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States); Bovy, Jo [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States); Cunha, Katia [University of Arizona, Tucson, AZ 85719 (United States); García-Hernández, Domingo A.; Prieto, Carlos Allende [Instituto de Astrofísica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); Overbeek, Jamie C. [Department of Astronomy, Indiana University, Bloomington, IN 47405 (United States); Beers, Timothy C. [Department of Physics and JINA Center for the Evolution of the Elements, University of Notre Dame, Notre Dame, IN 46556 (United States); Frinchaboy, Peter M. [Texas Christian University, Fort Worth, TX 76129 (United States); Hearty, Fred R.; Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Holtzman, Jon [New Mexico State University, Las Cruces, NM 88003 (United States); Nidever, David L. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Schiavon, Ricardo P. [Astrophysics Research Institute, IC2, Liverpool Science Park, Liverpool John Moores University, 146 Brownlow Hill, Liverpool, L3 5RF (United Kingdom); and others

    2015-05-15

    We investigate the light-element behavior of red giant stars in northern globular clusters (GCs) observed by the SDSS-III Apache Point Observatory Galactic Evolution Experiment. We derive abundances of 9 elements (Fe, C, N, O, Mg, Al, Si, Ca, and Ti) for 428 red giant stars in 10 GCs. The intrinsic abundance range relative to measurement errors is examined, and the well-known C–N and Mg–Al anticorrelations are explored using an extreme-deconvolution code for the first time in a consistent way. We find that Mg and Al drive the population membership in most clusters, except in M107 and M71, the two most metal-rich clusters in our study, where the grouping is most sensitive to N. We also find a diversity in the abundance distributions, with some clusters exhibiting clear abundance bimodalities (for example M3 and M53) while others show extended distributions. The spread of Al abundances increases significantly as cluster average metallicity decreases as previously found by other works, which we take as evidence that low metallicity, intermediate mass AGB polluters were more common in the more metal-poor clusters. The statistically significant correlation of [Al/Fe] with [Si/Fe] in M15 suggests that {sup 28}Si leakage has occurred in this cluster. We also present C, N, and O abundances for stars cooler than 4500 K and examine the behavior of A(C+N+O) in each cluster as a function of temperature and [Al/Fe]. The scatter of A(C+N+O) is close to its estimated uncertainty in all clusters and independent of stellar temperature. A(C+N+O) exhibits small correlations and anticorrelations with [Al/Fe] in M3 and M13, but we cannot be certain about these relations given the size of our abundance uncertainties. Star-to-star variations of α-element (Si, Ca, Ti) abundances are comparable to our estimated errors in all clusters.

  4. Probability Measures on Groups IX

    CERN Document Server

    1989-01-01

    The latest in this series of Oberwolfach conferences focussed on the interplay between structural probability theory and various other areas of pure and applied mathematics such as Tauberian theory, infinite-dimensional rotation groups, central limit theorems, harmonizable processes, and spherical data. Thus it was attended by mathematicians whose research interests range from number theory to quantum physics in conjunction with structural properties of probabilistic phenomena. This volume contains 5 survey articles submitted on special invitation and 25 original research papers.

  5. A Deep X-ray Survey of the Globular Cluster Omega Centauri

    Science.gov (United States)

    Henleywillis, Simon; Cool, Adrienne M.; Haggard, Daryl; Heinke, Craig; Callanan, Paul; Zhao, Yue

    2018-03-01

    We identify 233 X-ray sources, of which 95 are new, in a 222 ks exposure of Omega Centauri with the Chandra X-ray Observatory's ACIS-I detector. The limiting unabsorbed flux in the core is fX(0.5-6.0 keV) ≃ 3×10-16 erg s-1 cm-2 (Lx ≃ 1×1030 erg s-1 at 5.2 kpc). We estimate that ˜60 ± 20 of these are cluster members, of which ˜30 lie within the core (rc = 155 arcsec), and another ˜30 between 1-2 core radii. We identify four new optical counterparts, for a total of 45 likely identifications. Probable cluster members include 18 cataclysmic variables (CVs) and CV candidates, one quiescent low-mass X-ray binary, four variable stars, and five stars that are either associated with ω Cen's anomalous red giant branch, or are sub-subgiants. We estimate that the cluster contains 40 ± 10 CVs with Lx > 1031 erg s-1, confirming that CVs are underabundant in ω Cen relative to the field. Intrinsic absorption is required to fit X-ray spectra of six of the nine brightest CVs, suggesting magnetic CVs, or high-inclination systems. Though no radio millisecond pulsars (MSPs) are currently known in ω Cen, more than 30 unidentified sources have luminosities and X-ray colours like those of MSPs found in other globular clusters; these could be responsible for the Fermi-detected gamma-ray emission from the cluster. Finally, we identify a CH star as the counterpart to the second-brightest X-ray source in the cluster and argue that it is a symbiotic star. This is the first such giant/white dwarf binary to be identified in a globular cluster.

  6. Cluster-cluster clustering

    International Nuclear Information System (INIS)

    Barnes, J.; Dekel, A.; Efstathiou, G.; Frenk, C.S.; Yale Univ., New Haven, CT; California Univ., Santa Barbara; Cambridge Univ., England; Sussex Univ., Brighton, England)

    1985-01-01

    The cluster correlation function xi sub c(r) is compared with the particle correlation function, xi(r) in cosmological N-body simulations with a wide range of initial conditions. The experiments include scale-free initial conditions, pancake models with a coherence length in the initial density field, and hybrid models. Three N-body techniques and two cluster-finding algorithms are used. In scale-free models with white noise initial conditions, xi sub c and xi are essentially identical. In scale-free models with more power on large scales, it is found that the amplitude of xi sub c increases with cluster richness; in this case the clusters give a biased estimate of the particle correlations. In the pancake and hybrid models (with n = 0 or 1), xi sub c is steeper than xi, but the cluster correlation length exceeds that of the points by less than a factor of 2, independent of cluster richness. Thus the high amplitude of xi sub c found in studies of rich clusters of galaxies is inconsistent with white noise and pancake models and may indicate a primordial fluctuation spectrum with substantial power on large scales. 30 references

  7. Variability in research ethics review of cluster randomized trials: a scenario-based survey in three countries

    Science.gov (United States)

    2014-01-01

    Background Cluster randomized trials (CRTs) present unique ethical challenges. In the absence of a uniform standard for their ethical design and conduct, problems such as variability in procedures and requirements by different research ethics committees will persist. We aimed to assess the need for ethics guidelines for CRTs among research ethics chairs internationally, investigate variability in procedures for research ethics review of CRTs within and among countries, and elicit research ethics chairs’ perspectives on specific ethical issues in CRTs, including the identification of research subjects. The proper identification of research subjects is a necessary requirement in the research ethics review process, to help ensure, on the one hand, that subjects are protected from harm and exploitation, and on the other, that reviews of CRTs are completed efficiently. Methods A web-based survey with closed- and open-ended questions was administered to research ethics chairs in Canada, the United States, and the United Kingdom. The survey presented three scenarios of CRTs involving cluster-level, professional-level, and individual-level interventions. For each scenario, a series of questions was posed with respect to the type of review required (full, expedited, or no review) and the identification of research subjects at cluster and individual levels. Results A total of 189 (35%) of 542 chairs responded. Overall, 144 (84%, 95% CI 79 to 90%) agreed or strongly agreed that there is a need for ethics guidelines for CRTs and 158 (92%, 95% CI 88 to 96%) agreed or strongly agreed that research ethics committees could be better informed about distinct ethical issues surrounding CRTs. There was considerable variability among research ethics chairs with respect to the type of review required, as well as the identification of research subjects. The cluster-cluster and professional-cluster scenarios produced the most disagreement. Conclusions Research ethics committees

  8. Type-Ia supernova rates to redshift 2.4 from clash: The cluster lensing and supernova survey with Hubble

    International Nuclear Information System (INIS)

    Graur, O.; Rodney, S. A.; Riess, A. G.; Medezinski, E.; Maoz, D.; Jha, S. W.; Holoien, T. W.-S.; McCully, C.; Patel, B.; Postman, M.; Dahlen, T.; Strolger, L.-G.; Coe, D.; Bradley, L.; Koekemoer, A.; Benítez, N.; Molino, A.; Jouvel, S.; Nonino, M.; Balestra, I.

    2014-01-01

    We present the supernova (SN) sample and Type-Ia SN (SN Ia) rates from the Cluster Lensing And Supernova survey with Hubble (CLASH). Using the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope (HST), we have imaged 25 galaxy-cluster fields and parallel fields of non-cluster galaxies. We report a sample of 27 SNe discovered in the parallel fields. Of these SNe, ∼13 are classified as SN Ia candidates, including four SN Ia candidates at redshifts z > 1.2. We measure volumetric SN Ia rates to redshift 1.8 and add the first upper limit on the SN Ia rate in the range 1.8 < z < 2.4. The results are consistent with the rates measured by the HST/GOODS and Subaru Deep Field SN surveys. We model these results together with previous measurements at z < 1 from the literature. The best-fitting SN Ia delay-time distribution (DTD; the distribution of times that elapse between a short burst of star formation and subsequent SN Ia explosions) is a power law with an index of −1.00 −0.06(0.10) +0.06(0.09) (statistical) −0.08 +0.12 (systematic), where the statistical uncertainty is a result of the 68% and 95% (in parentheses) statistical uncertainties reported for the various SN Ia rates (from this work and from the literature), and the systematic uncertainty reflects the range of possible cosmic star-formation histories. We also test DTD models produced by an assortment of published binary population synthesis (BPS) simulations. The shapes of all BPS double-degenerate DTDs are consistent with the volumetric SN Ia measurements, when the DTD models are scaled up by factors of 3-9. In contrast, all BPS single-degenerate DTDs are ruled out by the measurements at >99% significance level.

  9. Type-Ia Supernova Rates to Redshift 2.4 from Clash: The Cluster Lensing and Supernova Survey with Hubble

    Science.gov (United States)

    Graur, O.; Rodney, S. A.; Maoz, D.; Riess, A. G.; Jha, S. W.; Postman, M.; Dahlen, T.; Holoien, T. W.-S.; McCully, C.; Patel, B.; hide

    2014-01-01

    We present the supernova (SN) sample and Type-Ia SN (SN Ia) rates from the Cluster Lensing And Supernova survey with Hubble (CLASH). Using the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope (HST), we have imaged 25 galaxy-cluster fields and parallel fields of non-cluster galaxies. We report a sample of 27 SNe discovered in the parallel fields. Of these SNe, approximately 13 are classified as SN Ia candidates, including four SN Ia candidates at redshifts z greater than 1.2.We measure volumetric SN Ia rates to redshift 1.8 and add the first upper limit on the SN Ia rate in the range z greater than 1.8 and less than 2.4. The results are consistent with the rates measured by the HST/ GOODS and Subaru Deep Field SN surveys.We model these results together with previous measurements at z less than 1 from the literature. The best-fitting SN Ia delay-time distribution (DTD; the distribution of times that elapse between a short burst of star formation and subsequent SN Ia explosions) is a power law with an index of 1.00 (+0.06(0.09))/(-0.06(0.10)) (statistical) (+0.12/-0.08) (systematic), where the statistical uncertainty is a result of the 68% and 95% (in parentheses) statistical uncertainties reported for the various SN Ia rates (from this work and from the literature), and the systematic uncertainty reflects the range of possible cosmic star-formation histories. We also test DTD models produced by an assortment of published binary population synthesis (BPS) simulations. The shapes of all BPS double-degenerate DTDs are consistent with the volumetric SN Ia measurements, when the DTD models are scaled up by factors of 3-9. In contrast, all BPS single-degenerate DTDs are ruled out by the measurements at greater than 99% significance level.

  10. VizieR Online Data Catalog: HST/ACS Coma cluster survey. II. (Hammer+, 2010)

    NARCIS (Netherlands)

    Hammer, D.; Verdoes Kleijn, G.; Hoyos, C.; den Brok, M.; Balcells, M.; Ferguson, H. C.; Goudfrooij, P.; Carter, D.; Guzman, R.; Peletier, R. F.; Smith, R. J.; Graham, A. W.; Trentham, N.; Peng, E.; Puzia, T. H.; Lucey, J. R.; Jogee, S.; Aguerri, A. L.; Batcheldor, D.; Bridges, T. J.; Chiboucas, K.; Davies, J. I.; Del Burgo, C.; Erwin, P.; Hornschemeier, A.; Hudson, M. J.; Huxor, A.; Jenkins, L.; Karick, A.; Khosroshahi, H.; Kourkchi, E.; Komiyama, Y.; Lotz, J.; Marzke, R. O.; Marinova, I.; Matkovic, A.; Merritt, D.; Miller, B. W.; Miller, N. A.; Mobasher, B.; Mouhcine, M.; Okamura, S.; Percival, S.; Phillipps, S.; Poggianti, B. M.; Price, J.; Sharples, R. M.; Tully, R. B.; Valentijn, E.

    2010-01-01

    This data release contains catalogs for the ACS Images in F475W and F814W bands of 25 fields in the Coma cluster of galaxies. Each field is about 202x202arcsec. Please see the release notes for further details. (25 data files).

  11. Properties of massive stars in four clusters of the VVV survey

    Czech Academy of Sciences Publication Activity Database

    Hervé, Anthony; Martins, F.; Chene, A.-N.; Bouret, J.-C.; Borissova, J.

    2016-01-01

    Roč. 45, May (2016), s. 84-91 ISSN 1384-1076 R&D Projects: GA ČR(CZ) GA14-02385S Institutional support: RVO:67985815 Keywords : galaxy * open clusters and associations * Wolf-Rayet Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.938, year: 2016

  12. Weak-lensing mass calibration of redMaPPer galaxy clusters in Dark Energy Survey Science Verification data

    Energy Technology Data Exchange (ETDEWEB)

    Melchior, P.; Gruen, D.; McClintock, T.; Varga, T. N.; Sheldon, E.; Rozo, E.; Amara, A.; Becker, M. R.; Benson, B. A.; Bermeo, A.; Bridle, S. L.; Clampitt, J.; Dietrich, J. P.; Hartley, W. G.; Hollowood, D.; Jain, B.; Jarvis, M.; Jeltema, T.; Kacprzak, T.; MacCrann, N.; Rykoff, E. S.; Saro, A.; Suchyta, E.; Troxel, M. A.; Zuntz, J.; Bonnett, C.; Plazas, A. A.; Abbott, T. M. C.; Abdalla, F. B.; Annis, J.; Benoit-Lévy, A.; Bernstein, G. M.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D’Andrea, C. B.; da Costa, L. N.; Desai, S.; Eifler, T. F.; Flaugher, B.; Fosalba, P.; García-Bellido, J.; Gaztanaga, E.; Gerdes, D. W.; Gruendl, R. A.; Gschwend, J.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kirk, D.; Krause, E.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Lima, M.; Maia, M. A. G.; March, M.; Martini, P.; Menanteau, F.; Miller, C. J.; Miquel, R.; Mohr, J. J.; Nichol, R. C.; Ogando, R.; Romer, A. K.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Walker, A. R.; Weller, J.; Zhang, Y.

    2017-05-16

    We use weak-lensing shear measurements to determine the mean mass of optically selected galaxy clusters in Dark Energy Survey Science Verification data. In a blinded analysis, we split the sample of more than 8,000 redMaPPer clusters into 15 subsets, spanning ranges in the richness parameter $5 \\leq \\lambda \\leq 180$ and redshift $0.2 \\leq z \\leq 0.8$, and fit the averaged mass density contrast profiles with a model that accounts for seven distinct sources of systematic uncertainty: shear measurement and photometric redshift errors; cluster-member contamination; miscentering; deviations from the NFW halo profile; halo triaxiality; and line-of-sight projections. We combine the inferred cluster masses to estimate the joint scaling relation between mass, richness and redshift, $\\mathcal{M}(\\lambda,z) \\varpropto M_0 \\lambda^{F} (1+z)^{G}$. We find $M_0 \\equiv \\langle M_{200\\mathrm{m}}\\,|\\,\\lambda=30,z=0.5\\rangle=\\left[ 2.35 \\pm 0.22\\ \\rm{(stat)} \\pm 0.12\\ \\rm{(sys)} \\right] \\cdot 10^{14}\\ M_\\odot$, with $F = 1.12\\,\\pm\\,0.20\\ \\rm{(stat)}\\, \\pm\\, 0.06\\ \\rm{(sys)}$ and $G = 0.18\\,\\pm\\, 0.75\\ \\rm{(stat)}\\, \\pm\\, 0.24\\ \\rm{(sys)}$. The amplitude of the mass-richness relation is in excellent agreement with the weak-lensing calibration of redMaPPer clusters in SDSS by Simet et al. (2016) and with the Saro et al. (2015) calibration based on abundance matching of SPT-detected clusters. Our results extend the redshift range over which the mass-richness relation of redMaPPer clusters has been calibrated with weak lensing from $z\\leq 0.3$ to $z\\leq0.8$. Calibration uncertainties of shear measurements and photometric redshift estimates dominate our systematic error budget and require substantial improvements for forthcoming studies.

  13. A deep Spitzer survey of circumstellar disks in the young double cluster, h and χ Persei

    Energy Technology Data Exchange (ETDEWEB)

    Cloutier, Ryan; Currie, Thayne; Jayawardhana, Ray [University of Toronto, 50 St. George Street, Toronto, ON, M5S 2J7 (Canada); Rieke, George H. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Kenyon, Scott J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02140 (United States); Balog, Zoltan, E-mail: cloutier@cita.utoronto.ca, E-mail: currie@astro.utoronto.ca, E-mail: grieke@as.arizona.edu, E-mail: skenyon@cfa.harvard.edu [Max Planck Institute for Astrophysics, Königstuhl 17, D-69117 Heidelberg (Germany)

    2014-12-01

    We analyze very deep Infrared Array Camera and Multiband Imaging Photometer for Spitzer (MIPS) photometry of ∼12, 500 members of the 14 Myr old Double Cluster, h and χ Persei, building upon our earlier, shallower Spitzer Cycle 1 studies. Numerous likely members show infrared (IR) excesses at 8 μm and 24 μm, indicative of circumstellar dust. The frequency of stars with 8 μm excess is at least 2% for our entire sample, slightly lower (higher) for B/A stars (later type, lower mass stars). Optical spectroscopy also identifies gas in about 2% of systems, but with no clear trend between the presence of dust and gas. Spectral energy distribution modeling of 18 sources with detections at optical wavelengths through MIPS 24 μm reveals a diverse set of disk evolutionary states, including a high fraction of transitional disks, though similar data for all disk-bearing members would provide constraints. Using Monte Carlo simulations, we combine our results with those for other young clusters to study the global evolution of dust/gas disks. For nominal cluster ages, the e-folding times (τ{sub 0}) for the frequency of warm dust and gas are 2.75 Myr and 1.75 Myr, respectively. Assuming a revised set of ages for some clusters, these timescales increase to 5.75 and 3.75 Myr, respectively, implying a significantly longer typical protoplanetary disk lifetime than previously thought. In both cases, the transitional disk duration, averaged over multiple evolutionary pathways, is ≈1 Myr. Finally, 24 μm excess frequencies for 4-6 M {sub ☉} stars appear lower than for 1-2.5 M {sub ☉} stars in other 10-30 Myr old clusters.

  14. K2: A NEW METHOD FOR THE DETECTION OF GALAXY CLUSTERS BASED ON CANADA-FRANCE-HAWAII TELESCOPE LEGACY SURVEY MULTICOLOR IMAGES

    International Nuclear Information System (INIS)

    Thanjavur, Karun; Willis, Jon; Crampton, David

    2009-01-01

    We have developed a new method, K2, optimized for the detection of galaxy clusters in multicolor images. Based on the Red Sequence approach, K2 detects clusters using simultaneous enhancements in both colors and position. The detection significance is robustly determined through extensive Monte Carlo simulations and through comparison with available cluster catalogs based on two different optical methods, and also on X-ray data. K2 also provides quantitative estimates of the candidate clusters' richness and photometric redshifts. Initially, K2 was applied to the two color (gri) 161 deg 2 images of the Canada-France-Hawaii Telescope Legacy Survey Wide (CFHTLS-W) data. Our simulations show that the false detection rate for these data, at our selected threshold, is only ∼1%, and that the cluster catalogs are ∼80% complete up to a redshift of z = 0.6 for Fornax-like and richer clusters and to z ∼ 0.3 for poorer clusters. Based on the g-, r-, and i-band photometric catalogs of the Terapix T05 release, 35 clusters/deg 2 are detected, with 1-2 Fornax-like or richer clusters every 2 deg 2 . Catalogs containing data for 6144 galaxy clusters have been prepared, of which 239 are rich clusters. These clusters, especially the latter, are being searched for gravitational lenses-one of our chief motivations for cluster detection in CFHTLS. The K2 method can be easily extended to use additional color information and thus improve overall cluster detection to higher redshifts. The complete set of K2 cluster catalogs, along with the supplementary catalogs for the member galaxies, are available on request from the authors.

  15. THE HUBBLE SPACE TELESCOPE UV LEGACY SURVEY OF GALACTIC GLOBULAR CLUSTERS. VII. IMPLICATIONS FROM THE NEARLY UNIVERSAL NATURE OF HORIZONTAL BRANCH DISCONTINUITIES

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T. M.; Bellini, A.; Anderson, J. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Cassisi, S.; Pietrinferni, A. [INAF-Osservatorio Astronomico di Teramo, Via Mentore Maggini s.n.c., I-64100 Teramo (Italy); D’Antona, F. [INAF-Osservatorio Astronomico di Roma, Via Frascati 33, I-00040 Monteporzio Catone, Roma (Italy); Salaris, M. [Astrophysics Research Institute,Liverpool John Moores University, Liverpool Science Park, IC2 Building, 146 Brownlow Hill, Liverpool L3 5RF (United Kingdom); Milone, A. P. [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston, ACT, 2611 (Australia); Dalessandro, E. [Dipartimento di Fisica e Astronomia, Università degli Studi di Bologna, Viale Berti Pichat 6/2, I-40127 Bologna (Italy); Piotto, G.; Ortolani, S.; Nardiello, D. [Dipartimento di Fisica e Astronomia “Galileo Galilei,”Università di Padova, Vicolo dell’Osservatorio 3, I-35122 Padova (Italy); Renzini, A.; Bedin, L. R. [INAF-Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy); Sweigart, A. V. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Sarajedini, A. [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Aparicio, A., E-mail: tbrown@stsci.edu, E-mail: jayander@stsci, E-mail: bellini@stsci.edu, E-mail: cassisi@oa-teramo.inaf.it, E-mail: pietrinferni@oa-teramo.inaf.it, E-mail: dantona@oa-roma.inaf.it, E-mail: M.Salaris@ljmu.ac.uk, E-mail: milone@mso.anu.edu.au [Instituto de Astrofísica de Canarias. Calle Vía Láctea s/n. E38200 — La Laguna, Tenerife, Canary Islands (Spain)

    2016-05-01

    The UV-initiative Hubble Space Telescope Treasury survey of Galactic globular clusters provides a new window into the phenomena that shape the morphological features of the horizontal branch (HB). Using this large and homogeneous catalog of UV and blue photometry, we demonstrate that the HB exhibits discontinuities that are remarkably consistent in color (effective temperature). This consistency is apparent even among some of the most massive clusters hosting multiple distinct sub-populations (such as NGC 2808, ω Cen, and NGC 6715), demonstrating that these phenomena are primarily driven by atmospheric physics that is independent of the underlying population properties. However, inconsistencies arise in the metal-rich clusters NGC 6388 and NGC 6441, where the discontinuity within the blue HB (BHB) distribution shifts ∼1000–2000 K hotter. We demonstrate that this shift is likely due to a large helium enhancement in the BHB stars of these clusters, which in turn affects the surface convection and evolution of such stars. Our survey also increases the number of Galactic globular clusters known to host blue-hook stars (also known as late hot flashers) from 6 to 23 clusters. These clusters are biased toward the bright end of the globular cluster luminosity function, confirming that blue-hook stars tend to form in the most massive clusters with significant self-enrichment.

  16. A DEEP VERY LARGE ARRAY RADIO CONTINUUM SURVEY OF THE CORE AND OUTSKIRTS OF THE COMA CLUSTER

    International Nuclear Information System (INIS)

    Miller, Neal A.; Hornschemeier, Ann E.; Mobasher, Bahram

    2009-01-01

    We present deep 1.4 GHz Very Large Array radio continuum observations of two ∼0.5 deg 2 fields in the Coma cluster of galaxies. The two fields, 'Coma 1' and 'Coma 3', correspond to the cluster core and southwest infall region and were selected on account of abundant preexisting multiwavelength data. In their most sensitive regions the radio data reach 22 μJy rms per 4.''4 beam, sufficient to detect (at 5σ) Coma member galaxies with L 1.4 G Hz = 1.3 x 10 20 W Hz -1 . The full catalog of radio detections is presented herein and consists of 1030 sources detected at ≥5σ, 628 of which are within the combined Coma 1 and Coma 3 area. We also provide optical identifications of the radio sources using data from the Sloan Digital Sky Survey. The depth of the radio observations allows us to detect active galactic nucleus in cluster elliptical galaxies with M r r r ∼ sun yr -1 .

  17. Cosmological implication of wide field Sunyaev-Zel'dovich galaxy clusters survey: exploration by simulation

    International Nuclear Information System (INIS)

    Juin, Jean-Baptiste

    2005-01-01

    The goal of my Phd research is to prepare the data analysis of the near future wide-field observations of galaxy clusters detected by Sunyaev Zel'dovitch effect. I set up a complete chain of original tools to carry out this study. These tools allow me to highlight critical and important points of selection effects that has to be taken into account in future analysis. Analysis chain is composed by: a simulation of observed millimeter sky, state-of-the-art algorithms of SZ galaxy clusters extraction from observed maps, a statistical model of selection effects of the whole detection chain and, finally, tools to constrain, from detected SZ sources catalog, the cosmological parameters. I focus myself on multi-channel experiments equipped with large bolometer camera. I use these tools for a prospecting on Olimpo experiment. (author) [fr

  18. Snapshot Survey of the Globular Cluster Populations of Isolated Early Type Galaxies

    Science.gov (United States)

    Gregg, Michael

    2017-08-01

    We propose WFC3/UVIS snapshot observations of a sample of 75 isolated early type galaxiesresiding in cosmic voids or extremely low density regions. The primary aim is to usetheir globular cluster populations to reconstruct their evolutionary history, revealingif, how, and why void ellipticals differ from cluster ellipticals. The galaxies span arange of luminosities, providing a varied sample for comparison with the well-documentedglobular cluster populations in denser environments. This proposed WFC3 study of isolatedearly type galaxies breaks new ground by targeting a sample which has thus far receivedlittle attention, and, significantly, this will be the first such study with HST.Characterizing early type galaxies in voids and their GC systems promises to increase ourunderstanding of galaxy formation and evolution of galaxies in general because isolatedobjects are the best approximation to a control sample that we have for understanding theinfluence of environment on formation and evolution. Whether these isolated objects turnout to be identical to or distinct from counterparts in other regions of the Universe,they will supply insight into the formation and evolution of all galaxies. Parallel ACSimaging will help to characterize the near field environments of the sample.

  19. Cluster Headache Clinical Phenotypes: Tobacco Nonexposed (Never Smoker and No Parental Secondary Smoke Exposure as a Child) versus Tobacco-Exposed: Results from the United States Cluster Headache Survey.

    Science.gov (United States)

    Rozen, Todd D

    2018-05-01

    To present results from the United States Cluster Headache Survey comparing the clinical presentation of tobacco nonexposed and tobacco-exposed cluster headache patients. Cluster headache is uniquely tied to a personal history of tobacco usage/cigarette smoking and, if the individual cluster headache sufferer did not smoke, it has been shown that their parent(s) typically did and that individual had significant secondary smoke exposure as a child. The true nontobacco exposed (no personal or secondary exposure) cluster headache sufferer has never been fully studied. The United States Cluster Headache Survey consisted of 187 multiple choice questions related to cluster headache including: patient demographics, clinical headache characteristics, family history, triggers, smoking history (personal and secondary), and headache-related disability. The survey was placed on a website from October through December 2008. One thousand one hundred thirty-four individuals completed the survey. One hundred thirty-three subjects or 12% of the surveyed population had no personal smoking/tobacco use history and no secondary smoke exposure as an infant/child, thus a nontobacco exposed population. In the nonexposed population, there were 87 males and 46 females with a gender ratio of 1.9:1. Episodic cluster headache occurred in 80% of nonexposed subjects. One thousand and one survey responders or 88% were tobacco-exposed (729 males and 272 females) with a gender ratio of 2.7:1. Eighty-three percent had a personal smoking history, while only 17% just had parents who smoked with secondary smoke exposure. Eighty-five percent of smokers had double exposure with a personal smoking history and secondary exposure as a child. Nonexposed cluster headache subjects are significantly more likely to develop cluster headache at ages 40 years and younger, while the exposed sufferers are significantly more likely to develop cluster headache at 40 years of age and older. Nonexposed patients have a

  20. Joint analysis of galaxy-galaxy lensing and galaxy clustering: Methodology and forecasts for Dark Energy Survey

    International Nuclear Information System (INIS)

    Park, Y.; Krause, E.; Dodelson, S.; Jain, B.; Amara, A.

    2016-01-01

    Here, the joint analysis of galaxy-galaxy lensing and galaxy clustering is a promising method for inferring the growth function of large-scale structure. Anticipating a near future application of this analysis to Dark Energy Survey (DES) measurements of galaxy positions and shapes, we develop a practical approach to modeling the assumptions and systematic effects affecting the joint analysis of small-scale galaxy-galaxy lensing and large-scale galaxy clustering. Introducing parameters that characterize the halo occupation distribution (HOD), photometric redshift uncertainties, and shear measurement errors, we study how external priors on different subsets of these parameters affect our growth constraints. Degeneracies within the HOD model, as well as between the HOD and the growth function, are identified as the dominant source of complication, with other systematic effects being subdominant. The impact of HOD parameters and their degeneracies necessitate the detailed joint modeling of the galaxy sample that we employ. We conclude that DES data will provide powerful constraints on the evolution of structure growth in the Universe, conservatively/optimistically constraining the growth function to 7.9%/4.8% with its first-year data that cover over 1000 square degrees, and to 3.9%/2.3% with its full five-year data that will survey 5000 square degrees, including both statistical and systematic uncertainties.

  1. Measuring the Scatter of the Mass–Richness Relation in Galaxy Clusters in Photometric Imaging Surveys by Means of Their Correlation Function

    Energy Technology Data Exchange (ETDEWEB)

    Campa, Julia; Estrada, Juan; Flaugher, Brenna

    2017-02-03

    The knowledge of the scatter in the mass-observable relation is a key ingredient for a cosmological analysis based on galaxy clusters in a photometric survey. We demonstrate here how the linear bias measured in the correlation function for clusters can be used to determine the value of the scatter. The new method is tested in simulations of a 5.000 square degrees optical survey up to z~1, similar to the ongoing Dark Energy Survey. The results indicate that the scatter can be measured with a precision of 5% using this technique.

  2. The Next Generation Fornax Survey (NGFS). IV. Mass and Age Bimodality of Nuclear Clusters in the Fornax Core Region

    Science.gov (United States)

    Ordenes-Briceño, Yasna; Puzia, Thomas H.; Eigenthaler, Paul; Taylor, Matthew A.; Muñoz, Roberto P.; Zhang, Hongxin; Alamo-Martínez, Karla; Ribbeck, Karen X.; Grebel, Eva K.; Ángel, Simón; Côté, Patrick; Ferrarese, Laura; Hilker, Michael; Lançon, Ariane; Mieske, Steffen; Miller, Bryan W.; Rong, Yu; Sánchez-Janssen, Ruben

    2018-06-01

    We present the analysis of 61 nucleated dwarf galaxies in the central regions (≲R vir/4) of the Fornax galaxy cluster. The galaxies and their nuclei are studied as part of the Next Generation Fornax Survey using optical imaging obtained with the Dark Energy Camera mounted at Blanco/Cerro Tololo Inter-American Observatory and near-infrared data obtained with VIRCam at VISTA/ESO. We decompose the nucleated dwarfs in nucleus and spheroid, after subtracting the surface brightness profile of the spheroid component and studying the nucleus using point source photometry. In general, nuclei are consistent with colors of confirmed metal-poor globular clusters, but with significantly smaller dispersion than other confirmed compact stellar systems in Fornax. We find a bimodal nucleus mass distribution with peaks located at {log}({{ \\mathcal M }}* /{M}ȯ )≃ 5.4 and ∼6.3. These two nucleus subpopulations have different stellar population properties: the more massive nuclei are older than ∼2 Gyr and have metal-poor stellar populations (Z ≤ 0.02 Z ⊙), while the less massive nuclei are younger than ∼2 Gyr with metallicities in the range 0.02 < Z/Z ⊙ ≤ 1. We find that the nucleus mass ({{ \\mathcal M }}nuc}) versus galaxy mass ({{ \\mathcal M }}gal}) relation becomes shallower for less massive galaxies starting around 108 M ⊙, and the mass ratio {η }n={{ \\mathcal M }}nuc}/{{ \\mathcal M }}gal} shows a clear anticorrelation with {{ \\mathcal M }}gal} for the lowest masses, reaching 10%. We test current theoretical models of nuclear cluster formation and find that they cannot fully reproduce the observed trends. A likely mixture of in situ star formation and star cluster mergers seems to be acting during nucleus growth over cosmic time.

  3. The LAMOST spectroscopic survey of globular clusters in M31 and M33. I. catalog and new identifications

    International Nuclear Information System (INIS)

    Chen, Bing-Qiu; Liu, Xiao-Wei; Xiang, Mao-Sheng; Huang, Yang; Sun, Ning-Chen; Wang, Chun; Ren, Juan-Juan; Zhang, Hua-Wei; Yuan, Hai-Bo; Rebassa-Mansergas, Alberto; Huo, Zhi-Ying; Yang, Ming; Zhang, Yong; Hou, Yong-Hui; Wang, Yue-Fei

    2015-01-01

    We present a catalog of 908 objects observed with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) in fields in the vicinity of M31 and M33, targeted as globular clusters (GCs) and candidates. The targets include known GCs and candidates selected from the literature, as well as new candidates selected from the Sloan Digital Sky Survey (SDSS). Analysis shows that 356 of them are likely GCs with various confidence levels, while the remaining ones turn out to be background galaxies and quasars, stars and H ii regions in M31 or foreground Galactic stars. The 356 likely GCs include 298 bona fide GCs and 26 candidates known in the literature. Three candidates, selected from the Revised Bologna Catalog of M31 GCs and candidates (RBC) and one possible cluster from Johnson et al., are confirmed to be bona fide clusters. We search for new GCs in the halo of the M31 among the new candidates selected from the SDSS photometry. Based on radial velocities yielded by LAMOST spectra and visual examination of the SDSS images, we find 28 objects, 5 bona fide and 23 likely GCs. Among the five bona fide GCs, three have been recently discovered independently by others, and the remaining 25 are our new identifications, including two bona fide ones. The newly identified objects fall at projected distances ranging from 13 to 265kpc from M31. Of the two newly discovered bona fide GCs, one is located near M33, probably a GC belonging to M33. The other bona fide GC falls on the Giant Stream with a projected distance of 78 kpc from M31. Of the 23 newly identified likely GCs, one has a projected distance of about 265 kpc from M31 and could be an intergalactic cluster. (paper)

  4. Handwashing in 51 Countries: Analysis of Proxy Measures of Handwashing Behavior in Multiple Indicator Cluster Surveys and Demographic and Health Surveys, 2010–2013

    Science.gov (United States)

    Kumar, Swapna; Loughnan, Libbet; Luyendijk, Rolf; Hernandez, Orlando; Weinger, Merri; Arnold, Fred; Ram, Pavani K.

    2017-01-01

    Abstract. In 2009, a common set of questions addressing handwashing behavior was introduced into nationally representative Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Surveys (MICS), providing large amounts of comparable data from numerous countries worldwide. The objective of this analysis is to describe global handwashing patterns using two proxy indicators for handwashing behavior from 51 DHS and MICS surveys conducted in 2010–2013: availability of soap anywhere in the dwelling and access to a handwashing place with soap and water. Data were also examined across geographic regions, wealth quintiles, and rural versus urban settings. We found large disparities for both indicators across regions, and even among countries within the same World Health Organization region. Within countries, households in lower wealth quintiles and in rural areas were less likely to have soap anywhere in the dwelling and at designated handwashing locations than households in higher wealth quintiles and urban areas. In addition, disparities existed among various geographic regions within countries. This analysis demonstrates the need to promote access to handwashing materials and placement at handwashing locations in the dwelling, particularly in poorer, rural areas where children are more vulnerable to handwashing-preventable syndromes such as pneumonia and diarrhea. PMID:28722572

  5. Handwashing in 51 Countries: Analysis of Proxy Measures of Handwashing Behavior in Multiple Indicator Cluster Surveys and Demographic and Health Surveys, 2010-2013.

    Science.gov (United States)

    Kumar, Swapna; Loughnan, Libbet; Luyendijk, Rolf; Hernandez, Orlando; Weinger, Merri; Arnold, Fred; Ram, Pavani K

    2017-08-01

    In 2009, a common set of questions addressing handwashing behavior was introduced into nationally representative Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Surveys (MICS), providing large amounts of comparable data from numerous countries worldwide. The objective of this analysis is to describe global handwashing patterns using two proxy indicators for handwashing behavior from 51 DHS and MICS surveys conducted in 2010-2013: availability of soap anywhere in the dwelling and access to a handwashing place with soap and water. Data were also examined across geographic regions, wealth quintiles, and rural versus urban settings. We found large disparities for both indicators across regions, and even among countries within the same World Health Organization region. Within countries, households in lower wealth quintiles and in rural areas were less likely to have soap anywhere in the dwelling and at designated handwashing locations than households in higher wealth quintiles and urban areas. In addition, disparities existed among various geographic regions within countries. This analysis demonstrates the need to promote access to handwashing materials and placement at handwashing locations in the dwelling, particularly in poorer, rural areas where children are more vulnerable to handwashing-preventable syndromes such as pneumonia and diarrhea.

  6. The Eclipse system for surveying the guide tubes of control rod clusters

    International Nuclear Information System (INIS)

    Pace, Y.M.

    2008-01-01

    Eclipse is a new system developed by Areva to assess the wear of the guide tubes of control rod clusters. This system is based on the projection of a shadow on a light plan in order to record the profile and the internal diameter of a hollow tube. This system allows us to quantify the wear and it can be included in a program dedicated to monitor the wear and master its kinetics. This system has been validated on the guide tubes from the Ringhals units. (A.C.)

  7. Evaluation of factor IX deficiency by interdigitated electrode (IDE)

    Science.gov (United States)

    Gopinath, Subash C. B.; Hashim, Uda; Uda, M. N. A.

    2017-03-01

    Factor IX deficiency is the main cause of hemophilia A and B. This a severe excessive bleeding disorder that can even kill the patient if not treated with the right prescription of Factor IX hormone to stop the bleeding. The bleeding can be caused by an injury or even a sudden bleeding in some very rare cases. To find the Factor IX effectiveness and to understand the deficiency more carefully for the future of medicine, experiments are conducted to test the Factor IX using the Interdigitated Electrode (IDE) and gold Nanoparticle with the help of Nanoelectrical technology.

  8. MOCCA-SURVEY Database I: Galactic Globular Clusters Harbouring a Black Hole Subsystem

    Science.gov (United States)

    Askar, Abbas; Sedda, Manuel Arca; Giersz, Mirek

    2018-05-01

    There have been increasing theoretical speculations and observational indications that certain globular clusters (GCs) could contain a sizeable population of stellar mass black holes (BHs). In this paper, we shortlist at least 29 Galactic GCs that could be hosting a subsystem of BHs (BHS). In a companion paper, we analysed results from a wide array of GC models (simulated with the MOCCA code for cluster simulations) that retained few tens to several hundreds of BHs at 12 Gyr and showed that the properties of the BHS in those GCs correlate with the GC's observable properties. Building on those results, we use available observational properties of 140 Galactic GCs to identify 29 GCs that could potentially be harbouring up to a few hundreds of BHs. Utilizing observational properties and theoretical scaling relations, we estimate the density, size and mass of the BHS in these GCs. We also calculate the total number of BHs and the fraction of BHs contained in a binary system for our shortlisted Galactic GCs. Additionally, we mention other Galactic GCs that could also contain significant number of single BHs or BHs in binary systems.

