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Sample records for h-alpha equivalent width

  1. Investigating Starburst Galaxy Emission Line Equivalent Widths

    Meskhidze, Helen; Richardson, Chris T.

    2016-01-01

    Modeling star forming galaxies with spectral synthesis codes allows us to study the gas conditions and excitation mechanisms that are necessary to reproduce high ionization emission lines in both local and high-z galaxies. Our study uses the locally optimally-emitting clouds model to develop an atlas of starburst galaxy emission line equivalent widths. Specifically, we address the following question: What physical conditions are necessary to produce strong high ionization emission lines assuming photoionization via starlight? Here we present the results of our photoionization simulations: an atlas spanning 15 orders of magnitude in ionizing flux and 10 orders of magnitude in hydrogen density that tracks over 150 emission lines ranging from the UV to the near IR. Each simulation grid contains ~1.5x104 photoionization models calculated by supplying a spectral energy distribution, grain content, and chemical abundances. Specifically, we will be discussing the effects on the emission line equivalent widths of varying the metallicity of the cloud, Z = 0.2 Z? to Z = 5.0 Z?, and varying the star-formation history, using the instantaneous and continuous evolution tracks and the newly released Starburst99 Geneva rotation tracks.

  2. The Photometric and Kinematic Structure of Face-On Disk Galaxies. I. Sample Definition, H-alpha Integral Field Spectroscopy, and HI Line-Widths

    Andersen, D R; Sparke, L S; Gallagher, J S; Wilcots, E M; Van Driel, W; Monnier-Ragaigne, D; Andersen, David R.; Bershady, Matthew A.; Sparke, Linda S.; Gallagher, John S.; Wilcots, Eric M.; Driel, Wim van; Monnier-Ragaigne, Delphine

    2006-01-01

    We present a survey of the photometric and kinematic properties of 39 nearby, nearly face-on disk galaxies. Our approach exploits echelle-resolution integral-field spectroscopy of the H-alpha regions, obtained with DensePak on the WIYN 3.5m telescope Bench Spectrograph. This data is complemented by HI line-profiles observed with the Nancay radio telescope for 25 of these sample galaxies. Twelve additional line-widths are available for sample galaxies from the literature. In this paper, we introduce the goals of this survey, define the sample selection algorithm, and amass the integral field spectroscopic data and HI line-widths. We establish spatially-integrated H-alpha line-widths for the sample. We test the veracity of these spatially-integrated line profiles by convolving narrow-band imaging data with velocity field information for one of the sample galaxies, PGC 38268, and also by comparing to HI line profiles. We find HI and H-alpha line profiles to be similar in width but different in shape, indicating ...

  3. H I Lyman-alpha equivalent widths of stellar populations

    We have compiled a library of stellar Lyman-alpha (Lyα) equivalent widths in O and B stars using the model atmosphere codes CMFGEN and TLUSTY, respectively. The equivalent widths range from about 0 to 30 Å in absorption for early-O to mid-B stars. The purpose of this library is for the prediction of the underlying stellar Lyα absorption in stellar populations of star-forming galaxies with nebular Lyα emission. We implemented the grid of individual equivalent widths into the Starburst99 population synthesis code to generate synthetic Lyα equivalent widths for representative star formation histories. A starburst observed after 10 Myr will produce a stellar Lyα line with an equivalent width of ∼ – 10 ± 4 Å in absorption for a Salpeter initial mass function. The lower value (deeper absorption) results from an instantaneous burst, and the higher value (shallower line) from continuous star formation. Depending on the escape fraction of nebular Lyα photons, the effect of stellar Lyα on the total profile ranges from negligible to dominant. If the nebular escape fraction is 10%, the stellar absorption and nebular emission equivalent widths become comparable for continuous star formation at ages of 10-20 Myr.

  4. H I Lyman-alpha equivalent widths of stellar populations

    Pea-Guerrero, Mara A.; Leitherer, Claus, E-mail: pena@stsci.edu, E-mail: leitherer@stsci.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2013-12-01

    We have compiled a library of stellar Lyman-alpha (Ly?) equivalent widths in O and B stars using the model atmosphere codes CMFGEN and TLUSTY, respectively. The equivalent widths range from about 0 to 30 in absorption for early-O to mid-B stars. The purpose of this library is for the prediction of the underlying stellar Ly? absorption in stellar populations of star-forming galaxies with nebular Ly? emission. We implemented the grid of individual equivalent widths into the Starburst99 population synthesis code to generate synthetic Ly? equivalent widths for representative star formation histories. A starburst observed after 10 Myr will produce a stellar Ly? line with an equivalent width of ? 10 4 in absorption for a Salpeter initial mass function. The lower value (deeper absorption) results from an instantaneous burst, and the higher value (shallower line) from continuous star formation. Depending on the escape fraction of nebular Ly? photons, the effect of stellar Ly? on the total profile ranges from negligible to dominant. If the nebular escape fraction is 10%, the stellar absorption and nebular emission equivalent widths become comparable for continuous star formation at ages of 10-20 Myr.

  5. PACCE: Perl Algorithm to Compute Continuum and Equivalent Widths

    Riffel, Rogério

    2011-01-01

    We present Perl Algorithm to Compute continuum and Equivalent Widths (pacce). We describe the methods used in the computations and the requirements for its usage. We compare the measurements made with pacce and "manual" ones made using iraf splot task. These tests show that for SSP models the equivalent widths strengths are very similar (differences <0.2A) for both measurements. In real stellar spectra, the correlation between both values is still very good, but with differences of up to 0.5A. pacce is also able to determine mean continuum and continuum at line center values, which are helpful in stellar population studies. In addition, it is also able to compute the uncertainties in the equivalent widths using photon statistics. The code is made available for the community through the web at http://www.if.ufrgs.br/~riffel/software.html.

  6. Measuring Global Galaxy Metallicities Using Emission Line Equivalent Widths

    Kobulnicky, Chip; Phillips, Andrew

    2003-01-01

    We develop a prescription for estimating the interstellar medium oxygen abundances of distant star-forming galaxies using the ratio EWR_{23} formed from the equivalent widths of the [O II] 3727, [O III] 4959,5007 and Hbeta nebular emission lines. This EWR_{23} approach essentially identical to the widely-used R_{23} method of Pagel et. al (1979). Using data from three spectroscopic surveys of nearby galaxies, we conclude that the emission line equivalent width ratios are a good substitute for...

  7. A new code for automatic determination of equivalent widths: Automatic Routine for line Equivalent widths in stellar Spectra (ARES)

    Sousa, S G; Israelian, G; Mayor, M; Monteiro, M J P F G

    2007-01-01

    We present a new automatic code (ARES) for determining equivalent widths of the absorption lines present in stellar spectra. We also describe its use for determining fundamental spectroscopic stellar parameters. The code is written in C++ based on the standard method of determining EWs and is available for the community. The code automates the manual procedure that the users normally carry out when using interactive routines such as the splot routine implemented in IRAF. We test the code using both simulated and real spectra with different levels of resolution and noise and comparing its measurements to the manual ones obtained in the standard way. The results shows a small systematic difference, always below 1.5m\\AA. This can be explained by errors in the manual measurements caused by subjective continuum determination. The code works better and faster than others tested before.

  8. Predicting dust extinction properties of star-forming galaxies from H-alpha/UV ratio

    Koyama, Yusei; Hayashi, Masao; Shimakawa, Rhythm; Yamamura, Issei; Egusa, Fumi; Oi, Nagisa; Tanaka, Ichi; Tadaki, Ken-ichi; Takita, Satoshi; Makiuti, Sin'itirou

    2015-01-01

    Using star-forming galaxies sample in the nearby Universe (0.02H-alpha-to-FUV flux ratio. We find that the H-alpha dust extinction (A(Ha)) derived with H-alpha/H-beta ratio (Balmer decrement) increases with increasing H-alpha/UV ratio as expected, but there remains a considerable scatter around the relation, which is largely dependent on stellar mass and/or H-alpha equivalent width (EW(Ha)). At fixed H-alpha/UV ratio, galaxies with higher stellar mass (or galaxies with lower EW(Ha)) tend to be more highly obscured by dust. We quantify this trend and establish an empirical calibration for predicting A(Ha) with a combination of H-alpha/UV ratio, stellar mass and EW(Ha), with which we can successfully reduce the systematic uncertainties accompanying the simple H-alpha/UV approach by ~15-30%. The new recipes proposed in this study will provide a conveni...

  9. Comparison of the equivalent width, the autocorrelation width, and the variance as figures of merit for XPS narrow scans

    Highlights: • We apply the equivalent and autocorrelation widths and variance to XPS narrow scans. • This approach is complementary to traditional peak fitting methods. • It is bias free and responsive to subtle chemical changes in spectra. • It has the potential for machine interpretation of spectra and quality control. • It has the potential for analysis of complex spectra and tracking charging/artifacts. - Abstract: X-ray photoelectron spectroscopy (XPS) is widely used in surface and materials laboratories around the world. It is a near surface technique, providing detailed chemical information about samples in the form of survey and narrow scans. To extract the maximum amount of information about materials it is often necessary to peak fit XPS narrow scans. And while indispensable to XPS data analysis, even experienced practitioners can struggle with their peak fitting. In our previous publication, we introduced the equivalent width (EWXPS) as both a possible machine automated method, one that requires less expert judgment for characterizing XPS narrow scans, and as an approach that may be well suited for the analysis of complex spectra. The EWXPS figure of merit was applied to four different data sets. However, as previously noted, other width functions are also regularly employed for analyzing functions. Here we evaluate two other width functions for XPS narrow scan analysis: the autocorrelation width (AWXPS) and the variance (σXPS2). These widths were applied to the same four sets of spectra studied before: (a) four C 1s narrow scans of ozone-treated carbon nanotubes (CNTs) (EWXPS: ∼2.11–2.16 eV, AWXPS: ∼3.9–4.1 eV, σXPS2: ∼5.0–5.2 eV, and a modified form of σXPS2, denoted σXPS2*: ∼6.3–6.8 eV), (b) silicon wafers with different oxide thicknesses (EWXPS: ∼1.5–2.9 eV, AWXPS: ∼2.28–4.9, and σXPS2: ∼0.7–4.9 eV), (iii) hydrogen-terminated silicon surfaces, before and after modification with pentyl groups, and after annealing of the pentyl-terminated surface (EWXPS: ∼0.7–1.0 eV, AWXPS: ∼1.2–1.6 eV, and σXPS2: ∼0.12–0.19 eV), and (iv) C 1s narrow scans from five different nanodiamond samples, three of which showed charging (EWXPS: ∼2.6–4.8 eV, AWXPS: ∼3.8–6.9 eV, and σXPS2: ∼1.6–4.2 eV). All three of the width functions showed similar trends, except in the case of the C 1s spectra of the CNT samples, which were the most complex spectra evaluated, where σXPS2 showed poor correlation with the corresponding O/C ratios. Accordingly, we favor EWXPS and AWXPS. EWXPS is advantageous because it is conceptually simple, giving the most intuitive results. AWXPS has the advantage of not requiring the user to specify the height of the function at its maximum, which will be affected by noise. Because these functions are based on different mathematical operations/algorithms, best practices may involve the calculation of both widths for a set of narrow scans. The standard deviation, σXPS, i.e., the square root of the variance, was also examined. As expected, it gave results similar to σXPS2

  10. Bayesian Redshift Classification of Emission-line Galaxies with Photometric Equivalent Widths

    Leung, Andrew S.; Acquaviva, Viviana; Gawiser, Eric; Ciardullo, Robin; Komatsu, Eiichiro; Zeimann, Gregory R.; Bridge, Joanna S.; Feldmeier, John J.; Finkelstein, Steven L.; Gebhardt, Karl; Gronwall, Caryl; Hagen, Alex; Gary J. Hill; Schneider, Donald P.

    2015-01-01

    We present a Bayesian approach to the redshift classification of emission-line galaxies when only a single emission line is detected spectroscopically. We consider the case of surveys for high-redshift ${\\rm Ly{\\alpha}}$-emitting galaxies (LAEs), which have traditionally been classified via an inferred rest-frame equivalent width $(W_{\\rm Ly\\alpha})$ greater than $20 {\\rm \\,\\AA}$. Our Bayesian method relies on known prior probabilities in measured emission-line luminosity functions and equiva...