  9. The VMC survey. XXVIII. Improved measurements of the proper motion of the Galactic globular cluster 47 Tucanae

    Science.gov (United States)

    Niederhofer, Florian; Cioni, Maria-Rosa L.; Rubele, Stefano; Schmidt, Thomas; Bekki, Kenji; de Grijs, Richard; Emerson, Jim; Ivanov, Valentin D.; Oliveira, Joana M.; Petr-Gotzens, Monika G.; Ripepi, Vincenzo; Sun, Ning-Chen; van Loon, Jacco Th.

    2018-05-01

    We use deep multi-epoch point-spread function (PSF) photometry taken with the Visible and Infrared Survey Telescope for Astronomy (VISTA) to measure and analyze the proper motions of stars within the Galactic globular cluster 47 Tucanae (47 Tuc, NGC 104). The observations are part of the ongoing near-infrared VISTA survey of the Magellanic Cloud system (VMC). The data analyzed in this study correspond to one VMC tile, which covers a total sky area of 1.77 deg2. Absolute proper motions with respect to 9070 background galaxies are calculated from a linear regression model applied to the positions of stars in 11 epochs in the Ks filter. The data extend over a total time baseline of about 17 months. We found an overall median proper motion of the stars within 47 Tuc of (μαcos(δ), μδ) = (+5.89 ± 0.02 (statistical) ± 0.13 (systematic), -2.14 ± 0.02 (statistical) ± 0.08 (systematic)) mas yr-1, based on the measurements of 35 000 individual sources between 5' and 42' from the cluster center. We compared our result to the proper motions from the newest US Naval Observatory CCD Astrograph Catalog (UCAC5), which includes data from the Gaia data release 1. Selecting cluster members ( 2700 stars), we found a median proper motion of (μαcos(δ), μδ) = (+5.30 ± 0.03 (statistical) ± 0.70 (systematic), -2.70 ± 0.03 (statistical) ± 0.70 (systematic)) mas yr-1. Comparing the results with measurements in the literature, we found that the values derived from the VMC data are consistent with the UCAC5 result, and are close to measurements obtained using the Hubble Space Telescope. We combined our proper motion results with radial velocity measurements from the literature and reconstructed the orbit of 47 Tuc, finding that the cluster is on an orbit with a low ellipticity and is confined within the inner 7.5 kpc of the Galaxy. We show that the use of an increased time baseline in combination with PSF-determined stellar centroids in crowded regions significantly improves

  10. The GALEX Ultraviolet Virgo Cluster Survey (GUViCS). VII. Brightest cluster galaxy UV upturn and the FUV-NUV color up to redshift 0.35

    Science.gov (United States)

    Boissier, S.; Cucciati, O.; Boselli, A.; Mei, S.; Ferrarese, L.

    2018-03-01

    Context. At low redshift, early-type galaxies often exhibit a rising flux with decreasing wavelength in the 1000-2500 Å range, called "UV upturn". The origin of this phenomenon is debated, and its evolution with redshift is poorly constrained. The observed GALEX FUV-NUV color can be used to probe the UV upturn approximately to redshift 0.5. Aim. We provide constraints on the existence of the UV upturn up to redshift 0.4 in the brightest cluster galaxies (BCG) located behind the Virgo cluster, using data from the GUViCS survey. Methods: We estimate the GALEX far-UV (FUV) and near-UV (NUV) observed magnitudes for BCGs from the maxBCG catalog in the GUViCS fields. We increase the number of nonlocal galaxies identified as BCGs with GALEX photometry from a few tens of galaxies to 166 (64 when restricting this sample to relatively small error bars). We also estimate a central color within a 20 arcsec aperture. By using the r-band luminosity from the maxBCG catalog, we can separate blue FUV-NUV due to recent star formation and candidate upturn cases. We use Lick indices to verify their similarity to redshift 0 upturn cases. Results: We clearly detect a population of blue FUV-NUV BCGs in the redshift range 0.10-0.35, vastly improving the existing constraints at these epochs by increasing the number of galaxies studied, and by exploring a redshift range with no previous data (beyond 0.2), spanning one more Gyr in the past. These galaxies bring new constraints that can help distinguish between assumptions concerning the stellar populations causing the UV upturn phenomenon. The existence of a large number of UV upturns around redshift 0.25 favors the existence of a binary channel among the sources proposed in the literature. Tables 2-5 are available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A42

  11. Yellow fever vaccination coverage following massive emergency immunization campaigns in rural Uganda, May 2011: a community cluster survey

    Science.gov (United States)

    2013-01-01

    Background Following an outbreak of yellow fever in northern Uganda in December 2010, Ministry of Health conducted a massive emergency vaccination campaign in January 2011. The reported vaccination coverage in Pader District was 75.9%. Administrative coverage though timely, is affected by incorrect population estimates and over or under reporting of vaccination doses administered. This paper presents the validated yellow fever vaccination coverage following massive emergency immunization campaigns in Pader district. Methods A cross sectional cluster survey was carried out in May 2011 among communities in Pader district and 680 respondents were indentified using the modified World Health Organization (WHO) 40 × 17 cluster survey sampling methodology. Respondents were aged nine months and above. Interviewer administered questionnaires were used to collect data on demographic characteristics, vaccination status and reasons for none vaccination. Vaccination status was assessed using self reports and vaccination card evidence. Our main outcomes were measures of yellow fever vaccination coverage in each age-specific stratum, overall, and disaggregated by age and sex, adjusting for the clustered design and the size of the population in each stratum. Results Of the 680 survey respondents, 654 (96.1%, 95% CI 94.9 – 97.8) reported being vaccinated during the last campaign but only 353 (51.6%, 95% CI 47.2 – 56.1) had valid yellow fever vaccination cards. Of the 280 children below 5 years, 269 (96.1%, 95% CI 93.7 – 98.7) were vaccinated and nearly all males 299 (96.9%, 95% CI 94.3 – 99.5) were vaccinated. The main reasons for none vaccination were; having travelled out of Pader district during the campaign period (40.0%), lack of transport to immunization posts (28.0%) and, sickness at the time of vaccination (16.0%). Conclusions Our results show that actual yellow fever vaccination coverage was high and satisfactory in Pader district since it was above the

  12. Carbonic anhydrase IX (CA IX) mediates tumor cell interactions with microenvironment

    Czech Academy of Sciences Publication Activity Database

    Závadová, Zuzana; Závada, Jan

    2005-01-01

    Roč. 13, č. 5 (2005), s. 977-982 ISSN 1021-335X R&D Projects: GA ČR(CZ) GA203/02/0405 Institutional research plan: CEZ:AV0Z50520514 Keywords : carbonic anhydrase IX * cell adhesion * microenvironment Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.572, year: 2005

  13. A Chemical Composition Survey of the Iron-complex Globular Cluster NGC 6273 (M19)

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Christian I.; Caldwell, Nelson [Harvard–Smithsonian Center for Astrophysics, 60 Garden Street, MS-15, Cambridge, MA 02138 (United States); Rich, R. Michael [Department of Physics and Astronomy, UCLA, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547 (United States); Mateo, Mario [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Bailey, John I. III [Leiden Observatory, Leiden University, P.O. Box 9513, 2300RA Leiden (Netherlands); Clarkson, William I. [Department of Natural Sciences, University of Michigan–Dearborn, 4901 Evergreen Road, Dearborn, MI 48128 (United States); Olszewski, Edward W. [Steward Observatory, The University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Walker, Matthew G., E-mail: cjohnson@cfa.harvard.edu, E-mail: ncaldwell@cfa.harvard.edu, E-mail: rmr@astro.ucla.edu, E-mail: mmateo@umich.edu, E-mail: baileyji@strw.leidenuniv.nl, E-mail: wiclarks@umich.edu, E-mail: eolszewski@as.arizona.edu, E-mail: mgwalker@andrew.cmu.edu [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States)

    2017-02-20

    Recent observations have shown that a growing number of the most massive Galactic globular clusters contain multiple populations of stars with different [Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been recognized as a member of this “iron-complex” cluster class, and we provide here a chemical and kinematic analysis of >300 red giant branch and asymptotic giant branch member stars using high-resolution spectra obtained with the Magellan –M2FS and VLT–FLAMES instruments. Multiple lines of evidence indicate that NGC 6273 possesses an intrinsic metallicity spread that ranges from about [Fe/H] = −2 to −1 dex, and may include at least three populations with different [Fe/H] values. The three populations identified here contain separate first (Na/Al-poor) and second (Na/Al-rich) generation stars, but a Mg–Al anti-correlation may only be present in stars with [Fe/H] ≳ −1.65. The strong correlation between [La/Eu] and [Fe/H] suggests that the s-process must have dominated the heavy element enrichment at higher metallicities. A small group of stars with low [ α /Fe] is identified and may have been accreted from a former surrounding field star population. The cluster’s large abundance variations are coupled with a complex, extended, and multimodal blue horizontal branch (HB). The HB morphology and chemical abundances suggest that NGC 6273 may have an origin that is similar to ω Cen and M54.

  14. HOMOGENEOUS UGRIZ PHOTOMETRY FOR ACS VIRGO CLUSTER SURVEY GALAXIES: A NON-PARAMETRIC ANALYSIS FROM SDSS IMAGING

    International Nuclear Information System (INIS)

    Chen, Chin-Wei; Cote, Patrick; Ferrarese, Laura; West, Andrew A.; Peng, Eric W.

    2010-01-01

    We present photometric and structural parameters for 100 ACS Virgo Cluster Survey (ACSVCS) galaxies based on homogeneous, multi-wavelength (ugriz), wide-field SDSS (DR5) imaging. These early-type galaxies, which trace out the red sequence in the Virgo Cluster, span a factor of nearly ∼10 3 in g-band luminosity. We describe an automated pipeline that generates background-subtracted mosaic images, masks field sources and measures mean shapes, total magnitudes, effective radii, and effective surface brightnesses using a model-independent approach. A parametric analysis of the surface brightness profiles is also carried out to obtain Sersic-based structural parameters and mean galaxy colors. We compare the galaxy parameters to those in the literature, including those from the ACSVCS, finding good agreement in most cases, although the sizes of the brightest, and most extended, galaxies are found to be most uncertain and model dependent. Our photometry provides an external measurement of the random errors on total magnitudes from the widely used Virgo Cluster Catalog, which we estimate to be σ(B T )∼ 0.13 mag for the brightest galaxies, rising to ∼ 0.3 mag for galaxies at the faint end of our sample (B T ∼ 16). The distribution of axial ratios of low-mass ( d warf ) galaxies bears a strong resemblance to the one observed for the higher-mass ( g iant ) galaxies. The global structural parameters for the full galaxy sample-profile shape, effective radius, and mean surface brightness-are found to vary smoothly and systematically as a function of luminosity, with unmistakable evidence for changes in structural homology along the red sequence. As noted in previous studies, the ugriz galaxy colors show a nonlinear but smooth variation over a ∼7 mag range in absolute magnitude, with an enhanced scatter for the faintest systems that is likely the signature of their more diverse star formation histories.

  15. A Chandra Survey of Milky Way Globular Clusters. I. Emissivity and Abundance of Weak X-Ray Sources

    Science.gov (United States)

    Cheng, Zhongqun; Li, Zhiyuan; Xu, Xiaojie; Li, Xiangdong

    2018-05-01

    Based on archival Chandra data, we have carried out an X-ray survey of 69, or nearly half the known population of, Milky Way globular clusters (GCs), focusing on weak X-ray sources, mainly cataclysmic variables (CVs) and coronally active binaries (ABs). Using the cumulative X-ray luminosity per unit stellar mass (i.e., X-ray emissivity) as a proxy of the source abundance, we demonstrate a paucity (lower by 41% ± 27% on average) of weak X-ray sources in most GCs relative to the field, which is represented by the Solar Neighborhood and Local Group dwarf elliptical galaxies. We also revisit the mutual correlations among the cumulative X-ray luminosity (L X), cluster mass (M), and stellar encounter rate (Γ), finding {L}{{X}}\\propto {M}0.74+/- 0.13, {L}{{X}}\\propto {{{Γ }}}0.67+/- 0.07 and {{Γ }}\\propto {M}1.28+/- 0.17. The three quantities can further be expressed as {L}{{X}}\\propto {M}0.64+/- 0.12 {{{Γ }}}0.19+/- 0.07, which indicates that the dynamical formation of CVs and ABs through stellar encounters in GCs is less dominant than previously suggested, and that the primordial formation channel has a substantial contribution. Taking these aspects together, we suggest that a large fraction of primordial, soft binaries have been disrupted in binary–single or binary–binary stellar interactions before they could otherwise evolve into X-ray-emitting close binaries, whereas the same interactions also have led to the formation of new close binaries. No significant correlations between {L}{{X}}/{L}K and cluster properties, including dynamical age, metallicity, and structural parameters, are found.

  16. The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters - XII. The RGB bumps of multiple stellar populations

    Science.gov (United States)

    Lagioia, E. P.; Milone, A. P.; Marino, A. F.; Cassisi, S.; Aparicio, A. J.; Piotto, G.; Anderson, J.; Barbuy, B.; Bedin, L. R.; Bellini, A.; Brown, T.; D'Antona, F.; Nardiello, D.; Ortolani, S.; Pietrinferni, A.; Renzini, A.; Salaris, M.; Sarajedini, A.; van der Marel, R.; Vesperini, E.

    2018-04-01

    The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters is providing a major breakthrough in our knowledge of globular clusters (GCs) and their stellar populations. Among the main results, we discovered that all the studied GCs host two main discrete groups consisting of first generation (1G) and second generation (2G) stars. We exploit the multiwavelength photometry from this project to investigate, for the first time, the Red Giant Branch Bump (RGBB) of the two generations in a large sample of GCs. We identified, with high statistical significance, the RGBB of 1G and 2G stars in 26 GCs and found that their magnitude separation as a function of the filter wavelength follows comparable trends. The comparison of observations to synthetic spectra reveals that the RGBB luminosity depends on the stellar chemical composition and that the 2G RGBB is consistent with stars enhanced in He and N and depleted in C and O with respect to 1G stars. For metal-poor GCs the 1G and 2G RGBB relative luminosity in optical bands mostly depends on helium content, Y. We used the RGBB observations in F606W and F814W bands to infer the relative helium abundance of 1G and 2G stars in 18 GCs, finding an average helium enhancement ΔY = 0.011 ± 0.002 of 2G stars with respect to 1G stars. This is the first determination of the average difference in helium abundance of multiple populations in a large number of clusters and provides a lower limit to the maximum internal variation of helium in GCs.

  17. Large-scale clustering of galaxies in the CfA Redshift Survey

    Science.gov (United States)

    Vogeley, Michael S.; Park, Changbom; Geller, Margaret J.; Huchra, John P.

    1992-01-01

    The power spectrum of the galaxy distribution in the Center for Astrophysics Redshift Survey (de Lapparent et al., 1986; Geller and Huchra, 1989; and Huchra et al., 1992) is measured up to wavelengths of 200/h Mpc. Results are compared with several cosmological simulations with Gaussian initial conditions. It is shown that the power spectrum of the standard CDM model is inconsistent with the observed power spectrum at the 99 percent confidence level.

  18. A cross-sectional, randomized cluster sample survey of household vulnerability to extreme heat among slum dwellers in ahmedabad, india.

    Science.gov (United States)

    Tran, Kathy V; Azhar, Gulrez S; Nair, Rajesh; Knowlton, Kim; Jaiswal, Anjali; Sheffield, Perry; Mavalankar, Dileep; Hess, Jeremy

    2013-06-18

    Extreme heat is a significant public health concern in India; extreme heat hazards are projected to increase in frequency and severity with climate change. Few of the factors driving population heat vulnerability are documented, though poverty is a presumed risk factor. To facilitate public health preparedness, an assessment of factors affecting vulnerability among slum dwellers was conducted in summer 2011 in Ahmedabad, Gujarat, India. Indicators of heat exposure, susceptibility to heat illness, and adaptive capacity, all of which feed into heat vulnerability, was assessed through a cross-sectional household survey using randomized multistage cluster sampling. Associations between heat-related morbidity and vulnerability factors were identified using multivariate logistic regression with generalized estimating equations to account for clustering effects. Age, preexisting medical conditions, work location, and access to health information and resources were associated with self-reported heat illness. Several of these variables were unique to this study. As sociodemographics, occupational heat exposure, and access to resources were shown to increase vulnerability, future interventions (e.g., health education) might target specific populations among Ahmedabad urban slum dwellers to reduce vulnerability to extreme heat. Surveillance and evaluations of future interventions may also be worthwhile.

  19. MOCCA-SURVEY Database. I. Eccentric Black Hole Mergers during Binary–Single Interactions in Globular Clusters

    Science.gov (United States)

    Samsing, Johan; Askar, Abbas; Giersz, Mirek

    2018-03-01

    We estimate the population of eccentric gravitational wave (GW) binary black hole (BBH) mergers forming during binary–single interactions in globular clusters (GCs), using ∼800 GC models that were evolved using the MOCCA code for star cluster simulations as part of the MOCCA-Survey Database I project. By re-simulating BH binary–single interactions extracted from this set of GC models using an N-body code that includes GW emission at the 2.5 post-Newtonian level, we find that ∼10% of all the BBHs assembled in our GC models that merge at present time form during chaotic binary–single interactions, and that about half of this sample have an eccentricity >0.1 at 10 Hz. We explicitly show that this derived rate of eccentric mergers is ∼100 times higher than one would find with a purely Newtonian N-body code. Furthermore, we demonstrate that the eccentric fraction can be accurately estimated using a simple analytical formalism when the interacting BHs are of similar mass, a result that serves as the first successful analytical description of eccentric GW mergers forming during three-body interactions in realistic GCs.

  20. Survey of microsatellite clustering in eight fully sequenced species sheds light on the origin of compound microsatellites

    Directory of Open Access Journals (Sweden)

    Lelley Tamas

    2008-12-01

    Full Text Available Abstract Background Compound microsatellites are a special variation of microsatellites in which two or more individual microsatellites are found directly adjacent to each other. Until now, such composite microsatellites have not been investigated in a comprehensive manner. Results Our in silico survey of microsatellite clustering in genomes of Homo sapiens, Maccaca mulatta, Mus musculus, Rattus norvegicus, Ornithorhynchus anatinus, Gallus gallus, Danio rerio and Drosophila melanogaster revealed an unexpected high abundance of compound microsatellites. About 4 – 25% of all microsatellites could be categorized as compound microsatellites. Compound microsatellites are approximately 15 times more frequent than expected under the assumption of a random distribution of microsatellites. Interestingly, microsatellites do not only tend to cluster but the adjacent repeat types of compound microsatellites have very similar motifs: in most cases (>90% these motifs differ only by a single mutation (base substitution or indel. We propose that the majority of the compound microsatellites originates by duplication of imperfections in a microsatellite tract. This process occurs mostly at the end of a microsatellite, leading to a new repeat type and a potential microsatellite repeat track. Conclusion Our findings suggest a more dynamic picture of microsatellite evolution than previously believed. Imperfections within microsatellites might not only cause the "death" of microsatellites they might also result in their "birth".

  1. Combining Cluster Analysis and Small Unmanned Aerial Systems (sUAS) for Accurate and Low-cost Bathymetric Surveying

    Science.gov (United States)

    Maples, B. L.; Alvarez, L. V.; Moreno, H. A.; Chilson, P. B.; Segales, A.

    2017-12-01

    Given that classical in-situ direct surveying for geomorphological subsurface information in rivers is time-consuming, labor-intensive, costly, and often involves high-risk activities, it is obvious that non-intrusive technologies, like UAS-based, LIDAR-based remote sensing, have a promising potential and benefits in terms of efficient and accurate measurement of channel topography over large areas within a short time; therefore, a tremendous amount of attention has been paid to the development of these techniques. Over the past two decades, efforts have been undertaken to develop a specialized technique that can penetrate the water body and detect the channel bed to derive river and coastal bathymetry. In this research, we develop a low-cost effective technique for water body bathymetry. With the use of a sUAS and a light-weight sonar, the bathymetry and volume of a small reservoir have been surveyed. The sUAS surveying approach is conducted under low altitudes (2 meters from the water) using the sUAS to tow a small boat with the sonar attached. A cluster analysis is conducted to optimize the sUAS data collection and minimize the standard deviation created by under-sampling in areas of highly variable bathymetry, so measurements are densified in regions featured by steep slopes and drastic changes in the reservoir bed. This technique provides flexibility, efficiency, and free-risk to humans while obtaining high-quality information. The irregularly-spaced bathymetric survey is then interpolated using unstructured Triangular Irregular Network (TIN)-based maps to avoid re-gridding or re-sampling issues.

  2. Ares I-X Ground Diagnostic Prototype

    Science.gov (United States)

    Schwabacher, Mark A.; Martin, Rodney Alexander; Waterman, Robert D.; Oostdyk, Rebecca Lynn; Ossenfort, John P.; Matthews, Bryan

    2010-01-01

    The automation of pre-launch diagnostics for launch vehicles offers three potential benefits: improving safety, reducing cost, and reducing launch delays. The Ares I-X Ground Diagnostic Prototype demonstrated anomaly detection, fault detection, fault isolation, and diagnostics for the Ares I-X first-stage Thrust Vector Control and for the associated ground hydraulics while the vehicle was in the Vehicle Assembly Building at Kennedy Space Center (KSC) and while it was on the launch pad. The prototype combines three existing tools. The first tool, TEAMS (Testability Engineering and Maintenance System), is a model-based tool from Qualtech Systems Inc. for fault isolation and diagnostics. The second tool, SHINE (Spacecraft Health Inference Engine), is a rule-based expert system that was developed at the NASA Jet Propulsion Laboratory. We developed SHINE rules for fault detection and mode identification, and used the outputs of SHINE as inputs to TEAMS. The third tool, IMS (Inductive Monitoring System), is an anomaly detection tool that was developed at NASA Ames Research Center. The three tools were integrated and deployed to KSC, where they were interfaced with live data. This paper describes how the prototype performed during the period of time before the launch, including accuracy and computer resource usage. The paper concludes with some of the lessons that we learned from the experience of developing and deploying the prototype.

  3. Title IX--Beyond Compliance to Personal Commitment and Leadership

    Science.gov (United States)

    Peterson, Barbara

    1976-01-01

    In order to move beyond legal compliance to real equality of opportunity, every educational leader must develop some systematic means of extending his or her personal knowledge and skills with respect to Title IX. Provides a check list for self evaluation of educational leaders and a guide for developing an implementation plan for Title IX.…

  4. A License for Bias: Sex Discrimination, Schools, and Title IX.

    Science.gov (United States)

    Morse, Susan Ed.

    This report discusses non-sports-related Title IX complaints filed with the Department of Education's Office for Civil Rights (OCR) from 1993-1997. Its purpose is to dispel the popular belief that Title IX is a sports-equity law and to determine the effectiveness of the legislation. The document examines the kinds of complaints filed, the status…

  5. Tissue-specific expression of type IX collagen

    International Nuclear Information System (INIS)

    Nishimura, I.; Muragaki, Y.; Ninomiya, Y.; Olsen, B.R.; Hayashi, M.

    1990-01-01

    This paper reports on the tissue-specific expression of type IX collagen, a major component of cartilage fibrils. It contains molecules with three genetically distinct subunits. The subunits form three triple-helical (CO) domains separated by non-triple-helical (NC) sequences. One of the subunits in cartilage, α1(IX), contains a large amino-terminal globular domain, NC4, while a second subunit, α2(IX), contains a covalently attached chondroitin sulfate chain. The site of attachment for this chain is located within the non-triple-helical sequence NC3, which separates the amino-terminal and central triple-helical domains of the type IX molecules. The NC3 region is 5 amino acid residues longer in the α2(IX) chain than in the α1(IX) and α3(IX) chains. This may explain why type IX molecules tend to show a sharp angle in the NC3 region, and why monoclonal antibody molecules that are specific for the stub left after chondroitinase ABC digestion of the chondroitin sulfate side chain always are located on the outside of the angle

  6. The History, Uses, and Abuses of Title IX. 2016 Bulletin

    Science.gov (United States)

    American Association of University Professors, 2016

    2016-01-01

    This report, an evaluation of the history and current uses of Title IX, is the result of a joint effort by a subcommittee that included members of the AAUP's Committee A on Academic Freedom and Tenure and the Committee on Women in the Academic Profession. The report identifies tensions between current interpretations of Title IX and the academic…

  7. Intrinsic thermodynamics of inhibitor binding to human carbonic anhydrase IX.

    Science.gov (United States)

    Linkuvienė, Vaida; Matulienė, Jurgita; Juozapaitienė, Vaida; Michailovienė, Vilma; Jachno, Jelena; Matulis, Daumantas

    2016-04-01

    Human carbonic anhydrase 9th isoform (CA IX) is an important marker of numerous cancers and is increasingly interesting as a potential anticancer drug target. Various synthetic aromatic sulfonamide-bearing compounds are being designed as potent inhibitors of CA IX. However, sulfonamide compound binding to CA IX is linked to several reactions, the deprotonation of the sulfonamide amino group and the protonation of the CA active site Zn(II)-bound hydroxide. These linked reactions significantly affect the affinities and other thermodynamic parameters such as enthalpies and entropies of binding. The observed and intrinsic affinities of compound binding to CA IX were determined by the fluorescent thermal shift assay. The enthalpies and entropies of binding were determined by the isothermal titration calorimetry. The pKa of CA IX was determined to be 6.8 and the enthalpy of CA IX-Zn(II)-bound hydroxide protonation was -24 kJ/mol. These values enabled the analysis of intrinsic thermodynamics of a library of compounds binding to CA IX. The most strongly binding compounds exhibited the intrinsic affinity of 0.01 nM and the observed affinity of 2 nM. The intrinsic thermodynamic parameters of compound binding to CA IX helped to draw the compound structure to thermodynamics relationship. It is important to distinguish the intrinsic from observed parameters of any disease target protein interaction with its inhibitors as drug candidates when drawing detailed compound structure to thermodynamics correlations. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. A homogeneous photometric and spectroscopic survey of open clusters in the Perseus Arm

    Science.gov (United States)

    Marco, Amparo; Negueruela, Ignacio; Monguió, Maria

    2015-08-01

    We are carrying out a homogeneous photometric survey of all young (Isaac Newton Telescope in La Palma. We intend to derive relative ages and distances with typical accuracies of 5 Ma and 200 pc. Our data will allow us to test the predictions of different models for the main mechanism producing the spiral structure of the Milky Way. In addition, we will enormously improve our knowledge of stellar evolution for stars in the 6-15 Msolar range. Moreover, the huge dataset of homogeneous photometry for thousands of stars (including ~2000 B-type stars) will have an enormous legacy value

  9. THE SLUGGS SURVEY: NGC 3115, A CRITICAL TEST CASE FOR METALLICITY BIMODALITY IN GLOBULAR CLUSTER SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Brodie, Jean P.; Conroy, Charlie; Arnold, Jacob A.; Romanowsky, Aaron J. [University of California Observatories and Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Usher, Christopher; Forbes, Duncan A. [Centre for Astrophysics and Supercomputing, Swinburne University, Hawthorn, VIC 3122 (Australia); Strader, Jay, E-mail: brodie@ucolick.org [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)

    2012-11-10

    Due to its proximity (9 Mpc) and the strongly bimodal color distribution of its spectroscopically well-sampled globular cluster (GC) system, the early-type galaxy NGC 3115 provides one of the best available tests of whether the color bimodality widely observed in GC systems generally reflects a true metallicity bimodality. Color bimodality has alternatively been attributed to a strongly nonlinear color-metallicity relation reflecting the influence of hot horizontal-branch stars. Here, we couple Subaru Suprime-Cam gi photometry with Keck/DEIMOS spectroscopy to accurately measure GC colors and a CaT index that measures the Ca II triplet. We find the NGC 3115 GC system to be unambiguously bimodal in both color and the CaT index. Using simple stellar population models, we show that the CaT index is essentially unaffected by variations in horizontal-branch morphology over the range of metallicities relevant to GC systems (and is thus a robust indicator of metallicity) and confirm bimodality in the metallicity distribution. We assess the existing evidence for and against multiple metallicity subpopulations in early- and late-type galaxies and conclude that metallicity bi/multimodality is common. We briefly discuss how this fundamental characteristic links directly to the star formation and assembly histories of galaxies.

  10. THE SLUGGS SURVEY: NGC 3115, A CRITICAL TEST CASE FOR METALLICITY BIMODALITY IN GLOBULAR CLUSTER SYSTEMS

    International Nuclear Information System (INIS)

    Brodie, Jean P.; Conroy, Charlie; Arnold, Jacob A.; Romanowsky, Aaron J.; Usher, Christopher; Forbes, Duncan A.; Strader, Jay

    2012-01-01

    Due to its proximity (9 Mpc) and the strongly bimodal color distribution of its spectroscopically well-sampled globular cluster (GC) system, the early-type galaxy NGC 3115 provides one of the best available tests of whether the color bimodality widely observed in GC systems generally reflects a true metallicity bimodality. Color bimodality has alternatively been attributed to a strongly nonlinear color-metallicity relation reflecting the influence of hot horizontal-branch stars. Here, we couple Subaru Suprime-Cam gi photometry with Keck/DEIMOS spectroscopy to accurately measure GC colors and a CaT index that measures the Ca II triplet. We find the NGC 3115 GC system to be unambiguously bimodal in both color and the CaT index. Using simple stellar population models, we show that the CaT index is essentially unaffected by variations in horizontal-branch morphology over the range of metallicities relevant to GC systems (and is thus a robust indicator of metallicity) and confirm bimodality in the metallicity distribution. We assess the existing evidence for and against multiple metallicity subpopulations in early- and late-type galaxies and conclude that metallicity bi/multimodality is common. We briefly discuss how this fundamental characteristic links directly to the star formation and assembly histories of galaxies.

  11. A PARAMETERIZED GALAXY CATALOG SIMULATOR FOR TESTING CLUSTER FINDING, MASS ESTIMATION, AND PHOTOMETRIC REDSHIFT ESTIMATION IN OPTICAL AND NEAR-INFRARED SURVEYS

    International Nuclear Information System (INIS)

    Song, Jeeseon; Mohr, Joseph J.; Barkhouse, Wayne A.; Rude, Cody; Warren, Michael S.; Dolag, Klaus

    2012-01-01

    We present a galaxy catalog simulator that converts N-body simulations with halo and subhalo catalogs into mock, multiband photometric catalogs. The simulator assigns galaxy properties to each subhalo in a way that reproduces the observed cluster galaxy halo occupation distribution, the radial and mass-dependent variation in fractions of blue galaxies, the luminosity functions in the cluster and the field, and the color-magnitude relation in clusters. Moreover, the evolution of these parameters is tuned to match existing observational constraints. Parameterizing an ensemble of cluster galaxy properties enables us to create mock catalogs with variations in those properties, which in turn allows us to quantify the sensitivity of cluster finding to current observational uncertainties in these properties. Field galaxies are sampled from existing multiband photometric surveys of similar depth. We present an application of the catalog simulator to characterize the selection function and contamination of a galaxy cluster finder that utilizes the cluster red sequence together with galaxy clustering on the sky. We estimate systematic uncertainties in the selection to be at the ≤15% level with current observational constraints on cluster galaxy populations and their evolution. We find the contamination in this cluster finder to be ∼35% to redshift z ∼ 0.6. In addition, we use the mock galaxy catalogs to test the optical mass indicator B gc and a red-sequence redshift estimator. We measure the intrinsic scatter of the B gc -mass relation to be approximately log normal with σ log10M ∼0.25 and we demonstrate photometric redshift accuracies for massive clusters at the ∼3% level out to z ∼ 0.7.

  12. Labeled factor IX kinetics in patients with hemophilia-B

    International Nuclear Information System (INIS)

    Smith, K.J.; Thompson, A.R.

    1981-01-01

    Labeled factor IX was infused five time into four patients with hemophilia-B. Ten-minute plasma recovery average 35% (SD +/- 2) and the mean T 1/2 beta-phase elimination was 23 hr (+/- 5). No alteration in the postinfusion 125I-factor-IX could be detected by radioautography of plasma samples run on polyacrylamide gels or on crossed-immunoelectrophoresis. Label was excreted into the urine as free 125I-iodide. Kinetics were similar when the labeled preparation was infused alone or with a commercial concentrate containing unlabeled factor IX. Infusion of factor IX in man is best described by a two-compartment open pharmacokinetic model where factor IX is distributed in a space larger than the plasma volume

  13. THE HAWAII SCUBA-2 LENSING CLUSTER SURVEY: NUMBER COUNTS AND SUBMILLIMETER FLUX RATIOS

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Li-Yen; Cowie, Lennox L.; Barger, Amy J. [Institute of Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Chen, Chian-Chou [Center for Extragalactic Astronomy, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Wang, Wei-Hao [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China)

    2016-09-20

    We present deep number counts at 450 and 850 μ m using the SCUBA-2 camera on the James Clerk Maxwell Telescope. We combine data for six lensing cluster fields and three blank fields to measure the counts over a wide flux range at each wavelength. Thanks to the lensing magnification, our measurements extend to fluxes fainter than 1 mJy and 0.2 mJy at 450 μ m and 850 μ m, respectively. Our combined data highly constrain the faint end of the number counts. Integrating our counts shows that the majority of the extragalactic background light (EBL) at each wavelength is contributed by faint sources with L {sub IR} < 10{sup 12} L {sub ⊙}, corresponding to luminous infrared galaxies (LIRGs) or normal galaxies. By comparing our result with the 500 μ m stacking of K -selected sources from the literature, we conclude that the K -selected LIRGs and normal galaxies still cannot fully account for the EBL that originates from sources with L {sub IR} < 10{sup 12} L {sub ⊙}. This suggests that many faint submillimeter galaxies may not be included in the UV star formation history. We also explore the submillimeter flux ratio between the two bands for our 450 μ m and 850 μ m selected sources. At 850 μ m, we find a clear relation between the flux ratio and the observed flux. This relation can be explained by a redshift evolution, where galaxies at higher redshifts have higher luminosities and star formation rates. In contrast, at 450 μ m, we do not see a clear relation between the flux ratio and the observed flux.

  14. Measuring human rights violations in a conflict-affected country: results from a nationwide cluster survey in Central African Republic

    Directory of Open Access Journals (Sweden)

    Roberts Les

    2011-03-01

    Full Text Available Abstract Background Measuring human rights violations is particularly challenging during or after armed conflict. A recent nationwide survey in the Central African Republic produced estimates of rates of grave violations against children and adults affected by armed conflict, using an approach known as the "Neighborhood Method". Methods In June and July, 2009, a random household survey was conducted based on population estimates from the 2003 national census. Clusters were assigned systematically proportional to population size. Respondents in randomly selected households were interviewed regarding incidents of killing, intentional injury, recruitment into armed groups, abduction, sexual abuse and rape between January 1, 2008 and the date of interview, occurring in their homes' and those of their three closest neighbors. Results Sixty of the selected 69 clusters were surveyed. In total, 599 women were interviewed about events in 2,370 households representing 13,669 persons. Estimates of annual rates of each violation occurring per 1000 people in each of two strata are provided for children between the ages of five and 17, adults 18 years of age and older and the entire population five years and older, along with a combined and weighted national rate. The national rates for children age five to 17 were estimated to be 0.98/1000/year (95% CI: 0.18 - 1.78 for recruitment, 2.56/1000/year (95% CI: 1.50 - 3.62 for abduction, 1.13/1000/year (95% CI: 0.33 - 1.93 for intentional injury, 10.72/1000 girls/year (95% CI: 7.40 - 14.04 for rape, and 4.80/1000 girls/year (95% CI: 2.61 - 6.00 for sexual abuse. No reports of any violation against a person under the age of five were recorded and there were no reports of rape or sexual abuse of males. No children were reported to have been killed during the recall period. Rape and abduction were the most frequently reported events. Conclusions The population-based figures greatly augment existing information on

  15. A survey on bio inspired meta heuristic based clustering protocols for wireless sensor networks

    Science.gov (United States)

    Datta, A.; Nandakumar, S.

    2017-11-01

    Recent studies have shown that utilizing a mobile sink to harvest and carry data from a Wireless Sensor Network (WSN) can improve network operational efficiency as well as maintain uniform energy consumption by the sensor nodes in the network. Due to Sink mobility, the path between two sensor nodes continuously changes and this has a profound effect on the operational longevity of the network and a need arises for a protocol which utilizes minimal resources in maintaining routes between the mobile sink and the sensor nodes. Swarm Intelligence based techniques inspired by the foraging behavior of ants, termites and honey bees can be artificially simulated and utilized to solve real wireless network problems. The author presents a brief survey on various bio inspired swarm intelligence based protocols used in routing data in wireless sensor networks while outlining their general principle and operation.

  16. Multiple vulnerabilities and maternal healthcare in Vietnam: findings from the Multiple Indicator Cluster Surveys, 2000, 2006, and 2011

    Directory of Open Access Journals (Sweden)

    Hoang Van Minh

    2016-02-01

    Full Text Available Background: Knowledge of the aggregate effects of multiple socioeconomic vulnerabilities is important for shedding light on the determinants of growing health inequalities and inequities in maternal healthcare. Objective: This paper describes patterns of inequity in maternal healthcare utilization and analyzes associations between inequity and multiple socioeconomic vulnerabilities among women in Vietnam. Design: This is a repeated cross-sectional study using data from the Vietnam Multiple Indicator Cluster Surveys 2000, 2006, and 2011. Two maternal healthcare indicators were selected: (1 skilled antenatal care and (2 skilled delivery care. Four types of socioeconomic vulnerabilities – low education, ethnic minority, poverty, and rural location – were assessed both as separate explanatory variables and as composite indicators (combinations of three and four vulnerabilities. Pairwise comparisons and adjusted odds ratios were used to assess socioeconomic inequities in maternal healthcare. Results: In all three surveys, there were increases across the survey years in both the proportions of women who received antenatal care by skilled staff (68.6% in 2000, 90.8% in 2006, and 93.7% in 2011 and the proportions of women who gave birth with assistance from skilled staff (69.9% in 2000, 87.7% in 2006, and 92.9% in 2011. The receipt of antenatal care by skilled staff and birth assistance from skilled health personnel were less common among vulnerable women, especially those with multiple vulnerabilities. Conclusions: Even though Vietnam has improved its coverage of maternal healthcare on average, policies should target maternal healthcare utilization among women with multiple socioeconomic vulnerabilities. Both multisectoral social policies and health policies are needed to tackle multiple vulnerabilities more effectively by identifying those who are poor, less educated, live in rural areas, and belong to ethnic minority groups.

  17. Sex Differences in Civilian Injury in Baghdad From 2003 to 2014: Results of a Randomized Household Cluster Survey.

    Science.gov (United States)

    Shaak, Kyle; Lafta, Riyadh; Stewart, Barclay T; Fowler, Thomas R; Al-Shatari, Sahar A Esa; Burnham, Gilbert; Cherewick, Megan; Wren, Sherry M; Groen, Reinou S; Kushner, Adam L

    2018-06-01

    To examine sex differences in injury mechanisms, injury-related death, injury-related disability, and associated financial consequences in Baghdad since the 2003 invasion of Iraq to inform prevention initiatives, health policy, and relief planning. Reliable estimates of injury burden among civilians during conflict are lacking, particularly among vulnerable subpopulations, such as women. A 2-stage, cluster randomized, community-based household survey was conducted in May 2014 to determine the civilian burden of injury in Baghdad since 2003. Households were surveyed regarding injury mechanisms, healthcare required, disability, deaths, connection to conflict, and resultant financial hardship. We surveyed 900 households (5148 individuals), reporting 553 injuries, 162 (29%) of which were injuries among women. The mean age of injury was higher among women compared with men (34 ± 21.3 vs 27 ± 16.5 years; P < 0.001). More women than men were injured while in the home [104 (64%) vs 82 (21%); P < 0.001]. Fewer women than men died from injuries [11 (6.8%) vs 77 (20%); P < 0.001]; however, women were more likely than men to live with reduced function [101 (63%) vs 192 (49%); P = 0.005]. Of intentional injuries, women had higher rates of injury by shell fragments (41% vs 26%); more men were injured by gunshots [76 (41%) vs 6 (17.6%); P = .011). Women experienced fewer injuries than men in postinvasion Baghdad, but were more likely to suffer disability after injury. Efforts to improve conditions for injured women should focus on mitigating financial and provisional hardships, providing counseling services, and ensuring access to rehabilitation services.