  11. The reddening law of Type Ia Supernovae: separating intrinsic variability from dust using equivalent widths

    Chotard, N; Aldering, G; Antilogus, P; Aragon, C; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Childress, M; Copin, Y; Fakhouri, H K; Hsiao, E Y; Kerschhaggl, M; Kowalski, M; Loken, S; Nugent, P; Paech, K; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Runge, K; Scalzo, R; Smadja, G; Tao, C; Thomas, R C; Weaver, B A; Wu, C

    2011-01-01

    We employ 76 type Ia supernovae with optical spectrophotometry within 2.5 days of B-band maximum light obtained by the Nearby Supernova Factory to derive the impact of Si and Ca features on supernovae intrinsic luminosity and determine a dust reddening law. We use the equivalent width of Si II {\\lambda}4131 in place of light curve stretch to account for first-order intrinsic luminosity variability. The resultant empirical spectral reddening law exhibits strong features associated with Ca II and Si II {\\lambda}6355. After applying a correction based on the Ca II H&K equivalent width we find a reddening law consistent with a Cardelli extinction law. Using the same input data, we compare this result to synthetic rest-frame UBVRI-like photometry in order to mimic literature observations. After corrections for signatures correlated with Si II {\\lambda}4131 and Ca II H&K equivalent widths, and introducing an empirical correlation between colors, we determine the dust component in each band. We find a value ...

  12. On the H$\\alpha$ Behaviour of Blue Supergiants: Rise and Fall over the Bi-stability Jump

    Petrov, Blagovest; Gräfener, Götz

    2014-01-01

    The evolutionary state of blue supergiants is still unknown. Stellar wind mass loss is one of the dominant processes determining the evolution of massive stars, and it may provide clues on the evolutionary properties of blue supergiants. As the H$\\alpha$ line is the most oft-used mass-loss tracer in the OB-star regime, we provide a detailed analysis of the H$\\alpha$ line for OB supergiant models over an $T_{\\rm eff}$ range between 30000 and 12500K. We find a maximum in the H$\\alpha$ equivalent width at 22500 K - at the location of the bi-stability jump. The H$\\alpha$ line-profile behaviour is characterised by two branches of $T_{\\rm eff}$: (i) a "hot" branch between 30000 and 22500 K, where H$\\alpha$ emission becomes stronger with decreasing $T_{\\rm eff}$, and (ii) a "cool" branch between 22500 and 12500 K, where the line becomes weaker. Our models show that this non-monotonic H$\\alpha$ behaviour is related to the optical depth of Ly$\\alpha$, finding that at the "cool" branch the population of the 2nd level o...

  13. H$\\alpha$ and EUV observations of a partial CME

    Christian, Damian J; Antolin, Patrick; Mathioudakis, Mihalis

    2015-01-01

    We have obtained H$\\alpha$ high spatial and time resolution observations of the upper solar chromosphere and supplemented these with multi-wavelength observations from the Solar Dynamic Observatory (SDO) and the {\\it Hinode} ExtremeUltraviolet Imaging Spectrometer (EIS). The H$\\alpha$ observations were conducted on 11 February 2012 with the Hydrogen-Alpha Rapid Dynamics Camera (HARDcam) instrument at the National Solar Observatory's Dunn Solar Telescope. Our H$\\alpha$ observations found large downflows of chromospheric material returning from coronal heights following a failed prominence eruption. We have detected several large condensations ("blobs") returning to the solar surface at velocities of $\\approx$200 km s$^{-1}$ in both H$\\alpha$ and several SDO AIA band passes. The average derived size of these "blobs" in H$\\alpha$ is 500 by 3000 km$^2$ in the directions perpendicular and parallel to the direction of travel, respectively. A comparison of our "blob" widths to those found from coronal rain, indicate...

  14. Bayesian Redshift Classification of Emission-line Galaxies with Photometric Equivalent Widths

    Leung, Andrew S; Gawiser, Eric; Ciardullo, Robin; Komatsu, Eiichiro; Zeimann, Gregory R; Bridge, Joanna S; Feldmeier, John J; Finkelstein, Steven L; Gebhardt, Karl; Gronwall, Caryl; Hagen, Alex; Hill, Gary J; Schneider, Donald P

    2015-01-01

    We present a Bayesian approach to the redshift classification of emission-line galaxies when only a single emission line is detected spectroscopically. We consider the case of surveys for high-redshift ${\\rm Ly{\\alpha}}$-emitting galaxies (LAEs), which have traditionally been classified via an inferred rest-frame equivalent width $(W_{\\rm Ly\\alpha})$ greater than $20 {\\rm \\,\\AA}$. Our Bayesian method relies on known prior probabilities in measured emission-line luminosity functions and equivalent width distributions for the galaxy populations in question, and it returns the probability that an object is an LAE given the characteristics observed. This approach will be directly relevant for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), which seeks to classify $\\sim$$10^6$ emission-line galaxies into LAEs and low-redshift [O II] emitters. For a simulated HETDEX catalog with realistic measurement noise, our Bayesian method recovers $86\\%$ of LAEs missed by the traditional $W_{\\rm Ly\\alpha} > 20 {\\rm...

  15. H-alpha as a Luminosity Class Diagnostic for K- and M-type Stars

    Jennings, Jeff

    2016-01-01

    We have identified the H-alpha absorption feature as a new spectroscopic diagnostic of luminosity class in K- and M-type stars. From high-resolution spectra of 19 stars with well-determined physical properties (including effective temperatures and stellar radii), we measured equivalent widths for H-alpha and the Ca II triplet and examined their dependence on both luminosity class and stellar radius. H-alpha shows a strong relation with both luminosity class and radius that extends down to late M spectral types. This behavior in H-alpha has been predicted as a result of the density-dependent overpopulation of the metastable 2S level in hydrogen, an effect that should become dominant for Balmer line formation in non-LTE conditions. We conclude that this new metallicity-insensitive diagnostic of luminosity class in cool stars could serve as an effective means of discerning between populations such as Milky Way giants and supergiant members of background galaxies.

  16. VizieR Online Data Catalog: Equivalent width of 21 RR Lyrae stars (Pancino+, 2015)

    Pancino, E.; Britavskiy, N.; Romano, D.; Cacciari, C.; Mucciarelli, A.; Clementini, G.

    2015-02-01

    Equivalent widths and atomic data of the absorption lines used in the abundance analysis, for each separate exposure at different phases. Observations of 15 RR Lyrae stars (DR And, X Ari, TW Boo, RZ Cam, RX Cet, U Com, RV CrB, SW CVn, UZ CVn, AE Dra, SZ Gem, VX Her, DH Hya, TU UMa, and RV UMa) and one BL Her star (UY Eri) were carried out with SARG@TNG, operated on the island of La Palma, Spain, during two separate runs in 2009 March and between September and November. Eight stars (SW Aqr, TW Cap, DH Hya, V Ind, SS Leo, V716 Oph, BK Tuc, and UV Vir) were observed with UVES@VLT, between 2009 April and August in service mode. (3 data files).