  18. The “UV-route” to Search for Blue Straggler Stars in Globular Clusters: First Results from the HST UV Legacy Survey

    Energy Technology Data Exchange (ETDEWEB)

    Raso, S.; Ferraro, F. R.; Lanzoni, B. [Department of Physics and Astronomy, University of Bologna, Viale Berti Pichat, 6/2, Bologna (Italy); Dalessandro, E. [INAF Osservatorio Astronomico di Bologna, Via Ranzani 1, Bologna (Italy); Nardiello, D. [Department of Physics and Astronomy Galileo Galilei, University of Padova, Vicolo dell’Osservatorio 3, I-35122 Padova (Italy); Bellini, A. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Vesperini, E. [Department of Astronomy, Indiana University, Bloomington, IN, 47401 (United States)

    2017-04-10

    We used data from the Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters to select the Blue Straggler Star (BSS) population in four intermediate/high density systems (namely NGC 2808, NGC 6388, NGC 6541, and NGC 7078) through a “UV-guided search.” This procedure consists of using the F275W images in each cluster to construct the master list of detected sources, and then force it to the images acquired in the other filters. Such an approach optimizes the detection of relatively hot stars and allows the detection of a complete sample of BSSs even in the central region of high-density clusters, because the light from the bright cool giants, which dominates the optical emission in old stellar systems, is sensibly reduced at UV wavelengths. Our UV-guided selections of BSSs have been compared to the samples obtained in previous, optical-driven surveys, clearly demonstrating the efficiency of the UV approach. In each cluster we also measured the parameter A {sup +}, defined as the area enclosed between the cumulative radial distribution of BSSs and that of a reference population, which traces the level of BSS central segregation and the level of dynamical evolution suffered by the system. The values measured for the four clusters studied in this paper nicely fall along the dynamical sequence recently presented for a sample of 25 clusters.

  19. Ares I-X Flight Test Philosophy

    Science.gov (United States)

    Davis, S. R.; Tuma, M. L.; Heitzman, K.

    2007-01-01

    In response to the Vision for Space Exploration, the National Aeronautics and Space Administration (NASA) has defined a new space exploration architecture to return humans to the Moon and prepare for human exploration of Mars. One of the first new developments will be the Ares I Crew Launch Vehicle (CLV), which will carry the Orion Crew Exploration Vehicle (CEV), into Low Earth Orbit (LEO) to support International Space Station (ISS) missions and, later, support lunar missions. As part of Ares I development, NASA will perform a series of Ares I flight tests. The tests will provide data that will inform the engineering and design process and verify the flight hardware and software. The data gained from the flight tests will be used to certify the new Ares/Orion vehicle for human space flight. The primary objectives of this first flight test (Ares I-X) are the following: Demonstrate control of a dynamically similar integrated Ares CLV/Orion CEV using Ares CLV ascent control algorithms; Perform an in-flight separation/staging event between an Ares I-similar First Stage and a representative Upper Stage; Demonstrate assembly and recovery of a new Ares CLV-like First Stage element at Kennedy Space Center (KSC); Demonstrate First Stage separation sequencing, and quantify First Stage atmospheric entry dynamics and parachute performance; and Characterize the magnitude of the integrated vehicle roll torque throughout the First Stage (powered) flight. This paper will provide an overview of the Ares I-X flight test process and details of the individual flight tests.

  20. Tissue factor-dependent activation of tritium-labeled factor IX and factor X in human plasma

    International Nuclear Information System (INIS)

    Morrison, S.A.; Jesty, J.

    1984-01-01

    A comparism was made of the tissue factor-dependent activation of tritium-labeled factor IX and factor X in a human plasma system and a study was made of the role of proteases known to stimulate factor VII activity. Plasma was defibrinated by heating and depleted of its factors IX and X by passing it through antibody columns. Addition of human brain thromboplastin, Ca2+, and purified 3H-labeled factor X to the plasma resulted, after a short lag, in burst-like activation of the factor X, measured as the release of radiolabeled activation peptide. The progress of activation was slowed by both heparin and a specific inhibitor of factor Xa but factor X activation could not be completely abolished by such inhibitors. In the case of 3H-factor IX activation, the rate also increased for approximately 3 min after addition of thromboplastin, but was not subsequently curtailed. A survey of proteases implicated as activators of factor VII in other settings showed that both factor Xa and factor IXa could accelerate the activation of factor IX. However, factor Xa was unique in obliterating activation when present at concentrations greater than approximately 1 nM. Heparin inhibited the tissue factor-dependent activation of factor IX almost completely, apparently through the effect of antithrombin on the feedback reactions of factors Xa and IXa on factor VII. These results suggest that a very tight, biphasic control of factor VII activity exists in human plasma, which is modulated mainly by factor Xa. At saturation of factor VIIa/tissue factor, factor IX activation was significantly more rapid than was previously found in bovine plasma under similar conditions. The activation of factor X at saturation was slightly more rapid than in bovine plasma, despite the presence of heparin

  1. IBM PC/IX operating system evaluation plan

    Science.gov (United States)

    Dominick, Wayne D. (Editor); Granier, Martin; Hall, Philip P.; Triantafyllopoulos, Spiros

    1984-01-01

    An evaluation plan for the IBM PC/IX Operating System designed for IBM PC/XT computers is discussed. The evaluation plan covers the areas of performance measurement and evaluation, software facilities available, man-machine interface considerations, networking, and the suitability of PC/IX as a development environment within the University of Southwestern Louisiana NASA PC Research and Development project. In order to compare and evaluate the PC/IX system, comparisons with other available UNIX-based systems are also included.

  2. Electrophysiology of Cranial Nerve Testing: Cranial Nerves IX and X.

    Science.gov (United States)

    Martinez, Alberto R M; Martins, Melina P; Moreira, Ana Lucila; Martins, Carlos R; Kimaid, Paulo A T; França, Marcondes C

    2018-01-01

    The cranial nerves IX and X emerge from medulla oblongata and have motor, sensory, and parasympathetic functions. Some of these are amenable to neurophysiological assessment. It is often hard to separate the individual contribution of each nerve; in fact, some of the techniques are indeed a composite functional measure of both nerves. The main methods are the evaluation of the swallowing function (combined IX and X), laryngeal electromyogram (predominant motor vagal function), and heart rate variability (predominant parasympathetic vagal function). This review describes, therefore, the techniques that best evaluate the major symptoms presented in IX and X cranial nerve disturbance: dysphagia, dysphonia, and autonomic parasympathetic dysfunction.

  3. The Arecibo Galaxy Environment Survey IX: the isolated galaxy sample

    Czech Academy of Sciences Publication Activity Database

    Minchin, R.F.; Auld, R.; Davies, J.I.; Karachentsev, I.D.; Keenan, O.; Momjian, E.; Rodriguez, R.; Taber, T.; Taylor, Rhys

    2016-01-01

    Roč. 455, č. 4 (2016), s. 3430-3435 ISSN 0035-8711 R&D Projects: GA MŠk LG14013; GA ČR GAP209/12/1795 Institutional support: RVO:67985815 Keywords : individual galaxies NGC 1156 * individual galaxies NGC 5523 * individual galaxies UGC 2082 Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.961, year: 2016

  4. Data Clustering

    Science.gov (United States)

    Wagstaff, Kiri L.

    2012-03-01

    On obtaining a new data set, the researcher is immediately faced with the challenge of obtaining a high-level understanding from the observations. What does a typical item look like? What are the dominant trends? How many distinct groups are included in the data set, and how is each one characterized? Which observable values are common, and which rarely occur? Which items stand out as anomalies or outliers from the rest of the data? This challenge is exacerbated by the steady growth in data set size [11] as new instruments push into new frontiers of parameter space, via improvements in temporal, spatial, and spectral resolution, or by the desire to "fuse" observations from different modalities and instruments into a larger-picture understanding of the same underlying phenomenon. Data clustering algorithms provide a variety of solutions for this task. They can generate summaries, locate outliers, compress data, identify dense or sparse regions of feature space, and build data models. It is useful to note up front that "clusters" in this context refer to groups of items within some descriptive feature space, not (necessarily) to "galaxy clusters" which are dense regions in physical space. The goal of this chapter is to survey a variety of data clustering methods, with an eye toward their applicability to astronomical data analysis. In addition to improving the individual researcher’s understanding of a given data set, clustering has led directly to scientific advances, such as the discovery of new subclasses of stars [14] and gamma-ray bursts (GRBs) [38]. All clustering algorithms seek to identify groups within a data set that reflect some observed, quantifiable structure. Clustering is traditionally an unsupervised approach to data analysis, in the sense that it operates without any direct guidance about which items should be assigned to which clusters. There has been a recent trend in the clustering literature toward supporting semisupervised or constrained

  5. Survey of e-learning implementation and faculty support strategies in a cluster of mid-European medical schools.

    Science.gov (United States)

    Back, David Alexander; Behringer, Florian; Harms, Tina; Plener, Joachim; Sostmann, Kai; Peters, Harm

    2015-09-03

    The use of electronic learning formats (e-learning) in medical education is reported mainly from individual specialty perspectives. In this study, we analyzed the implementation level of e-learning formats and the institutional support structures and strategies at an institutional level in a cluster of mid-European medical schools. A 49-item online questionnaire was send to 48 medical schools in Austria, Germany and Switzerland using SurveyMonkey®. Data were collected between February and September of 2013 and analyzed using quantities, statistical and qualitative means. The response rate was 71 %. All schools had implemented e-learning, but mainly as an optional supplement to the curriculum. E-learning involved a wide range of formats across all disciplines. Online learning platforms were used by 97 % of the schools. Full-time e-learning staff was employed by 50 %, and these had a positive and significant effect on the presence of e-learning in the corresponding medical schools. In addition, 81 % offered training programs and qualifications for their teachers and 76 % awarded performance-oriented benefits, with 17 % giving these for e-learning tasks. Realization of e-learning offers was rewarded by 33 %, with 27 % recognizing this as part of the teaching load. 97 % would use curriculum-compatible e-learning tools produced by other faculties. While all participating medical schools used e-learning concepts, this survey revealed also a reasonable support by institutional infrastructure and the importance of staff for the implementation level of e-learning offerings. However, data showed some potential for increasing tangible incentives to motivate teachers to engage in further use of e-learning. Furthermore, the use of individual tools and the distribution of e-learning presentations in various disciplines were quite inhomogeneous. The willingness of the medical schools to cooperate should be capitalized for the future, especially concerning the provision of e

  6. Design of the South East Asian Nutrition Survey (SEANUTS): a four-country multistage cluster design study.

    Science.gov (United States)

    Schaafsma, Anne; Deurenberg, Paul; Calame, Wim; van den Heuvel, Ellen G H M; van Beusekom, Christien; Hautvast, Jo; Sandjaja; Bee Koon, Poh; Rojroongwasinkul, Nipa; Le Nguyen, Bao Khanh; Parikh, Panam; Khouw, Ilse

    2013-09-01

    Nutrition is a well-known factor in the growth, health and development of children. It is also acknowledged that worldwide many people have dietary imbalances resulting in over- or undernutrition. In 2009, the multinational food company FrieslandCampina initiated the South East Asian Nutrition Survey (SEANUTS), a combination of surveys carried out in Indonesia, Malaysia, Thailand and Vietnam, to get a better insight into these imbalances. The present study describes the general study design and methodology, as well as some problems and pitfalls encountered. In each of these countries, participants in the age range of 0·5-12 years were recruited according to a multistage cluster randomised or stratified random sampling methodology. Field teams took care of recruitment and data collection. For the health status of children, growth and body composition, physical activity, bone density, and development and cognition were measured. For nutrition, food intake and food habits were assessed by questionnaires, whereas in subpopulations blood and urine samples were collected to measure the biochemical status parameters of Fe, vitamins A and D, and DHA. In Thailand, the researchers additionally studied the lipid profile in blood, whereas in Indonesia iodine excretion in urine was analysed. Biochemical data were analysed in certified laboratories. Study protocols and methodology were aligned where practically possible. In December 2011, data collection was finalised. In total, 16,744 children participated in the present study. Information that will be very relevant for formulating nutritional health policies, as well as for designing innovative food and nutrition research and development programmes, has become available.

  7. Development and enrolee satisfaction with basic medical insurance in China: A systematic review and stratified cluster sampling survey.

    Science.gov (United States)

    Jing, Limei; Chen, Ru; Jing, Lisa; Qiao, Yun; Lou, Jiquan; Xu, Jing; Wang, Junwei; Chen, Wen; Sun, Xiaoming

    2017-07-01

    Basic Medical Insurance (BMI) has changed remarkably over time in China because of health reforms that aim to achieve universal coverage and better health care with adequate efforts by increasing subsidies, reimbursement, and benefits. In this paper, we present the development of BMI, including financing and operation, with a systematic review. Meanwhile, Pudong New Area in Shanghai was chosen as a typical BMI sample for its coverage and management; a stratified cluster sampling survey together with an ordinary logistic regression model was used for the analysis. Enrolee satisfaction and the factors associated with enrolee satisfaction with BMI were analysed. We found that the reenrolling rate superficially improved the BMI coverage and nearly achieved universal coverage. However, BMI funds still faced dual contradictions of fund deficit and insured under compensation, and a long-term strategy is needed to realize the integration of BMI schemes with more homogeneous coverage and benefits. Moreover, Urban Resident Basic Medical Insurance participants reported a higher rate of dissatisfaction than other participants. The key predictors of the enrolees' satisfaction were awareness of the premium and compensation, affordability of out-of-pocket costs, and the proportion of reimbursement. These results highlight the importance that the Chinese government takes measures, such as strengthening BMI fund management, exploring mixed payment methods, and regulating sequential medical orders, to develop an integrated medical insurance system of universal coverage and vertical equity while simultaneously improving enrolee satisfaction. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Determinants of child maltreatment in Nepal: Results from the 2014 Nepal multiple indicator cluster survey (the 2014 NMICS).

    Science.gov (United States)

    Atteraya, Madhu Sudhan; Ebrahim, Nasser B; Gnawali, Shreejana

    2018-02-01

    We examined the prevalence of child maltreatment as measured by the level of physical (moderate to severe) and emotional abuse and child labor, and the associated household level determinants of child maltreatment in Nepal. We used a nationally representative data set from the fifth round of the Nepal Multiple Indicator Cluster Survey (the 2014 NMICS). The main independent variables were household level characteristics. Dependent variables included child experience of moderate to severe physical abuse, emotional abuse, and child labor (domestic work and economic activities). Bivariate analyses and logistic regressions were used to examine the associations between independent and dependent variables. The results showed that nearly half of the children (49.8%) had experienced moderate physical abuse, 21.5% experienced severe physical abuse, and 77.3% experienced emotional abuse. About 27% of the children had engaged in domestic work and 46.7% in various economic activities. At bivariate level, educational level of household's head and household wealth status had shown significant statistical association with child maltreatment (pchild labor. In general, child maltreatment is a neglected social issue in Nepal and the high rates of child maltreatment calls for mass awareness programs focusing on parents, and involving all stakeholders including governments, local, and international organizations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. The ESO Nearby Abell Cluster Survey. VI. Spatial distribution and kinematics of early- and late-type galaxies

    Science.gov (United States)

    de Theije, P. A. M.; Katgert, P.

    1999-01-01

    Analysis of the data obtained in the ESO Nearby Abell Cluster Survey (ENACS) has shown that the space distribution and kinematics of galaxies with detectable emission lines in their spectra differ significantly from those of galaxies without emission lines. This result, and details of the kinematics, were considered as support for the idea that at least the spirals with emission lines are on orbits that are not isotropic. This might indicate that this subset of late-type galaxies either has `first approach'-orbits towards the dense core of their respective clusters, or has orbits that `avoid' the core. The galaxies with emission lines are essentially all late-type galaxies. On the other hand, the emission-line galaxies represent only about a third of the late-type galaxies, the majority of which do not show detectable emission lines. The galaxies without emission lines are therefore a mix of early- and late-type galaxies. In this paper we attempt to separate early- and late-type galaxies, and we study possible differences in distribution and kinematics of the two galaxy classes. For only about 10% of the galaxies in the ENACS, the morphology is known from imaging. Here, we describe our classification on the basis of the ENACS spectrum. The significant information in each spectrum is compressed into 15 Principal Components, which are used as input for an Artificial Neural Network. The latter is `trained' with 150 of the 270 galaxies for which a morphological type is available from Dressler, and subsequently used to classify each galaxy. This yields a classification for two-thirds of the ENACS galaxies. The Artificial Neural Network has two output classes: early-type (E+S0) and late-type (S+I) galaxies. We do not distinguish E and S0 galaxies, because these cannot be separated very robustly on the basis of the spectrum. The success rate of the classification is estimated from the sample of 120 galaxies with Dressler morphologies which were not used to train the ANN

  10. Massive open star clusters using the VVV survey IV. WR 62-2, a new very massive star in the core of the VVV CL041 cluster

    Czech Academy of Sciences Publication Activity Database

    Chene, A.-N.; Alegria, S.R.; Borissova, J.; O'Leary, E.; Martins, F.; Hervé, Anthony; Kuhn, M.; Kurtev, R.; Consuelo Amigo Fuentes, P.; Bonatto, C.; Minniti, D.

    2015-01-01

    Roč. 584, December (2015), A31/1-A31/8 ISSN 0004-6361 R&D Projects: GA ČR(CZ) GA14-02385S Institutional support: RVO:67985815 Keywords : open clusters and associations * VVV CL041 * massive star s Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.378, year: 2014

  11. [High risk groups in health behavior defined by clustering of smoking, alcohol, and exercise habits: National Heath and Nutrition Examination Survey].

    Science.gov (United States)

    Kang, Kiwon; Sung, Joohon; Kim, Chang Yup

    2010-01-01

    We investigated the clustering of selected lifestyle factors (cigarette smoking, heavy alcohol consumption, lack of physical exercise) and identified the population characteristics associated with increasing lifestyle risks. Data on lifestyle risk factors, sociodemographic characteristics, and history of chronic diseases were obtained from 7,694 individuals >/=20 years of age who participated in the 2005 Korea National Health and Nutrition Examination Survey (KNHANES). Clustering of lifestyle risks involved the observed prevalence of multiple risks and those expected from marginal exposure prevalence of the three selected risk factors. Prevalence odds ratio was adopted as a measurement of clustering. Multiple correspondence analysis, Kendall tau correlation, Man-Whitney analysis, and ordinal logistic regression analysis were conducted to identify variables increasing lifestyle risks. In both men and women, increased lifestyle risks were associated with clustering of: (1) cigarette smoking and excessive alcohol consumption, and (2) smoking, excessive alcohol consumption, and lack of physical exercise. Patterns of clustering for physical exercise were different from those for cigarette smoking and alcohol consumption. The increased unhealthy clustering was found among men 20-64 years of age with mild or moderate stress, and among women 35-49 years of age who were never-married, with mild stress, and increased body mass index (>30 kg/m(2)). Addressing a lack of physical exercise considering individual characteristics including gender, age, employment activity, and stress levels should be a focus of health promotion efforts.

  12. Weak-lensing mass calibration of the Atacama Cosmology Telescope equatorial Sunyaev-Zeldovich cluster sample with the Canada-France-Hawaii telescope stripe 82 survey

    Energy Technology Data Exchange (ETDEWEB)

    Battaglia, N.; Miyatake, H.; Hasselfield, M.; Calabrese, E.; Ferrara, S.; Hložek, R. [Dept. of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Leauthaud, A. [Kavli IPMU (WPI), UTIAS, The University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Gralla, M.B.; Crichton, D. [Dept. of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Allison, R.; Dunkley, J. [Dept. of Astrophysics, University of Oxford, Oxford OX1 3RH (United Kingdom); Bond, J.R. [Canadian Institute for Theoretical Astrophysics, Toronto, ON M5S 3H8 (Canada); Devlin, M.J. [Dept. of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Dünner, R. [Dept. de Astronomía y Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Santiago (Chile); Erben, T. [Argelander-Institut für Astronomie, University of Bonn, 53121 Bonn (Germany); Halpern, M.; Hincks, A.D. [Dept. of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z4 (Canada); Hilton, M. [Astrophysics and Cosmology Research Unit, School of Mathematical, Statistics and Computer Science, University of KwaZulu-Natal, Durban, 4041 (South Africa); Hill, J.C. [Dept. of Astronomy, Columbia University, New York, NY 10027 (United States); Huffenberger, K.M., E-mail: nbatta@astro.princeton.edu [Dept. of Physics, Florida State University, Tallahassee, FL 32306 (United States); and others

    2016-08-01

    Mass calibration uncertainty is the largest systematic effect for using clusters of galaxies to constrain cosmological parameters. We present weak lensing mass measurements from the Canada-France-Hawaii Telescope Stripe 82 Survey for galaxy clusters selected through their high signal-to-noise thermal Sunyaev-Zeldovich (tSZ) signal measured with the Atacama Cosmology Telescope (ACT). For a sample of 9 ACT clusters with a tSZ signal-to-noise greater than five the average weak lensing mass is (4.8±0.8) ×10{sup 14} M{sub ⊙}, consistent with the tSZ mass estimate of (4.70±1.0) ×10{sup 14} M{sub ⊙} which assumes a universal pressure profile for the cluster gas. Our results are consistent with previous weak-lensing measurements of tSZ-detected clusters from the Planck satellite. When comparing our results, we estimate the Eddington bias correction for the sample intersection of Planck and weak-lensing clusters which was previously excluded.

  13. Weak-lensing mass calibration of the Atacama Cosmology Telescope equatorial Sunyaev-Zeldovich cluster sample with the Canada-France-Hawaii telescope stripe 82 survey

    International Nuclear Information System (INIS)

    Battaglia, N.; Miyatake, H.; Hasselfield, M.; Calabrese, E.; Ferrara, S.; Hložek, R.; Leauthaud, A.; Gralla, M.B.; Crichton, D.; Allison, R.; Dunkley, J.; Bond, J.R.; Devlin, M.J.; Dünner, R.; Erben, T.; Halpern, M.; Hincks, A.D.; Hilton, M.; Hill, J.C.; Huffenberger, K.M.

    2016-01-01

    Mass calibration uncertainty is the largest systematic effect for using clusters of galaxies to constrain cosmological parameters. We present weak lensing mass measurements from the Canada-France-Hawaii Telescope Stripe 82 Survey for galaxy clusters selected through their high signal-to-noise thermal Sunyaev-Zeldovich (tSZ) signal measured with the Atacama Cosmology Telescope (ACT). For a sample of 9 ACT clusters with a tSZ signal-to-noise greater than five the average weak lensing mass is (4.8±0.8) ×10 14 M ⊙ , consistent with the tSZ mass estimate of (4.70±1.0) ×10 14 M ⊙ which assumes a universal pressure profile for the cluster gas. Our results are consistent with previous weak-lensing measurements of tSZ-detected clusters from the Planck satellite. When comparing our results, we estimate the Eddington bias correction for the sample intersection of Planck and weak-lensing clusters which was previously excluded.

  14. Legal Forum: Title IX: Does It Apply to Employees?

    Science.gov (United States)

    McCarthy, Martha

    1981-01-01

    Briefly reviews a number of Federal court cases that have dealt with Title IX, considering the issue of whether the 1974 regulations prohibiting sex discrimination in employment practices accurately reflect the intent of the 1972 law. (GC)

  15. Protoporphyrin IX-induced structural and functional changes in ...

    Indian Academy of Sciences (India)

    Unknown

    Drug-protein binding; haemoglobin; myoglobin; protoporphyrin IX; red blood cells ... haemoglobin and myoglobin are potentiated by the protein-porphyrin complexation. Possible ...... 1985 Uptake and delivery of the respiratory gases; in Best ...

  16. The Gaia-ESO Survey and CSI 2264: Substructures, disks, and sequential star formation in the young open cluster NGC 2264

    Science.gov (United States)

    Venuti, L.; Prisinzano, L.; Sacco, G. G.; Flaccomio, E.; Bonito, R.; Damiani, F.; Micela, G.; Guarcello, M. G.; Randich, S.; Stauffer, J. R.; Cody, A. M.; Jeffries, R. D.; Alencar, S. H. P.; Alfaro, E. J.; Lanzafame, A. C.; Pancino, E.; Bayo, A.; Carraro, G.; Costado, M. T.; Frasca, A.; Jofré, P.; Morbidelli, L.; Sousa, S. G.; Zaggia, S.

    2018-01-01

    Context. Reconstructing the structure and history of young clusters is pivotal to understanding the mechanisms and timescales of early stellar evolution and planet formation. Recent studies suggest that star clusters often exhibit a hierarchical structure, possibly resulting from several star formation episodes occurring sequentially rather than a monolithic cloud collapse. Aims: We aim to explore the structure of the open cluster and star-forming region NGC 2264 ( 3 Myr), which is one of the youngest, richest and most accessible star clusters in the local spiral arm of our Galaxy; we link the spatial distribution of cluster members to other stellar properties such as age and evolutionary stage to probe the star formation history within the region. Methods: We combined spectroscopic data obtained as part of the Gaia-ESO Survey (GES) with multi-wavelength photometric data from the Coordinated Synoptic Investigation of NGC 2264 (CSI 2264) campaign. We examined a sample of 655 cluster members, with masses between 0.2 and 1.8 M⊙ and including both disk-bearing and disk-free young stars. We used Teff estimates from GES and g,r,i photometry from CSI 2264 to derive individual extinction and stellar parameters. Results: We find a significant age spread of 4-5 Myr among cluster members. Disk-bearing objects are statistically associated with younger isochronal ages than disk-free sources. The cluster has a hierarchical structure, with two main blocks along its latitudinal extension. The northern half develops around the O-type binary star S Mon; the southern half, close to the tip of the Cone Nebula, contains the most embedded regions of NGC 2264, populated mainly by objects with disks and ongoing accretion. The median ages of objects at different locations within the cluster, and the spatial distribution of disked and non-disked sources, suggest that star formation began in the north of the cluster, over 5 Myr ago, and was ignited in its southern region a few Myr later

  17. THE XMM CLUSTER SURVEY: GALAXY MORPHOLOGIES AND THE COLOR-MAGNITUDE RELATION IN XMMXCS J2215.9 - 1738 AT z = 1.46

    International Nuclear Information System (INIS)

    Hilton, Matt; Stanford, S. Adam; Stott, John P.; Collins, Chris A.; Hoyle, Ben; Nichol, Robert C.; Davidson, Michael; Mann, Robert G.; Hosmer, Mark; Liddle, Andrew R.; Lloyd-Davies, Ed; Mehrtens, Nicola; Romer, A. Kathy; Sabirli, Kivanc; Sahlen, Martin; Kay, Scott T.; Miller, Christopher J.; Viana, Pedro T. P.; West, Michael J.; Barbary, Kyle

    2009-01-01

    We present a study of the morphological fractions and color-magnitude relation (CMR) in the most distant X-ray selected galaxy cluster currently known, XMMXCS J2215.9 - 1738 at z = 1.46, using a combination of optical imaging data obtained with the Hubble Space Telescope Advanced Camera for Surveys, and infrared data from the Multi-Object Infrared Camera and Spectrograph, mounted on the 8.2 m Subaru telescope. We find that the morphological mix of the cluster galaxy population is similar to clusters at z ∼ 1. Within the central 0.5 Mpc, approximately ∼62% of the galaxies identified as likely cluster members are ellipticals or S0s; and ∼38% are spirals or irregulars. Therefore, early-type galaxies were already entrenched as the dominant galaxy population in at least some clusters approximately ∼4.5 Gyr after the big bang. We measure the CMRs for the early-type galaxies, finding that the slope in the z 850 -J relation is consistent with that measured in the Coma cluster, some ∼9 Gyr earlier, although the uncertainty is large. In contrast, the measured intrinsic scatter about the CMR is more than three times the value measured in Coma, after conversion to rest-frame U - V. From comparison with stellar population synthesis models, the intrinsic scatter measurements imply mean luminosity-weighted ages for the early-type galaxies in J2215.9 - 1738 of ∼3 Gyr, corresponding to the major epoch of star formation coming to an end at z f ∼ 3-5. We find that the cluster exhibits evidence of the 'downsizing' phenomenon: the fraction of faint cluster members on the red sequence expressed using the Dwarf-to-Giant Ratio (DGR) is 0.32 ± 0.18 within a radius of 0.5R 200 . This is consistent with extrapolation of the redshift evolution of the DGR seen in cluster samples at z 1 clusters, we find a lack of very bright galaxies within the cluster.

  18. Survey of facility and management characteristics of large, Upper Midwest dairy herds clustered by Dairy Herd Improvement records.

    Science.gov (United States)

    Brotzman, R L; Döpfer, D; Foy, M R; Hess, J P; Nordlund, K V; Bennett, T B; Cook, N B

    2015-11-01

    A survey of management practices was conducted to investigate potential associations with groupings of herds formed by cluster analysis (CA) of Dairy Herd Improvement (DHI) data of 557 Upper Midwest herds of 200 cows or greater. Differences in herd management practices were identified between the groups, despite underlying similarities; for example, freestall housing and milking in a parlor. Group 6 comprised larger herds with a high proportion of primiparous cows and most frequently utilized practices promoting increased production [e.g., 84.4% used recombinant bovine somatotropin (rbST)], decreased lameness (e.g., 96.9% used routine hoof trimming for cows), and improved efficiency in reproduction [e.g., 93.8% synchronized the first breeding in cows (SYNCH)] and labor (e.g., mean ± SD, 67 ± 19 cows per 50-h per week full-time equivalent worker). Group 1 had the best mean DHI performances and followed most closely group 6 for the rate of adoption of intensive management practices while tending to outperform group 6 despite a generally smaller mean herd size (e.g., 42.3 ± 3.6 kg vs. 39.9 ± 3.6 kg of energy-corrected milk production; 608 ± 352 cows vs. 1,716 ± 1,405 cows). Group 2 were smaller herds with relatively high levels of performance that used less intensive management (e.g., 100% milked twice daily) and less technology (33.3 vs. 73.0% of group 1 used rbST). Group 4 were smaller but poorer-performing herds with low turnover and least frequently used intensive management practices (e.g., 39.1% SYNCH; 30.4% allowed mature, high-producing cows access to pasture). Group 5 used modern technologies and practices associated with improved production, yet had the least desirable mean DHI performance of all 6 groups. This group had the lowest proportion of deep loose-bedded stalls (only 52.2% used sand bedding) and the highest proportion (34.8%) of herds not using routine hoof trimming. The survey of group 3 herds did not reveal strong trends in management. The

  19. THE HUBBLE SPACE TELESCOPE UV LEGACY SURVEY OF GALACTIC GLOBULAR CLUSTERS. III. A QUINTUPLE STELLAR POPULATION IN NGC 2808

    International Nuclear Information System (INIS)

    Milone, A. P.; Marino, A. F.; Jerjen, H.; Piotto, G.; Renzini, A.; Bedin, L. R.; Anderson, J.; Bellini, A.; Cassisi, S.; Pietrinferni, A.; D’Antona, F.; Ventura, P.

    2015-01-01

    In this study we present the first results from multi-wavelength Hubble Space Telescope (HST) observations of the Galactic globular cluster (GC) NGC 2808 as an extension of the Hubble Space Telescope UV Legacy Survey of Galactic GCs (GO-13297 and previous proprietary and HST archive data). Our analysis allowed us to disclose a multiple-stellar-population phenomenon in NGC 2808 even more complex than previously thought. We have separated at least five different populations along the main sequence and the red giant branch (RGB), which we name A, B, C, D, and E (though an even finer subdivision may be suggested by the data). We identified the RGB bump in four out of the five RGBs. To explore the origin of this complex color–magnitude diagram, we have combined our multi-wavelength HST photometry with synthetic spectra, generated by assuming different chemical compositions. The comparison of observed colors with synthetic spectra suggests that the five stellar populations have different contents of light elements and helium. Specifically, if we assume that NGC 2808 is homogeneous in [Fe/H] (as suggested by spectroscopy for Populations B, C, D, E, but lacking for Population A) and that population A has a primordial helium abundance, we find that populations B, C, D, E are enhanced in helium by ΔY ∼ 0.03, 0.03, 0.08, 0.13, respectively. We obtain similar results by comparing the magnitude of the RGB bumps with models. Planned spectroscopic observations will test whether Population A also has the same metallicity, or whether its photometric differences with Population B can be ascribed to small [Fe/H] and [O/H] differences rather than to helium

  20. Trends in socioeconomic inequalities in child malnutrition in Vietnam: findings from the Multiple Indicator Cluster Surveys, 2000–2011

    Science.gov (United States)

    Kien, Vu Duy; Lee, Hwa-Young; Nam, You-Seon; Oh, Juhwan; Giang, Kim Bao; Van Minh, Hoang

    2016-01-01

    Background Child malnutrition is not only a major contributor to child mortality and morbidity, but it can also determine socioeconomic status in adult life. The rate of under-five child malnutrition in Vietnam has significantly decreased, but associated inequality issues still need attention. Objective This study aims to explore trends, contributing factors, and changes in inequalities for under-five child malnutrition in Vietnam between 2000 and 2011. Design Data were drawn from the Viet Nam Multiple Indicator Cluster Survey for the years 2000 and 2011. The dependent variables used for the study were stunting, underweight, and wasting of under-five children. The concentration index was calculated to see the magnitude of child malnutrition, and the inequality was decomposed to understand the contributions of determinants to child malnutrition. The total differential decomposition was used to identify and explore factors contributing to changes in child malnutrition inequalities. Results Inequality in child malnutrition increased between 2000 and 2011, even though the overall rate declined. Most of the inequality in malnutrition was due to ethnicity and socioeconomic status. The total differential decomposition showed that the biggest and second biggest contributors to the changes in underweight inequalities were age and socioeconomic status, respectively. Socioeconomic status was the largest contributor to inequalities in stunting. Conclusions Although the overall level of child malnutrition was improved in Vietnam, there were significant differences in under-five child malnutrition that favored those who were more advantaged in socioeconomic terms. The impact of socioeconomic inequalities in child malnutrition has increased over time. Multifaceted approaches, connecting several relevant ministries and sectors, may be necessary to reduce inequalities in childhood malnutrition. PMID:26950558

  1. Effect of child marriage on girls' school dropout in Nepal: Analysis of data from the Multiple Indicator Cluster Survey 2014.

    Directory of Open Access Journals (Sweden)

    Kazutaka Sekine

    Full Text Available School dropout and child marriage are interrelated outcomes that have an enormous impact on adolescent girls. However, the literature reveals gaps in the empirical evidence on the link between child marriage and the dropout of girls from school. This study identifies the 'tipping point' school grades in Nepal when the risk of dropout due to marriage is highest, measures the effect of child marriage on girls' school dropout rates, and assesses associated risk factors. Weighted percentages were calculated to examine the grades at highest risk and the distribution of reasons for discontinuing school. Using the Nepal Multiple Indicator Cluster Survey (MICS 2014 data, we estimated the effect of marriage on school attendance and dropout among girls aged 15-17 by constructing logistic regression models. A multivariate logistic regression model was used to assess risk factors of school dropout due to child marriage. It was found that early marriage is the most common reason given for leaving school. Overall, the risk of school dropout due to marriage heightens after girls complete the fifth or sixth grade. The risk of girls' dropping out peaks in the seventh and eighth grades and remains noteworthy in the ninth and tenth grades. Married girls in Nepal are 10 times more likely to drop out than their unmarried peers. Little or no education of the household head, belonging to the Kirat religion, and membership of a traditionally disadvantaged social class each elevate the risk of school dropout due to early marriage. The findings underscore the need to delay girl's marriage so as to reduce girls' school dropout in Nepal. School-based programmes aimed at preventing child marriage should target girls from the fifth grade because they are at increased risk of dropping out, as well as prioritizing girls from disadvantaged groups.

  2. Prevalence and Risk Factors of Dengue Infection in Khanh Hoa Province, Viet Nam: A Stratified Cluster Sampling Survey.

    Science.gov (United States)

    Mai, Vien Quang; Mai, Trịnh Thị Xuan; Tam, Ngo Le Minh; Nghia, Le Trung; Komada, Kenichi; Murakami, Hitoshi

    2018-05-19

    Dengue is a clinically important arthropod-borne viral disease with increasing global incidence. Here we aimed to estimate the prevalence of dengue infections in Khanh Hoa Province, central Viet Nam, and to identify risk factors for infection. We performed a stratified cluster sampling survey including residents of 3-60 years of age in Nha Trang City, Ninh Hoa District and Dien Khanh District, Khanh Hoa Province, in October 2011. Immunoglobulin G (IgG) and immunoglobulin M (IgM) against dengue were analyzed using a rapid test kit. Participants completed a questionnaire exploring clinical dengue incidence, socio-economic status, and individual behavior. A household checklist was used to examine environment, mosquito larvae presence, and exposure to public health interventions. IgG positivity was 20.5% (urban, 16.3%; rural, 23.0%), IgM positivity was 6.7% (urban, 6.4%; rural, 6.9%), and incidence of clinically compatible dengue during the prior 3 months was 2.8 per 1,000 persons (urban, 1.7; rural, 3.4). For IgG positivity, the adjusted odds ratio (AOR) was 2.68 (95% confidence interval [CI], 1.24-5.81) for mosquito larvae presence in water pooled in old tires and was 3.09 (95% CI, 1.75-5.46) for proximity to a densely inhabited area. For IgM positivity, the AOR was 3.06 (95% CI, 1.50-6.23) for proximity to a densely inhabited area. Our results indicated rural penetration of dengue infections. Control measures should target densely inhabited areas, and may include clean-up of discarded tires and water-collecting waste.

  3. Trends in socioeconomic inequalities in child malnutrition in Vietnam: findings from the Multiple Indicator Cluster Surveys, 2000-2011.

    Science.gov (United States)

    Kien, Vu Duy; Lee, Hwa-Young; Nam, You-Seon; Oh, Juhwan; Giang, Kim Bao; Van Minh, Hoang

    2016-01-01

    Child malnutrition is not only a major contributor to child mortality and morbidity, but it can also determine socioeconomic status in adult life. The rate of under-five child malnutrition in Vietnam has significantly decreased, but associated inequality issues still need attention. This study aims to explore trends, contributing factors, and changes in inequalities for under-five child malnutrition in Vietnam between 2000 and 2011. Data were drawn from the Viet Nam Multiple Indicator Cluster Survey for the years 2000 and 2011. The dependent variables used for the study were stunting, underweight, and wasting of under-five children. The concentration index was calculated to see the magnitude of child malnutrition, and the inequality was decomposed to understand the contributions of determinants to child malnutrition. The total differential decomposition was used to identify and explore factors contributing to changes in child malnutrition inequalities. Inequality in child malnutrition increased between 2000 and 2011, even though the overall rate declined. Most of the inequality in malnutrition was due to ethnicity and socioeconomic status. The total differential decomposition showed that the biggest and second biggest contributors to the changes in underweight inequalities were age and socioeconomic status, respectively. Socioeconomic status was the largest contributor to inequalities in stunting. Although the overall level of child malnutrition was improved in Vietnam, there were significant differences in under-five child malnutrition that favored those who were more advantaged in socioeconomic terms. The impact of socioeconomic inequalities in child malnutrition has increased over time. Multifaceted approaches, connecting several relevant ministries and sectors, may be necessary to reduce inequalities in childhood malnutrition.

  4. The Atacama Cosmology Telescope: Sunyaev-Zel'dovich-Selected Galaxy Clusters AT 148 GHz in the 2008 Survey

    Science.gov (United States)

    Marriage, Tobias A.; Acquaviva, Viviana; Ade, Peter A. R.; Aguirre, Paula; Amiri, Mandana; Appel, John William; Barrientos, L. Felipe; Battistelli, Elia S.; Bond, J. Richard; Brown, Ben; hide

    2011-01-01

    We report on 23 clusters detected blindly as Sunyaev-Zel'dovich (SZ) decrements in a 148 GHz, 455 deg (exp 2) map of the southern sky made with data from the Atacama Cosmology Telescope 2008 observing season. All SZ detections announced in this work have confirmed optical counterparts. Ten of the clusters are new discoveries. One newly discovered cluster, ACT-CL 10102-4915, with a redshift of 0.75 (photometric), has an SZ decrement comparable to the most massive systems at lower redshifts. Simulations of the cluster recovery method reproduce the sample purity measured by optical follow-up. In particular, for clusters detected with a signal-to-noise ratio greater than six, simulations are consistent with optical follow-up that demonstrated this subsample is 100% pure, The simulations further imply that the total sample is 80% complete for clusters with mass in excess of 6 x 10(exp 14) solar masses referenced to the cluster volume characterized by 500 times the critical density. The Compton gamma-X-ray luminosity mass comparison for the 11 best-detected clusters visually agrees with both self-similar and non-adiabatic, simulation-derived scaling laws,

  5. A community-based cluster randomized survey of noncommunicable disease and risk factors in a peri-urban shantytown in Lima, Peru.

    Science.gov (United States)

    Heitzinger, Kristen; Montano, Silvia M; Hawes, Stephen E; Alarcón, Jorge O; Zunt, Joseph R

    2014-05-21

    An estimated 863 million people-a third of the world's urban population-live in slums, yet there is little information on the disease burden in these settings, particularly regarding chronic preventable diseases. From March to May 2012, we conducted a cluster randomized survey to estimate the prevalence of noncommunicable diseases (NCDs) and associated risk factors in a peri-urban shantytown north of Lima, Peru. Field workers administered a questionnaire that included items from the WHO World Health Survey and the WHO STEPS survey of chronic disease risk factors. We used logistic regression to assess the associations of NCDs and related risk factors with age and gender. We accounted for sampling weights and the clustered sampling design using statistical survey methods. A total of 142 adults were surveyed and had a weighted mean age of 36 years (range 18-81). The most prevalent diseases were depression (12%) and chronic respiratory disease (8%), while lifetime prevalence of cancer, arthritis, myocardial infarction, and diabetes were all less than 5%. Fifteen percent of respondents were hypertensive and the majority (67%) was unaware of their condition. Being overweight or obese was common for both genders (53%), but abdominal obesity was more prevalent in women (54% vs. 10% in men, p Peru and suggests that prevention and treatment interventions could be optimized according to age and gender.

  6. Weak-Lensing Mass Calibration of the Atacama Cosmology Telescope Equatorial Sunyaev-Zeldovich Cluster Sample with the Canada-France-Hawaii Telescope Stripe 82 Survey

    Science.gov (United States)

    Battaglia, N.; Leauthaud, A.; Miyatake, H.; Hasseleld, M.; Gralla, M. B.; Allison, R.; Bond, J. R.; Calabrese, E.; Crichton, D.; Devlin, M. J.; hide

    2016-01-01

    Mass calibration uncertainty is the largest systematic effect for using clustersof galaxies to constrain cosmological parameters. We present weak lensing mass measurements from the Canada-France-Hawaii Telescope Stripe 82 Survey for galaxy clusters selected through their high signal-to-noise thermal Sunyaev-Zeldovich (tSZ) signal measured with the Atacama Cosmology Telescope (ACT). For a sample of 9 ACT clusters with a tSZ signal-to-noise greater than five, the average weak lensing mass is (4.8 plus or minus 0.8) times 10 (sup 14) solar mass, consistent with the tSZ mass estimate of (4.7 plus or minus 1.0) times 10 (sup 14) solar mass, which assumes a universal pressure profile for the cluster gas. Our results are consistent with previous weak-lensing measurements of tSZ-detected clusters from the Planck satellite. When comparing our results, we estimate the Eddington bias correction for the sample intersection of Planck and weak-lensing clusters which was previously excluded.

  7. GALAXY CLUSTERS DISCOVERED VIA THE SUNYAEV-ZEL'DOVICH EFFECT IN THE 2500-SQUARE-DEGREE SPT-SZ SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Bleem, L. E.; Stalder, B.; de Haan, T.; Aird, K. A.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Bayliss, M.; Benson, B. A.; Bocquet, S.; Brodwin, M.; Carlstrom, J. E.; Chang, C. L.; Chiu, I.; Cho, H. M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; Desai, S.; Dietrich, J. P.; Dobbs, M. A.; Foley, R. J.; Forman, W. R.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Halverson, N. W.; Hennig, C.; Hoekstra, H.; Holder, G. P.; Holzapfel, W. L.; Hrubes, J. D.; Jones, C.; Keisler, R.; Knox, L.; Lee, A. T.; Leitch, E. M.; Liu, J.; Lueker, M.; Luong-Van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L.; Mohr, J. J.; Murray, S. S.; Padin, S.; Pryke, C.; Reichardt, C. L.; Rest, A.; Ruel, J.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Schrabback, T.; Shirokoff, E.; Song, J.; Spieler, H. G.; Stanford, S. A.; Staniszewski, Z.; Stark, A. A.; Story, K. T.; Stubbs, C. W.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zahn, O.; Zenteno, A.

    2015-01-29

    We present a catalog of galaxy clusters selected via their Sunyaev-Zel'dovich (SZ) effect signature from 2500 deg(2) of South Pole Telescope (SPT) data. This work represents the complete sample of clusters detected at high significance in the 2500 deg(2) SPT-SZ survey, which was completed in 2011. A total of 677 (409) cluster candidates are identified above a signal-to-noise threshold of ξ = 4.5 (5.0). Ground- and space-based optical and near-infrared (NIR) imaging confirms overdensities of similarly colored galaxies in the direction of 516 (or 76%) of the ξ > 4.5 candidates and 387 (or 95%) of the ξ > 5 candidates, the measured purity is consistent with expectations from simulations. Of these confirmed clusters, 415 were first identified in SPT data, including 251 new discoveries reported in this work. We estimate photometric redshifts for all candidates with identified optical and/or NIR counterparts, we additionally report redshifts derived from spectroscopic observations for 141 of these systems. The mass threshold of the catalog is roughly independent of redshift above z ~ 0.25 leading to a sample of massive clusters that extends to high redshift. The median mass of the sample is M (500c)(ρ(crit)) $\\sim 3.5\\times 10^{14}\\,M_\\odot \\,h_{70}^{-1}$, the median redshift is z (med) = 0.55, and the highest-redshift systems are at z > 1.4. The combination of large redshift extent, clean selection, and high typical mass makes this cluster sample of particular interest for cosmological analyses and studies of cluster formation and evolution.

  8. Action of the protoporphyrin-Ix (Pp-Ix) in the life period of Drosophila mutants deficient in endogenous antioxidants

    International Nuclear Information System (INIS)

    Vidal E, L. M.

    2012-01-01

    The human being is daily exposed to free radicals or reactive oxygen species (Ros), as a result of the breathing and the interactions with xenobiotics that can cause irreversible lesions in molecules and cellular structures and that they are associated to diseases like the cancer, neuro degenerative and to the acceleration of the normal process of aging. Fortunately, to reduce the damaging effect of the Ros the cell has endogenous antioxidant systems constituted by antioxidant enzymes as: the superoxide dismutase (Sod), the catalase (Cat), and the glutathione peroxidase and reductase. Even, when these systems are not enough, we find to the exogenous antioxidants that cooperate in the balance of the Ros, as the porphyrins that include to the chlorophyllin, the hemin and the bilirubin among others. The protoporphyrin-Ix (Pp-Ix) is a tetra pyrrole without metallic center with antimutagenic and antioxidant activity similar to that of the chlorophyllin. However, is also known that their over-expression has toxic effects, because induces Ros. In Drosophila melanogaster, recently was found that the Pp-Ix have dual action anti and persistent mutagenic. One of their possible mechanism to act like mutagen is through the Ros induction. To evaluate this possibility and based in that the increase in the Ros levels can accelerate the aging process, in the present work the Pp-Ix role was evaluated, in the life period of Drosophila melanogaster strains deficient in Sod and Cat, sensitive to radiation or oxidative stress (rad, whd and flr 3 ) and a wild one as control (C-S). Females and males of each strain were treated chronically for separate with sucrose or Pp-Ix and every 15 days a group of each sex was irradiated with 10 Gy of gamma rays. The results indicated that the chronic treatment with Pp-Ix and in combination with radiation, increased the life period of the C-S strain. The Sod strain had a contrary effect and this effect was pronounced with the combined treatment of Pp-Ix

  9. The rates and patterns of deletions in the human factor IX gene

    Energy Technology Data Exchange (ETDEWEB)

    Ketterling, R.P.; Vielhaber, E.L.; Lind, T.J.; Thorland, E.C.; Sommer S.S. (Mayo Clinic/Foundation, Rochester, MN (United States))

    1994-02-01

    Deletions are commonly observed in genes with either segments of highly homologous sequences or excessive gene length. However, in the factor IX gene and in most genes, deletions (of [ge]21 bp) are uncommon. The authors have analyzed DNA from 290 families with hemophilia B (203 independent mutations) and have found 12 deletions >20 bp. Eleven of these are >2 kb (range >3-163 kb), and one is 1.1 kb. The junctions of the four deletions that are completely contained within the factor IX gene have been determined. A novel mutation occurred in patient HB128: the data suggest that a 26.8-kb deletion occurred between two segments of alternating purines and pyrimidines and that a 2.3-kb sense strand segment derived from the deleted region was inserted. For a sample of 203 independent mutations, the authors estimate the [open quotes]baseline[close quotes] rates of deletional mutation per base pair per generation as a function of size. The rate for large (>2 kb)I deletions is exceedingly low. For every mutational event in which a given base is at the junction of a large deletion, there are an estimated 58 microdeletions (<20 bp) and 985 single-base substitutions at that base. Analysis of the nine reported deletion junctions in the factor IX gene literature reveals that (i) five are associated with inversion, orphan sequences, or sense strand insertions; (ii) four are simple deletions that display an excess of short direct repeats at their junctions; (iii) there is no dramatic clustering of junctions within the gene; and (iv) with the exception of alternating purines and pyrimidines, deletion junctions are not preferentially associated with repetitive DNA. 58 refs., 5 figs., 5 tabs.

  10. THE ACS FORNAX CLUSTER SURVEY. IV. DEPROJECTION OF THE SURFACE BRIGHTNESS PROFILES OF EARLY-TYPE GALAXIES IN THE VIRGO AND FORNAX CLUSTERS: INVESTIGATING THE 'CORE/POWER-LAW DICHOTOMY'

    International Nuclear Information System (INIS)

    Glass, Lisa; Ferrarese, Laura; Cote, Patrick; Blakeslee, John P.; Chen, Chin-Wei; Jordan, Andres; Infante, Leopoldo; Peng, Eric; Mei, Simona; Tonry, John L.; West, Michael J.

    2011-01-01

    Although early observations with the Hubble Space Telescope (HST) pointed to a sharp dichotomy among early-type galaxies in terms of the logarithmic slope γ' of their central surface brightness profiles, several studies in the past few years have called this finding into question. In particular, recent imaging surveys of 143 early-type galaxies belonging to the Virgo and Fornax Clusters using the Advanced Camera for Surveys (ACS) on board HST have not found a dichotomy in γ', but instead a systematic progression from central luminosity deficit to excess relative to the inward extrapolation of the best-fitting global Sersic model. Given that earlier studies also found that the dichotomy persisted when analyzing the deprojected density profile slopes, we investigate the distribution of the three-dimensional luminosity density profiles of the ACS Virgo and Fornax Cluster Survey galaxies. Having fitted the surface brightness profiles with modified Sersic models, we then deproject the galaxies using an Abel integral and measure the inner slopes γ 3D of the resulting luminosity density profiles at various fractions of the effective radius R e . We find no evidence of a dichotomy, but rather, a continuous variation in the central luminosity profiles as a function of galaxy magnitude. We introduce a parameter, Δ 3D , that measures the central deviation of the deprojected luminosity profiles from the global Sersic fit, showing that this parameter varies smoothly and systematically along the luminosity function.

  11. The PEP survey: clustering of infrared-selected galaxies and structure formation at z ˜ 2 in GOODS-South

    Science.gov (United States)

    Magliocchetti, M.; Santini, P.; Rodighiero, G.; Grazian, A.; Aussel, H.; Altieri, B.; Andreani, P.; Berta, S.; Cepa, J.; Castañeda, H.; Cimatti, A.; Daddi, E.; Elbaz, D.; Genzel, R.; Gruppioni, C.; Lutz, D.; Magnelli, B.; Maiolino, R.; Popesso, P.; Poglitsch, A.; Pozzi, F.; Sanchez-Portal, M.; Förster Schreiber, N. M.; Sturm, E.; Tacconi, L.; Valtchanov, I.

    2011-09-01

    This paper presents the first direct estimate of the 3D clustering properties of far-infrared sources up to z˜ 3. This has been possible thanks to the PACS Evolutionary Probe (PEP) survey of the GOODS-South field performed with the PACS instrument on board the Herschel satellite. 550 and 502 sources were detected respectively in the 100- and 160-μm channels down to fluxes ? mJy and ? mJy, cuts that ensure >80 per cent completeness of the two catalogues. More than 65 per cent of these sources have an (either photometric or spectroscopic) redshift determination from the MUSIC catalogue; this percentage rises to ˜95 per cent in the inner portion of GOODS-South which is covered by data at other wavelengths. An analysis of the deprojected two-point correlation function w(θ) over the whole redshift range spanned by the data reports for the (comoving) correlation length, r0˜ 6.3 and ˜6.7 Mpc, respectively at 100 and 160 μm, corresponding to dark matter halo masses M≳ 1012.4 M⊙, in an excellent agreement with previous estimates obtained for mid-IR selected sources in the same field. Objects at z˜ 2 instead seem to be more strongly clustered, with r0˜ 19 and ˜17 Mpc in the two considered PACS channels. This dramatic increase of the correlation length between z˜ 1 and ˜2 is connected with the presence, more visible at 100 μm than in the other band, of a wide (at least 4 Mpc across in projection), M≳ 1014 M⊙, filamentary structure which includes more than 50 per cent of the sources detected at z˜ 2. An investigation of the properties of such sources indicates the possibility of a boosted star-forming activity in those which reside within the overdense environment with respect to more isolated galaxies found in the same redshift range. If confirmed by larger data sets, this result can be explained as due to the combined effect of large reservoirs of gas available at high redshifts in deep potential wells such as those associated with large overdensities

  12. An updated survey of globular clusters in M 31. III. A spectroscopic metallicity scale for the Revised Bologna Catalog

    Science.gov (United States)

    Galleti, S.; Bellazzini, M.; Buzzoni, A.; Federici, L.; Fusi Pecci, F.

    2009-12-01

    Aims. We present a new homogeneous set of metallicity estimates based on Lick indices for the old globular clusters of the M 31 galaxy. The final aim is to add homogeneous spectroscopic metallicities to as many entries as possible of the Revised Bologna Catalog of M 31 clusters, by reporting Lick index measurements from any source (literature, new observations, etc.) on the same scale. Methods: New empirical relations of [Fe/H] as a function of [MgFe] and Mg2 indices are based on the well-studied galactic globular clusters, complemented with theoretical model predictions for -0.2≤ [Fe/H]≤ +0.5. Lick indices for M 31 clusters from various literature sources (225 clusters) and from new observations by our team (71 clusters) have been transformed into the Trager et al. system, yielding new metallicity estimates for 245 globular clusters of M 31. Results: Our values are in good agreement with recent estimates based on detailed spectral fitting and with those obtained from color magnitude diagrams of clusters imaged with the Hubble Space Telescope. The typical uncertainty on individual estimates is ≃±0.25 dex, as resulted from the comparison with metallicities derived from color magnitude diagrams of individual clusters. Conclusions: The metallicity distribution of M 31 globular cluster is briefly discussed and compared with that of the Milky Way. Simple parametric statistical tests suggest that the distribution is probably not unimodal. The strong correlation between metallicity and kinematics found in previous studies is confirmed. The most metal-rich GCs tend to be packed into the center of the system and to cluster tightly around the galactic rotation curve defined by the HI disk, while the velocity dispersion about the curve increases with decreasing metallicity. However, also the clusters with [Fe/H]<-1.0 display a clear rotation pattern, at odds with their Milky Way counterparts. Based on observations made at La Palma, at the Spanish Observatorio del Roque

  13. OPTICAL PROPERTIES OF THE ULTRALUMINOUS X-RAY SOURCE HOLMBERG IX X-1 AND ITS STELLAR ENVIRONMENT

    International Nuclear Information System (INIS)

    Grise, F.; Kaaret, P.; Pakull, M. W.; Motch, C.

    2011-01-01

    Holmberg IX X-1 is an archetypal ultraluminous X-ray source (ULX). Here we study the properties of the optical counterpart and of its stellar environment using optical data from SUBARU/Faint Object Camera and Spectrograph, GEMINI/GMOS-N and Hubble Space Telescope (HST)/Advanced Camera for Surveys, as well as simultaneous Chandra X-ray data. The V ∼ 22.6 spectroscopically identified optical counterpart is part of a loose cluster with an age ∼ sun . The counterpart is more luminous than the other stars of the association, suggesting a non-negligible optical contribution from the accretion disk. An observed UV excess also points to non-stellar light similar to X-ray active low-mass X-ray binaries. A broad He II λ4686 emission line identified in the optical spectrum of the ULX further suggests optical light from X-ray reprocessing in the accretion disk. Using stellar evolutionary tracks, we have constrained the mass of the counterpart to be ∼> 10 M sun , even if the accretion disk contributes significantly to the optical luminosity. Comparison of the photometric properties of the counterpart with binary models show that the donor may be more massive, ∼> 25 M sun , with the ULX system likely undergoing case AB mass transfer. Finally, the counterpart exhibits photometric variability of 0.14 mag between two HST observations separated by 50 days which could be due to ellipsoidal variations and/or disk reprocessing of variable X-ray emission.

  14. Data Summary Report for the Annual Fourmile Branch and F- and H-Area Seeplines, Appendix IX Metals and Radionuclides, 1998

    International Nuclear Information System (INIS)

    Koch, J.

    1999-01-01

    This report presents a summary of the definitive data validation and verification for the 1998 RFI/RI annual Appendix IX metals and radionuclides survey for Fourmile Branch and the F- and H-Area Seeplines. The validation process began with project mobilization and continued through the delivery of EDDs and this report

  15. XMM-NEWTON/SLOAN DIGITAL SKY SURVEY: STAR FORMATION EFFICIENCY IN GALAXY CLUSTERS AND CONSTRAINTS ON THE MATTER-DENSITY PARAMETER

    Energy Technology Data Exchange (ETDEWEB)

    Lagana, Tatiana F. [Universidade de Sao Paulo, Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Departamento de Astronomia, Cidade Universitaria, CEP:05508-090, Sao Paulo, SP (Brazil); Zhang Yuying; Reiprich, Thomas H.; Schneider, Peter [Argelander-Institut fuer Astronomie, Universitaet Bonn, 53121 Bonn (Germany)

    2011-12-10

    It is believed that the global baryon content of clusters of galaxies is representative of the matter distribution of the universe, and can, therefore, be used to reliably determine the matter-density parameter {Omega}{sub m}. This assumption is challenged by the growing evidence from optical and X-ray observations that the total baryon mass fraction increases toward rich clusters. In this context, we investigate the dependence of stellar and total baryon mass fractions as a function of mass. To do so, we used a subsample of 19 clusters extracted from the X-ray flux-limited sample HIFLUGCS that have available Sloan Digital Sky Survey Data Release 7 data. From the optical analysis we derived the stellar masses. Using XMM-Newton we derived the gas masses. Then, adopting a scaling relation we estimate the total masses. Adding the gas and the stellar mass fractions we obtain the total baryonic content that we find to increase with cluster mass, reaching seven-year Wilkinson Microwave Anisotropy Probe (WMAP7) prediction for clusters with M{sub 500} = 1.6 Multiplication-Sign 10{sup 15} M{sub Sun }. We observe a decrease of the stellar mass fraction (from 4.5% to {approx}1.0%) with increasing total mass where our findings for the stellar mass fraction agree with previous studies. This result suggests a difference in the number of stars formed per unit of halo mass, though with a large scatter for low-mass systems. That is, the efficiency of star formation varies on a cluster scale that lower mass systems are likely to have higher star formation efficiencies. It follows immediately that the dependence of the stellar mass fraction on total mass results in an increase of the mass-to-light ratio from lower to higher mass systems. We also discuss the consequences of these results in the context of determining the cosmic matter-density parameter {Omega}{sub m}.

  16. Cluster-sample surveys and lot quality assurance sampling to evaluate yellow fever immunisation coverage following a national campaign, Bolivia, 2007.

    Science.gov (United States)

    Pezzoli, Lorenzo; Pineda, Silvia; Halkyer, Percy; Crespo, Gladys; Andrews, Nick; Ronveaux, Olivier

    2009-03-01

    To estimate the yellow fever (YF) vaccine coverage for the endemic and non-endemic areas of Bolivia and to determine whether selected districts had acceptable levels of coverage (>70%). We conducted two surveys of 600 individuals (25 x 12 clusters) to estimate coverage in the endemic and non-endemic areas. We assessed 11 districts using lot quality assurance sampling (LQAS). The lot (district) sample was 35 individuals with six as decision value (alpha error 6% if true coverage 70%; beta error 6% if true coverage 90%). To increase feasibility, we divided the lots into five clusters of seven individuals; to investigate the effect of clustering, we calculated alpha and beta by conducting simulations where each cluster's true coverage was sampled from a normal distribution with a mean of 70% or 90% and standard deviations of 5% or 10%. Estimated coverage was 84.3% (95% CI: 78.9-89.7) in endemic areas, 86.8% (82.5-91.0) in non-endemic and 86.0% (82.8-89.1) nationally. LQAS showed that four lots had unacceptable coverage levels. In six lots, results were inconsistent with the estimated administrative coverage. The simulations suggested that the effect of clustering the lots is unlikely to have significantly increased the risk of making incorrect accept/reject decisions. Estimated YF coverage was high. Discrepancies between administrative coverage and LQAS results may be due to incorrect population data. Even allowing for clustering in LQAS, the statistical errors would remain low. Catch-up campaigns are recommended in districts with unacceptable coverage.

  17. Consumer clusters in Denmark based on coarse vegetable intake frequency, explained by hedonics, socio-demographic, health and food lifestyle factors. A cross-sectional national survey.

    Science.gov (United States)

    Beck, Tove K; Jensen, Sidsel; Simmelsgaard, Sonni Hansen; Kjeldsen, Chris; Kidmose, Ulla

    2015-08-01

    Vegetable intake seems to play a protective role against major lifestyle diseases. Despite this, the Danish population usually eats far less than the recommended daily intake. The present study focused on the intake of 17 coarse vegetables and the potential barriers limiting their intake. The present study drew upon a large Danish survey (n = 1079) to study the intake of coarse vegetables among Danish consumers. Four population clusters were identified based on their intake of 17 different coarse vegetables, and profiled according to hedonics, socio-demographic, health, and food lifestyle factors. The four clusters were characterized by a very low intake frequency of coarse vegetables ('low frequency'), a low intake frequency of coarse vegetables; but high intake frequency of carrots ('carrot eaters'), a moderate coarse vegetable intake frequency and high intake frequency of beetroot ('beetroot eaters'), and a high intake frequency of all coarse vegetables ('high frequency'). There was a relationship between reported liking and reported intake frequency for all tested vegetables. Preference for foods with a sweet, salty or bitter taste, in general, was also identified to be decisive for the reported vegetable intake, as these differed across the clusters. Each cluster had distinct socio-demographic, health and food lifestyle profiles. 'Low frequency' was characterized by uninvolved consumers with lack of interest in food, 'carrot eaters' vegetable intake was driven by health aspects, 'beetroot eaters' were characterized as traditional food consumers, and 'high frequency' were individuals with a strong food engagement and high vegetable liking. 'Low frequency' identified more barriers than other consumer clusters and specifically regarded low availability of pre-cut/prepared coarse vegetables on the market as a barrier. Across all clusters a low culinary knowledge was identified as the main barrier. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Militarization, human rights violations and community responses as determinants of health in southeastern Myanmar: results of a cluster survey.

    Science.gov (United States)

    Davis, William W; Mullany, Luke C; Schissler, Matt; Albert, Saw; Beyrer, Chris

    2015-01-01

    The Myanmar army and ethnic armed groups agreed to a preliminary ceasefire in 2012, but a heavy military presence remains in southeastern Myanmar. Qualitative data suggested this militarization can result in human rights abuses in the absence of armed engagements between the parties, and that rural ethnic civilians use a variety of self-protection strategies to avoid these abuses or reduce their negative impacts. We used data from a household survey to determine prevalence of select self-protection activities and to examine exposure to armed groups, human rights violations and self-protection activities as determinants of health in southeastern Myanmar. Data collected from 463 households via a two-stage cluster survey of conflict-affected areas in eastern Myanmar in January 2012, were analyzed using logistic regression models to identify associations between exposure to state and non-state armed groups, village self-protection, human rights abuses and health outcomes. Close proximity to a military base was associated with human rights abuses (PRR 1.30, 95 % CI: 1.14-1.48), inadequate food production (PRR 1.08, 95 % CI: 1.03-1.13), inability to access health care (PRR 1.29, 95 % CI: 1.04-1.60) and diarrhea (PRR 1.15, 95 % CI: 1.05-1.27. Direct exposure to armed groups was associated with household hunger (PRR1.71, 95 % CI: 1.30-2.23). Among households that reported no human rights abuses, risk of household hunger (PRR 5.64, 95 % CI: 1.88-16.91), inadequate food production (PRR 1.95, 95 % CI: 1.11-3.41) and diarrhea (PRR 2.53, 95 % CI: 1.45-4.42) increased when neighbors' households reported experiencing human rights abuses. Households in villages that reported negotiating with the Myanmar army had lower risk of human rights violations (PRR 0.91, 95 % CI: 0.85-0.98), household hunger (PRR 0.85, 95 % CI: 0.74-0.96), inadequate food production (PRR 0.93, 95 % CI:0.89-0.98) and diarrhea (PRR 0.89, 95 % CI:0.82-0.97). Stratified analysis suggests that self

  19. A Wide-Field Photometric Survey for Extratidal Tails Around Five Metal-Poor Globular Clusters in the Galactic Halo

    Science.gov (United States)

    Chun, Sang-Hyun; Kim, Jae-Woo; Sohn, Sangmo T.; Park, Jang-Hyun; Han, Wonyong; Kim, Ho-Il; Lee, Young-Wook; Lee, Myung Gyoon; Lee, Sang-Gak; Sohn, Young-Jong

    2010-02-01

    Wide-field deep g'r'i' images obtained with the Megacam of the Canada-France-Hawaii Telescope are used to investigate the spatial configuration of stars around five metal-poor globular clusters M15, M30, M53, NGC 5053, and NGC 5466, in a field-of-view ~3°. Applying a mask filtering algorithm to the color-magnitude diagrams of the observed stars, we sorted cluster's member star candidates that are used to examine the characteristics of the spatial stellar distribution surrounding the target clusters. The smoothed surface density maps and the overlaid isodensity contours indicate that all of the five metal-poor globular clusters exhibit strong evidence of extratidal overdensity features over their tidal radii, in the form of extended tidal tails around the clusters. The orientations of the observed extratidal features show signatures of tidal tails tracing the clusters' orbits, inferred from their proper motions, and effects of dynamical interactions with the Galaxy. Our findings include detections of a tidal bridge-like feature and an envelope structure around the pair of globular clusters M53 and NGC 5053. The observed radial surface density profiles of target clusters have a deviation from theoretical King models, for which the profiles show a break at 0.5-0.7rt , extending the overdensity features out to 1.5-2rt . Both radial surface density profiles for different angular sections and azimuthal number density profiles confirm the overdensity features of tidal tails around the five metal-poor globular clusters. Our results add further observational evidence that the observed metal-poor halo globular clusters originate from an accreted satellite system, indicative of the merging scenario of the formation of the Galactic halo. Based on observations carried out at the Canada-France-Hawaii Telescope, operated by the National Research Council of Canada, the Centre National de la Recherche Scientifique de France, and the University of Hawaii. This is part of the

  20. The Gaia-ESO Survey: the present-day radial metallicity distribution of the Galactic disc probed by pre-main-sequence clusters

    Science.gov (United States)

    Spina, L.; Randich, S.; Magrini, L.; Jeffries, R. D.; Friel, E. D.; Sacco, G. G.; Pancino, E.; Bonito, R.; Bravi, L.; Franciosini, E.; Klutsch, A.; Montes, D.; Gilmore, G.; Vallenari, A.; Bensby, T.; Bragaglia, A.; Flaccomio, E.; Koposov, S. E.; Korn, A. J.; Lanzafame, A. C.; Smiljanic, R.; Bayo, A.; Carraro, G.; Casey, A. R.; Costado, M. T.; Damiani, F.; Donati, P.; Frasca, A.; Hourihane, A.; Jofré, P.; Lewis, J.; Lind, K.; Monaco, L.; Morbidelli, L.; Prisinzano, L.; Sousa, S. G.; Worley, C. C.; Zaggia, S.

    2017-05-01

    Context. The radial metallicity distribution in the Galactic thin disc represents a crucial constraint for modelling disc formation and evolution. Open star clusters allow us to derive both the radial metallicity distribution and its evolution over time. Aims: In this paper we perform the first investigation of the present-day radial metallicity distribution based on [Fe/H] determinations in late type members of pre-main-sequence clusters. Because of their youth, these clusters are therefore essential for tracing the current interstellar medium metallicity. Methods: We used the products of the Gaia-ESO Survey analysis of 12 young regions (age ages is not easily explained by the models. Our results reveal a complex interplay of several processes (e.g. star formation activity, initial mass function, supernova yields, gas flows) that controlled the recent evolution of the Milky Way. Based on observations made with the ESO/VLT, at Paranal Observatory, under program 188.B-3002 (The Gaia-ESO Public Spectroscopic Survey).Full Table 1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/601/A70

  1. A VLT/MUSE galaxy survey towards QSO Q1410: looking for a WHIM traced by BLAs in inter-cluster filaments†

    Science.gov (United States)

    Pessa, Ismael; Tejos, Nicolas; Barrientos, L. Felipe; Werk, Jessica; Bielby, Richard; Padilla, Nelson; Morris, Simon L.; Prochaska, J. Xavier; Lopez, Sebastian; Hummels, Cameron

    2018-03-01

    Cosmological simulations predict that a significant fraction of the low-z baryon budget resides in large-scale filaments in the form of a diffuse plasma at temperatures T ˜ 105 - 107 K. However, direct observation of this so-called warm-hot intergalactic medium (WHIM) has been elusive. In the ΛCDM paradigm, galaxy clusters correspond to the nodes of the cosmic web at the intersection of several large-scale filamentary threads. In previous work, we used HST/COS data to conduct the first survey of broad H I Lyα absorbers (BLAs) potentially produced by WHIM in inter-cluster filaments. We targeted a single QSO, namely Q1410, whose sight-line intersects 7 independent inter-cluster axes at impact parameters cluster axes, we found 3 without any galaxy counterpart to stringent luminosity limits (˜4 × 108 L⊙ ˜0.01 L*), providing further evidence that these BLAs may represent genuine WHIM detections. We combined this sample with other suitable BLAs from the literature and inferred the corresponding baryon mean density for these filaments in the range Ω ^fil_bar= 0.02-0.04. Our rough estimates are consistent with the predictions from numerical simulations but still subject to large systematic uncertainties, mostly from the adopted geometry, ionization corrections and density profile.

  2. Clustering of near clusters versus cluster compactness

    International Nuclear Information System (INIS)

    Yu Gao; Yipeng Jing

    1989-01-01

    The clustering properties of near Zwicky clusters are studied by using the two-point angular correlation function. The angular correlation functions for compact and medium compact clusters, for open clusters, and for all near Zwicky clusters are estimated. The results show much stronger clustering for compact and medium compact clusters than for open clusters, and that open clusters have nearly the same clustering strength as galaxies. A detailed study of the compactness-dependence of correlation function strength is worth investigating. (author)

  3. Ares I-X: First Flight of a New Generation

    Science.gov (United States)

    Davis, Stephan R.; Askins, Bruce R.

    2010-01-01

    The Ares I-X suborbital development flight test demonstrated NASA s ability to design, develop, launch and control a new human-rated launch vehicle (Figure 14). This hands-on missions experience will provide the agency with necessary skills and insights regardless of the future direction of space exploration. The Ares I-X team, having executed a successful launch, will now focus on analyzing the flight data and extracting lessons learned that will be used to support the development of future vehicles.

  4. Synthesis of [119mSn]-mesoporphyrin IX dichloride

    International Nuclear Information System (INIS)

    Denissen, J.F.

    1990-01-01

    Tin mesoporphyrin IX dichloride (Sn-MPCl 2 ) is a heme oxygenase inhibitor of current clinical interest for the treatment of neonatal hyperbilirubinemia. The synthesis of [ 119m Sn]-MPCl 2 for drug metabolism and disposition studies is reported. [ 119m Sn]-MPCl 2 was prepared in 60% radiochemical yield by metalation of the porphyrin nucleus of mesoporphyrin IX dihydrochloride with tin(II)-119m acetate. The product had a specific activity of 43.4 mCi/mmol and a radiochemical purity of 99%, as determined by radio-HPLC analysis. (author)

  5. The evolution of the cluster optical galaxy luminosity function between z = 0.4 and 0.9 in the DAFT/FADA survey

    Science.gov (United States)

    Martinet, Nicolas; Durret, Florence; Guennou, Loïc; Adami, Christophe; Biviano, Andrea; Ulmer, Melville P.; Clowe, Douglas; Halliday, Claire; Ilbert, Olivier; Márquez, Isabel; Schirmer, Mischa

    2015-03-01

    Context. There is some disagreement about the abundance of faint galaxies in high-redshift clusters, with contradictory results in the literature arising from studies of the optical galaxy luminosity function (GLF) for small cluster samples. Aims: We compute GLFs for one of the largest medium-to-high-redshift (0.4 ≤ z DAFT/FADA survey in the B,V,R, and I rest-frame bands. We used photometric redshifts computed from BVRIZJ images to constrain galaxy cluster membership. We carried out a detailed estimate of the completeness of our data. We distinguished the red-sequence and blue galaxies using a V - I versus I colour-magnitude diagram. We studied the evolution of these two populations with redshift. We fitted Schechter functions to our stacked GLFs to determine average cluster characteristics. Results: We find that the shapes of our GLFs are similar for the B,V,R, and I bands with a drop at the red GLF faint ends that is more pronounced at high redshift: αred ~ -0.5 at 0.40 ≤ z 0.1 at 0.65 ≤ z < 0.90. The blue GLFs have a steeper faint end (αblue ~ -1.6) than the red GLFs, which appears to be independent of redshift. For the full cluster sample, blue and red GLFs meet at MV = -20, MR = -20.5, and MI = -20.3. A study of how galaxy types evolve with redshift shows that late-type galaxies appear to become early types between z ~ 0.9 and today. Finally, the faint ends of the red GLFs of more massive clusters appear to be richer than less massive clusters, which is more typical of the lower redshift behaviour. Conclusions: Our results indicate that these clusters form at redshifts higher than z = 0.9 from galaxy structures that already have an established red sequence. Late-type galaxies then appear to evolve into early types, enriching the red sequence between this redshift and today. This effect is consistent with the evolution of the faint-end slope of the red sequence and the galaxy type evolution that we find. Finally, faint galaxies accreted from the field

  6. Brightest Cluster Galaxies in REXCESS Clusters

    Science.gov (United States)

    Haarsma, Deborah B.; Leisman, L.; Bruch, S.; Donahue, M.

    2009-01-01

    Most galaxy clusters contain a Brightest Cluster Galaxy (BCG) which is larger than the other cluster ellipticals and has a more extended profile. In the hierarchical model, the BCG forms through many galaxy mergers in the crowded center of the cluster, and thus its properties give insight into the assembly of the cluster as a whole. In this project, we are working with the Representative XMM-Newton Cluster Structure Survey (REXCESS) team (Boehringer et al 2007) to study BCGs in 33 X-ray luminous galaxy clusters, 0.055 < z < 0.183. We are imaging the BCGs in R band at the Southern Observatory for Astrophysical Research (SOAR) in Chile. In this poster, we discuss our methods and give preliminary measurements of the BCG magnitudes, morphology, and stellar mass. We compare these BCG properties with the properties of their host clusters, particularly of the X-ray emitting gas.

  7. Effect of IX dosing on polypropylene and PVDF membrane fouling control

    KAUST Repository

    Myat, Darli Theint; Mergen, Max R D; Zhao, Oliver; Stewart, Matthew B.; Orbell, John D.; Merle, Tony; Croue, Jean-Philippe; Gray, Stephen R.

    2013-01-01

    The performance of ion exchange (IX) resin for organics removal from wastewater was assessed using advanced characterisation techniques for varying doses of IX. Organic characterisation using liquid chromatography with a photodiode array (PDA

  8. A random cluster survey and a convenience sample give comparable estimates of immunity to vaccine preventable diseases in children of school age in Victoria, Australia.

    Science.gov (United States)

    Kelly, Heath; Riddell, Michaela A; Gidding, Heather F; Nolan, Terry; Gilbert, Gwendolyn L

    2002-08-19

    We compared estimates of the age-specific population immunity to measles, mumps, rubella, hepatitis B and varicella zoster viruses in Victorian school children obtained by a national sero-survey, using a convenience sample of residual sera from diagnostic laboratories throughout Australia, with those from a three-stage random cluster survey. When grouped according to school age (primary or secondary school) there was no significant difference in the estimates of immunity to measles, mumps, hepatitis B or varicella. Compared with the convenience sample, the random cluster survey estimated higher immunity to rubella in samples from both primary (98.7% versus 93.6%, P = 0.002) and secondary school students (98.4% versus 93.2%, P = 0.03). Despite some limitations, this study suggests that the collection of a convenience sample of sera from diagnostic laboratories is an appropriate sampling strategy to provide population immunity data that will inform Australia's current and future immunisation policies. Copyright 2002 Elsevier Science Ltd.

  9. Hα3: an Hα imaging survey of HI selected galaxies from ALFALFA. II. Star formation properties of galaxies in the Virgo cluster and surroundings

    Science.gov (United States)

    Gavazzi, G.; Fumagalli, M.; Fossati, M.; Galardo, V.; Grossetti, F.; Boselli, A.; Giovanelli, R.; Haynes, M. P.