  17. On the (Non-)Enhancement of the Ly? Equivalent Width by a Multiphase Interstellar Medium

    Laursen, Peter; Duval, F.; stlin, G.

    2013-01-01

    It has been suggested that radiative transfer effects may explain the unusually high equivalent widths (EWs) of the Lya line, observed occasionally from starburst galaxies, especially at high redshifts. If the dust is locked up inside high-density clouds dispersed in an empty intercloud medium, the...... Lya photons could scatter off of the surfaces of the clouds, effectively having their journey confined to the dustless medium. The continuum radiation, on the other hand, does not scatter, and would thus be subject to absorption inside the clouds. This scenario is routinely invoked when Lya EWs higher...... than what is expected theoretically are observed, although the ideal conditions under which the results are derived usually are not considered. Here we systematically examine the relevant physical parameters in this idealized framework, testing whether any astrophysically realistic scenarios may lead...

  18. Lyman Alpha Emitters in Hierarchical Galaxy Formation II. UV Continuum Luminosity Function and Equivalent Width Distribution

    Kobayashi, Masakazu A R; Nagashima, Masahiro

    2009-01-01

    We present theoretical predictions of UV continuum luminosity function (UV LF) and Lya equivalent width (EW) distribution of Lyman alpha emitters (LAEs) in the framework of the hierarchical clustering model of galaxy formation. The model parameters about LAEs were determined by fitting to the observed Lya LF at z=5.7 in our previous study, and the fit indicates that extinction of Lya photons by dust is significantly less effective than that of UV continuum photons, implying clumpy dust distribution in interstellar medium. We then compare the predictions about UV LFs and EW distributions with a variety of observations at z~3-6, allowing no more free parameters and paying careful attention to the selection conditions of LAEs in each survey. We find that the predicted UV LFs and EW distributions are in nice agreement with observed data, and especially, our model naturally reproduces the existence of large EW LAEs(> 240 A) without introducing Pop III stars or top-heavy initial mass function. We show that both the...

  19. The equivalent width as a figure of merit for XPS narrow scans

    Highlights: • We introduce a new figure of merit for XPS narrow scans: the equivalent width (EWXPS). • EWXPS is less subjective and involves lesser user bias than traditional peak fitting. • EWXPS is responsive to changes in chemical states of materials. • EWXPS could be used for quality control and comparing spectra from similar samples. • EWXPS has the potential to be part of an expert software system for machine interpretation of spectra. - Abstract: X-ray Photoelectron Spectroscopy (XPS) is a widely used surface analytical tool that provides information about the near surface regions of materials. And while indispensable for XPS data analysis, peak fitting of narrow scans is often a fairly subjective exercise. Herein we introduce the equivalent width (EW) as an additional and less subjective figure of merit for XPS narrow scans. We believe that this parameter will prove particularly useful for analyzing series of similar or nominally identical spectra, perhaps as a component of an expert software system for the machine interpretation of spectra. It also appears to be useful, shedding light on the chemical state of materials, when additional information about a sample is known. The EWXPS is simply defined as the area of a narrow scan divided by the height of the maximum of its peak envelope. To limit any ambiguity in EWXPS for a series of spectra, we may also list the peak position of the maximum of the envelope (PEmax). The potential usefulness and limitations of the EWXPS and PEmax parameters are demonstrated by their application to the narrow scans of: (i) four sets of ozone-treated carbon nanotubes (EWXPS ∼ 2.11–2.16 eV for a Shirley background, and up to 2.88 eV for no background, PEmax ∼ 284.4–284.5 eV), (ii) a series of silicon wafers with different oxide thicknesses (EWXPS ∼ 1.5–2.8 eV, PEmax ∼ 99–103 eV), (iii) hydrogen-terminated silicon before and after derivatization with pentyl groups, and after annealing of the pentyl-modified material (EWXPS ∼ 0.7–1.0 eV, PEmax ∼ 25.9–26.1 eV), and (iv) five nanodiamond samples, where three of the spectra showed charging (EWXPS ∼ 2.6–4.9 eV, PEmax ∼ 272.7–293.9 eV). In this final example, EWXPS was plotted against PEmax to identify the region corresponding to the materials that showed the least charging. EWXPS and PEmax appear to correlate with the expected chemistries of all the systems studied. We calculate EWXPS using a Shirley baseline and with no baseline at all. In setting the baseline limits for EWXPS, we consider the derivative of C 1s narrow scans. We also show the application of EWXPS to single, fitted components within a narrow scan

  20. The equivalent width as a figure of merit for XPS narrow scans

    Singh, Bhupinder [Department of Chemistry and Biochemistry, C-100 BNSN, Brigham Young University, Provo, UT 84602 (United States); Velzquez, Daniel [Department of Physics, Illinois Institute of Technology, Chicago, IL 60616 (United States); Terry, Jeff, E-mail: terryj@iit.edu [Department of Physics, Illinois Institute of Technology, Chicago, IL 60616 (United States); Linford, Matthew R., E-mail: mrlinford@chem.byu.edu [Department of Chemistry and Biochemistry, C-100 BNSN, Brigham Young University, Provo, UT 84602 (United States)

    2014-12-15

    Highlights: We introduce a new figure of merit for XPS narrow scans: the equivalent width (EW{sub XPS}). EW{sub XPS} is less subjective and involves lesser user bias than traditional peak fitting. EW{sub XPS} is responsive to changes in chemical states of materials. EW{sub XPS} could be used for quality control and comparing spectra from similar samples. EW{sub XPS} has the potential to be part of an expert software system for machine interpretation of spectra. - Abstract: X-ray Photoelectron Spectroscopy (XPS) is a widely used surface analytical tool that provides information about the near surface regions of materials. And while indispensable for XPS data analysis, peak fitting of narrow scans is often a fairly subjective exercise. Herein we introduce the equivalent width (EW) as an additional and less subjective figure of merit for XPS narrow scans. We believe that this parameter will prove particularly useful for analyzing series of similar or nominally identical spectra, perhaps as a component of an expert software system for the machine interpretation of spectra. It also appears to be useful, shedding light on the chemical state of materials, when additional information about a sample is known. The EW{sub XPS} is simply defined as the area of a narrow scan divided by the height of the maximum of its peak envelope. To limit any ambiguity in EW{sub XPS} for a series of spectra, we may also list the peak position of the maximum of the envelope (PE{sub max}). The potential usefulness and limitations of the EW{sub XPS} and PE{sub max} parameters are demonstrated by their application to the narrow scans of: (i) four sets of ozone-treated carbon nanotubes (EW{sub XPS} ? 2.112.16 eV for a Shirley background, and up to 2.88 eV for no background, PE{sub max} ? 284.4284.5 eV), (ii) a series of silicon wafers with different oxide thicknesses (EW{sub XPS} ? 1.52.8 eV, PE{sub max} ? 99103 eV), (iii) hydrogen-terminated silicon before and after derivatization with pentyl groups, and after annealing of the pentyl-modified material (EW{sub XPS} ? 0.71.0 eV, PE{sub max} ? 25.926.1 eV), and (iv) five nanodiamond samples, where three of the spectra showed charging (EW{sub XPS} ? 2.64.9 eV, PE{sub max} ? 272.7293.9 eV). In this final example, EW{sub XPS} was plotted against PE{sub max} to identify the region corresponding to the materials that showed the least charging. EW{sub XPS} and PE{sub max} appear to correlate with the expected chemistries of all the systems studied. We calculate EW{sub XPS} using a Shirley baseline and with no baseline at all. In setting the baseline limits for EW{sub XPS}, we consider the derivative of C 1s narrow scans. We also show the application of EW{sub XPS} to single, fitted components within a narrow scan.