    2013-05-01

    Context. We present the analysis of Hα3, an Hα narrow-band imaging follow-up survey of 409 galaxies selected from the HI Arecibo Legacy Fast ALFA Survey (ALFALFA) in the Local Supercluster, including the Virgo cluster, in the region 11h advantage of Hα3, which provides the complete census of the recent massive star formation rate (SFR) in HI-rich galaxies in the local Universe and of ancillary optical data from SDSS we explore the relations between the stellar mass, the HI mass, and the current, massive SFR of nearby galaxies in the Virgo cluster. We compare these with those of isolated galaxies in the Local Supercluster, and we investigate the role of the environment in shaping the star formation properties of galaxies at the present cosmological epoch. Methods: By using the Hα hydrogen recombination line as a tracer of recent star formation, we investigated the relationships between atomic neutral gas and newly formed stars in different environments (cluster and field), for many morphological types (spirals and dwarfs), and over a wide range of stellar masses (107.5 to 1011.5 M⊙). To quantify the degree of environmental perturbation, we adopted an updated calibration of the HI deficiency parameter which we used to divide the sample into three classes: unperturbed galaxies (DefHI ≤ 0.3), perturbed galaxies (0.3 model. Once considered as a whole, the Virgo cluster is effective in removing neutral hydrogen from galaxies, and this perturbation is strong enough to appreciably reduce the SFR of its entire galaxy population. Conclusions: An estimate of the present infall rate of 300-400 galaxies per Gyr in the Virgo cluster is obtained from the number of existing HI-rich late-type systems, assuming 200-300 Myr as the time scale for HI ablation. If the infall process has been acting at a constant rate, this would imply that the Virgo cluster has formed approximately 2 Gyr ago, consistently with the idea that Virgo is in a young state of dynamical evolution. Based

  10. The Grism Lens-amplified Survey from Space (GLASS). IV. Mass Reconstruction of the Lensing Cluster Abell 2744 from Frontier Field Imaging and GLASS Spectroscopy

    Science.gov (United States)

    Wang, X.; Hoag, A.; Huang, K.-H.; Treu, T.; Bradač, M.; Schmidt, K. B.; Brammer, G. B.; Vulcani, B.; Jones, T. A.; Ryan, R. E., Jr.; Amorín, R.; Castellano, M.; Fontana, A.; Merlin, E.; Trenti, M.

    2015-09-01

    We present a strong and weak lensing reconstruction of the massive cluster Abell 2744, the first cluster for which deep Hubble Frontier Fields (HFF) images and spectroscopy from the Grism Lens-Amplified Survey from Space (GLASS) are available. By performing a targeted search for emission lines in multiply imaged sources using the GLASS spectra, we obtain five high-confidence spectroscopic redshifts and two tentative ones. We confirm one strongly lensed system by detecting the same emission lines in all three multiple images. We also search for additional line emitters blindly and use the full GLASS spectroscopic catalog to test reliability of photometric redshifts for faint line emitters. We see a reasonable agreement between our photometric and spectroscopic redshift measurements, when including nebular emission in photometric redshift estimations. We introduce a stringent procedure to identify only secure multiple image sets based on colors, morphology, and spectroscopy. By combining 7 multiple image systems with secure spectroscopic redshifts (at 5 distinct redshift planes) with 18 multiple image systems with secure photometric redshifts, we reconstruct the gravitational potential of the cluster pixellated on an adaptive grid, using a total of 72 images. The resulting mass map is compared with a stellar mass map obtained from the deep Spitzer Frontier Fields data to study the relative distribution of stars and dark matter in the cluster. We find that the stellar to total mass ratio varies substantially across the cluster field, suggesting that stars do not trace exactly the total mass in this interacting system. The maps of convergence, shear, and magnification are made available in the standard HFF format.

  11. THE GRISM LENS-AMPLIFIED SURVEY FROM SPACE (GLASS). V. EXTENT AND SPATIAL DISTRIBUTION OF STAR FORMATION IN z ∼ 0.5 CLUSTER GALAXIES

    International Nuclear Information System (INIS)

    Vulcani, Benedetta; Treu, Tommaso; Malkan, Matthew; Abramson, Louis; Schmidt, Kasper B.; Poggianti, Bianca M.; Dressler, Alan; Fontana, Adriano; Pentericci, Laura; Bradac, Marusa; Hoag, Austin; Huang, Kuan-Han; He, Julie; Brammer, Gabriel B.; Trenti, Michele; Linden, Anja von der; Morris, Glenn

    2015-01-01

    We present the first study of the spatial distribution of star formation in z ∼ 0.5 cluster galaxies. The analysis is based on data taken with the Wide Field Camera 3 as part of the Grism Lens-Amplified Survey from Space (GLASS). We illustrate the methodology by focusing on two clusters (MACS 0717.5+3745 and MACS 1423.8+2404) with different morphologies (one relaxed and one merging) and use foreground and background galaxies as a field control sample. The cluster+field sample consists of 42 galaxies with stellar masses in the range 10 8 –10 11 M ⊙  and star formation rates in the range 1–20 M ⊙ yr −1 . Both in clusters and in the field, Hα is more extended than the rest-frame UV continuum in 60% of the cases, consistent with diffuse star formation and inside-out growth. In ∼20% of the cases, the Hα emission appears more extended in cluster galaxies than in the field, pointing perhaps to ionized gas being stripped and/or star formation being enhanced at large radii. The peak of the Hα emission and that of the continuum are offset by less than 1 kpc. We investigate trends with the hot gas density as traced by the X-ray emission, and with the surface mass density as inferred from gravitational lens models, and find no conclusive results. The diversity of morphologies and sizes observed in Hα illustrates the complexity of the environmental processes that regulate star formation. Upcoming analysis of the full GLASS data set will increase our sample size by almost an order of magnitude, verifying and strengthening the inference from this initial data set

  12. THE NEXT GENERATION VIRGO CLUSTER SURVEY. X. PROPERTIES OF ULTRA-COMPACT DWARFS IN THE M87, M49, AND M60 REGIONS

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chengze [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Peng, Eric W.; Zhang, Hong-Xin [Department of Astronomy, Peking University, Beijing 100871 (China); Côté, Patrick; Ferrarese, Laura; Gwyn, Stephen; Blakeslee, John P. [Herzberg Institute of Astrophysics, National Research Council of Canada, Victoria, BC V9E 2E7 (Canada); Jordán, Andrés; Muñoz, Roberto P.; Puzia, Thomas H. [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 7820436 Macul, Santiago (Chile); Mihos, J. Christopher [Department of Astronomy, Case Western Reserve University, Cleveland, OH (United States); Lançon, Ariane [Observatoire Astronomique de Strasbourg, Université de Strasbourg and CNRS, UMR 7550, 11 rue de l’Université, F-67000 Strasbourg (France); Cuillandre, Jean-Charles [CEA/IRFU/SAp, Laboratoire AIM Paris-Saclay, CNRS/INSU, Université Paris Diderot, Observatoire de Paris, PSL Research University, F-91191 Gif-sur-Yvette Cedex (France); Boselli, Alessandro [Aix-Marseille Université, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, F-13388, Marseille (France); Durrell, Patrick R., E-mail: czliu@sjtu.edu.cn, E-mail: peng@pku.edu.cn [Department of Physics and Astronomy, Youngstown State University, One University Plaza, Youngstown, OH 44555 (United States); and others

    2015-10-10

    We use imaging from the Next Generation Virgo cluster Survey (NGVS) to present a comparative study of ultra-compact dwarf (UCD) galaxies associated with three prominent Virgo sub-clusters: those centered on the massive red-sequence galaxies M87, M49, and M60. We show how UCDs can be selected with high completeness using a combination of half-light radius and location in color–color diagrams (u*iK{sub s} or u*gz). Although the central galaxies in each of these sub-clusters have nearly identical luminosities and stellar masses, we find large differences in the sizes of their UCD populations, with M87 containing ∼3.5 and 7.8 times more UCDs than M49 and M60, respectively. The relative abundance of UCDs in the three regions scales in proportion to sub-cluster mass, as traced by X-ray gas mass, total gravitating mass, number of globular clusters (GCs), and number of nearby galaxies. We find that the UCDs are predominantly blue in color, with ∼85% of the UCDs having colors similar to blue GCs and stellar nuclei of dwarf galaxies. We present evidence that UCDs surrounding M87 and M49 may follow a morphological sequence ordered by the prominence of their outer, low surface brightness envelope, ultimately merging with the sequence of nucleated low-mass galaxies, and that envelope prominence correlates with distance from either galaxy. Our analysis provides evidence that tidal stripping of nucleated galaxies is an important process in the formation of UCDs.

  13. THE GRISM LENS-AMPLIFIED SURVEY FROM SPACE (GLASS). IV. MASS RECONSTRUCTION OF THE LENSING CLUSTER ABELL 2744 FROM FRONTIER FIELD IMAGING AND GLASS SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.; Schmidt, K. B.; Jones, T. A. [Department of Physics, University of California, Santa Barbara, CA 93106-9530 (United States); Hoag, A.; Huang, K.-H.; Bradac, M. [Department of Physics, University of California, Davis, CA 95616 (United States); Treu, T. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States); Brammer, G. B.; Ryan, R. E. Jr. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD, 21218 (United States); Vulcani, B. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo Institutes for Advanced Study (UTIAS), the University of Tokyo, Kashiwa, 277-8582 (Japan); Amorín, R.; Castellano, M.; Fontana, A.; Merlin, E. [INAF—Osservatorio Astronomico di Roma Via Frascati 33, I-00040 Monte Porzio Catone (Italy); Trenti, M., E-mail: xinwang@physics.ucsb.edu [School of Physics, The University of Melbourne, VIC 3010 (Australia)

    2015-09-20

    We present a strong and weak lensing reconstruction of the massive cluster Abell 2744, the first cluster for which deep Hubble Frontier Fields (HFF) images and spectroscopy from the Grism Lens-Amplified Survey from Space (GLASS) are available. By performing a targeted search for emission lines in multiply imaged sources using the GLASS spectra, we obtain five high-confidence spectroscopic redshifts and two tentative ones. We confirm one strongly lensed system by detecting the same emission lines in all three multiple images. We also search for additional line emitters blindly and use the full GLASS spectroscopic catalog to test reliability of photometric redshifts for faint line emitters. We see a reasonable agreement between our photometric and spectroscopic redshift measurements, when including nebular emission in photometric redshift estimations. We introduce a stringent procedure to identify only secure multiple image sets based on colors, morphology, and spectroscopy. By combining 7 multiple image systems with secure spectroscopic redshifts (at 5 distinct redshift planes) with 18 multiple image systems with secure photometric redshifts, we reconstruct the gravitational potential of the cluster pixellated on an adaptive grid, using a total of 72 images. The resulting mass map is compared with a stellar mass map obtained from the deep Spitzer Frontier Fields data to study the relative distribution of stars and dark matter in the cluster. We find that the stellar to total mass ratio varies substantially across the cluster field, suggesting that stars do not trace exactly the total mass in this interacting system. The maps of convergence, shear, and magnification are made available in the standard HFF format.

  14. THE GRISM LENS-AMPLIFIED SURVEY FROM SPACE (GLASS). V. EXTENT AND SPATIAL DISTRIBUTION OF STAR FORMATION IN z ∼ 0.5 CLUSTER GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Vulcani, Benedetta [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo Institutes for Advanced Study (UTIAS), the University of Tokyo, Kashiwa, 277-8582 (Japan); Treu, Tommaso; Malkan, Matthew; Abramson, Louis [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States); Schmidt, Kasper B. [Department of Physics, University of California, Santa Barbara, CA 93106-9530 (United States); Poggianti, Bianca M. [INAF-Astronomical Observatory of Padova (Italy); Dressler, Alan [The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Fontana, Adriano; Pentericci, Laura [INAF—Osservatorio Astronomico di Roma, Via Frascati 33, 00040 Monte Porzio Catone (Italy); Bradac, Marusa; Hoag, Austin; Huang, Kuan-Han; He, Julie [Department of Physics, University of California, Davis, CA 95616 (United States); Brammer, Gabriel B. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Trenti, Michele [School of Physics, University of Melbourne, VIC 3010 (Australia); Linden, Anja von der [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen Juliane Maries Vej 30, DK-2100 Copenhagen Ø (Denmark); Morris, Glenn [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, 452 Lomita Mall, Stanford, CA 94305-4085 (United States)

    2015-12-01

    We present the first study of the spatial distribution of star formation in z ∼ 0.5 cluster galaxies. The analysis is based on data taken with the Wide Field Camera 3 as part of the Grism Lens-Amplified Survey from Space (GLASS). We illustrate the methodology by focusing on two clusters (MACS 0717.5+3745 and MACS 1423.8+2404) with different morphologies (one relaxed and one merging) and use foreground and background galaxies as a field control sample. The cluster+field sample consists of 42 galaxies with stellar masses in the range 10{sup 8}–10{sup 11} M{sub ⊙} and star formation rates in the range 1–20 M{sub ⊙} yr{sup −1}. Both in clusters and in the field, Hα is more extended than the rest-frame UV continuum in 60% of the cases, consistent with diffuse star formation and inside-out growth. In ∼20% of the cases, the Hα emission appears more extended in cluster galaxies than in the field, pointing perhaps to ionized gas being stripped and/or star formation being enhanced at large radii. The peak of the Hα emission and that of the continuum are offset by less than 1 kpc. We investigate trends with the hot gas density as traced by the X-ray emission, and with the surface mass density as inferred from gravitational lens models, and find no conclusive results. The diversity of morphologies and sizes observed in Hα illustrates the complexity of the environmental processes that regulate star formation. Upcoming analysis of the full GLASS data set will increase our sample size by almost an order of magnitude, verifying and strengthening the inference from this initial data set.

  15. The Next Generation Virgo Cluster Survey (NGVS). XVIII. Measurement and Calibration of Surface Brightness Fluctuation Distances for Bright Galaxies in Virgo (and Beyond)

    Science.gov (United States)

    Cantiello, Michele; Blakeslee, John P.; Ferrarese, Laura; Côté, Patrick; Roediger, Joel C.; Raimondo, Gabriella; Peng, Eric W.; Gwyn, Stephen; Durrell, Patrick R.; Cuillandre, Jean-Charles

    2018-04-01

    We describe a program to measure surface brightness fluctuation (SBF) distances to galaxies observed in the Next Generation Virgo Cluster Survey (NGVS), a photometric imaging survey covering 104 deg2 of the Virgo cluster in the u*, g, i, and z bandpasses with the Canada–France–Hawaii Telescope. We describe the selection of the sample galaxies, the procedures for measuring the apparent i-band SBF magnitude {\\overline{m}}i, and the calibration of the absolute Mibar as a function of observed stellar population properties. The multiband NGVS data set provides multiple options for calibrating the SBF distances, and we explore various calibrations involving individual color indices as well as combinations of two different colors. Within the color range of the present sample, the two-color calibrations do not significantly improve the scatter with respect to wide-baseline, single-color calibrations involving u*. We adopt the ({u}* -z) calibration as a reference for the present galaxy sample, with an observed scatter of 0.11 mag. For a few cases that lack good u* photometry, we use an alternative relation based on a combination of (g-i) and (g-z) colors, with only a slightly larger observed scatter of 0.12 mag. The agreement of our measurements with the best existing distance estimates provides confidence that our measurements are accurate. We present a preliminary catalog of distances for 89 galaxies brighter than B T ≈ 13.0 mag within the survey footprint, including members of the background M and W Clouds at roughly twice the distance of the main body of the Virgo cluster. The extension of the present work to fainter and bluer galaxies is in progress.

  16. The VLT-FLAMES Tarantula Survey. III. A very massive star in apparent isolation from the massive cluster R136

    NARCIS (Netherlands)

    Bestenlehner, J.M.; Vink, J.S.; Gräfener, G.; Najarro, F.; Evans, C.J.; Bastian, N.; Bonanos, A.Z.; Bressert, E.; Crowther, P.A.; Doran, E.; Friedrich, K.; Hénault-Brunet, V.; Herrero, A.; de Koter, A.; Langer, N.; Lennon, D.J.; Maíz Apellániz, J.; Sana, H.; Soszynski, I.; Taylor, W.D.

    2011-01-01

    VFTS 682 is located in an active star-forming region, at a projected distance of 29 pc from the young massive cluster R136 in the Tarantula Nebula of the Large Magellanic Cloud. It was previously reported as a candidate young stellar object, and more recently spectroscopically revealed as a

  17. A Wide-Field, Broadband Imaging Survey of Butcher-Oemler Cluster Cl 0024+1654: The Catalog

    Science.gov (United States)

    Alexov, A.; Silva, D. R.; Pierce, M. J.

    2003-12-01

    Wide-field (20'×20') UBVI images of intermediate-redshift (z=0.39), Butcher-Oemler cluster Cl 0024+1654 have been obtained. These data probe the rest-frame mid-UV properties over a much larger area than previous studies of Cl 0024+1654. Using these data, a multicolor catalog of nonstellar objects, assumed to be galaxies, has been constructed and analyzed. Using statistical arguments, the observed galaxy sample is separated into field and cluster populations. The basic photometric properties of these populations are presented and discussed. The ``dropout'' objects (i.e., objects undetected in one or more photometric bands) in our catalog are also discussed. A description of the final UBVI images, as well as the object catalog, is provided in an appendix. In a second appendix the use of SExtractor in crowded fields, such as the core of Cl 0024+1654, is discussed. The specific issues of the mid-UV properties of red envelope cluster galaxies, as well as the possible detection of a faint blue cluster population, are discussed in a forthcoming companion paper by Silva, Alexov, & Pierce. The observations described were conducted at Kitt Peak National Observatory, National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) Inc., under cooperative agreement with the National Science Foundation (NSF).

  18. IX : An OS for datacenter applications with aggressive networking requirements

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    The conventional wisdom is that aggressive networking requirements, such as high packet rates for small messages and microsecond-scale tail latency, are best addressed outside the kernel, in a user-level networking stack. We present IX, a dataplane operating system designed to support low-latency, high-throughput and high-connection count applications.  Like classic operating systems such as Linux, IX provides strong protection guarantees to the networking stack.  However, and unlike classic operating systems, IX is designed for the ground up to support applications with aggressive networking requirements on dense multi-core platforms with 10GbE and 40GbE Ethernet NICs.  IX outperforms Linux by an order of magnitude on micro benchmarks, and by up to 3.6x when running an unmodified memcached, a popular key-value store. The presentation is based on the joint work with Adam Belay, George Prekas, Ana Klimovic, Sam Grossman and Christos Kozyrakis, published at OSDI 2014; Best P...

  19. Dynamic of exact perturbations in Bianchi IX type cosmological models

    International Nuclear Information System (INIS)

    Mello Neto, J.R.T. de.

    1985-01-01

    The dynamic of Bianchi IX type cosmological models is studied, after reducing Einstein equations to Hamiltonian system. Using the Melnikov method, the existence of chaos in the dynamic of these models is proved, and some numerical experiments are carried out. (M.C.K.) [pt

  20. Phase-space dynamics of Bianchi IX cosmological models

    International Nuclear Information System (INIS)

    Soares, I.D.

    1985-01-01

    The complex phase-space dynamical behaviour of a class of Biachi IX cosmological models is discussed, as the chaotic gravitational collapse due Poincare's homoclinic phenomena, and the n-furcation of periodic orbits and tori in the phase space of the models. Poincare maps which show this behaviour are constructed merically and applications are discussed. (Author) [pt

  1. Methods of producing protoporphyrin IX and bacterial mutants therefor

    Science.gov (United States)

    Zhou, Jizhong; Qiu, Dongru; He, Zhili; Xie, Ming

    2016-03-01

    The presently disclosed inventive concepts are directed in certain embodiments to a method of producing protoporphyrin IX by (1) cultivating a strain of Shewanella bacteria in a culture medium under conditions suitable for growth thereof, and (2) recovering the protoporphyrin IX from the culture medium. The strain of Shewanella bacteria comprises at least one mutant hemH gene which is incapable of normal expression, thereby causing an accumulation of protoporphyrin IX. In certain embodiments of the method, the strain of Shewanella bacteria is a strain of S. loihica, and more specifically may be S. loihica PV-4. In certain embodiments, the mutant hemH gene of the strain of Shewanella bacteria may be a mutant of shew_2229 and/or of shew_1140. In other embodiments, the presently disclosed inventive concepts are directed to mutant strains of Shewanella bacteria having at least one mutant hemH gene which is incapable of normal expression, thereby causing an accumulation of protoporphyrin IX during cultivation of the bacteria. In certain embodiments the strain of Shewanella bacteria is a strain of S. loihica, and more specifically may be S. loihica PV-4. In certain embodiments, the mutant hemH gene of the strain of Shewanella bacteria may be a mutant of shew_2229 and/or shew_1140.

  2. 23. IX korraldab Vaala galerii kunstioksjoni "Väliseesti eri"

    Index Scriptorium Estoniae

    2004-01-01

    Oksjonil on esindatud Eerik Haamer, Jaan Grünberg, Arno Vihalemm, Eduard Wiiralt, Ruth Tulving, Endel Kõks, Harald Jürissaar, Otto Paas, Ville Tops, Otto Puusta. Töödega saab tutvuda alates 18. IX, traditsiooniline sügisoksjon toimub 18. XI

  3. IX Congress of Spanish radiation protection Society (Bilbao, May-2002)

    International Nuclear Information System (INIS)

    2002-01-01

    The present book contains the papers presented to the IX Congress of Spanish Radiation Protection Society. The main sessions were : 1.- Scientific area of Radiation Protection and Regulation, Social aspects, Radioactive waste management and Dismantling. 2.- Radiation protection in Medical applications. 3.- Physics of radiations and their measurements

  4. Study of primitive universe in the Bianchi IX model

    International Nuclear Information System (INIS)

    Matsas, G.E.A.

    1988-03-01

    The theory of general relativity is used to study the homogeneous cosmological model Bianch IX with isometry group SO(3) near the cosmological singularity. The Bogoyavlenskii-Novikov formalism to explain the anusual behaviour of the Liapunov exponent associated with this chaotic system, is introduced. (author) [pt

  5. Title IX and Sexual Harassment of Student Athletes.

    Science.gov (United States)

    Wolohan, John T.

    1995-01-01

    This article reviews what constitutes sexual harassment in sports by examining Title IX of the Education Amendments of 1972 and the effect it has had on charges of sexual harrassment in educational institutions. Athletic administrators are provided with strategies and recommendations to help schools and athletic departments develop sexual…

  6. Management of cluster headache

    DEFF Research Database (Denmark)

    Tfelt-Hansen, Peer C; Jensen, Rigmor H

    2012-01-01

    The prevalence of cluster headache is 0.1% and cluster headache is often not diagnosed or misdiagnosed as migraine or sinusitis. In cluster headache there is often a considerable diagnostic delay - an average of 7 years in a population-based survey. Cluster headache is characterized by very severe...... or severe orbital or periorbital pain with a duration of 15-180 minutes. The cluster headache attacks are accompanied by characteristic associated unilateral symptoms such as tearing, nasal congestion and/or rhinorrhoea, eyelid oedema, miosis and/or ptosis. In addition, there is a sense of restlessness...... and agitation. Patients may have up to eight attacks per day. Episodic cluster headache (ECH) occurs in clusters of weeks to months duration, whereas chronic cluster headache (CCH) attacks occur for more than 1 year without remissions. Management of cluster headache is divided into acute attack treatment...

  7. Soluble form of carbonic anhydrase IX (CA IX) in the serum and urine of renal carcinoma patients

    Czech Academy of Sciences Publication Activity Database

    Závada, Jan; Závadová, Zuzana; Zaťovičová, M.; Hyršl, L.; Kawaciuk, I.

    2003-01-01

    Roč. 89, - (2003), s. 1067-1071 ISSN 0007-0920 R&D Projects: GA ČR GA301/99/0356 Institutional research plan: CEZ:AV0Z5052915 Keywords : carbonic anhydrase IX * tumor antigens * cancer diagnostics Subject RIV: EC - Immunology Impact factor: 3.894, year: 2003

  8. The Pan-STARRS1 Medium-deep Survey: Star Formation Quenching in Group and Cluster Environments

    Energy Technology Data Exchange (ETDEWEB)

    Jian, Hung-Yu; Lin, Lihwai; Lin, Kai-Yang; Chen, Chin-Wei [Institute of Astronomy and Astrophysics, Academia Sinica, 106, Taipei, Taiwan, R.O.C. (China); Foucaud, Sebastien [Department of Earth Sciences, National Taiwan Normal University, N.88, Tingzhou Road, Sec. 4, Taipei 11677, Taiwan, R.O.C. (China); Chiueh, Tzihong [Department of Physics, National Taiwan University, 106, Taipei, Taiwan, R.O.C. (China); Bower, R. G.; Cole, Shaun; Draper, P. W.; Metcalfe, N. [Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Chen, Wen-Ping [Graduate Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan, R.O.C. (China); Burgett, W. S.; Flewelling, H.; Huber, M. E.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Wainscoat, R. J.; Waters, C., E-mail: hyjian@asiaa.sinica.edu.tw [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

    2017-08-10

    We make use of a catalog of 1600 Pan-STARRS1 groups produced by the probability friends-of-friends algorithm to explore how the galaxy properties, i.e., the specific star formation rate (SSFR) and quiescent fraction, depend on stellar mass and group-centric radius. The work is the extension of Lin et al. In this work, powered by a stacking technique plus a background subtraction for contamination removal, a finer correction and more precise results are obtained than in our previous work. We find that while the quiescent fraction increases with decreasing group-centric radius, the median SSFRs of star-forming galaxies in groups at fixed stellar mass drop slightly from the field toward the group center. This suggests that the main quenching process in groups is likely a fast mechanism. On the other hand, a reduction in SSFRs by ∼0.2 dex is seen inside clusters as opposed to the field galaxies. If the reduction is attributed to the slow quenching effect, the slow quenching process acts dominantly in clusters. In addition, we also examine the density–color relation, where the density is defined by using a sixth-nearest-neighbor approach. Comparing the quiescent fractions contributed from the density and radial effect, we find that the density effect dominates the massive group or cluster galaxies, and the radial effect becomes more effective in less massive galaxies. The results support mergers and/or starvation as the main quenching mechanisms in the group environment, while harassment and/or starvation dominate in clusters.

  9. Identifying models of HIV care and treatment service delivery in Tanzania, Uganda, and Zambia using cluster analysis and Delphi survey.

    Science.gov (United States)

    Tsui, Sharon; Denison, Julie A; Kennedy, Caitlin E; Chang, Larry W; Koole, Olivier; Torpey, Kwasi; Van Praag, Eric; Farley, Jason; Ford, Nathan; Stuart, Leine; Wabwire-Mangen, Fred

    2017-12-06

    Organization of HIV care and treatment services, including clinic staffing and services, may shape clinical and financial outcomes, yet there has been little attempt to describe different models of HIV care in sub-Saharan Africa (SSA). Information about the relative benefits and drawbacks of different models could inform the scale-up of antiretroviral therapy (ART) and associated services in resource-limited settings (RLS), especially in light of expanded client populations with country adoption of WHO's test and treat recommendation. We characterized task-shifting/task-sharing practices in 19 diverse ART clinics in Tanzania, Uganda, and Zambia and used cluster analysis to identify unique models of service provision. We ran descriptive statistics to explore how the clusters varied by environmental factors and programmatic characteristics. Finally, we employed the Delphi Method to make systematic use of expert opinions to ensure that the cluster variables were meaningful in the context of actual task-shifting of ART services in SSA. The cluster analysis identified three task-shifting/task-sharing models. The main differences across models were the availability of medical doctors, the scope of clinical responsibility assigned to nurses, and the use of lay health care workers. Patterns of healthcare staffing in HIV service delivery were associated with different environmental factors (e.g., health facility levels, urban vs. rural settings) and programme characteristics (e.g., community ART distribution or integrated tuberculosis treatment on-site). Understanding the relative advantages and disadvantages of different models of care can help national programmes adapt to increased client load, select optimal adherence strategies within decentralized models of care, and identify differentiated models of care for clients to meet the growing needs of long-term ART patients who require more complicated treatment management.

  10. Comparative proteomic analysis of normal and collagen IX null mouse cartilage reveals altered extracellular matrix composition and novel components of the collagen IX interactome.

    Science.gov (United States)

    Brachvogel, Bent; Zaucke, Frank; Dave, Keyur; Norris, Emma L; Stermann, Jacek; Dayakli, Münire; Koch, Manuel; Gorman, Jeffrey J; Bateman, John F; Wilson, Richard

    2013-05-10

    Collagen IX is an integral cartilage extracellular matrix component important in skeletal development and joint function. Proteomic analysis and validation studies revealed novel alterations in collagen IX null cartilage. Matrilin-4, collagen XII, thrombospondin-4, fibronectin, βig-h3, and epiphycan are components of the in vivo collagen IX interactome. We applied a proteomics approach to advance our understanding of collagen IX ablation in cartilage. The cartilage extracellular matrix is essential for endochondral bone development and joint function. In addition to the major aggrecan/collagen II framework, the interacting complex of collagen IX, matrilin-3, and cartilage oligomeric matrix protein (COMP) is essential for cartilage matrix stability, as mutations in Col9a1, Col9a2, Col9a3, Comp, and Matn3 genes cause multiple epiphyseal dysplasia, in which patients develop early onset osteoarthritis. In mice, collagen IX ablation results in severely disturbed growth plate organization, hypocellular regions, and abnormal chondrocyte shape. This abnormal differentiation is likely to involve altered cell-matrix interactions but the mechanism is not known. To investigate the molecular basis of the collagen IX null phenotype we analyzed global differences in protein abundance between wild-type and knock-out femoral head cartilage by capillary HPLC tandem mass spectrometry. We identified 297 proteins in 3-day cartilage and 397 proteins in 21-day cartilage. Components that were differentially abundant between wild-type and collagen IX-deficient cartilage included 15 extracellular matrix proteins. Collagen IX ablation was associated with dramatically reduced COMP and matrilin-3, consistent with known interactions. Matrilin-1, matrilin-4, epiphycan, and thrombospondin-4 levels were reduced in collagen IX null cartilage, providing the first in vivo evidence for these proteins belonging to the collagen IX interactome. Thrombospondin-4 expression was reduced at the mRNA level

  11. EVIDENCE OF AGB POLLUTION IN GALACTIC GLOBULAR CLUSTERS FROM THE Mg–Al ANTICORRELATIONS OBSERVED BY THE APOGEE SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Ventura, P.; Dell’Agli, F.; D’Antona, F.; Di Criscienzo, M.; Tailo, M. [INAF–Osservatorio Astronomico di Roma, via Frascati 33, I-00077 Monteporzio (Italy); García-Hernández, D. A.; Zamora, O. [Instituto de Astrofísica de Canarias (IAC), E-38205 La Laguna, Tenerife (Spain); Mészáros, Sz. [ELTE Gothard Astrophysical Observatory, H-9704 Szombat-hely, Szent Imre Herceg st. 112 (Hungary); Lucatello, S. [INAF–Osservatorio Astronomico di Padova, vicolo dell’Osservatorio 5, I-35122 Padova (Italy); Shetrone, M. [University of Texas at Austin, McDonald Observatory, Austin, TX (United States); Tang, Baitian [Departamento de Astronomía, Casilla, 160-C, Universidad de Concepción, Concepción (Chile)

    2016-11-10

    We study the formation of multiple populations in globular clusters (GCs), under the hypothesis that stars in the second generation formed from the winds of intermediate-mass stars, ejected during the asymptotic giant branch (AGB) phase, possibly diluted with pristine gas, sharing the same chemical composition of first-generation stars. To this aim, we use the recent Apache Point Observatory Galactic Evolution Experiment (APOGEE) data, which provide the surface chemistry of a large sample of giant stars, belonging to clusters that span a wide metallicity range. The APOGEE data set is particularly suitable to discriminate among the various pollution scenarios proposed so far, as it provides the surface abundances of Mg and Al, the two elements involved in a nuclear channel extremely sensitive to the temperature, hence to the metallicity of the polluters. The present analysis shows a remarkable agreement between the observations and the theoretical yields from massive AGB stars. In particular, the observed extension of the depletion of Mg and O and the increase in Al is well reproduced by the models and the trend with the metallicity is also fully accounted for. This study further supports the idea that AGB stars were the key players in the pollution of the intra-cluster medium, from which additional generations of stars formed in GCs.

  12. A two-stage cluster sampling method using gridded population data, a GIS, and Google EarthTM imagery in a population-based mortality survey in Iraq

    Directory of Open Access Journals (Sweden)

    Galway LP

    2012-04-01

    Full Text Available Abstract Background Mortality estimates can measure and monitor the impacts of conflict on a population, guide humanitarian efforts, and help to better understand the public health impacts of conflict. Vital statistics registration and surveillance systems are rarely functional in conflict settings, posing a challenge of estimating mortality using retrospective population-based surveys. Results We present a two-stage cluster sampling method for application in population-based mortality surveys. The sampling method utilizes gridded population data and a geographic information system (GIS to select clusters in the first sampling stage and Google Earth TM imagery and sampling grids to select households in the second sampling stage. The sampling method is implemented in a household mortality study in Iraq in 2011. Factors affecting feasibility and methodological quality are described. Conclusion Sampling is a challenge in retrospective population-based mortality studies and alternatives that improve on the conventional approaches are needed. The sampling strategy presented here was designed to generate a representative sample of the Iraqi population while reducing the potential for bias and considering the context specific challenges of the study setting. This sampling strategy, or variations on it, are adaptable and should be considered and tested in other conflict settings.

  13. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: theoretical systematics and Baryon Acoustic Oscillations in the galaxy correlation function

    Science.gov (United States)

    Vargas-Magaña, Mariana; Ho, Shirley; Cuesta, Antonio J.; O'Connell, Ross; Ross, Ashley J.; Eisenstein, Daniel J.; Percival, Will J.; Grieb, Jan Niklas; Sánchez, Ariel G.; Tinker, Jeremy L.; Tojeiro, Rita; Beutler, Florian; Chuang, Chia-Hsun; Kitaura, Francisco-Shu; Prada, Francisco; Rodríguez-Torres, Sergio A.; Rossi, Graziano; Seo, Hee-Jong; Brownstein, Joel R.; Olmstead, Matthew; Thomas, Daniel

    2018-06-01

    We investigate the potential sources of theoretical systematics in the anisotropic Baryon Acoustic Oscillation (BAO) distance scale measurements from the clustering of galaxies in configuration space using the final Data Release (DR12) of the Baryon Oscillation Spectroscopic Survey (BOSS). We perform a detailed study of the impact on BAO measurements from choices in the methodology such as fiducial cosmology, clustering estimators, random catalogues, fitting templates, and covariance matrices. The theoretical systematic uncertainties in BAO parameters are found to be 0.002 in the isotropic dilation α and 0.003 in the quadrupolar dilation ɛ. The leading source of systematic uncertainty is related to the reconstruction techniques. Theoretical uncertainties are sub-dominant compared with the statistical uncertainties for BOSS survey, accounting 0.2σstat for α and 0.25σstat for ɛ (σα, stat ˜ 0.010 and σɛ, stat ˜ 0.012, respectively). We also present BAO-only distance scale constraints from the anisotropic analysis of the correlation function. Our constraints on the angular diameter distance DA(z) and the Hubble parameter H(z), including both statistical and theoretical systematic uncertainties, are 1.5 per cent and 2.8 per cent at zeff = 0.38, 1.4 per cent and 2.4 per cent at zeff = 0.51, and 1.7 per cent and 2.6 per cent at zeff = 0.61. This paper is part of a set that analyses the final galaxy clustering data set from BOSS. The measurements and likelihoods presented here are cross-checked with other BAO analysis in Alam et al. The systematic error budget concerning the methodology on post-reconstruction BAO analysis presented here is used in Alam et al. to produce the final cosmological constraints from BOSS.

  14. NEAR-INFRARED IMAGING AND SPECTROSCOPIC SURVEY OF THE SOUTHERN REGION OF THE YOUNG OPEN CLUSTER NGC 2264

    Energy Technology Data Exchange (ETDEWEB)

    Marinas, Naibi; Lada, Elizabeth A. [Astronomy Department, University of Florida, Gainesville, FL 32611 (United States); Teixiera, Paula S. [Department of Astrophysics, University of Vienna, Tuerkenschanzstrasse 17, A-1180 Vienna (Austria); Lada, Charles J. [Harvard-Smithsonian CFA, Cambridge, MA (United States)

    2013-08-01

    We have obtained JHK near-IR images and JH band low-resolution spectra of candidate members of the southern region of the young open cluster NGC 2264. We have determined spectral types from H-band spectra for 54 sources, 25 of which are classified for the first time. The stars in our sample cover a large range of spectral types (A8-M8). Using a cluster distance of 780 pc, we determined a median age of 1 Myr for this region of NGC 2264, with 90% of the stars being 5 Myr or younger. To improve the statistical significance of our sample, we included 66 additional cluster members within our field of view with optical spectral classification in the literature. We derived infrared excesses using stellar properties to model the photospheric emission for each source and the extinction to correct FLAMINGOS near-IR and Spitzer mid-IR photometry, and obtained a disk fraction of 51% {+-} 5% for the region. Binning the stars by stellar mass, we find a disk fraction of 38% {+-} 9% for the 0.1-0.3 solar mass group, 55% {+-} 6% for 0.3-1 solar masses, and 58% {+-} 10% for the higher than 1 solar mass group. The lower disk fraction for the lower mass stars is similar to the results found in non-cluster regions like Taurus and Chamaeleon, but differs from the older 3 Myr cluster IC 348 in which the disk fraction is lower for the higher mass stars. This mass-dependent disk fraction is accentuated in the sample with isochrone ages younger than 2 Myr. Here, we find that 45% {+-} 11% of the 0.1-0.3 solar mass stars have disks, 60% {+-} 7% of the 0.3-1 solar mass stars have disks, and all 1-3 solar mass stars have disks. Stellar masses might be an important factor in the ability of a system to form or retain a disk early on. However, regardless of the stellar mass, the large infrared excesses expected from optically thick disks disappear within the first 2 Myr for all stars in our study and small excesses from optically thin disks are found mostly in sources younger than 4 Myr.

  15. The Next Generation Virgo Cluster Survey. VII. The Intrinsic Shapes of Low-luminosity Galaxies in the Core of the Virgo Cluster, and a Comparison with the Local Group

    Science.gov (United States)

    Sánchez-Janssen, Rubén; Ferrarese, Laura; MacArthur, Lauren A.; Côté, Patrick; Blakeslee, John P.; Cuillandre, Jean-Charles; Duc, Pierre-Alain; Durrell, Patrick; Gwyn, Stephen; McConnacchie, Alan W.; Boselli, Alessandro; Courteau, Stéphane; Emsellem, Eric; Mei, Simona; Peng, Eric; Puzia, Thomas H.; Roediger, Joel; Simard, Luc; Boyer, Fred; Santos, Matthew

    2016-03-01

    We investigate the intrinsic shapes of low-luminosity galaxies in the central 300 kpc of the Virgo Cluster using deep imaging obtained as part of the Next Generation Virgo Cluster Survey (NGVS). We build a sample of nearly 300 red-sequence cluster members in the yet-unexplored -14 families of triaxial models with normally distributed intrinsic ellipticities, E = 1 - C/A, and triaxialities, T = (A2 - B2)/(A2 - C2). We develop a Bayesian framework to explore the posterior distribution of the model parameters, which allows us to work directly on discrete data, and to account for individual, surface-brightness-dependent axis ratio uncertainties. For this population we infer a mean intrinsic ellipticity \\bar{E} = {0.43}-0.02+0.02 and a mean triaxiality \\bar{T} = {0.16}-0.06+0.07. This implies that faint Virgo galaxies are best described as a family of thick, nearly oblate spheroids with mean intrinsic axis ratios 1:0.94:0.57. The core of Virgo lacks highly elongated low-luminosity galaxies, with 95% of the population having q > 0.45. We additionally attempt a study of the intrinsic shapes of Local Group (LG) satellites of similar luminosities. For the LG population we infer a slightly larger mean intrinsic ellipticity \\bar{E} = {0.51}-0.06+0.07, and the paucity of objects with round apparent shapes translates into more triaxial mean shapes, 1:0.76:0.49. Numerical studies that follow the tidal evolution of satellites within LG-sized halos are in good agreement with the inferred shape distributions, but the mismatch for faint galaxies in Virgo highlights the need for more adequate simulations of this population in the cluster environment. We finally compare the intrinsic shapes of NGVS low-mass galaxies with samples of more massive quiescent systems, and with field, star-forming galaxies of similar luminosities. We find that the intrinsic flattening in this low-luminosity regime is almost independent of the environment in which the galaxy resides, but there is a hint

  16. Is the cluster risk model of parental adversities better than the cumulative risk model as an indicator of childhood physical abuse?: findings from two representative community surveys.

    Science.gov (United States)

    Fuller-Thomson, E; Sawyer, J-L

    2014-01-01

    Screening strategies for childhood physical abuse (CPA) need to be improved in order to identify those most at risk. This study uses two regionally representative community samples to examine whether a cluster or cumulative model of risk indicators (i.e. parental divorce, parental unemployment, and parental addictions) explains a larger proportion of the variation in CPA. Data were drawn from Statistics Canada's National Population Health Survey (1994-1995) and Canadian Community Health Survey 3.1 (2005). Response rates were greater than 80% in both samples. Each survey had approximately 13,000 respondents aged 18 and over who answered questions about the above adverse childhood experiences. A gradient was shown with similar outcomes in each data set. Only 3.4% of adults who experienced none of the three risk indicators reported they had been physically abused during childhood or adolescence. The prevalence of CPA was greater among those who experienced parental divorce alone (8.3%-10.7%), parental unemployment alone (8.9%-9.7%) or parental addictions alone (18.0%-19.5%). When all three risk indicators were present, the prevalence of CPA ranged from 36.0%-41.0% and the age-sex-race adjusted odds were greater than 15 times that of individuals with none of the three risk indicators. The cluster model explained a statistically significantly larger proportion of the variation than the cumulative model although the difference between the two models was modest. For the purposes of parsimony, the cumulative model may be the better alternative. Adults who were exposed to two or more childhood risk indicators were much more likely to report that they were physically abused during their childhood than those with only one or no risk factors. Medical professionals may use this information on cumulative risk factors to more effectively target screening for potential CPA. Future research should include prospective studies. © 2012 John Wiley & Sons Ltd.

  17. Arabidopsis Lectin Receptor Kinases LecRK-IX.1 and LecRK-IX.2 Are Functional Analogs in Regulating Phytophthora Resistance and Plant Cell Death.

    Science.gov (United States)

    Wang, Yan; Cordewener, Jan H G; America, Antoine H P; Shan, Weixing; Bouwmeester, Klaas; Govers, Francine

    2015-09-01

    L-type lectin receptor kinases (LecRK) are potential immune receptors. Here, we characterized two closely-related Arabidopsis LecRK, LecRK-IX.1 and LecRK-IX.2, of which T-DNA insertion mutants showed compromised resistance to Phytophthora brassicae and Phytophthora capsici, with double mutants showing additive susceptibility. Overexpression of LecRK-IX.1 or LecRK-IX.2 in Arabidopsis and transient expression in Nicotiana benthamiana increased Phytophthora resistance but also induced cell death. Phytophthora resistance required both the lectin domain and kinase activity, but for cell death, the lectin domain was not needed. Silencing of the two closely related mitogen-activated protein kinase genes NbSIPK and NbNTF4 in N. benthamiana completely abolished LecRK-IX.1-induced cell death but not Phytophthora resistance. Liquid chromatography-mass spectrometry analysis of protein complexes coimmunoprecipitated in planta with LecRK-IX.1 or LecRK-IX.2 as bait, resulted in the identification of the N. benthamiana ABC transporter NbPDR1 as a potential interactor of both LecRK. The closest homolog of NbPDR1 in Arabidopsis is ABCG40, and coimmunoprecipitation experiments showed that ABCG40 associates with LecRK-IX.1 and LecRK-IX.2 in planta. Similar to the LecRK mutants, ABCG40 mutants showed compromised Phytophthora resistance. This study shows that LecRK-IX.1 and LecRK-IX.2 are Phytophthora resistance components that function independent of each other and independent of the cell-death phenotype. They both interact with the same ABC transporter, suggesting that they exploit similar signal transduction pathways.

  18. Star formation rate in Holmberg IX dwarf galaxy

    Directory of Open Access Journals (Sweden)

    Anđelić M.M.

    2011-01-01

    Full Text Available In this paper we use previously determined Hα fluxes for dwarf galaxy Holmberg IX (Arbutina et al. 2009 to calculate star formation rate (SFR in this galaxy. We discuss possible contaminations of Hα flux and, for the first time, we take into account optical emission from supernova remnants (SNRs as a possible source of contamination of Hα flux. Derived SFR for Holmberg IX is 3:4 x 10-4M.yr-1. Our value is lower then in previous studies, due to luminous shock-heated source M&H 9-10, possible hypernova remnant, which we excluded from the total Hα flux in our calculation of SFR.

  19. Growth stimulation of Porphyromonas endodontalis by hemoglobin and protoporphyrin IX.

    Science.gov (United States)

    Zerr, M A; Cox, C D; Johnson, W T; Drake, D R

    2000-12-01

    Porphyromonas endodontalis, like other Porphyromonas species, has a complex set of nutritional requirements. In addition to being an obligate anaerobe, the bacterium must be grown in a complex medium consisting of amino acids, reducing agents and heme compounds. P. endodontalis accumulates high concentrations of heme pigments to the extent that colonies appear black on blood agar. This accumulation of heme and the need for these compounds has been characterized as iron requirements by these species. However, in our studies, P. endodontalis demonstrated growth dependence on hemoglobin or protoporphyrin IX but not on free iron. Iron added to other heme compounds actually decreased growth stimulation by porphyrin-containing compounds. P. endodontalis actively transported free iron, but this process did not appear to be critical for growth. The maximum stimulation of growth by protoporphyrin IX, under conditions of iron deprivation, suggests that P. endodontalis requires the porphyrin moiety as a growth factor.

  20. Galaxy interactions and star formation: Results of a survey of global H-alpha emission in spiral galaxies in 8 clusters

    Science.gov (United States)

    Moss, C.

    1990-01-01

    Kennicutt and Kent (1983) have shown that the global H alpha emission from a spiral galaxy is an indicator of the formation rate of massive stars. Moss, Whittle and Irwin (1988) have surveyed two clusters (Abell 347 and 1367) for galaxies with H alpha emission using a high dispersion objective prism technique. The purpose of the survey is to investigate environmental effects on star formation in spiral galaxies, and in particular to ascertain whether star formation is enhanced in cluster spirals. Approximately 20 percent of CGCG galaxies were detected in emission. Two plates of excellent quality were obtained for each of the two clusters, and galaxies were only identified to have emission if this was detected on both plates of a plate pair. In this way, plate flaws and other spurious identifications of emission could be rejected, and weak emission confirmed. The results of this survey have been discussed by Moss (1987). The detected galaxies are of types SO-a and later. The frequency with which galaxies are detected in emission increases towards later morphological type as expected (cf. Kennicutt and Kent 1983). There is no evidence of any dependence of the frequency of detected emission on the absolute magnitude of the galaxy (cf. Moss and Whittle 1990), but there is a strong correlation between a disturbed morphological appearance of the galaxy and the detection of emission. Furthermore it is found that the emission is more centrally concentrated in those galaxies which show a disturbed morphology. It may be noted that the objective prism plate gives a spectrum of a 400 A region around rest wavelength H alpha, but superposed on this is the H alpha emission from the galaxy which, because the light is essentially monochromatic, results in a true two-dimensional image of the H alpha distribution. The visual appearance of the emission on the prism plates was classified according to its diffuseness on a 5 point scale (very diffuse, diffuse, intermediate, compact, and

  1. Motives and periods in Bianchi IX gravity models

    Science.gov (United States)

    Fan, Wentao; Fathizadeh, Farzad; Marcolli, Matilde

    2018-05-01

    We show that, when considering the anisotropic scaling factors and their derivatives as affine variables, the coefficients of the heat-kernel expansion of the Dirac-Laplacian on SU(2) Bianchi IX metrics are algebro-geometric periods of motives of complements in affine spaces of unions of quadrics and hyperplanes. We show that the motives are mixed Tate and we provide an explicit computation of their Grothendieck classes.

  2. Dark Energy Survey Year 1 Results: Methodology and Projections for Joint Analysis of Galaxy Clustering, Galaxy Lensing, and CMB Lensing Two-point Functions

    Energy Technology Data Exchange (ETDEWEB)

    Giannantonio, T.; et al.

    2018-02-14

    Optical imaging surveys measure both the galaxy density and the gravitational lensing-induced shear fields across the sky. Recently, the Dark Energy Survey (DES) collaboration used a joint fit to two-point correlations between these observables to place tight constraints on cosmology (DES Collaboration et al. 2017). In this work, we develop the methodology to extend the DES Collaboration et al. (2017) analysis to include cross-correlations of the optical survey observables with gravitational lensing of the cosmic microwave background (CMB) as measured by the South Pole Telescope (SPT) and Planck. Using simulated analyses, we show how the resulting set of five two-point functions increases the robustness of the cosmological constraints to systematic errors in galaxy lensing shear calibration. Additionally, we show that contamination of the SPT+Planck CMB lensing map by the thermal Sunyaev-Zel'dovich effect is a potentially large source of systematic error for two-point function analyses, but show that it can be reduced to acceptable levels in our analysis by masking clusters of galaxies and imposing angular scale cuts on the two-point functions. The methodology developed here will be applied to the analysis of data from the DES, the SPT, and Planck in a companion work.

  3. Use of modern contraceptives among married women in Vietnam: a multilevel analysis using the Multiple Indicator Cluster Survey (2011) and the Vietnam Population and Housing Census (2009).

    Science.gov (United States)

    Vu, Lan Thi Hoang; Oh, Juhwan; Bui, Quyen Thi-Tu; Le, Anh Thi-Kim

    2016-01-01

    The prevalence of modern contraceptive use is an important indicator that reflects accessibility to reproductive health services. Satisfying unmet needs for family planning alone could reduce the number of maternal deaths by almost a third. This study uses multiple data sources to examine multilevel factors associated with the use of modern contraceptives among married women in Vietnam aged 15-49 years. Data from different national surveys (Vietnam Population and Housing Census, Vietnam Living Standard Survey, and Multiple Indicator Cluster Survey) were linked to create a dataset including individual and contextual (provincial) variables (N=8,341). Multilevel modeling was undertaken to examine the impact of both individual and provincial characteristics on modern contraceptive use. Odds ratios (ORs) and 95% confidence intervals (CIs) are reported. Individual factors significantly associated with the use of modern contraceptives were age 30-34 years (reference 15-19 years) (OR=1.63); high socioeconomic status (SES) (OR=0.8); having two living children (OR=2.4); and having a son (OR=1.4). The provincial poverty rate mediated the association between the individual's SES and the likelihood of using modern contraceptives. The proportion of women in Vietnam using modern contraceptive methods has remained relatively high in recent years with significant variation across Vietnam's 63 provinces. Women of lower SES are more likely to use modern contraceptive methods, especially in the poorer provinces. Achieving access to universal reproductive health is one of the Millennium Development Goals. Vietnam must continue to make progress in this area.

  4. New polymorphic variants of human blood clotting factor IX

    Energy Technology Data Exchange (ETDEWEB)

    Surin, V.L.; Luk`yanenko, A.V.; Tagiev, A.F.; Smirnova, O.V. [Hematological Research Center, Moscow (Russian Federation); Plutalov, O.V.; Berlin, Yu.A. [Shemyakin Institute of Bioorganic Chemistry, Moscow (Russian Federation)

    1995-04-01

    The polymorphism of Alu-repeats, which are located in the introns of the human factor IX gene (copies 1-3), was studied. To identify polymorphic variants, direct sequencing of PCR products that contained appropriate repeats was used. In each case, 20 unrelated X chromosomes were studied. A polymorphic Dra I site was found near the 3{prime}-end of Alu copy 3 within the region of the polyA tract. A PCR-based testing system with internal control of restriction hydrolysis was suggested. Testing 81 unrelated X chromosomes revealed that the frequency of the polymorphic Dra I site is 0.23. Taq I polymorphism, which was revealed in Alu copy 4 of factor IX gene in our previous work, was found to be closely linked to Dra I polymorphism. Studies in linkage between different types of polymorphisms of the factor IX gene revealed the presence of a rare polymorphism in intron a that was located within the same minisatellite region as the known polymorphic insertion 50 bp/Dde I. However, the size of the insertion in our case was 26 bp. Only one polymorphic variant was found among over 150 unrelated X chromosomes derived from humans from Moscow and its vicinity. 10 refs., 4 figs., 1 tab.

  5. Loop quantum cosmology of Bianchi IX: effective dynamics

    International Nuclear Information System (INIS)

    Corichi, Alejandro; Montoya, Edison

    2017-01-01

    We study solutions to the effective equations for the Bianchi IX class of spacetimes within loop quantum cosmology (LQC). We consider Bianchi IX models whose matter content is a massless scalar field, by numerically solving the loop quantum cosmology effective equations, with and without inverse triad corrections. The solutions are classified using certain geometrically motivated classical observables. We show that both effective theories—with lapse N   =   V and N   =  1—resolve the big bang singularity and reproduce the classical dynamics far from the bounce. Moreover, due to the positive spatial curvature, there is an infinite number of bounces and recollapses. We study the limit of large field momentum and show that both effective theories reproduce the same dynamics, thus recovering general relativity. We implement a procedure to identify amongst the Bianchi IX solutions, those that behave like k   =  0,1 FLRW as well as Bianchi I, II, and VII 0 models. The effective solutions exhibit Bianchi I phases with Bianchi II transitions and also Bianchi VII 0 phases, which had not been studied before. We comment on the possible implications of these results for a quantum modification to the classical BKL behaviour. (paper)

  6. Spectral action for Bianchi type-IX cosmological models

    International Nuclear Information System (INIS)

    Fan, Wentao; Fathizadeh, Farzad; Marcolli, Matilde

    2015-01-01

    A rationality result previously proved for Robertson-Walker metrics is extended to a homogeneous anisotropic cosmological model, namely the Bianchi type-IX minisuperspace. It is shown that the Seeley-de Witt coefficients appearing in the expansion of the spectral action for the Bianchi type-IX geometry are expressed in terms of polynomials with rational coefficients in the cosmic evolution factors w_1(t),w_2(t),w_3(t), and their higher derivates with respect to time. We begin with the computation of the Dirac operator of this geometry and calculate the coefficients a_0,a_2,a_4 of the spectral action by using heat kernel methods and parametric pseudodifferential calculus. An efficient method is devised for computing the Seeley-de Witt coefficients of a geometry by making use of Wodzicki’s noncommutative residue, and it is confirmed that the method checks out for the cosmological model studied in this article. The advantages of the new method are discussed, which combined with symmetries of the Bianchi type-IX metric, yield an elegant proof of the rationality result.

  7. Loop quantum cosmology of Bianchi IX: effective dynamics

    Science.gov (United States)

    Corichi, Alejandro; Montoya, Edison

    2017-03-01

    We study solutions to the effective equations for the Bianchi IX class of spacetimes within loop quantum cosmology (LQC). We consider Bianchi IX models whose matter content is a massless scalar field, by numerically solving the loop quantum cosmology effective equations, with and without inverse triad corrections. The solutions are classified using certain geometrically motivated classical observables. We show that both effective theories—with lapse N  =  V and N  =  1—resolve the big bang singularity and reproduce the classical dynamics far from the bounce. Moreover, due to the positive spatial curvature, there is an infinite number of bounces and recollapses. We study the limit of large field momentum and show that both effective theories reproduce the same dynamics, thus recovering general relativity. We implement a procedure to identify amongst the Bianchi IX solutions, those that behave like k  =  0,1 FLRW as well as Bianchi I, II, and VII0 models. The effective solutions exhibit Bianchi I phases with Bianchi II transitions and also Bianchi VII0 phases, which had not been studied before. We comment on the possible implications of these results for a quantum modification to the classical BKL behaviour.

  8. Spectral action for Bianchi type-IX cosmological models

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Wentao; Fathizadeh, Farzad; Marcolli, Matilde [Division of Physics, Mathematics and Astronomy, California Institute of Technology,1200 E. California Blvd., Pasadena, CA 91125 (United States)

    2015-10-13

    A rationality result previously proved for Robertson-Walker metrics is extended to a homogeneous anisotropic cosmological model, namely the Bianchi type-IX minisuperspace. It is shown that the Seeley-de Witt coefficients appearing in the expansion of the spectral action for the Bianchi type-IX geometry are expressed in terms of polynomials with rational coefficients in the cosmic evolution factors w{sub 1}(t),w{sub 2}(t),w{sub 3}(t), and their higher derivates with respect to time. We begin with the computation of the Dirac operator of this geometry and calculate the coefficients a{sub 0},a{sub 2},a{sub 4} of the spectral action by using heat kernel methods and parametric pseudodifferential calculus. An efficient method is devised for computing the Seeley-de Witt coefficients of a geometry by making use of Wodzicki’s noncommutative residue, and it is confirmed that the method checks out for the cosmological model studied in this article. The advantages of the new method are discussed, which combined with symmetries of the Bianchi type-IX metric, yield an elegant proof of the rationality result.

  9. Effect of 5-aminolevulinic acid on kinetics of protoporphyrin IX production in CHO cells.

    Directory of Open Access Journals (Sweden)

    W Warchoł

    2004-07-01

    Full Text Available 5-aminolevulinic acid (ALA is utilized in a photodynamic therapy as a compound capable of augmenting intracellular pool of protoporphyrin IX (PpIX, which exhibits properties of a photosensitizer. The studies were aimed at monitoring accumulation of endogenous protoporphyrin IX in CHO cells under effect of various concentrations of ALA in culture medium and following removal of the compound from the culture medium. Cell content of PpIX was determined following incubation of the cells for 72 h in a culture medium containing different concentration of ALA. Moreover, the cells were preincubated for 2 h in ALA at various concentrations and separated from the compound by medium change and their PpIX content was monitored following incubation. PpIX content was defined by a fluorescent technique under the confocal microscope. In the course of continuous incubation of cells with ALA, biphasic alterations were noted in cellular PpIX concentration. Removal of ALA from the incubation medium resulted at first in a decrease in PpIX content in cells, which was followed by an evidently augmented accumulation of the compound in the cells. The results suggested that in the case of CHO cells, exogenous ALA was not an exclusive source of PpIX synthesis and that alterations in enzyme activities were responsible for production of PpIX.

  10. Phosphorylation of carbonic anhydrase IX controls its ability to mediate extracellular acidification in hypoxic tumors.

    Science.gov (United States)

    Ditte, Peter; Dequiedt, Franck; Svastova, Eliska; Hulikova, Alzbeta; Ohradanova-Repic, Anna; Zatovicova, Miriam; Csaderova, Lucia; Kopacek, Juraj; Supuran, Claudiu T; Pastorekova, Silvia; Pastorek, Jaromir

    2011-12-15

    In the hypoxic regions of a tumor, carbonic anhydrase IX (CA IX) is an important transmembrane component of the pH regulatory machinery that participates in bicarbonate transport. Because tumor pH has implications for growth, invasion, and therapy, determining the basis for the contributions of CA IX to the hypoxic tumor microenvironment could lead to new fundamental and practical insights. Here, we report that Thr443 phosphorylation at the intracellular domain of CA IX by protein kinase A (PKA) is critical for its activation in hypoxic cells, with the fullest activity of CA IX also requiring dephosphorylation of Ser448. PKA is activated by cAMP, which is elevated by hypoxia, and we found that attenuating PKA in cells disrupted CA IX-mediated extracellular acidification. Moreover, following hypoxia induction, CA IX colocalized with the sodium-bicarbonate cotransporter and other PKA substrates in the leading edge membranes of migrating tumor cells, in support of the concept that bicarbonate metabolism is spatially regulated at cell surface sites with high local ion transport and pH control. Using chimeric CA IX proteins containing heterologous catalytic domains derived from related CA enzymes, we showed that CA IX activity was modulated chiefly by the intracellular domain where Thr443 is located. Our findings indicate that CA IX is a pivotal mediator of the hypoxia-cAMP-PKA axis, which regulates pH in the hypoxic tumor microenvironment.

  11. The Hubble Space Telescope UV Legacy Survey of Galactic globular clusters - XIV. Multiple stellar populations within M 15 and their radial distribution

    Science.gov (United States)

    Nardiello, D.; Milone, A. P.; Piotto, G.; Anderson, J.; Bedin, L. R.; Bellini, A.; Cassisi, S.; Libralato, M.; Marino, A. F.

    2018-06-01

    In the context of the Hubble Space Telescope UV Survey of Galactic globular clusters (GCs), we derived high-precision, multi-band photometry to investigate the multiple stellar populations in the massive and metal-poor GC M 15. By creating for red-giant branch (RGB) stars of the cluster a `chromosome map', which is a pseudo two-colour diagram made with appropriate combination of F275W, F336W, F438W, and F814W magnitudes, we revealed colour spreads around two of the three already known stellar populations. These spreads cannot be produced by photometric errors alone and could hide the existence of (two) additional populations. This discovery increases the complexity of the multiple-population phenomenon in M 15. Our analysis shows that M 15 exhibits a faint sub-giant branch (SGB), which is also detected in colour-magnitude diagrams (CMDs) made with optical magnitudes only. This poorly populated SGB includes about 5 per cent of the total number of SGB stars and evolves into a red RGB in the mF336W versus mF336W - mF814W CMD, suggesting that M 15 belongs to the class of Type II GCs. We measured the relative number of stars in each population at various radial distances from the cluster centre, showing that all of these populations share the same radial distribution within statistic uncertainties. These new findings are discussed in the context of the formation and evolution scenarios of the multiple populations.

  12. 3D galaxy clustering with future wide-field surveys: Advantages of a spherical Fourier-Bessel analysis

    Science.gov (United States)

    Lanusse, F.; Rassat, A.; Starck, J.-L.

    2015-06-01

    Context. Upcoming spectroscopic galaxy surveys are extremely promising to help in addressing the major challenges of cosmology, in particular in understanding the nature of the dark universe. The strength of these surveys, naturally described in spherical geometry, comes from their unprecedented depth and width, but an optimal extraction of their three-dimensional information is of utmost importance to best constrain the properties of the dark universe. Aims: Although there is theoretical motivation and novel tools to explore these surveys using the 3D spherical Fourier-Bessel (SFB) power spectrum of galaxy number counts Cℓ(k,k'), most survey optimisations and forecasts are based on the tomographic spherical harmonics power spectrum C(ij)_ℓ. The goal of this paper is to perform a new investigation of the information that can be extracted from these two analyses in the context of planned stage IV wide-field galaxy surveys. Methods: We compared tomographic and 3D SFB techniques by comparing the forecast cosmological parameter constraints obtained from a Fisher analysis. The comparison was made possible by careful and coherent treatment of non-linear scales in the two analyses, which makes this study the first to compare 3D SFB and tomographic constraints on an equal footing. Nuisance parameters related to a scale- and redshift-dependent galaxy bias were also included in the computation of the 3D SFB and tomographic power spectra for the first time. Results: Tomographic and 3D SFB methods can recover similar constraints in the absence of systematics. This requires choosing an optimal number of redshift bins for the tomographic analysis, which we computed to be N = 26 for zmed ≃ 0.4, N = 30 for zmed ≃ 1.0, and N = 42 for zmed ≃ 1.7. When marginalising over nuisance parameters related to the galaxy bias, the forecast 3D SFB constraints are less affected by this source of systematics than the tomographic constraints. In addition, the rate of increase of the

  13. SPITZER ULTRA FAINT SURVEY PROGRAM (SURFS UP). II. IRAC-DETECTED LYMAN-BREAK GALAXIES AT 6 ≲ z ≲ 10 BEHIND STRONG-LENSING CLUSTERS

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Kuang-Han; Bradač, Maruša; Hoag, Austin; Cain, Benjamin; Lubin, L. M.; Knight, Robert I. [University of California Davis, 1 Shields Avenue, Davis, CA 95616 (United States); Lemaux, Brian C. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Ryan, R. E. Jr.; Brammer, Gabriel B. [Aix Marseille Université, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France); Castellano, Marco; Amorin, Ricardo; Fontana, Adriano; Merlin, Emiliano [INAF—Osservatorio Astronomico di Roma Via Frascati 33, I-00040 Monte Porzio Catone (Italy); Schmidt, Kasper B. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Schrabback, Tim [Argelander-Institut für Astronomie, Auf Dem Hügel 71, D-53121 Bonn (Germany); Treu, Tommaso [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095 (United States); Gonzalez, Anthony H. [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Linden, Anja von der, E-mail: khhuang@ucdavis.edu, E-mail: astrokuang@gmail.com [Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, CA 94305 (United States)

    2016-01-20

    We study the stellar population properties of the IRAC-detected 6 ≲ z ≲ 10 galaxy candidates from the Spitzer UltRa Faint SUrvey Program. Using the Lyman Break selection technique, we find a total of 17 galaxy candidates at 6 ≲ z ≲ 10 from Hubble Space Telescope images (including the full-depth images from the Hubble Frontier Fields program for MACS 1149 and MACS 0717) that have detections at signal-to-noise ratios  ≥ 3 in at least one of the IRAC 3.6 and 4.5 μm channels. According to the best mass models available for the surveyed galaxy clusters, these IRAC-detected galaxy candidates are magnified by factors of ∼1.2–5.5. Due to the magnification of the foreground galaxy clusters, the rest-frame UV absolute magnitudes M{sub 1600} are between −21.2 and −18.9 mag, while their intrinsic stellar masses are between 2 × 10{sup 8}M{sub ⊙} and 2.9 × 10{sup 9}M{sub ⊙}. We identify two Lyα emitters in our sample from the Keck DEIMOS spectra, one at z{sub Lyα} = 6.76 (in RXJ 1347) and one at z{sub Lyα} = 6.32 (in MACS 0454). We find that 4 out of 17 z ≳ 6 galaxy candidates are favored by z ≲ 1 solutions when IRAC fluxes are included in photometric redshift fitting. We also show that IRAC [3.6]–[4.5] color, when combined with photometric redshift, can be used to identify galaxies which likely have strong nebular emission lines or obscured active galactic nucleus contributions within certain redshift windows.

  14. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: constraining modified gravity

    Science.gov (United States)

    Mueller, Eva-Maria; Percival, Will; Linder, Eric; Alam, Shadab; Zhao, Gong-Bo; Sánchez, Ariel G.; Beutler, Florian; Brinkmann, Jon

    2018-04-01

    We use baryon acoustic oscillation and redshift space distortion from the completed Baryon Oscillation Spectroscopic Survey, corresponding to Data Release 12 of the Sloan Digital Sky Survey, combined sample analysis in combination with cosmic microwave background, supernova, and redshift space distortion measurements from additional spectroscopic surveys to test deviations from general relativity. We present constraints on several phenomenological models of modified gravity: First, we parametrize the growth of structure using the growth index γ, finding γ = 0.566 ± 0.058 (68 per cent C.L.). Secondly, we modify the relation of the two Newtonian potentials by introducing two additional parameters, GM and GL. In this approach, GM refers to modifications of the growth of structure whereas GL to modification of the lensing potential. We consider a power law to model the redshift dependence of GM and GL as well as binning in redshift space, introducing four additional degrees of freedom, GM(z 0.5), GL(z 0.5). At 68 per cent C.L., we measure GM = 0.980 ± 0.096 and GL = 1.082 ± 0.060 for a linear model, GM = 1.01 ± 0.36 and GL = 1.31 ± 0.19 for a cubic model as well as GM(z 0.5) = 0.986 ± 0.022, GL(z 0.5) = 1.037 ± 0.029. Thirdly, we investigate general scalar tensor theories of gravity, finding the model to be mostly unconstrained by current data. Assuming a one-parameter f(R) model, we can constrain B0 < 7.7 × 10-5 (95 per cent C.L). For all models we considered, we find good agreement with general relativity.

  15. Uncertainty in the visibility mask of a survey and its effects on the clustering of biased tracers

    Energy Technology Data Exchange (ETDEWEB)

    Colavincenzo, M.; Monaco, P.; Borgani, S. [Dipartimento di Fisica, Università di Trieste, via G.B. Tiepolo 11, I-34131 Trieste (Italy); Sefusatti, E., E-mail: colavincenzo@oats.inaf.it, E-mail: monaco@oats.inaf.it, E-mail: emiliano.sefusatti@brera.inaf.it, E-mail: borgani@oats.inaf.it [INAF—Osservatorio Astronomico di Brera, via E. Bianchi 46, I-23807 Merate (Italy)

    2017-03-01

    The forecasted accuracy of upcoming surveys of large-scale structure cannot be achieved without a proper quantification of the error induced by foreground removal (or other systematics like 0-point photometry offset). Because these errors are highly correlated on the sky, their influence is expected to be especially important at very large scales, at and beyond the first Baryonic Acoustic Oscillation (BAO). In this work we quantify how the uncertainty in the visibility mask of a survey, that gives the survey depth in a specific sky area, influences the measured power spectrum of a sample of tracers of the density field and its covariance matrix. We start from a very large set of 10,000 catalogs of dark matter (DM) halos in periodic cosmological boxes, produced with the PINOCCHIO approximate method. To make an analytic approach feasible, we assume luminosity-independent halo bias and an idealized geometry for the visibility mask, that is constant in square tiles of physical length l ; this should be interpreted as the projection, at the observation redshift, of the angular correlation scale of the foreground residuals. We find that the power spectrum of these biased tracers can be expressed as the sum of a cosmological term, a mask term and a term involving their convolution. The mask and convolution terms scale like P ∝ l {sup 2}σ {sub A} {sup 2}, where σ {sub A} {sup 2} is the variance of the uncertainty on the visibility mask. With l = 30−100 Mpc/ h and σ {sub A} = 5−20%, the mask term can be significant at k ∼ 0.01−0.1 h /Mpc, and the convolution term can amount to ∼ 1−10% of the total. The influence of mask uncertainty on power spectrum covariance is more complicated: the coupling of the convolution term with the other two gives rise to several mixed terms, that we quantify by difference using the mock catalogs. These are found to be of the same order of the mask covariance, and to introduce non-diagonal terms at large scales. As a consequence

  16. The Canada-France deep fields survey-II: Lyman-break galaxies and galaxy clustering at z ~ 3

    Science.gov (United States)

    Foucaud, S.; McCracken, H. J.; Le Fèvre, O.; Arnouts, S.; Brodwin, M.; Lilly, S. J.; Crampton, D.; Mellier, Y.

    2003-10-01

    We present a large sample of z ~ 3 U-band dropout galaxies extracted from the Canada-France deep fields survey (CFDF). Our catalogue covers an effective area of ~ 1700 arcmin2 divided between three large, contiguous fields separated widely on the sky. To IAB=24.5, the survey contains 1294 Lyman-break candidates, in agreement with previous measurements by other authors, after appropriate incompleteness corrections have been applied to our data. Based on comparisons with spectroscopic observations and simulations, we estimate that our sample of Lyman-break galaxies is contaminated by stars and interlopers (lower-redshift galaxies) at no more than { ~ } 30%. We find that omega (theta ) is well fitted by a power-law of fixed slope, gamma =1.8, even at small (theta University of Hawaii, and at the Cerro Tololo Inter-American Observatory and Mayall 4-meter Telescopes, divisions of the National Optical Astronomy Observatories, which are operated by the Association of Universities for Research in Astronomy, Inc. under cooperative agreement with the National Science Foundation.

  17. Molecular phylogeny and intricate evolutionary history of the three isofunctional enzymes involved in the oxidation of protoporphyrinogen IX.

    Science.gov (United States)

    Kobayashi, Koichi; Masuda, Tatsuru; Tajima, Naoyuki; Wada, Hajime; Sato, Naoki

    2014-08-01

    Tetrapyrroles such as heme and chlorophyll are essential for biological processes, including oxygenation, respiration, and photosynthesis. In the tetrapyrrole biosynthesis pathway, protoporphyrinogen IX oxidase (Protox) catalyzes the formation of protoporphyrin IX, the last common intermediate for the biosynthesis of heme and chlorophyll. Three nonhomologous isofunctional enzymes, HemG, HemJ, and HemY, for Protox have been identified. To reveal the distribution and evolution of the three Protox enzymes, we identified homologs of each along with other heme biosynthetic enzymes by whole-genome clustering across three domains of life. Most organisms possess only one of the three Protox types, with some exceptions. Detailed phylogenetic analysis revealed that HemG is mostly limited to γ-Proteobacteria whereas HemJ may have originated within α-Proteobacteria and transferred to other Proteobacteria and Cyanobacteria. In contrast, HemY is ubiquitous in prokaryotes and is the only Protox in eukaryotes, so this type may be the ancestral Protox. Land plants have a unique HemY homolog that is also shared by Chloroflexus species, in addition to the main HemY homolog originating from Cyanobacteria. Meanwhile, organisms missing any Protox can be classified into two groups; those lacking most heme synthetic genes, which necessarily depend on external heme supply, and those lacking only genes involved in the conversion of uroporphyrinogen III into heme, which would use a precorrin2-dependent alternative pathway. However, hemN encoding coproporphyrinogen IX oxidase was frequently found in organisms lacking Protox enzyme, which suggests a unique role of this gene other than in heme biosynthesis. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  18. VEGAS-SSS. II. Comparing the globular cluster systems in NGC 3115 and NGC 1399 using VEGAS and FDS survey data. The quest for a common genetic heritage of globular cluster systems

    Science.gov (United States)

    Cantiello, Michele; D'Abrusco, Raffaele; Spavone, Marilena; Paolillo, Maurizio; Capaccioli, Massimo; Limatola, Luca; Grado, Aniello; Iodice, Enrica; Raimondo, Gabriella; Napolitano, Nicola; Blakeslee, John P.; Brocato, Enzo; Forbes, Duncan A.; Hilker, Michael; Mieske, Steffen; Peletier, Reynier; van de Ven, Glenn; Schipani, Pietro

    2018-04-01

    We analyze the globular cluster (GC) systems in two very different galaxies, NGC 3115 and NGC 1399. With the papers of this series, we aim at highlighting common and different properties in the GC systems in galaxies covering a wide range of parameter space. We compare the GCs in NGC 3115 and NGC 1399 as derived from the analysis of one square degree u-, g-, and i-band images taken with the VST telescope as part of the VST early-type galaxy survey (VEGAS) and Fornax deep survey (FDS). We selected GC candidates using as reference the morpho-photometric and color properties of confirmed GCs. The surface density maps of GCs in NGC 3115 reveal a morphology similar to the light profile of field stars; the same is true when blue and red GCs are taken separately. The GC maps for NGC 1399 are richer in structure and confirm the existence of an intra-cluster GC component. We confirm the presence of a spatial offset in the NGC 1399 GC centroid and find that the centroid of the GCs for NGC 3115 coincides well with the galaxy center. Both GC systems show unambiguous color bimodality in (g - i) and (u - i); the color-color relations of the two GC systems are slightly different with NGC 3115 appearing more linear than NGC 1399. The azimuthal average of the radial density profiles in both galaxies reveals a larger spatial extent for the total GCs population with respect to the galaxy surface brightness profile. For both galaxies, the red GCs have radial density profiles compatible with the galaxy light profile, while the radial profiles for blue GCs are shallower. As for the specific frequency of GCs, SN, we find it is a factor of two higher in NGC 1399 than for NGC 3115; this is mainly the result of extra blue GCs. By inspecting the radial behavior of the specific frequency, SN(

  19. The MAVERIC Survey: A Red Straggler Binary with an Invisible Companion in the Galactic Globular Cluster M10

    Science.gov (United States)

    Shishkovsky, Laura; Strader, Jay; Chomiuk, Laura; Bahramian, Arash; Tremou, Evangelia; Li, Kwan-Lok; Salinas, Ricardo; Tudor, Vlad; Miller-Jones, James C. A.; Maccarone, Thomas J.; Heinke, Craig O.; Sivakoff, Gregory R.

    2018-03-01

    We present the discovery and characterization of a radio-bright binary in the Galactic globular cluster M10. First identified in deep radio continuum data from the Karl G. Jansky Very Large Array, M10-VLA1 has a flux density of 27 ± 4 μJy at 7.4 GHz and a flat-to-inverted radio spectrum. Chandra imaging shows an X-ray source with L X ≈ 1031 erg s‑1 matching the location of the radio source. This places M10-VLA1 within the scatter of the radio-X-ray luminosity correlation for quiescent stellar-mass black holes, and a black hole X-ray binary is a viable explanation for this system. The radio and X-ray properties of the source disfavor, but do not rule out, identification as an accreting neutron star or white dwarf system. Optical imaging from the Hubble Space Telescope and spectroscopy from the SOAR telescope show that the system has an orbital period of 3.339 days and an unusual “red straggler” component: an evolved star found redward of the M10 red giant branch. These data also show UV/optical variability and double-peaked Hα emission characteristic of an accretion disk. However, SOAR spectroscopic monitoring reveals that the velocity semi-amplitude of the red straggler is low. We conclude that M10-VLA1 is most likely either a quiescent black hole X-ray binary with a rather face-on (i orientation or an unusual flaring RS Canum Venaticorum variable-type active binary, and discuss future observations that could distinguish between these possibilities.

  20. The Structure of Carbonic Anhydrase IX Is Adapted for Low-pH Catalysis.

    Science.gov (United States)

    Mahon, Brian P; Bhatt, Avni; Socorro, Lilien; Driscoll, Jenna M; Okoh, Cynthia; Lomelino, Carrie L; Mboge, Mam Y; Kurian, Justin J; Tu, Chingkuang; Agbandje-McKenna, Mavis; Frost, Susan C; McKenna, Robert

    2016-08-23

    Human carbonic anhydrase IX (hCA IX) expression in many cancers is associated with hypoxic tumors and poor patient outcome. Inhibitors of hCA IX have been used as anticancer agents with some entering Phase I clinical trials. hCA IX is transmembrane protein whose catalytic domain faces the extracellular tumor milieu, which is typically associated with an acidic microenvironment. Here, we show that the catalytic domain of hCA IX (hCA IX-c) exhibits the necessary biochemical and biophysical properties that allow for low pH stability and activity. Furthermore, the unfolding process of hCA IX-c appears to be reversible, and its catalytic efficiency is thought to be correlated directly with its stability between pH 3.0 and 8.0 but not above pH 8.0. To rationalize this, we determined the X-ray crystal structure of hCA IX-c to 1.6 Å resolution. Insights from this study suggest an understanding of hCA IX-c stability and activity in low-pH tumor microenvironments and may be applicable to determining pH-related effects on enzymes.

  1. Embryonic chicken cornea and cartilage synthesize type IX collagen molecules with different amino-terminal domains.

    OpenAIRE

    Svoboda, K K; Nishimura, I; Sugrue, S P; Ninomiya, Y; Olsen, B R

    1988-01-01

    We have analyzed embryonic chicken cornea for the presence of type IX collagen mRNA and protein. Using RNA transfer blot analysis, we demonstrate that alpha 1(IX) and alpha 2(IX) mRNAs are expressed by corneal epithelial cells at the time that the primary stromal components are synthesized. The levels of the mRNAs decrease with increasing developmental age and are barely detectable at day 11 of development. In contrast, type IX collagen protein is detectable by immunofluorescence at days 5 an...

  2. The spectroscopy analyses of PpIX by ultrasound irradiation and its sonotoxicity in vitro.

    Science.gov (United States)

    Wang, Pan; Wang, Xiaobing; Zhang, Kun; Gao, Kaili; Song, Ming; Liu, Quanhong

    2013-07-01

    Protoporphyrin IX (PpIX) has been used as a sensitizer in photodynamic therapy (PDT) as well as in sonodynamic therapy (SDT). The photo-bleaching of PpIX has been well investigated in many experimental systems and some photo-products have also been identified in PDT. But until now, little information has been reported about the sono-damage of PpIX in SDT. So, the present study was to investigate changes of PpIX properties before and after different ultrasound treatment, and the potential interactions between PpIX, ultrasound and the irradiated cells. In cell-free system, the absorption and fluorescence spectra of PpIX in different solutions were measured by ultraviolet spectrometer and fluorescence spectrophotometer, respectively. The terephthalic acid dosimetry was applied to evaluate the efficiency of ultrasound cavitation by monitoring hydroxyl radical (OH) production on the thermolysis of H2O in the ultrasound field. In in vitro study, confocal microscopy was applied to detect the sub-cellular localization of PpIX in S180 cells before and after ultrasound exposure. Flow cytometry was used to detect the reactive oxygen species (ROS) generation during PpIX-SDT. MTT assay was performed to evaluate the cell viability of S180 cells after SDT treatment with or without ROS scavengers. The results show that PpIX displayed different spectral patterns in different solutions. PpIX was decomposed by ultrasound exposure as measured by the decreased absorption and fluorescence peak values in RPMI-1640 medium. In addition, the decomposition of PpIX was found to be simultaneously accompanied by OH production with increasing output power from ultrasound generator. PpIX at 1μg/ml significantly enhanced the ultrasound induced cavitation as measured by OH generation, and which was greatly eliminated by NaN3, histidine, mannitol, EDTA and catalase, but not by SOD. The in vitro study indicates more PpIX entered into S180 cells after ultrasound exposure. And, the extra-cellular PpIX

  3. Noninvasive murine glioma detection improved following photobleaching of skin PpIX fluorescence

    Science.gov (United States)

    Gibbs-Strauss, Summer L.; Davis, Scott C.; O'Hara, Julia A.; Hoopes, P. Jack; Hasan, Tayyaba; Pogue, Brian W.