  1. From HI to Stars: HI Depletion in Starbursts and Star-Forming Galaxies in the ALFALFA H-alpha Survey

    Jaskot, A E; Salzer, J J; Van Sistine, A; Bell, E F; Haynes, M P

    2015-01-01

    HI in galaxies traces the fuel for future star formation and reveals the effects of feedback on neutral gas. Using a statistically uniform, HI-selected sample of 565 galaxies from the ALFALFA H-alpha survey, we explore HI properties as a function of star formation activity. ALFALFA H-alpha provides R-band and H-alpha imaging for a volume-limited subset of the 21-cm ALFALFA survey. We identify eight starbursts based on H-alpha equivalent width and six with enhanced star formation relative to the main sequence. Both starbursts and non-starbursts have similar HI to stellar mass ratios (MHI/M*), which suggests that feedback is not depleting the starbursts' HI. Consequently, the starbursts do have shorter HI depletion times (t_dep), implying more efficient HI-to-H2 conversion. While major mergers likely drive this enhanced efficiency in some starbursts, the lowest mass starbursts may experience periodic bursts, consistent with enhanced scatter in t_dep at low M*. Two starbursts appear to be pre-coalescence mergers...

  2. Discovery of Massive, Mostly Star-formation Quenched Galaxies with Extremely Large Lyman-alpha Equivalent Widths at z ~ 3

    Taniguchi, Yoshiaki; Kobayashi, Masakazu A R; Nagao, Tohru; Shioya, Yasuhiro; Scoville, Nick Z; Sanders, David B; Capak, Peter L; Koekemoer, Anton M; Toft, Sune; McCracken, Henry J; Fevre, Olivier Le; Tasca, Lidia; Sheth, Kartik; Renzini, Alvio; Lilly, Simon; Carollo, Marcella; Kovac, Katarina; Ilbert, Olivier; Schinnerer, Eva; Fu, Hai; Tresse, Laurence; Griffiths, Richard E; Civano, Francesca

    2015-01-01

    We report a discovery of 6 massive galaxies with both extremely large Lya equivalent width and evolved stellar population at z ~ 3. These MAssive Extremely STrong Lya emitting Objects (MAESTLOs) have been discovered in our large-volume systematic survey for strong Lya emitters (LAEs) with twelve optical intermediate-band data taken with Subaru/Suprime-Cam in the COSMOS field. Based on the SED fitting analysis for these LAEs, it is found that these MAESTLOs have (1) large rest-frame equivalent width of EW_0(Lya) ~ 100--300 A, (2) M_star ~ 10^10.5--10^11.1 M_sun, and (3) relatively low specific star formation rates of SFR/M_star ~ 0.03--1 Gyr^-1. Three of the 6 MAESTLOs have extended Ly$\\alpha$ emission with a radius of several kpc although they show very compact morphology in the HST/ACS images, which correspond to the rest-frame UV continuum. Since the MAESTLOs do not show any evidence for AGNs, the observed extended Lya emission is likely to be caused by star formation process including the superwind activit...

  3. Grid of theoretical NLTE equivalent widths of four Ba II lines and barium abundance in cool stars

    Korotin, S A; Hansen, C J; Caffau, E; Bonifacio, P; Spite, M; Spite, F; Francois, P

    2015-01-01

    We present a grid of computed non-local thermodynamic equilibrium (NLTE) equivalent widths (EW) and NLTE abundance corrections for four Ba II lines: 4554, 5853, 6141, and 6496 A. The grid can be useful in deriving the NLTE barium abundance in stars having parameters in the following ranges: effective temperature from 4000 K to 6500 K, surface gravity log g from 0 to 5, microturbulent velocity 0 km s^-1 to 3 km s^-1, metallicity [Fe/H] from -2 to +0.5, and [Ba/Fe] from -0.4 to +0.6. The NLTE abundance can be either derived by EW interpolation (using the observed Ba II line EW) or by using the NLTE correction applied to a previously determined LTE abundance. Ba II line equivalent widths and the NLTE corrections were calculated using the updated MULTI code and the Ba II atomic model that was previously applied to determine the NLTE barium abundance in different types of stars. The grid is available on-line through the web, and we find that the grid Ba NLTE corrections are almost as accurate as direct NLTE profil...

  4. The H alpha Galaxy Survey. VIII. Close companions and interactions, and the definition of starbursts

    Knapen, Johan H

    2009-01-01

    (Shortened) We consider the massive star formation properties, radial profiles, and atomic gas masses of those galaxies in our H alpha Galaxy Survey, a representative sample of the local Universe of 327 disk galaxies, that have close companion galaxies, in comparison with a matched control sample of galaxies without companions. We find that the presence of a close companion raises the star formation rate by a factor of just under two, while increasing hardly at all the equivalent width of the H alpha emission. This means that although statistically galaxies with close companions form stars at a higher rate, they do this over extended periods of time, and not as bursts. We find no significant increase in the central concentration of the star formation as a result of the presence of a close companion. The fraction of truly interacting or merging galaxies is very small in the local Universe, at around 2%, and possibly 4% of bright galaxies. Most of these interacting galaxies currently have unremarkable star form...

  5. Solar Imagery - Chromosphere - H-Alpha

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of H-alpha photographic datasets contributed by a number of national and private solar observatories located worldwide. Solar...

  6. High-Resolution Near-Infrared Spectroscopy of an Equivalent Width-Selected Sample of Starbursting Dwarf Galaxies

    Maseda, Michael V.; VanDerWeL, Arjen; DaChuna, Elisabete; Rix, Hans-Walter; Pacafichi, Camilla; Momcheva, Ivelina; Brammer, Gabriel B.; Franx, Marijn; VanDokkum, Pieter; Bell, Eric F.; Ferguson, Harry C.; Fumagalli, Mattia; Grogin, Norman A.; Kocevski, Dale D.; Koekemoer, Anton M.; Lundgren, Britt F.; Marchesini, Danilo; Nelson, Erica J.; Patel, Shannon; Skelton, Rosalind E.; Straughn, Amber N.; Trump, Jonathan R.; Weiner, Benjamin J.; Whitaker, Katherine E.; Wuyts, Stijn

    2013-01-01

    Spectroscopic observations from the Large Binocular Telescope and the Very Large Telescope reveal kinematically narrow lines (approx. 50 km/s) for a sample of 14 Extreme Emission Line Galaxies (EELGs) at redshifts 1.4 < zeta < 2.3. These measurements imply that the total dynamical masses of these systems are low ( 3 × 10(exp 9) M). Their large [O III]5007 equivalent widths (500 - 1100 A) and faint blue continuum emission imply young ages of 10-100 Myr and stellar masses of 10(exp 8)-10(exp 9) M, confirming the presence of a violent starburst. The stellar mass formed in this vigorous starburst phase thus represents a large fraction of the total (dynamical) mass, without a significantly massive underlying population of older stars. The occurrence of such intense events in shallow potentials strongly suggests that supernova-driven winds must be of critical importance in the subsequent evolution of these systems.

  7. Emission-line stars discovered in the UKST H-alpha survey of the Large Magellanic Cloud; Part 1: Hot stars

    Reid, Warren A

    2012-01-01

    We present new, accurate positions, spectral classifications, radial and rotational velocities, H-alpha fluxes, equivalent widths and B,V,I,R magnitudes for 579 hot emission-line stars (classes B0 - F9) in the Large Magellanic Cloud which include 469 new discoveries. Candidate emission line stars were discovered using a deep, high resolution H-alpha map of the central 25 deg2 of the LMC obtained by median stacking a dozen 2 hour H-alpha exposures taken with the UK Schmidt Telescope. Spectroscopic follow-up observations on the AAT, UKST, VLT, the SAAO 1.9m and the MSSSO 2.3m telescope have established the identity of these faint sources down to magnitude R~23 for H-alpha (4.5 x 10^-17 ergs cm^2 s^-1 Ang). Confirmed emission-line stars have been assigned an underlying spectral classification through cross-correlation against 131 absorption line template spectra covering the range O1 to F8. We confirm 111 previously identified emission line stars and 64 previously known variable stars with spectral types hotter ...

  8. DEFPOS H${\\alpha}$ Observations of W80 Complex

    Aksaker, Naz\\im

    2012-01-01

    We present H${\\alpha}$ emission line measurements of the W80 nebular complex. A total of 26 regions have been observed inside the nebula with the Dual Etalon Fabry-Perot Optical Spectrometer (DEFPOS) system at the f/48 Coude focus of 150 cm RTT150 telescope located at TUBITAK National Observatory (TUG) in Antalya/Turkey. The intensities, the local standard of rest (LSR) velocities ($V_{LSR}$), heliocentric radial velocities ($V_{HEL}$) and the linewidths at Full Width at Half Maximum (FWHM) of the H${\\alpha}$ emission lines have been determined from these observations. They lie in the range of 259 to 1159 Rayleigh {1R = 10$^{6}/4\\pi$ photons cm$^{-2}$ sr$^{-1}$ s$^{-1}$ = 2.4110$^{-7}$ erg cm$^{-2}$ sr$^{-1}$ s$^{-1}$ at H${\\alpha}$.} (R), 4 to 12 km s$^{-1}$ and 44 to 55 km s$^{-1}$, respectively. The radial velocity measurements show that there are several maxima and minima inside the W80. The new results confirm the literature that complex seems to be rather a uniform in radial velocity and no seen turbule...

  9. Temporal evolution of mottles observed in H_alpha

    Bostanci, Z F; Erdogan, Nurol Al

    2007-01-01

    In April 2002, H_alpha observations of the solar chromosphere with high spatial and spectral resolution were obtained with the Gottingen Fabry-Perot Spectrometer mounted in the Vacuum Tower Telescope (VTT) at the Observatorio del Teide/Tenerife. In this work, we analyze a short time sequence of a quiet region with chains of mottles. Some physical parameters of dark mottles are determined by using Beckers' cloud model which takes the source function, the Doppler width, and the velocity to be constant within the cloud along the line of sight. Here, we present the results of our study.

  10. H-alpha Observations of MKW10

    Johnson, Harold; Coble, Kimberly A.; Koopmann, Rebecca A.; Durbala, Adriana; Undergraduate ALFALFA Team

    2016-01-01

    As part of the Undergraduate ALFALFA Team project looking at clusters and groups of galaxies to investigate the effects of environment on star formation, we analyzed H-alpha and R-band observations of the group MKW10 from the WIYN 0.9-m telescope with MOSAIC camera at Kitt Peak. We continuum-subtract the H-alpha images by scaling and subtracting the broadband R images. This process includes: determining the seeing of each image by calculating the FWHM values of several stars in the image; convolving all images to the worst seeing; stacking images for each filter; subtracting sky background; scaling the R image to H-alpha; and subtracting the scaled R from H-alpha. We then use the H-alpha-continuum-subtracted image to perform surface photometry of individual galaxies in MKW10. The data will be used to determine star formation rates and distributions of galaxies in this group environment and will be compared to results for galaxies in other UAT group and cluster environments. Analysis is ongoing.This work has been supported by NSF grant AST-1211005 and the Illinois Space Grant Consortium.