    2008-02-01

    Aminolevulinic Acid (ALA) is a prodrug which can be administered to cells, animals or patients after which it is transformed via the Heme synthesis pathway into the fluorescent molecule Protoporphyrin IX (PpIX). PpIX has been shown to be useful as both a photosensitizer for photodynamic therapy (PDT) and as a fluorescence imaging contrast agent. The ALA-PpIX system not only provides contrast for fluorescence imaging but also gives information about the metabolic activity of the imaged tissue and thus could be useful for monitoring cancer therapy. In the current study skin photobleaching was examined to determine if PpIX fluorescence contrast in malignant brain tumors could be better visualized noninvasively. Red light photobleaching decreased skin PpIX fluorescence and increased the ability to noninvasively quantify PpIX fluorescence in murine gliomas, as in vivo measurements of mean PpIX fluorescence more closely matched ex vivo quantification following skin photobleaching. Three doses of blue light photobleaching (4 J/cm2, 8 J/cm2 and 12 J/cm2) were tested and determined to give similar levels of skin photobleaching as well as a similar window of decreased skin PpIX fluorescence for noninvasive fluorescence imaging following the photobleaching dose administration.

  4. Variability of in vivo recovery of factor IX after infusion of monoclonal antibody purified factor IX concentrates in patients with hemophilia B. The Mononine Study Group.

    Science.gov (United States)

    White, G C; Shapiro, A D; Kurczynski, E M; Kim, H C; Bergman, G E

    1995-05-01

    Monoclonal antibody purified factor IX concentrate, Mononine (Armour Pharmaceutical Company, Kankakee, Illinois, USA), is a recently developed replacement factor concentrate for the treatment of patients with hemophilia B. The pharmacokinetic properties of monoclonal antibody purified factor IX concentrate (MAb Factor IX concentrate) have been evaluated in only small samples of patients, and little is known about those factors that might influenced in vivo recovery of factor IX after infusion is a larger patient population. In vivo recovery of factor IX was therefore evaluated for 80 different indications in 72 patients who received MAb Factor IX concentrate for the management of spontaneous or trauma-induced bleeding, or as prophylaxis with surgery. The average recovery after infusions for presurgical pharmacokinetic analysis (mean +/- standard deviation) was 1.28 +/- 0.56 U/dl rise per U/kg infused (range 0.41-2.80), and the average recovery after all infusions for treatment was 1.23 +/- 0.49 U/dl rise per U/kg infused (range - 0.35-2.92). Recovery values for multiple MAb Factor IX doses in a given patient were also variable; the average recovery was 1.22 +/- 0.53 U/dl rise per U/kg given, and standard deviations ranged from 0.03 to 1.26. Patient age, weight, and MAb Factor IX concentrate dose minimally but significantly influenced factor IX recovery. There was no significant effect of either race, history of previous thrombotic complications during treatment with other replacement factor concentrates, or bleeding state on recovery. All of the patients treated with this preparation experienced excellent hemostasis, and no thrombotic complications were observed.

  5. Comparing Dark Energy Survey and HST –CLASH observations of the galaxy cluster RXC J2248.7-4431: implications for stellar mass versus dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Palmese, A.; Lahav, O.; Banerji, M.; Gruen, D.; Jouvel, S.; Melchior, P.; Aleksić, J.; Annis, J.; Diehl, H. T.; Hartley, W. G.; Jeltema, T.; Romer, A. K.; Rozo, E.; Rykoff, E. S.; Seitz, S.; Suchyta, E.; Zhang, Y.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Crocce, M.; Cunha, C. E.; D' Andrea, C. B.; da Costa, L. N.; Desai, S.; Dietrich, J. P.; Doel, P.; Estrada, J.; Evrard, A. E.; Flaugher, B.; Frieman, J.; Gerdes, D. W.; Goldstein, D. A.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Li, T. S.; Lima, M.; Maia, M. A. G.; Marshall, J. L.; Miller, C. J.; Miquel, R.; Nord, B.; Ogando, R.; Plazas, A. A.; Roodman, A.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Tucker, D.; Vikram, V.

    2016-08-20

    We derive the stellar mass fraction in the galaxy cluster RXC J2248.7-4431 observed with the Dark Energy Survey (DES) during the Science Verification period. We compare the stellar mass results from DES (five filters) with those from the Hubble Space Telescope Cluster Lensing And Supernova Survey (CLASH; 17 filters). When the cluster spectroscopic redshift is assumed, we show that stellar masses from DES can be estimated within 25 per cent of CLASH values. We compute the stellar mass contribution coming from red and blue galaxies, and study the relation between stellar mass and the underlying dark matter using weak lensing studies with DES and CLASH. An analysis of the radial profiles of the DES total and stellar mass yields a stellar-to-total fraction of f(star) = (6.8 +/- 1.7) x 10(-3) within a radius of r(200c) similar or equal to 2 Mpc. Our analysis also includes a comparison of photometric redshifts and star/galaxy separation efficiency for both data sets. We conclude that space-based small field imaging can be used to calibrate the galaxy properties in DES for the much wider field of view. The technique developed to derive the stellar mass fraction in galaxy clusters can be applied to the similar to 100 000 clusters that will be observed within this survey and yield important information about galaxy evolution.

  6. HST Grism Confirmation of 16 Structures at 1.4 < z < 2.8 from the Clusters Around Radio-Loud AGN (CARLA) Survey

    Science.gov (United States)

    Noirot, Gaël; Stern, Daniel; Mei, Simona; Wylezalek, Dominika; Cooke, Elizabeth A.; De Breuck, Carlos; Galametz, Audrey; Hatch, Nina A.; Vernet, Joël; Brodwin, Mark; Eisenhardt, Peter; Gonzalez, Anthony H.; Jarvis, Matt; Rettura, Alessandro; Seymour, Nick; Stanford, S. A.

    2018-05-01

    We report spectroscopic results from our 40-orbit Hubble Space Telescope slitless grism spectroscopy program observing the 20 densest Clusters Around Radio-Loud AGN (CARLA) candidate galaxy clusters at 1.4 targeting 420 distant radio-loud AGN. We report the spectroscopic confirmation of 16 distant structures at 1.4 targeted powerful high-redshift radio-loud AGN. We also report the serendipitous discovery and spectroscopic confirmation of seven additional structures at 0.87 targeted radio-loud AGN. We find that 1010–1011 M ⊙ member galaxies of our confirmed CARLA structures form significantly fewer stars than their field counterparts at all redshifts within 1.4 ≤ z ≤ 2. We also observe higher star-forming activity in the structure cores up to z = 2, finding similar trends as cluster surveys at slightly lower redshifts (1.0 strategy of obtaining just two grism orbits per field only obtains spectroscopic confirmation of emission line galaxies. Deeper spectroscopy will be required to study the population of evolved, massive galaxies in these (forming) clusters. Lacking multi-band coverage of the fields, we adopt a very conservative approach of calling all confirmations “structures,” although we note that a number of features are consistent with some of them being bona fide galaxy clusters. Together this survey represents a unique and large homogenous sample of spectroscopically confirmed structures at high redshifts, potentially more than doubling the census of confirmed, massive clusters at z > 1.4.

  7. Mental health and psychosocial problems in the aftermath of the Nepal earthquakes: findings from a representative cluster sample survey.

    Science.gov (United States)

    Kane, J C; Luitel, N P; Jordans, M J D; Kohrt, B A; Weissbecker, I; Tol, W A

    2018-06-01

    Two large earthquakes in 2015 caused widespread destruction in Nepal. This study aimed to examine frequency of common mental health and psychosocial problems and their correlates following the earthquakes. A stratified multi-stage cluster sampling design was employed to randomly select 513 participants (aged 16 and above) from three earthquake-affected districts in Nepal: Kathmandu, Gorkha and Sindhupalchowk, 4 months after the second earthquake. Outcomes were selected based on qualitative preparatory research and included symptoms of depression and anxiety (Hopkins Symptom Checklist-25); post-traumatic stress disorder (PTSD Checklist-Civilian); hazardous alcohol use (AUDIT-C); symptoms indicating severe psychological distress (WHO-UNHCR Assessment Schedule of Serious Symptoms in Humanitarian Settings (WASSS)); suicidal ideation (Composite International Diagnostic Interview); perceived needs (Humanitarian Emergency Settings Perceived Needs Scale (HESPER)); and functional impairment (locally developed scale). A substantial percentage of participants scored above validated cut-off scores for depression (34.3%, 95% CI 28.4-40.4) and anxiety (33.8%, 95% CI 27.6-40.6). Hazardous alcohol use was reported by 20.4% (95% CI 17.1-24.3) and 10.9% (95% CI 8.8-13.5) reported suicidal ideation. Forty-two percent reported that 'distress' was a serious problem in their community. Anger that was out of control (symptom from the WASSS) was reported by 33.7% (95% CI 29.5-38.2). Fewer people had elevated rates of PTSD symptoms above a validated cut-off score (5.2%, 95% CI 3.9-6.8), and levels of functional impairment were also relatively low. Correlates of elevated symptom scores were female gender, lower caste and greater number of perceived needs. Residing in Gorkha and Sindhupalchowk districts and lower caste were also associated with greater perceived needs. Higher levels of impaired functioning were associated with greater odds of depression and anxiety symptoms; impaired

  8. Immunosuppressive effects of factor IX products: an in vitro study.

    Science.gov (United States)

    Grosset, A B; McGregor, J R; Samlowski, W E; Rodgers, G M

    1999-11-01

    The effects of a recombinant factor IX product (BeneFix), and of five plasma-derived factor IX products, AlphaNine, Immunine, Konyne, Mononine and Replinine on in vitro peripheral blood mononuclear cell (PBMC) immune function were compared in a blinded study. We assessed the effects of these products on Con-A-induced lymphocyte proliferation and interleukin-2 and interleukin-10 secretion, expression of lymphocyte activation markers, and nitric oxide secretion by stimulated mouse peritoneal macrophages. At 1 mL-1 for 48 h, Konyne reduced Con-A-induced mitogenesis by 50% (P < 0.05); AlphaNine, Mononine and BeneFix had no effect. At 10 IU mL-1, Con-A-induced mi- togenesis was at control levels with Mononine and BeneFix, but was reduced to <15% (P < 0.05) with each of the other products. IL-2 and IL-10 secretion by Con-A-stimulated lymphocytes was also markedly depressed by all the products tested except Mononine and BeneFix. Dialysis of these products did not substantially affect these results. Flow cytometric analysis of lymphocyte activation markers following Con-A stimulation showed that Konyne also decreased IL-2 receptor alpha and beta chain (CD25 and CD122) induction on PBMC. Konyne also inhibited nitric oxide secretion to levels <18% of controls. These results indicate that certain factor IX products, including some of purported higher purity, substantially depress in vitro immune function. The importance of these findings to in vivo immune function in haemophilia B patients remains to be established.

  9. Fe IX CALCULATIONS FOR THE SOLAR DYNAMICS OBSERVATORY

    International Nuclear Information System (INIS)

    Foster, Adam R.; Testa, Paola

    2011-01-01

    New calculations of the energy levels, radiative transition rates, and collisional excitation rates of Fe IX have been carried out using the Flexible Atomic Code, paying close attention to experimentally identified levels and extending existing calculations to higher energy levels. For lower levels, R-matrix collisional excitation rates from earlier work have been used. Significant emission is predicted by these calculations in the 5f-3d transitions, which will impact analysis of Solar Dynamics Observatory Atmospheric Imaging Assembly observations using the 94 A filter.

  10. The Bianchi IX model in loop quantum cosmology

    International Nuclear Information System (INIS)

    Bojowald, Martin; Date, Ghanashyam; Hossain, Golam Mortuza

    2004-01-01

    The Bianchi IX model has been used often to investigate the structure close to singularities of general relativity. Its classical chaos is expected to have, via the BKL scenario, implications even for the approach to general inhomogeneous singularities. Thus, it is a popular model to test consequences of modifications to general relativity suggested by quantum theories of gravity. This paper presents a detailed proof that modifications coming from loop quantum gravity lead to a non-chaotic effective behaviour. The way this is realized, independently of quantization ambiguities, suggests a new look at initial and final singularities

  11. Effect of IX dosing on polypropylene and PVDF membrane fouling control

    KAUST Repository

    Myat, Darli Theint

    2013-07-01

    The performance of ion exchange (IX) resin for organics removal from wastewater was assessed using advanced characterisation techniques for varying doses of IX. Organic characterisation using liquid chromatography with a photodiode array (PDA) and fluorescence spectroscopy (Method A), and UV254, organic carbon and organic nitrogen detectors (Method B), was undertaken on wastewater before and after magnetic IX treatment. Results showed partial removal of the biopolymer fraction at high IX doses. With increasing concentration of IX, evidence for nitrogen-containing compounds such as proteins and amino acids disappeared from the LC-OND chromatogram, complementary to the fluorescence response. A greater fluorescence response of tryptophan-like proteins (278nm/343nm) for low IX concentrations was consistent with aggregation of tryptophan-like compounds into larger aggregates, either by self-aggregation or with polysaccharides. Recycling of IX resin through multiple adsorption steps without regeneration maintained the high level of humics removal but there was no continued removal of biopolymer. Subsequent membrane filtration of the IX treated waters resulted in complex fouling trends. Filtration tests with either polypropylene (PP) or polyvinylidene fluoride (PVDF) membranes showed higher rates of initial fouling following treatment with high IX doses (10mL/L) compared to filtration of untreated water, while treatment with lower IX doses resulted in decreased fouling rates relative to the untreated water. However, at longer filtration times the rate of fouling of IX treated waters was lower than untreated water and the relative fouling rates corresponded to the amount of biopolymer material in the feed. It was proposed that the mode of fouling changed from pore constriction during the initial filtration period to filter cake build up at longer filtration times. The organic composition strongly influenced the rate of fouling during the initial filtration period due to

  12. A deep x-ray survey of the Pleiades cluster and the B6-A3 main sequence stars in Orion

    Science.gov (United States)

    Caillault, Jean-Pierre

    1993-01-01

    We have obtained deep ROSAT images of three regions within the Pleiades open cluster. We have detected 317 X-ray sources in these ROSAT PSPC images, 171 of which we associate with certain probable members of the Pleiades cluster. We detect nearly all Pleiades members with spectral types later than G0 and within 25 arcminutes of our three field centers where our sensitivity is highest. This has allowed us to derive for the first time the luminosity function for the G, K, and M dwarfs of an open cluster without the need to use statistical techniques to account for the presence of upper limits in the data sample. Because of our high X-ray detection frequency down to the faint limit of the optical catalog, we suspect that some of our unidentified X-ray sources are previously unknown, very low-mass members of the Pleiades. A large fraction of the Pleiades members detected with ROSAT have published rotational velocities. Plots of L(sub x)/L(sub bol) versus spectroscopic rotational velocity show tightly correlated 'saturation' type relations for stars with (B - V)(sub O) greater than 0.60. For each of several color ranges, X-ray luminosities rise rapidly with increasing rotation rate until v sin i approximately equals 15 km/s, and then remain essentially flat for rotation rates up to at least v sin i approximately equal to 100 km/s. The dispersion in rotation among low-mass stars in the Pleiades is by far the dominant contributor to the dispersion in L(subx) at a given mass. Only about 35 percent of the B.A. and early F stars in the Pleiades are detected as X-ray sources in our survey. There is no correlation between X-ray flux and rotation for these stars. The X-ray luminosity function for the early-type Pleiades stars appears to be bimodal, with only a few exceptions. We either detect these stars at fluxes in the range found for low-mass stars or we derive X-ray limits below the level found for most Pleiades dwarfs. The X-ray spectra for the early-type Pleiades stars

  13. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample

    Science.gov (United States)

    Alam, Shadab; Ata, Metin; Bailey, Stephen; Beutler, Florian; Bizyaev, Dmitry; Blazek, Jonathan A.; Bolton, Adam S.; Brownstein, Joel R.; Burden, Angela; Chuang, Chia-Hsun; Comparat, Johan; Cuesta, Antonio J.; Dawson, Kyle S.; Eisenstein, Daniel J.; Escoffier, Stephanie; Gil-Marín, Héctor; Grieb, Jan Niklas; Hand, Nick; Ho, Shirley; Kinemuchi, Karen; Kirkby, David; Kitaura, Francisco; Malanushenko, Elena; Malanushenko, Viktor; Maraston, Claudia; McBride, Cameron K.; Nichol, Robert C.; Olmstead, Matthew D.; Oravetz, Daniel; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Pan, Kaike; Pellejero-Ibanez, Marcos; Percival, Will J.; Petitjean, Patrick; Prada, Francisco; Price-Whelan, Adrian M.; Reid, Beth A.; Rodríguez-Torres, Sergio A.; Roe, Natalie A.; Ross, Ashley J.; Ross, Nicholas P.; Rossi, Graziano; Rubiño-Martín, Jose Alberto; Saito, Shun; Salazar-Albornoz, Salvador; Samushia, Lado; Sánchez, Ariel G.; Satpathy, Siddharth; Schlegel, David J.; Schneider, Donald P.; Scóccola, Claudia G.; Seo, Hee-Jong; Sheldon, Erin S.; Simmons, Audrey; Slosar, Anže; Strauss, Michael A.; Swanson, Molly E. C.; Thomas, Daniel; Tinker, Jeremy L.; Tojeiro, Rita; Magaña, Mariana Vargas; Vazquez, Jose Alberto; Verde, Licia; Wake, David A.; Wang, Yuting; Weinberg, David H.; White, Martin; Wood-Vasey, W. Michael; Yèche, Christophe; Zehavi, Idit; Zhai, Zhongxu; Zhao, Gong-Bo

    2017-09-01

    We present cosmological results from the final galaxy clustering data set of the Baryon Oscillation Spectroscopic Survey, part of the Sloan Digital Sky Survey III. Our combined galaxy sample comprises 1.2 million massive galaxies over an effective area of 9329 deg2 and volume of 18.7 Gpc3, divided into three partially overlapping redshift slices centred at effective redshifts 0.38, 0.51 and 0.61. We measure the angular diameter distance DM and Hubble parameter H from the baryon acoustic oscillation (BAO) method, in combination with a cosmic microwave background prior on the sound horizon scale, after applying reconstruction to reduce non-linear effects on the BAO feature. Using the anisotropic clustering of the pre-reconstruction density field, we measure the product DMH from the Alcock-Paczynski (AP) effect and the growth of structure, quantified by fσ8(z), from redshift-space distortions (RSD). We combine individual measurements presented in seven companion papers into a set of consensus values and likelihoods, obtaining constraints that are tighter and more robust than those from any one method; in particular, the AP measurement from sub-BAO scales sharpens constraints from post-reconstruction BAOs by breaking degeneracy between DM and H. Combined with Planck 2016 cosmic microwave background measurements, our distance scale measurements simultaneously imply curvature ΩK = 0.0003 ± 0.0026 and a dark energy equation-of-state parameter w = -1.01 ± 0.06, in strong affirmation of the spatially flat cold dark matter (CDM) model with a cosmological constant (ΛCDM). Our RSD measurements of fσ8, at 6 per cent precision, are similarly consistent with this model. When combined with supernova Ia data, we find H0 = 67.3 ± 1.0 km s-1 Mpc-1 even for our most general dark energy model, in tension with some direct measurements. Adding extra relativistic species as a degree of freedom loosens the constraint only slightly, to H0 = 67.8 ± 1.2 km s-1 Mpc-1. Assuming flat

  14. HIV prevalence and related risk behaviours in female seasonal farm workers in Souss Massa Draa, Morocco: results from a cross-sectional survey using cluster-based sampling.

    Science.gov (United States)

    Bozicevic, Ivana; Guezzar, Fatiha; Stulhofer, Aleksandar; Bennani, Aziza; Handanagic, Senad; Barbaric, Jelena; El Rhilani, Houssine; Alami, Kamal; Khattabi, Hamida; Riedner, Gabriele; Maaroufi, Abderrahmane

    2017-06-08

    To determine prevalence of HIV and HIV-related behaviours in female seasonal farm workers (FSFWs) in two provinces of Souss Massa Draa (SMD) region in Morocco. SMD has a higher burden of HIV compared with other parts of Morocco and is characterised by a substantial aggregation of FSFW. We carried out a cross-sectional HIV biobehavioural survey using cluster-based sampling of farms in the provinces Chtouka Aït Baha and Taroudant Ouled Teïma in 2014. HIV testing was done using the Determine HIV-1/2 rapid test and reactive specimens were tested using ELISA and western blot. Collected data were post hoc weighted for region-based stratification and adjusted for clustering effects using complex survey functions of SPSS (V.21). Among those eligible to participate, the response rate was 92.8%. HIV prevalence was 0.9% (95% CI 0.4% to 2.4%) among 520 recruited participants. A high proportion of respondents (67.7%) had no education. Ever having sex was reported by 79.8% and among these, 12.7% ever exchanged sex for money or goods. Sixty-one per cent reported condom use at most recent commercial vaginal sex in the past 12 months. STI symptom recognition was found to be low because 62.4% and 46.8% of FSFW could not report any STI symptoms in men and women, respectively. Twenty-seven per cent of respondents had an HIV test in the past 12 months. In multivariable analysis, those with primary or higher education (adjusted OR (aOR)=2.38, 95% CI 1.33 to 4.27) and those who participated in an HIV educational session at their workplace (aOR=11.00, 95% CI 3.99 to 30.31) had higher odds of ever been tested for HIV. Although we found a relatively low HIV prevalence among FSFW in SMD, HIV interventions should be intensified, in particular, in a subgroup of women who are involved in sex work. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  15. GALAXY CLUSTERING AND PROJECTED DENSITY PROFILES AS TRACED BY SATELLITES IN PHOTOMETRIC SURVEYS: METHODOLOGY AND LUMINOSITY DEPENDENCE

    International Nuclear Information System (INIS)

    Wang Wenting; Jing, Y. P.; Li Cheng; Okumura, Teppei; Han Jiaxin

    2011-01-01

    We develop a new method which measures the projected density distribution w p (r p )n of photometric galaxies surrounding a set of spectroscopically identified galaxies and simultaneously the projected cross-correlation function w p (r p ) between the two populations. In this method, we are able to divide the photometric galaxies into subsamples in luminosity intervals even when redshift information is unavailable, enabling us to measure w p (r p )n and w p (r p ) as a function of not only the luminosity of the spectroscopic galaxy, but also that of the photometric galaxy. Extensive tests show that our method can measure w p (r p ) in a statistically unbiased way. The accuracy of the measurement depends on the validity of the assumption inherent to the method that the foreground/background galaxies are randomly distributed and are thus uncorrelated with those galaxies of interest. Therefore, our method can be applied to the cases where foreground/background galaxies are distributed in large volumes, which is usually valid in real observations. We have applied our method to data from the Sloan Digital Sky Survey (SDSS) including a sample of 10 5 luminous red galaxies at z ∼ 0.4 and a sample of about half a million galaxies at z ∼ 0.1, both of which are cross-correlated with a deep photometric sample drawn from the SDSS. On large scales, the relative bias factor of galaxies measured from w p (r p ) at z ∼ 0.4 depends on luminosity in a manner similar to what is found for those at z ∼ 0.1, which are usually probed by autocorrelations of spectroscopic samples in previous studies. On scales smaller than a few Mpc and at both z ∼ 0.4 and z ∼ 0.1, the photometric galaxies of different luminosities exhibit similar density profiles around spectroscopic galaxies at fixed luminosity and redshift. This provides clear observational support for the assumption commonly adopted in halo occupation distribution models that satellite galaxies of different luminosities are

  16. Globular Clusters - Guides to Galaxies

    CERN Document Server

    Richtler, Tom; Joint ESO-FONDAP Workshop on Globular Clusters

    2009-01-01

    The principal question of whether and how globular clusters can contribute to a better understanding of galaxy formation and evolution is perhaps the main driving force behind the overall endeavour of studying globular cluster systems. Naturally, this splits up into many individual problems. The objective of the Joint ESO-FONDAP Workshop on Globular Clusters - Guides to Galaxies was to bring together researchers, both observational and theoretical, to present and discuss the most recent results. Topics covered in these proceedings are: internal dynamics of globular clusters and interaction with host galaxies (tidal tails, evolution of cluster masses), accretion of globular clusters, detailed descriptions of nearby cluster systems, ultracompact dwarfs, formations of massive clusters in mergers and elsewhere, the ACS Virgo survey, galaxy formation and globular clusters, dynamics and kinematics of globular cluster systems and dark matter-related problems. With its wide coverage of the topic, this book constitute...

  17. 5-ALA/PpIX fluorescence detection of gastrointestinal neoplasia

    Science.gov (United States)

    Borisova, Ekaterina G.; Vladimirov, Borislav; Terziev, Ivan; Ivanova, Radina; Avramov, Latchezar

    2009-07-01

    In the recent study delta-ALA/PpIX is used as fluorescent marker for dysplasia and tumor detection in esophagus, stomach and colon. ALA is administered per os six to eight (depending on the lesion location) hours before measurements at dose 20mg/kg weight. High-power light-emitting diode at 405 nm is used as an excitation source. Special opto-mechanical device is built for the LED to use the light guide of standard video-endoscopic system. Through endoscopic instrumental channel a fiber is applied to return information about fluorescence to microspectrometer. The fluorescence detected from tumor sites has very complex spectral origins. It consists of autofluorescence, fluorescence from exogenous fluorophores and re-absorption from the chromophores accumulated in the tissue investigated. Spectral features observed during endoscopic investigations could be distinct as the next regions: 450-630 nm region, where tissue autofluorescence is observed; 630-710 nm region, where fluorescence of PpIX is clearly pronounced; 530-580 nm region, where minima in the autofluorescence signal are observed, related to re-absorption of oxy-hemoglobin in this spectral area. Endogenous and exogenous fluorescence spectra are used to develop simple but effective algorithm, based on dimensionless ratio of the signals at 560 and 635 nm, for differentiation of normal/abnormal gastrointestinal tissues. Very good correlation between fluorescence signals and histology examination of the lesions investigated is achieved.

  18. A Place on the Team: The Triumph and Tragedy of Title IX

    Science.gov (United States)

    Suggs, Welch

    2006-01-01

    "A Place on the Team" is the inside story of how Title IX revolutionized American sports. The federal law guaranteeing women's rights in education, Title IX opened gymnasiums and playing fields to millions of young women previously locked out. Journalist Welch Suggs chronicles both the law's successes and failures-the exciting…

  19. Why, What and Where To? Title IX, Educational Amendment of 1972.

    Science.gov (United States)

    Perry-Miller, Mitzi

    Three years after Title IX of the Education Amendments of 1972 became law, the U. S. Department of Health, Education, and Welfare provided regulations for the implementation of Title IX. This report reviews the implications of these regulations as well as several of the court cases in which discrimination on the basis of sex has been declared…

  20. Not Second-Class: Title IX, Equity, and Girls' High School Sports

    Science.gov (United States)

    Stader, David L.; Surface, Jeanne L.

    2014-01-01

    Title IX is designed to protect students from discrimination based on sex in any educational institution that receives financial assistance. This article focuses on Title IX as it applies to high school athletic programs by considering the trial of a high school district in California. A federal court found considerable inequalities between boys…

  1. The feasibility of using concentrates containing factor IX for continuous infusion.

    Science.gov (United States)

    Schulman, S; Gitel, S; Zivelin, A; Katsarou, O; Mandalaki, T; Varon, D; Martinowitz, U

    1995-04-01

    We have investigated the feasibility of continuous infusion of undiluted factor IX (F IX) over several days using minipumps. The stabilities of seven different reconstituted F IX products were substantially better than those declared by the manufacturers. Several concentrates maintained factor activities 80% of baseline for the entire period of 4 weeks at 4-8d̀C as did one product at 20-23d̀A. At 37d̀C the latter concentrate was stable for at least 1 week. The stability seemed to correlate with the purity of the product. Analysis of two prothrombin comples concentrates by gel electrophoresis demonstrated degradation of prothrombin to prethrombin-1 and fragment 1 at 37d̀C and in one of the concentrates also at 20-23d̀C. In two F IX concentrates the corresponding analysis did not reveal any degradation. Four patients were treated with continuous infusion with a pure F IX concentrate (Mononine™, Armour) after surgery or for serious haemorrhage (two each) with good haemostatic effect, an initial progressive decrease of the F IX clearance, and no side-effects. Continuous infusion with F IX, using a minipump and undiluted reconstituted factor, is therefore feasible and effective, and can be conveniently prepared for several days at a time. Pure F IX products are more stable and probably safer for this purpose.

  2. An update on anticancer drug development and delivery targeting carbonic anhydrase IX

    Directory of Open Access Journals (Sweden)

    Justina Kazokaitė

    2017-11-01

    Full Text Available The expression of carbonic anhydrase (CA IX is up-regulated in many types of solid tumors in humans under hypoxic and acidic microenvironment. Inhibition of CA IX enzymatic activity with selective inhibitors, antibodies or labeled probes has been shown to reverse the acidic environment of solid tumors and reduce the tumor growth establishing the significant role of CA IX in tumorigenesis. Thus, the development of potent antitumor drugs targeting CA IX with minimal toxic effects is important for the target-specific tumor therapy. Recently, several promising antitumor agents against CA IX have been developed to treat certain types of cancers in combination with radiation and chemotherapy. Here we review the inhibition of CA IX by small molecule compounds and monoclonal antibodies. The methods of enzymatic assays, biophysical methods, animal models including zebrafish and Xenopus oocytes, and techniques of diagnostic imaging to detect hypoxic tumors using CA IX-targeted conjugates are discussed with the aim to overview the recent progress related to novel therapeutic agents that target CA IX in hypoxic tumors.

  3. On the role of type IX collagen in the extracellular matrix of cartilage: type IX collagen is localized to intersections of collagen fibrils

    OpenAIRE

    1986-01-01

    The tissue distribution of type II and type IX collagen in 17-d-old chicken embryo was studied by immunofluorescence using polyclonal antibodies against type II collagen and a peptic fragment of type IX collagen (HMW), respectively. Both proteins were found only in cartilage where they were co-distributed. They occurred uniformly throughout the extracellular matrix, i.e., without distinction between pericellular, territorial, and interterritorial matrices. Tissues that undergo endochondral bo...

  4. 4p-5s transitions in YVII, VIII, ZrVIII, IX, NbIX, X and MoX, XI

    International Nuclear Information System (INIS)

    Rahimullah, K.; Chaghtai, M.S.Z.; Khatoon, S.

    1976-01-01

    The spectra of Y VII, VIII, Zr VIII, IX, Nb X and Mo X, XI are studied for the first time and the 1971 analysis of Nb IX is improved. By analyses of the transitions 4s 2 4psup(k)-4s 2 4psup(k-1)5s all the levels of the configurations 4p 3 , 4p 2 5s, 4p 2 and 4p5s are established in the spectra concerned. (Auth.)

  5. Timeliness and completeness of measles vaccination among children in rural areas of Guangxi, China: A stratified three-stage cluster survey.

    Science.gov (United States)

    Tang, Xianyan; Geater, Alan; McNeil, Edward; Zhou, Hongxia; Deng, Qiuyun; Dong, Aihu

    2017-07-01

    Large-scale outbreaks of measles occurred in 2013 and 2014 in rural Guangxi, a region in Southwest China with high coverage for measles-containing vaccine (MCV). This study aimed to estimate the timely vaccination coverage, the timely-and-complete vaccination coverage, and the median delay period for MCV among children aged 18-54 months in rural Guangxi. Based on quartiles of measles incidence during 2011-2013, a stratified three-stage cluster survey was conducted from June through August 2015. Using weighted estimation and finite population correction, vaccination coverage and 95% confidence intervals (CIs) were calculated. Weighted Kaplan-Meier analyses were used to estimate the median delay periods for the first (MCV1) and second (MCV2) doses of the vaccine. A total of 1216 children were surveyed. The timely vaccination coverage rate was 58.4% (95% CI, 54.9%-62.0%) for MCV1, and 76.9% (95% CI, 73.6%-80.0%) for MCV2. The timely-and-complete vaccination coverage rate was 47.4% (95% CI, 44.0%-51.0%). The median delay period was 32 (95% CI, 27-38) days for MCV1, and 159 (95% CI, 118-195) days for MCV2. The timeliness and completeness of measles vaccination was low, and the median delay period was long among children in rural Guangxi. Incorporating the timeliness and completeness into official routine vaccination coverage statistics may help appraise the coverage of vaccination in China. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  6. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmic flows and cosmic web from luminous red galaxies

    Science.gov (United States)

    Ata, Metin; Kitaura, Francisco-Shu; Chuang, Chia-Hsun; Rodríguez-Torres, Sergio; Angulo, Raul E.; Ferraro, Simone; Gil-Marín, Hector; McDonald, Patrick; Hernández Monteagudo, Carlos; Müller, Volker; Yepes, Gustavo; Autefage, Mathieu; Baumgarten, Falk; Beutler, Florian; Brownstein, Joel R.; Burden, Angela; Eisenstein, Daniel J.; Guo, Hong; Ho, Shirley; McBride, Cameron; Neyrinck, Mark; Olmstead, Matthew D.; Padmanabhan, Nikhil; Percival, Will J.; Prada, Francisco; Rossi, Graziano; Sánchez, Ariel G.; Schlegel, David; Schneider, Donald P.; Seo, Hee-Jong; Streblyanska, Alina; Tinker, Jeremy; Tojeiro, Rita; Vargas-Magana, Mariana

    2017-06-01

    We present a Bayesian phase-space reconstruction of the cosmic large-scale matter density and velocity fields from the Sloan Digital Sky Survey-III Baryon Oscillations Spectroscopic Survey Data Release 12 CMASS galaxy clustering catalogue. We rely on a given Λ cold dark matter cosmology, a mesh resolution in the range of 6-10 h-1 Mpc, and a lognormal-Poisson model with a redshift-dependent non-linear bias. The bias parameters are derived from the data and a general renormalized perturbation theory approach. We use combined Gibbs and Hamiltonian sampling, implemented in the argo code, to iteratively reconstruct the dark matter density field and the coherent peculiar velocities of individual galaxies, correcting hereby for coherent redshift space distortions. Our tests relying on accurate N-body-based mock galaxy catalogues show unbiased real space power spectra of the non-linear density field up to k ˜ 0.2 h Mpc-1, and vanishing quadrupoles down to r ˜ 20 h-1 Mpc. We also demonstrate that the non-linear cosmic web can be obtained from the tidal field tensor based on the Gaussian component of the reconstructed density field. We find that the reconstructed velocities have a statistical correlation coefficient compared to the true velocities of each individual light-cone mock galaxy of r ˜ 0.68 including about 10 per cent of satellite galaxies with virial motions (about r = 0.75 without satellites). The power spectra of the velocity divergence agree well with theoretical predictions up to k ˜ 0.2 h Mpc-1. This work will be especially useful to improve, for example, baryon acoustic oscillation reconstructions, kinematic Sunyaev-Zeldovich, integrated Sachs-Wolfe measurements or environmental studies.

  7. Timeliness and completeness of measles vaccination among children in rural areas of Guangxi, China: A stratified three-stage cluster survey

    Directory of Open Access Journals (Sweden)

    Xianyan Tang

    2017-07-01

    Full Text Available Background: Large-scale outbreaks of measles occurred in 2013 and 2014 in rural Guangxi, a region in Southwest China with high coverage for measles-containing vaccine (MCV. This study aimed to estimate the timely vaccination coverage, the timely-and-complete vaccination coverage, and the median delay period for MCV among children aged 18–54 months in rural Guangxi. Methods: Based on quartiles of measles incidence during 2011–2013, a stratified three-stage cluster survey was conducted from June through August 2015. Using weighted estimation and finite population correction, vaccination coverage and 95% confidence intervals (CIs were calculated. Weighted Kaplan–Meier analyses were used to estimate the median delay periods for the first (MCV1 and second (MCV2 doses of the vaccine. Results: A total of 1216 children were surveyed. The timely vaccination coverage rate was 58.4% (95% CI, 54.9%–62.0% for MCV1, and 76.9% (95% CI, 73.6%–80.0% for MCV2. The timely-and-complete vaccination coverage rate was 47.4% (95% CI, 44.0%–51.0%. The median delay period was 32 (95% CI, 27–38 days for MCV1, and 159 (95% CI, 118–195 days for MCV2. Conclusions: The timeliness and completeness of measles vaccination was low, and the median delay period was long among children in rural Guangxi. Incorporating the timeliness and completeness into official routine vaccination coverage statistics may help appraise the coverage of vaccination in China.

  8. Cluster headache

    Science.gov (United States)

    Histamine headache; Headache - histamine; Migrainous neuralgia; Headache - cluster; Horton's headache; Vascular headache - cluster ... Doctors do not know exactly what causes cluster headaches. They ... (chemical in the body released during an allergic response) or ...

  9. Functional consequences of an arginine180 to glutamine mutation in factor IX Hilo.

    Science.gov (United States)

    Monroe, D M; McCord, D M; Huang, M N; High, K A; Lundblad, R L; Kasper, C K; Roberts, H R

    1989-05-01

    Factor IX Hilo is a variant factor IX molecule that has no detectable coagulant activity. The defect in factor IX Hilo arises from a point mutation in the gene such that in the protein Arg180 is converted to a Gln. Activation of factor IX Hilo by factor Xla was monitored using the fluorescent active site probe p-aminobenzamidine. Normal factor IX showed complete activation in one hour as determined by measuring the increase in fluorescence when p-aminobenzamidine bound to activated factor IX. Factor IX Hilo showed no increase in fluorescence even after 24 hours, indicating that the active site was not exposed. Polyacrylamide gel electrophoresis showed that factor IX Hilo was cleaved to a light chain plus a larger peptide with a molecular weight equivalent to a heavy chain covalently linked to an activation peptide. Amino terminal amino acid sequencing of factor IX Hilo cleaved by factor Xla showed cleavage only at Arg145-Ala146, indicating that the Gln180-Val181 bond was not cleaved and that the active site was thus not exposed. The presence of factor IX Hilo in patient plasma was responsible for the patient having a very long ox brain prothrombin time characteristic of severe hemophilia Bm. Patient plasma had an ox brain prothrombin time of 100 seconds using a Thrombotest kit, significantly prolonged over the normal control value of 45 seconds. When factor IX Hilo was depleted from patient plasma using an immunoaffinity column, the ox brain prothrombin time decreased to 41 seconds. When factor IX Hilo was added back to depleted patient plasma, to normal plasma depleted of factor IX by the same affinity column, or to plasma from a CRM- hemophilia B patient, the ox brain prothrombin time was significantly prolonged. We conclude that the Arg180 to Gln mutation in factor IX Hilo results in a molecule that cannot be activated by factor Xla. Further, our data suggest that the mutation results in a molecule that interacts with components of the extrinsic pathway to give

  10. Molecular and electronic structure of thin films of protoporphyrin(IX)Fe(III)Cl

    Science.gov (United States)

    Snyder, Shelly R.; White, Henry S.