  11. Scale heights and equivalent widths of the iron K-shell lines in the Galactic diffuse X-ray emission

    Yamauchi, Shigeo; Nobukawa, Masayoshi; Uchiyama, Hideki; Koyama, Katsuji

    2016-01-01

    This paper reports the analysis of the X-ray spectra of the Galactic diffuse X-ray emission (GDXE) in the Suzaku archive. The fluxes of the Fe I K alpha (6.4 keV), Fe XXV,He alpha (6.7 keV) and Fe XXVI Ly alpha (6.97 keV) lines are separately determined. From the latitude distributions, we confirm that the GDXE is decomposed into the Galactic center (GCXE), the Galactic bulge (GBXE) and the Galactic ridge (GRXE) X-ray emissions. The scale heights (SHs) of the Fe XXV He alpha line of the GCXE, GBXE and GRXE are determined to be ~40, ~310 and ~140 pc, while those of the Fe I K alpha line are ~30, ~160 and ~70 pc, respectively. The mean equivalent widths (EWs) of the sum of the Fe XXV He alpha and Fe XXVI Ly alpha lines are ~750 eV, ~600 eV and ~550 eV, while those of the Fe I K alpha line are ~150~eV, ~60~eV and ~100~eV for the GCXE, GBXE and GRXE, respectively. The origin of the GBXE, GRXE and GCXE is separately discussed based on the new results of the SHs and EWs, in comparison with those of the Cataclysmic ...

  12. Lyα EMITTERS IN HIERARCHICAL GALAXY FORMATION. II. ULTRAVIOLET CONTINUUM LUMINOSITY FUNCTION AND EQUIVALENT WIDTH DISTRIBUTION

    We present theoretical predictions of the UV continuum luminosity function (UV LF) and Lyα equivalent width (EW) distribution of Lyα emitters (LAEs) in the framework of the hierarchical clustering model of galaxy formation. The model parameters for the LAEs were determined by fitting to the observed Lyα LF at z = 5.7 in our previous study, and the fit indicates that extinction of Lyα photons by dust is significantly less effective than that of UV continuum photons, implying a clumpy dust distribution in the interstellar medium. We then compare the predictions about UV LFs and EW distributions with a variety of observations at z∼ 3-6, allowing no more free parameters and paying careful attention to the selection conditions of LAEs in each survey. We find that the predicted UV LFs and EW distributions are in nice agreement with observed data, and especially, our model naturally reproduces the existence of large EW LAEs (∼> 240 A) without introducing Pop III stars or top-heavy initial mass function. We show that both the stellar population (young age and low metallicity) and extinction by clumpy dust are the keys to reproducing large EW LAEs. The evidence of EW enhancement by clumpy dust is further strengthened by the quantitative agreement between our model and recent observations about a positive correlation between EW and extinction. The observed trend that brighter LAEs in the UV continuum tend to have smaller mean EW is also reproduced, and the clumpy dust plays an important role again for this trend. We suggested in our previous study that the transmission of the intergalactic medium for Lyα emission rapidly decreases from z ∼ 6 to 7 by fitting to Lyα LFs, and this evidence is quantitatively strengthened by the comparison with the UV LF and EW distribution at z ∼ 6.6.

  13. H$\\alpha$ kinematics of KPG 390

    Repetto, P; Fuentes-Carrera, R Gabbasov I

    2009-01-01

    In this work we present scanning Fabry-Perot H$\\alpha$ observations of the isolated interacting galaxy pair NGC 5278/79 obtained with the PUMA Fabry-Perot interferometer. We derived velocity fields, various kinematic parameters and rotation curves for both galaxies. Our kinematical results together with the fact that dust lanes have been detected in both galaxies, as well as the analysis of surface brightness profiles along the minor axis, allowed us to determine that both components of the interacting pair are trailing spirals.

  14. Discovery of a very cool object with extraordinarily strong H(alpha) emission

    Barrado y Navascus, D; Martn, E L; Bjar, V J S; Rebolo, R; Mundt, R; Navascues, David Barrado y; Osorio, Maria Rosa Zapatero; Martin, Eduardo L.; Bejar, Victor J.S.; Rebolo, Rafael; Mundt, Reinhard

    2002-01-01

    We report on the finding of the strongest H(alpha) emission -pseudoequivalent width of 705 Angstrom- known so far in a young, late type dwarf. This object, named as SOri71, is a substellar candidate member of the 1-8 Myr star cluster sigma Orionis. Due to its overluminous location in color-magnitude diagrams, SOri71 might be younger than other cluster members, or a binary of similar components. Its mass is in the range 0.021-0.012 M(sun), depending on evolutionary models and possible binarity. The broad H(alpha) line of SOri71 appears asymmetric, indicative of high velocity mass motions in the H(alpha) forming region. The origin of this emission is unclear at the present time. We discuss three possible scenarios: accretion from a disk, mass exchange between the components of a binary system, and emission from a chromosphere.

  15. Scattered H-alpha light from Galactic dust clouds

    Mattila, K. (Kimmo); Juvela, M.; K Lehtinen

    2006-01-01

    Bright emission nebulae, or HII regions, around hot stars are readily seen in H-alpha light. However, the all-pervasive faint H-alpha emission has only recently been detected and mapped over the whole sky. Mostly the H-alpha emission observed along a line of sight is produced by ionised gas in situ. There are, however, cases where all or most of the H-alpha radiation is due to scattering by electrons or dust particles which are illuminated by an H-alpha emitting source off the line of sight. ...

  16. The Appearance of Spicules in High Resolution Observations of Ca II H and H-alpha

    Pereira, Tiago M D; Carlsson, Mats

    2016-01-01

    Solar spicules are chromospheric fibrils that appear everywhere on the Sun, yet their origin is not understood. Using high resolution observations of spicules obtained with the Swedish 1-m Solar Telescope we aim to understand how spicules appear in filtergrams and Dopplergrams, how they compare in Ca II H and H-alpha, and what can make them appear and disappear. We find spicules display a rich and detailed spatial structure, and show a distribution of transverse velocities that when aligned with the line of sight can make them appear at different H-alpha wing positions. They become more abundant at positions closer to the line core, reflecting a distribution of Doppler shifts and widths. In H-alpha width maps they stand out as bright features both on disk and off-limb, reflecting their large Doppler motions and possibly higher temperatures than in the typical H-alpha formation region. Spicule lifetimes measured from narrowband images at only a few positions will be an underestimate because Doppler shifts can ...

  17. Equivalent width, shape and proper motion of the iron fluorescent line emission from the molecular clouds as an indicator of the illuminating source X-ray flux history

    Sunyaev, R.; Churazov, E.

    1998-01-01

    Observations of the diffuse emission in the 8--22 keV energy range, elongated parallel to the Galactic plane (Sunyaev et al. 1993) and detection of the strong 6.4 keV fluorescent line with $\\sim$ 1 keV equivalent width from some giant molecular clouds (e.g. Sgr B2) in the Galactic Centre region (Koyama 1994) suggest that the neutral matter of these clouds is (or was) illuminated by powerful X-ray radiation, which gave rise to the reprocessed radiation. The source of this radiation remains unk...