    1991-11-01

    Electrochemical, scanning tunneling microscopy (STM), and tunneling spectroscopy studies of the molecular and electronic properties of thin films of protoporphyrin(IX)Fe(III)Cl (abbreviated as PP(IX)Fe(III)Cl) on highly oriented pyrolytic graphite (HOPG) electrodes are reported. PP(IX)Fe(III)Cl films are prepared by two different methods: (1) adsorption, yielding an electrochemically-active film, and (2) irreversible electrooxidative polymerization, yielding an electrochemically-inactive film. STM images, in conjunction with electro-chemical results, indicate that adsorption of PP(IX)Fe(III)Cl from aqueous solutions onto freshly cleaved HOPG results in a film comprised of molecular aggregates. In contrast, films prepared by irreversible electrooxidative polymerization of PP(IX)Fe(III)Cl have a denser, highly structured morphology, including what appear to be small pinholes (approx. 50A diameter) in an otherwise continuous film.

  11. Lansoprazole and carbonic anhydrase IX inhibitors sinergize against human melanoma cells.

    Science.gov (United States)

    Federici, Cristina; Lugini, Luana; Marino, Maria Lucia; Carta, Fabrizio; Iessi, Elisabetta; Azzarito, Tommaso; Supuran, Claudiu T; Fais, Stefano

    2016-01-01

    Proton Pump Inhibitors (PPIs) reduce tumor acidity and therefore resistance of tumors to drugs. Carbonic Anhydrase IX (CA IX) inhibitors have proven to be effective against tumors, while tumor acidity might impair their full effectiveness. To analyze the effect of PPI/CA IX inhibitors combined treatment against human melanoma cells. The combination of Lansoprazole (LAN) and CA IX inhibitors (FC9-399A and S4) has been investigated in terms of cell proliferation inhibition and cell death in human melanoma cells. The combination of these inhibitors was more effective than the single treatments in both inhibiting cell proliferation and in inducing cell death in human melanoma cells. These results represent the first successful attempt in combining two different proton exchanger inhibitors. This is the first evidence on the effectiveness of a new approach against tumors based on the combination of PPI and CA IX inhibitors, thus providing an alternative strategy against tumors.

  12. The importance of protoporphyrin IX efflux for ALA-PDT dosimetry

    International Nuclear Information System (INIS)

    Milanetto, M C; Imasato, H; Perussi, J R

    2009-01-01

    One of the major advances in PDT is the use of 5-aminolevulinic acid (ALA) to induce the production of an endogenous photosensitizer inside the cells using intracellular enzymatic pathways. ALA is the first intermediate in heme biosynthesis and a precursor of the protoporphyrin IX (PpIX). When activated by light, this efficient photosensitizer accumulated in the target cells can produce cytotoxicity. The aim of this study was to find the best conditions for cell killing using ALA to temporarily increase the concentration of PpIX in two cell lines. It was shown that a considerable efflux of synthesized PpIX occurs. Since this efflux is time-dependent, it is essential to know the optimum time for irradiation after ALA administration. So, the efflux of PpIX from the cells is an important parameter to be considered for ALA-PDT dosimetry

  13. Changes and socioeconomic factors associated with attitudes towards domestic violence among Vietnamese women aged 15-49: findings from the Multiple Indicator Cluster Surveys, 2006-2011.

    Science.gov (United States)

    Trinh, Oanh Thi Hoang; Oh, Juhwan; Choi, Sugy; To, Kien Gia; Van Do, Dung

    2016-01-01

    Understanding factors associated with domestic violence-supportive attitudes among Vietnamese women is important for designing effective policies to prevent this behavior. Previous studies have largely overlooked risk factors associated with domestic violence-supportive attitudes by women in Vietnam. This paper explores and identifies socioeconomic factors that contribute to domestic violence-supportive attitudes among Vietnamese women using data from the Multiple Indicator Cluster Surveys (MICS). Secondary data from two cross-sectional studies (MICS 3, 2006, and MICS 4, 2011) with representative samples (9,471 and 11,663 women, respectively) in Vietnam were analyzed. The prevalence of supportive attitudes toward domestic violence and associations with age, residence region, area, education level, household wealth index, ethnicity, and marital status were estimated using descriptive statistics and multivariate Poisson models, giving estimates of relative risk. Overall, the prevalence of acceptance of domestic violence declined between 2006 and 2011 in Vietnam (65.1% vs. 36.1%). Socioeconomic factors associated with women's condoning of domestic violence were age, wealth, education level, and living area. In particular, younger age and low educational attainment were key factors associated with violence-supportive attitudes, and these associations have become stronger over time. Higher educational attainment in women is an important predictor of women's attitudes toward domestic violence. To date, Doi Moi and the Vietnamese government's commitment to the Millennium Development Goals may have positively contributed to lowering the acceptance of domestic violence. Tailored interventions that focus on education will be important in further changing attitudes toward domestic violence.

  14. Long-term survey of lion-roar emissions inside the terrestrial magnetosheath obtained from the STAFF-SA measurements onboard the Cluster spacecraft

    Science.gov (United States)

    Pisa, D.; Krupar, V.; Kruparova, O.; Santolik, O.

    2017-12-01

    Intense whistler-mode emissions known as 'lion-roars' are often observed inside the terrestrial magnetosheath, where the solar wind plasma flow slows down, and the local magnetic field increases ahead of a planetary magnetosphere. Plasma conditions in this transient region lead to the electron temperature anisotropy, which can result in the whistler-mode waves. The lion-roars are narrow-band emissions with typical frequencies between 0.1-0.5 Fce, where Fce is the electron cyclotron frequency. We present results of a long-term survey obtained by the Spatio Temporal Analysis Field Fluctuations - Spectral Analyzer (STAFF-SA) instruments on board the four Cluster spacecraft between 2001 and 2010. We have visually identified the time-frequency intervals with the intense lion-roar signature. Using the Singular Value Decomposition (SVD) method, we analyzed the wave propagation properties. We show the spatial, frequency and wave power distributions. Finally, the wave properties as a function of upstream solar wind conditions are discussed.

  15. 19.-25. IX toimub Rüütelkonna hoones Kumu pärlite nädal...

    Index Scriptorium Estoniae

    2005-01-01

    23. IX kõneleb Anu Allikvee teemal "Eestlane baltisaksa kunstnike vaatepiiris"; 24. IX tutvustab Mai Levin Eugen Dückeri maale, 25. IX Ene Lamp Konrad Mäge. Vt. ka lk. 24 Tähtede nädal 26. IX-2. X - kohtumisõhtutel esinevad Marika ja Heinz Valk, Jüri Kuuskemaa, Sirje Helme, Pekka Vapaavuori, Inge Teder, Rain Lõhmus

  16. Inactivation of Dengue and Yellow Fever viruses by heme, cobalt-protoporphyrin IX and tin-protoporphyrin IX.

    Science.gov (United States)

    Assunção-Miranda, I; Cruz-Oliveira, C; Neris, R L S; Figueiredo, C M; Pereira, L P S; Rodrigues, D; Araujo, D F F; Da Poian, A T; Bozza, M T

    2016-03-01

    To investigate the effect of heme, cobalt-protoporphyrin IX and tin-protoporphyrin IX (CoPPIX and SnPPIX), macrocyclic structures composed by a tetrapyrrole ring with a central metallic ion, on Dengue Virus (DENV) and Yellow Fever Virus (YFV) infection. Treatment of HepG2 cells with heme, CoPPIX and SnPPIX after DENV infection reduced infectious particles without affecting viral RNA contents in infected cells. The reduction of viral load occurs only with the direct contact of DENV with porphyrins, suggesting a direct effect on viral particles. Previously incubation of DENV and YFV with heme, CoPPIX and SnPPIX resulted in viral particles inactivation in a dose-dependent manner. Biliverdin, a noncyclical porphyrin, was unable to inactivate the viruses tested. Infection of HepG2 cells with porphyrin-pretreated DENV2 results in a reduced or abolished viral protein synthesis, RNA replication and cell death. Treatment of HepG2 or THP-1 cell lineage with heme or CoPPIX after DENV infection with a very low MOI resulted in a decreased DENV replication and protection from death. Heme, CoPPIX and SnPPIX possess a marked ability to inactivate DENV and YFV, impairing its ability to infect and induce cytopathic effects on target cells. These results open the possibility of therapeutic application of porphyrins or their use as models to design new antiviral drugs against DENV and YFV. © 2016 The Society for Applied Microbiology.

  17. In vitro characterization of high purity factor IX concentrates for the treatment of hemophilia B.

    Science.gov (United States)

    Limentani, S A; Gowell, K P; Deitcher, S R

    1995-04-01

    This study employed sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis and immunoblotting to assess the purity of seven high purity factor IX concentrates: Aimafix (Aima), AlphaNine-SD (Alpha Therapeutic), Factor IX VHP (Biotransfusion), Immunine (Immuno), Mononine (Armour Pharmaceutical), Nanotiv (Kabi Pharmacia), and 9MC (Blood Products Laboratory). The mean specific activity of these products ranged from 68 U factor IX/mg (Aimafix) to 246 U factor IX/mg (Mononine). SDS-PAGE analysis showed that the highest purity product, Mononine, had a single contaminating band under non-reducing conditions. Two additional bands were detected when this product was analyzed under reducing conditions. All other products had multiple contaminating bands that were more apparent under reducing than non-reducing conditions. The immunoblot for factor IX showed a dominant factor IX band for all products. In addition, visible light chain of factor IX was detected for AlphaNine-SD, Factor IX VHP, Immunine, Mononine, Nanotiv, and 9MC, suggesting that the factor IX in these products had undergone partial activation to factor IXa. Another contaminating band was visible at 49,500 for all of the products except 9MC. In addition to this band, high molecular weight contaminants were apparent for some products, most notably AlphaNine-SD. The identity of these bands is unknown. Immunoblotting failed to demonstrate factor VII as a contaminant of any of the high purity products, although factor VIIa could be detected in some lots of Immunine, Nanotiv, and 9MC by a clot-based assay. Factor X contaminated Aimafix, AlphaNine-SD, Factor IX VHP, Immunine, Nanotiv, and 9MC, but activation products of factor X were not detected.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Increase in protoporphyrin IX after 5-aminolevulinic acid based photodynamic therapy is due to local re-synthesis

    NARCIS (Netherlands)

    de Bruijn, Henriëtte S.; Kruijt, Bastiaan; van der Ploeg-van den Heuvel, Angélique; Sterenborg, Henricus J. C. M.; Robinson, Dominic J.

    2007-01-01

    Protoporphyrin IX (PpIX) fluorescence that is bleached during aminolevulinic acid (ALA) mediated photodynamic therapy (PDT) increases again in time after treatment. In the present study we investigated if this increase in PpIX fluorescence after illumination is the result of local re-synthesis or of

  19. Induction of protoporphyrin IX by aminolaevulinic acid in actinic keratosis, psoriasis and normal skin: preferential porphyrin enrichment in differentiated cells.

    NARCIS (Netherlands)

    Smits, T.; Laarhoven, A.I.M. van; Staassen, A.; Kerkhof, P.C.M. van de; Erp, P.E.J. van; Gerritsen, M.J.P.

    2009-01-01

    BACKGROUND: In photodynamic therapy the endogenous photosensitizer protoporphyrin IX (PpIX) is synthesized following topical application of aminolaevulinic acid (ALA). However, different tissues have distinct PpIX-accumulating properties, due to differences in penetration of ALA through the stratum

  20. Validation of the protoporphyrin IX-triplet state lifetime technique for mitochondrial oxygen measurements in the skin

    NARCIS (Netherlands)

    F.A. Harms (Floor A.); S.I.A. Bodmer (Sander I. A.); N.J.H. Raat (Nicolaas); R.J. Stolker (Robert); E.G. Mik (Egbert)

    2012-01-01

    textabstractMitochondrial oxygen tension can be measured in vivo by means of oxygen-dependent quenching of delayed fluorescence of protoporphyrin IX (PpIX). Here we demonstrate that mitochondrial PO2 (mitoPO2) can be measured in the skin of a rat after topical application of the PpIX precursor

  1. Radio investigations of clusters of galaxies

    International Nuclear Information System (INIS)

    Valentijn, E.A.

    1978-01-01

    This thesis contains a number of papers of the series entitled, A Westerbork Survey of Rich Clusters of Galaxies. The primary aim was to study the radio characteristics of cluster galaxies and especially the question whether their ''radio-activity'' is influenced by their location inside a cluster. It is enquired whether the presence of an intra-cluster medium (ICM), or the typical cluster evolution or cluster dynamical processes can give rise to radio-observable effects on the behaviour of cluster galaxies. 610 MHz WSRT observations of the Coma cluster (and radio observations of the Hercules supercluster) are presented. Extended radio sources in Abell clusters are then described. (Auth.)

  2. Labelling IDS clusters by means of the silhouette index

    OpenAIRE

    Petrovic, Slovodan; Álvarez, Gonzalo; Orfila, Agustín; Carbó, Javier

    2006-01-01

    Proceeding of: IX Reunión Española sobre Criptología y Seguridad de la Información. Barcelona, 2006 One of the most difficult problems in the design of an anomaly based intrusion detection system (IDS) that uses clustering is that of labelling the ob- tained clusters, i.e. determining which of them correspond to ”good” behaviour on the network/host and which to ”bad” behaviour. In this paper, a new clusters’ labelling strategy, which makes use of the Silhouette clustering quality index is ...

  3. THE IX EUROPEAN FORUM ON ANTIPHOSPHOLIPID ANTIBODIES. A BRIEF REVIEW

    Directory of Open Access Journals (Sweden)

    Nataliya V Seredavkina

    2014-01-01

    Full Text Available The article presents a brief review of the proceedings of the IX European Forum on antiphospholipid antibodies held in May 2013 in Krakow (Poland. The aim of the Forum is to coordinate multicenter projects focused on antiphospholipid antibodies (aPL, both clinical and fundamental research, based on cooperation between the European countries. The main purpose is to stimulate research into all aspects of aPL, to facilitate the exchange of information between institutions, and to involve many centers in different countries into scientific research on this issue. The issues of standardization of the diagnostic criteria for antiphospholipid syndrome (APS, primarily serological markers (their specificity, sensitivity and correlation with clinical manifestations, as well as non-criterial manifestations of APS, were considered at the meeting. In addition, the therapy problems were discussed.

  4. The order of chaos on a Bianch IX cosmological model

    Energy Technology Data Exchange (ETDEWEB)

    Bugalho, H; da Silva, A R; Ramos, J S

    1986-12-01

    The purpose of this paper is to analyze the chaotic behavior that can arise on a type-IX cosmological model using methods from dynamic systems theory and symbolic dynamics. Specifically, instead of the Belinski-Khalatnikov-Lifschitz model, we use the iterates of a monotonously increasing map of the circle with a discontinuity, and for the Hamiltonian dynamics of Misner's Mixmaster model we introduce the iterates of a noninvertible map. An equivalence between these two models can easily be brought upon by translating them in symbolic dynamical terms. The resulting symbolic orbits can be inserted in an ordered tree structure set, and so we can present an effective counting and referentation of all period orbits.

  5. Weighted Clustering

    DEFF Research Database (Denmark)

    Ackerman, Margareta; Ben-David, Shai; Branzei, Simina

    2012-01-01

    We investigate a natural generalization of the classical clustering problem, considering clustering tasks in which different instances may have different weights.We conduct the first extensive theoretical analysis on the influence of weighted data on standard clustering algorithms in both...... the partitional and hierarchical settings, characterizing the conditions under which algorithms react to weights. Extending a recent framework for clustering algorithm selection, we propose intuitive properties that would allow users to choose between clustering algorithms in the weighted setting and classify...

  6. Syntheses of carbon-13 labeled protoporphyrin-IX for spectroscopic studies of heme proteins

    International Nuclear Information System (INIS)

    Fujinari, E.M.

    1985-01-01

    The development of various methodologies for synthesis of selectively tailored protoporphyrin-IX dimethyl ester are presented. The iron(II) complex of protoporphyrin-IX is the heme, the prosthetic group for Hb, Mb, cytochromes and peroxidases. The significance of this research is to provide direct means to establish definitive carbon-13 NMR assignments of heme proteins in order to study not only the structure-function relationships, but also protein dynamics of these vital systems. Carbon-13 labeling at the beta-vinyl position was first achieved by ozonolysis of protoporphyrin-IX dimethyl ester. Column LC method were used to first isolate 2,4-diformyldeuteroporphyrin-IX dimethyl ester. Concomitantly, monofomyl-monovinyl porphyrins were obtained as a mixture of two isomers. This mixture was separated by MPLC or prep HPLC to afford the isomerically pure products, Spirographis porphyrin dimethyl ester and Iso-Spirographis porphyrin dimethyl ester. A Wittig reaction to each of these porphyrins with 13 C-methyltriphenylphosphonium iodide gave 2,4-bis[ 13 C 2 ]-vinyl protoporphyrin-IX dimethyl ester, 2-[ 13 C 2 ]-vinyl protoporphyrin-IX dimethyl ester, and the 4-[ 13 C 2 ]-vinyl protoporphyrin-IX dimethyl ester, respectively

  7. Evaluation of Sonochemiluminescence in a Phantom in the Presence of Protoporphyrin IX Conjugated to Nanoparticles

    International Nuclear Information System (INIS)

    Shanei, A.; Sazgarnia, A.; Hassanzadeh-Kayyat, M.; Eshghi, H.; Soudmand, S.; Attaran Kakhki, N.

    2012-01-01

    When a liquid is irradiated with high-intensity and low-frequency ultrasound, acoustic cavitation occurs and there are some methods to determine and quantify this phenomenon. The existing methods for performing these experiments include sonochemiluminescence and chemical dosimetric methods. The particles in a liquid decrease the ultrasonic intensity threshold needed for cavitation onset. In this study, a new nano conjugate made up of Protoporphyrin IX and gold nanoparticles, i.e., Au-PpIX was used to provide nucleation sites for cavitation. The nonradiative relaxation time of PpIX in the presence of GNPs is longer than the similar time for PpIX without GNPs. This effect can be used in medical diagnostic and therapeutic applications. The acoustic cavitation activity was investigated studying integrated sonochemiluminescence signal in the wavelength range of 400-500 nm in polyacrylamide gel phantom containing luminol using a cooled CCD spectrometer at different intensities of 1 MHz ultrasound. In order to confirm these results, a chemical dosimetric method was utilized, too. sonochemiluminescence signal level in gel phantom containing Au-PpIX was higher than the other phantoms. These results have been confirmed by the chemical dosimetric data. This finding can be related to the existence of PpIX as a sensitizer and GNPs as cavitation nuclei. In other words, nanoparticles have acted as the sites for cavitation and have increased the cavitation rate. Another theory is that activation of PpIX has produced more free radicals and has enhanced the sonochemiluminescence signal level.

  8. Speaker segmentation and clustering

    OpenAIRE

    Kotti, M; Moschou, V; Kotropoulos, C

    2008-01-01

    07.08.13 KB. Ok to add the accepted version to Spiral, Elsevier says ok whlile mandate not enforced. This survey focuses on two challenging speech processing topics, namely: speaker segmentation and speaker clustering. Speaker segmentation aims at finding speaker change points in an audio stream, whereas speaker clustering aims at grouping speech segments based on speaker characteristics. Model-based, metric-based, and hybrid speaker segmentation algorithms are reviewed. Concerning speaker...

  9. DNA Damage and Cell Cycle Arrest Induced by Protoporphyrin IX in Sarcoma 180 Cells

    Directory of Open Access Journals (Sweden)

    Qing Li

    2013-09-01

    Full Text Available Background: Porphyrin derivatives have been widely used in photodynamic therapy as effective sensitizers. Protoporphyrin IX (PpIX, a well-known hematoporphyrin derivative component, shows great potential to enhance light induced tumor cell damage. However, PpIX alone could also exert anti-tumor effects. The mechanisms underlying those direct effects are incompletely understood. This study thus investigated the putative mechanisms underlying the anti-tumor effects of PpIX on sarcoma 180 (S180 cells. Methods: S180 cells were treated with different concentrations of PpIX. Following the treatment, cell viability was evaluated by the 3-(4, 5- dimethylthiazol-2-yl-2, 5-diphenyltetrazoliumbromide (MTT assay; Disruption of mitochondrial membrane potential was measured by flow cytometry; The trans-location of apoptosis inducer factor (AIF from mitochondria to nucleus was visualized by confocal laser scanning microscopy; DNA damage was detected by single cell gel electrophoresis; Cell cycle distribution was analyzed by DNA content with flow cytometry; Cell cycle associated proteins were detected by western blotting. Results: PpIX (≥ 1 µg/ml significantly inhibited proliferation and reduced viability of S180 cells in a dose-dependent manner. PpIX rapidly and significantly triggered mitochondrial membrane depolarization, AIF (apoptosis inducer factor translocation from mitochondria to nucleus and DNA damage, effects partially relieved by the specific inhibitor of MPTP (mitochondrial permeability transition pore. Furthermore, S phase arrest and upregulation of the related proteins of P53 and P21 were observed following 12 and 24 h PpIX exposure. Conclusion: PpIX could inhibit tumor cell proliferation by induction of DNA damage and cell cycle arrest in the S phase.

  10. Kinetics of the Factor XIa catalyzed activation of human blood coagulation Factor IX

    International Nuclear Information System (INIS)

    Walsh, P.N.; Bradford, H.; Sinha, D.; Piperno, J.R.; Tuszynski, G.P.

    1984-01-01

    The kinetics of activation of human Factor IX by human Factor XIa was studied by measuring the release of a trichloroacetic acid-soluble tritium-labeled activation peptide from Factor IX. Initial rates of trichloroacetic acid-soluble 3 H-release were linear over 10-30 min of incubation of Factor IX (88 nM) with CaCl 2 (5 mM) and with pure (greater than 98%) Factor XIa (0.06-1.3 nM), which was prepared by incubating human Factor XI with bovine Factor XIIa. Release of 3 H preceded the appearance of Factor IXa activity, and the percentage of 3 H released remained constant when the mole fraction of 3 H-labeled and unlabeled Factor IX was varied and the total Factor IX concentration remained constant. A linear correlation (r greater than 0.98, P less than 0.001) was observed between initial rates of 3 H-release and the concentration of Factor XIa, measured by chromogenic assay and by radioimmunoassay and added at a Factor IX:Factor XIa molar ratio of 70-5,600. Kinetic parameters, determined by Lineweaver-Burk analysis, include K/sub m/ (0.49 microM) of about five- to sixfold higher than the plasma Factor IX concentration, which could therefore regulate the reaction. The catalytic constant (k/sub cat/) (7.7/s) is approximately 20-50 times higher than that reported by Zur and Nemerson for Factor IX activation by Factor VIIa plus tissue factor. Therefore, depending on the relative amounts of Factor XIa and Factor VIIa generated in vivo and other factors which may influence reaction rates, these kinetic parameters provide part of the information required for assessing the relative contributions of the intrinsic and extrinsic pathways to Factor IX activation, and suggest that the Factor XIa catalyzed reaction is physiologically significant

  11. Prevention and Reversal of Antibody Responses Against Factor IX in Gene Therapy for Hemophilia B

    Directory of Open Access Journals (Sweden)

    Sushrusha eNayak

    2011-12-01

    Full Text Available Intramuscular (IM administration of an adeno-associated viral (AAV vector represents a simple and safe method of gene transfer for treatment of the X-linked bleeding disorder hemophilia B (factor IX, F.IX, deficiency. However, the approach is hampered by an increased risk of immune responses against F.IX. Previously, we demonstrated that the drug cocktail of immune suppressants rapamycin, IL-10, and a specific peptide (encoding a dominant CD4+ T cell epitope caused an induction of regulatory T cells (Treg with a concomitant apoptosis of antigen-specific effector T cells (J. Thromb. Haemost. 7:1523, 2009. This protocol was effective in preventing inhibitory antibody formation against human F.IX (hF.IX in muscle gene transfer to C3H/HeJ hemophilia B mice (with targeted F9 gene deletion. Here, we show that this protocol can also be used to reverse inhibitor formation. IM injection of AAV1-hF.IX vector resulted in inhibitors of on average 8-10 BU within 1 month. Subsequent treatment with the tolerogenic cocktail accomplished a rapid reduction of hF.IX-specific antibodies to <2 BU, which lasted for >4.5 months. Systemic hF.IX expression increased from undetectable to >200 ng/ml, and coagulation times improved. In addition, we developed an alternative prophylactic protocol against inhibitor formation that did not require knowledge of T cell epitopes, consisting of daily oral administration of rapamycin for 1-month combined with frequent, low-dose intravenous injection of hF.IX protein. Experiments in T cell receptor transgenic mice showed that the route and dosing schedule of drug administration substantially affected Treg induction. When combined with intravenous antigen administration, oral delivery of rapamycin had to be performed daily in order to induce Treg, which were suppressive and phenotypically comparable to natural Treg.

  12. Modulation of the endogenous production of protoporphyrin IX in a yeast-based model organism

    Science.gov (United States)

    Joniová, Jaroslava; Gerelli, Emmanuel; Wagnières, Georges

    2017-02-01

    The main aim of this study was to assess conditions at which simple yeast-based model organism produces maximal levels of protoporphyrin IX (PpIX) after an exogenous administration of its precursor, 5-aminolevulinic acid (ALA), and the ferrous-ion chelator 2,2'-bipyridyl. We observed that the fluorescing porphyrin, produced after these administrations, was likely to be PpIX since fluorescence spectroscopy of the porphyrins produced endogenously in yeast cells resembles that of PpIX in DMSO and in vivo in the chick's chorioallantoic membrane model. Also, fluorescence lifetimes of these porphyrins are very similar to that of PpIX in vitro and in vivo. This suggests that PpIX is the main fluorescent compound produced by yeast in our conditions. We found that the conditions at which yeast produces the maximal PpIX were a synchronous administration of 5 μM ALA and 1 mM 2,2'-bipyridyl for yeast incubated in aqueous glucose and 1 mM 2,2'-bipyridyl in the presence of YPD medium. Such a simple model is of high interest to study basic mechanisms involved in the mitochondrial respiration since PpIX, which is produced in this organelle, can be used as an oxygen sensor, or to perform photodynamic therapy and photodiagnosis. Since the absorption and scattering coefficients of this model are much smaller than those of soft tissues over the visible part of the spectrum, a version of this model loaded with appropriated amounts of light absorbing and scattering particles could be designed as a phantom to mimic tumors containing PpIX, a useful tool to optimize certain cancer photodetection set-ups.

  13. The Spectroscopy and H-band Imaging of Virgo Cluster Galaxies (SHIVir) Survey: Scaling Relations and the Stellar-to-total Mass Relation

    Energy Technology Data Exchange (ETDEWEB)

    Ouellette, Nathalie N.-Q.; Courteau, Stéphane [Department of Physics, Engineering Physics and Astronomy, Queen’s University, Kingston, ON K7L 3N6 (Canada); Holtzman, Jon A. [Department of Physics and Astronomy, New Mexico State University, Las Cruces, NM, 88003-8001 (United States); Dutton, Aaron A. [Department of Physics, New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Cappellari, Michele [Sub-department of Astrophysics, Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Dalcanton, Julianne J. [Department of Astronomy, University of Washington, Seattle, WA, 98195 (United States); McDonald, Michael [MIT Kavli Institute for Astrophysics and Space Research, MIT, Cambridge, MA, 02139 (United States); Roediger, Joel C.; Côté, Patrick; Ferrarese, Laura [Herzberg Institute of Astrophysics, National Research Council, Victoria, BC, V9E 2E7 (Canada); Taylor, James E. [Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, N2L 3G1 (Canada); Tully, R. Brent [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822-1839 (United States); Peng, Eric W. [Department of Astronomy, Peking University, Beijing 100871 (China)

    2017-07-01

    We present parameter distributions and fundamental scaling relations for 190 Virgo cluster galaxies in the SHIVir survey. The distribution of galaxy velocities is bimodal about V {sub circ} ∼ 125 km s{sup −1}, hinting at the existence of dynamically unstable modes in the inner regions of galaxies. An analysis of the Tully-Fisher relation (TFR) of late-type galaxies (LTGs) and the fundamental plane (FP) of early-type galaxies (ETGs) is presented, yielding a compendium of galaxy scaling relations. The slope and zero-point of the Virgo TFR match those of field galaxies, while scatter differences likely reflect distinct evolutionary histories. The velocities minimizing scatter for the TFR and FP are measured at large apertures where the baryonic fraction becomes subdominant. While TFR residuals remain independent of any galaxy parameters, FP residuals (i.e., the FP “tilt”) correlate strongly with the dynamical-to-stellar mass ratio, yielding stringent galaxy formation constraints. We construct a stellar-to-total mass relation (STMR) for ETGs and LTGs and find linear but distinct trends over the range M {sub *} = 10{sup 8–11} M {sub ⊙}. Stellar-to-halo mass relations (SHMRs), which probe the extended dark matter halo, can be scaled down to masses estimated within the optical radius, showing a tight match with the Virgo STMR at low masses; possibly inadequate halo abundance matching prescriptions and broad radial scalings complicate this comparison at all masses. While ETGs appear to be more compact than LTGs of the same stellar mass in projected space, their mass-size relations in physical space are identical. The trends reported here may soon be validated through well-resolved numerical simulations.

  14. Changes and socioeconomic factors associated with attitudes towards domestic violence among Vietnamese women aged 15–49: findings from the Multiple Indicator Cluster Surveys, 2006–2011

    Directory of Open Access Journals (Sweden)

    Oanh Thi Hoang Trinh

    2016-02-01

    Full Text Available Background: Understanding factors associated with domestic violence-supportive attitudes among Vietnamese women is important for designing effective policies to prevent this behavior. Previous studies have largely overlooked risk factors associated with domestic violence-supportive attitudes by women in Vietnam. Objective: This paper explores and identifies socioeconomic factors that contribute to domestic violence–supportive attitudes among Vietnamese women using data from the Multiple Indicator Cluster Surveys (MICS. Design: Secondary data from two cross-sectional studies (MICS 3, 2006, and MICS 4, 2011 with representative samples (9,471 and 11,663 women, respectively in Vietnam were analyzed. The prevalence of supportive attitudes toward domestic violence and associations with age, residence region, area, education level, household wealth index, ethnicity, and marital status were estimated using descriptive statistics and multivariate Poisson models, giving estimates of relative risk. Results: Overall, the prevalence of acceptance of domestic violence declined between 2006 and 2011 in Vietnam (65.1% vs. 36.1%. Socioeconomic factors associated with women's condoning of domestic violence were age, wealth, education level, and living area. In particular, younger age and low educational attainment were key factors associated with violence-supportive attitudes, and these associations have become stronger over time. Conclusion: Higher educational attainment in women is an important predictor of women's attitudes toward domestic violence. To date, Doi Moi and the Vietnamese government's commitment to the Millennium Development Goals may have positively contributed to lowering the acceptance of domestic violence. Tailored interventions that focus on education will be important in further changing attitudes toward domestic violence.

  15. Increased protoporphyrin IX accumulation does not improve the effect of photodynamic therapy for actinic keratosis

    DEFF Research Database (Denmark)

    Nissen, C V; Heerfordt, I M; Wiegell, S R

    2017-01-01

    BACKGROUND: Photodynamic therapy (PDT) with methyl aminolaevulinate (MAL) is highly effective for treating actinic keratosis (AK) on the face/scalp, but less effective on the extremities. Insufficient accumulation of protoporphyrin IX (PpIX) may cause these inferior efficacy rates. However...... (P = 0·001 and P = 0·002, respectively). However, the median total clearance rates did not improve accordingly: 3hC+ (55·0%), 21hC- (55·0%) and 21hC+ (53·6%). Conversely, insufficient PpIX accumulation in the 3hC- regimen led to a significantly lower clearance rate (33·3%) than the other regimens (P...

  16. Evaluation of the potential inhibitor of Ix (Pp-Ix) protoporphyrin of the genetic damage induced by gamma rays administered to different dose reasons in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Flores A, J. A.

    2016-01-01

    Ionizing radiation can damage in DNA directly or indirectly by free radicals (Rl), characterized by unstable and highly reactive. To avoid damage by Rl the cell has endogenous antioxidants such as Sod, Cat, GSH or exogenous as some vitamins, but if with these mechanisms does not reach the cell homeostasis, the consequence may be the generation of chronic-disease degenerative such as cancer. This study was conducted in order to test the inhibitory role of Rl protoporphyrin Ix (Pp-Ix), induced by 20 Gy of gamma rays administered at different dose ratios using the assay of somatic mutation and recombination in the Drosophila wing. The results indicated that 20 Gy delivered at a rate of low dose (6.659 Gy/h), caused elevated frequencies of genetic damage (p <0.001), compared with those that induced a high dose reason (1111.42 Gy/h) in larvae of 48 h old. The difference is probably due to an indirect damage by Rl; when this hypothesis was approved with the possible inhibitor role of Pp-Ix (0.69 m M), damage was increased with the two reasons of tested doses. This result may be due to: 1) the Pp-Ix is not a good inhibitor of Rl, 2) the difference in the frequency of mutation found with both dose reasons, not due to Rl so that this compound did not reduce the genetic damage, and 3) that Pp-Ix acts as pro oxidant. (Author)

  17. Cluster management.

    Science.gov (United States)

    Katz, R

    1992-11-01

    Cluster management is a management model that fosters decentralization of management, develops leadership potential of staff, and creates ownership of unit-based goals. Unlike shared governance models, there is no formal structure created by committees and it is less threatening for managers. There are two parts to the cluster management model. One is the formation of cluster groups, consisting of all staff and facilitated by a cluster leader. The cluster groups function for communication and problem-solving. The second part of the cluster management model is the creation of task forces. These task forces are designed to work on short-term goals, usually in response to solving one of the unit's goals. Sometimes the task forces are used for quality improvement or system problems. Clusters are groups of not more than five or six staff members, facilitated by a cluster leader. A cluster is made up of individuals who work the same shift. For example, people with job titles who work days would be in a cluster. There would be registered nurses, licensed practical nurses, nursing assistants, and unit clerks in the cluster. The cluster leader is chosen by the manager based on certain criteria and is trained for this specialized role. The concept of cluster management, criteria for choosing leaders, training for leaders, using cluster groups to solve quality improvement issues, and the learning process necessary for manager support are described.

  18. Identification of 16SrIX-C phytoplasmas in Argyranthemum frutescens in Italy

    Directory of Open Access Journals (Sweden)

    Luca FERRETTI

    2015-04-01

    Full Text Available Phytoplasmas are cell wall-less microorganisms associated with plant diseases worldwide. Many important food, vegetable and fruits crops as well as ornamental plants can be severely affected by these pathogens, with significant economic impacts. Phytoplasma diseases of ornamentals have been described worldwide in a wide range of plant genera, and 11 different 16Sr groups have been identified. In Italy, many ornamental plant species belonging to several botanical families have been found to be infected by phytoplasmas, classified into the ribosomal groups 16SrI, 16SrII, 16SrV and 16SrXII. During a survey carried out in commercial gardens in Rome, some marguerite daisy (Argyranthemum frutescens plants showing symptoms of phytoplasma-like disease, were collected and submitted to molecular analyses. Cloning and sequencing of the portion of the 16S rRNA gene followed by BLAST analysis, real and virtual restriction fragment length polymorphism anlaysis with AluI and RsaI, allowed assignment of the detected phytoplasma to the 16SrIX-C group (Picris echioides yellows, PEY.

  19. The KMOS Cluster Survey (KCS). II. The Effect of Environment on the Structural Properties of Massive Cluster Galaxies at Redshift 1.39 < z < 1.61

    Science.gov (United States)

    Chan, Jeffrey C. C.; Beifiori, Alessandra; Saglia, Roberto P.; Mendel, J. Trevor; Stott, John P.; Bender, Ralf; Galametz, Audrey; Wilman, David J.; Cappellari, Michele; Davies, Roger L.; Houghton, Ryan C. W.; Prichard, Laura J.; Lewis, Ian J.; Sharples, Ray; Wegner, Michael

    2018-03-01

    We present results on the structural properties of massive passive galaxies in three clusters at 1.39 R-band sizes of these galaxies are a factor of ∼2–3 smaller than their local counterparts. The slopes of the relation between the stellar mass and the light-weighted size are consistent with recent studies in clusters and the field. Their mass-weighted sizes are smaller than the rest-frame R-band sizes, with an average mass-weighted to light-weighted size ratio that varies between ∼0.45 and 0.8 among the clusters. We find that the median light-weighted size of the passive galaxies in the two more evolved clusters is ∼24% larger than that for field galaxies, independent of the use of circularized effective radii or semimajor axes. These two clusters also show a smaller size ratio than the less evolved cluster, which we investigate using color gradients to probe the underlying {M}* /{L}{{{H}}160} gradients. The median color gradients are ∇z ‑ H ∼ ‑0.4 mag dex‑1, twice the local value. Using stellar populations models, these gradients are best reproduced by a combination of age and metallicity gradients. Our results favor the minor merger scenario as the dominant process responsible for the observed galaxy properties and the environmental differences at this redshift. The environmental differences support that clusters experience accelerated structural evolution compared to the field, likely via an epoch of enhanced minor merger activity during cluster assembly. Based on observations obtained at the Very Large Telescope (VLT) of the European Southern Observatory (ESO; program IDs: 092.A-0210; 093.A-0051; 094.A-0578; 095.A-0137(A); 096.A-0189(A); 097.A-0332(A)). This work is based on observations made with the NASA/ESA HST, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program GO 13687, as well as with the CANDELS Multi-Cycle Treasury

  20. Cluster concept in multiple hadron production

    International Nuclear Information System (INIS)

    Dremin, I.M.; Quigg, C.

    1978-01-01

    The general features of high-energy collisions of elementary particles are outlined. It is argued that multiple production occurs through the production of hadronic clusters. The history and present status of the cluster concept are surveyed

  1. Exploring Relations Between BCG & Cluster Properties in the SPectroscopic IDentification of eROSITA Sources Survey from 0.05 < z < 0.3

    Science.gov (United States)

    Furnell, Kate E.; Collins, Chris A.; Kelvin, Lee S.; Clerc, Nicolas; Baldry, Ivan K.; Finoguenov, Alexis; Erfanianfar, Ghazaleh; Comparat, Johan; Schneider, Donald P.

    2018-04-01

    We present a sample of 329 low to intermediate redshift (0.05 data from ROSAT, maximum likelihood outputs from an optical cluster-finder algorithm and visual inspection. Using SDSS imaging data, we fit Sérsic profiles to our BCGs in three bands (g, r, i) with SIGMA, a GALFIT-based software wrapper. We examine the reliability of our fits by running our pipeline on ˜104 psf-convolved model profiles injected into 8 random cluster fields; we then use the results of this analysis to create a robust subsample of 198 BCGs. We outline three cluster properties of interest: overall cluster X-ray luminosity (LX), cluster richness as estimated by REDMAPPER (λ) and cluster halo mass (M200), which is estimated via velocity dispersion. In general, there are significant correlations with BCG stellar mass between all three environmental properties, but no significant trends arise with either Sérsic index or effective radius. There is no major environmental dependence on the strength of the relation between effective radius and BCG stellar mass. Stellar mass therefore arises as the most important factor governing BCG morphology. Our results indicate that our sample consists of a large number of relaxed, mature clusters containing broadly homogeneous BCGs up to z ˜ 0.3, suggesting that there is little evidence for much ongoing structural evolution for BCGs in these systems.

  2. Pain during photodynamic therapy is associated with protoporphyrin IX fluorescence and fluence rate

    DEFF Research Database (Denmark)

    Wiegell, S.R.; Skiveren, J.; Philipsen, P.A.

    2008-01-01

    and protoporphyrin IX (PpIX) fluorescence, lesion type, lesion preparation and lesion localization. Methods Twenty-six patients with actinic keratoses (AKs) in different localizations and 34 patients with facial acne vulgaris were treated with methyl aminolaevulinate-PDT. Patients with acne were illuminated using......) patients with acne had a pain score of 6 [interquart