  18. Galactic Free-free and H-alpha Emission

    Smoot, George F.

    1998-01-01

    This document provides a brief summary estimate of Galactic free-free emission and H-alpha emission and their relationship. Particular emphasis is placed on estimating the potential free-free emission in the region of significant confusion for CMB anisotropy measurements. Existing x-ray, ultraviolet and H$\\alpha$ emission provide limits on the radio free-free emission and vice versa. These limits are generally somewhat smaller than the observed ``free-free'' (signal proportional to frequency^...

  19. The evolution of the equivalent width of the Ha emission line and specific star-formation rate in star-forming galaxies at 1

    Marmol-Queralto, E; Cullen, F; Dunlop, J S; Fontana, A; McLeod, D J

    2015-01-01

    We present the results of a study which uses spectral energy distribution (SED) fitting to investigate the evolution of the equivalent width (EW) of the Halpha emission line in star-forming galaxies over the redshift interval 1=1 in the CANDELS UDS and GOODS-S fields. Confining our analysis to a constant stellar mass range (9.5

  20. H-alpha observations of four novae in M31

    Jacoby, G.; Ciardullo, R.; Ford, H.

    1983-01-01

    On-line off-line H-alpha plates of M31's nucleus revealed four bright stellar objects (m sub R being approximately 14.9, 15.0, 15.8, 16.4) within 1.2 kpc of the galaxy center. Spectrophotometric observations made 10 days later showed the stars were novae in the stage of early decline. In the 10 day interval, the H-alpha emission from these novae faded less than a magnitude, despite the fact that their continua had long since faded from view. The high luminosity and long decay time of the H-alpha emission suggest it might make an excellent standard candle for extragalactic distance measurements.

  1. A Detection Of H-alpha In An Exoplanetary Exosphere

    Jensen, Adam G.; Redfield, Seth; Endl, Michael; Cochran, William D.; Koesterke, Lars; Barman, Travis S.

    2012-01-01

    We report on a search for H-alpha absorption in four exoplanets. Strong features at H-alpha are observed in the transmission spectra of both HD 189733b and HD 209458b. We attempt to characterize and remove the effects of stellar variability in HD 189733b, and along with an empirical Monte Carlo test the results imply a statistically significant transit-dependent feature of (-8.72+/-1.48)x10^-4 integrated over a 16 Angstrom band relative to the adjacent continuum. We interpret this as the firs...

  2. The All-sky Kinematics of Diffuse Galactic H-alpha Emission from WHAM

    Eagon, Andrew; Haffner, L. Matthew; Benjamin, Robert A.

    2016-01-01

    WHAM-SS (Wisconsin H-alpha Mapper Sky Survey) is the first all-sky velocity-resolved survey of the faint optical emisison line radiation from the diffuse ionized gas of the Milky Way Galaxy. With an angular resolution of one degree, velocity resolution of 12 km/s, and velocity range of 200 km/s, it allows for the study of the kinematics of the ionized gas across the Galaxy. We present first results on the all-sky velocity distribution of this gas. We show the results of Gaussian decomposition of line profiles as well as first and second moment maps both in the disk and at high latitude, and compare our results with some simple models for the density and velocity field of this gas. As in Haffner et al. (2003), we find that the high-latitude sky is characterized by a low velocity "infall" (toward the plane) in H-alpha, although there are also regions of outflow. We also present the variation in line widths as a function of direction and show how these widths correlate with different structures in the warm ionized medium. This program was supported by NSF Award AST-1108911 (for WHAM) and NSF Award AST-1004881 for the Wisconsin REU program in Astrophysics.

  3. H-alpha confirmation of novae in M31

    Ovcharov, E.; Nikolov, G.; Kostov, A.; Bozhilov, V.; Minev, M.; Valcheva, A.; Nedialkov, P.

    2015-08-01

    We report H-alpha and BR-band photometry of three objects in M31, suspected as novae. The objects are: PNV J00420640+4108211 = 2015-03a? (ATel# 7189), 2015-07c? (ATel# 7795, ATel #7818) and TCP J00401150+4042199 = 2015-07e? (ATel #7834).

  4. H-alpha features with hot onsets. I. Ellerman bombs

    Rutten, R J

    2016-01-01

    Ellerman bombs are transient brightenings of the wings of the Balmer lines that uniquely mark reconnection in the solar photosphere. They are also bright in strong Ca II and ultraviolet lines and in ultraviolet continua, but they are not visible in the optical continuum and the Na I D and Mg I b lines. These discordant visibilities invalidate all published Ellerman bomb modeling. I argue that the assumption of Saha-Boltzmann lower-level populations is informative to estimate bomb-onset opacities for these diverse diagnostics, even and especially for H-alpha, and employ such estimates to gauge the visibilities of Ellerman bomb onsets in all of them. They constrain Ellerman bomb formation to temperatures 10,000 - 20,000 K and hydrogen densities around 10^15 cm^-3. Similar arguments likely hold for H-alpha visibility in other transient phenomena with hot and dense onsets.

  5. Probing ISM Models with H-alpha observations

    Ferrara, Andrea

    1997-01-01

    I review the capabilities of H$\\alpha$ observations to constrain some aspects of the current models of the interstellar medium. In particular, it is shown that turbulence is a necessary ingredient of any viable model, since most of the energy produced by supernova explosions and ionizing radiation is stored in kinetic form in the ISM. Various forms of turbulent energy dissipation, including cloud collisions, are analyzed. Two additional aspects, concerning the existence of galactic fountains ...

  6. H{\\alpha} Imaging of Nearby Seyfert Host Galaxies

    Theios, R L; Ross, N R

    2016-01-01

    We used narrowband interference filters with the CCD imaging camera on the Nickel 1.0 meter telescope at Lick Observatory to observe 31 nearby (z < 0.03) Seyfert galaxies in the 12 {\\mu}m Active Galaxy Sample. We obtained pure emission line images of each galaxy in order to separate H{\\alpha} emission from the nucleus from that of the host galaxy. The extended H{\\alpha} emission is expected to be powered by newly formed hot stars, and correlates well with other indicators of current star formation in these galaxies: 7.7 {\\mu}m PAH, far-infrared, and radio luminosity. Relative to what would be expected from recent star formation, there is a 0.8 dex excess of radio emission in our Seyfert galaxies. The nuclear H{\\alpha} luminosity is dominated by the AGN, and is correlated with the hard X-ray luminosity. There is an upward offset of 1 dex in this correlation for the Seyfert 1s due to a strong contribution from the Broad Line Region. We found a correlation between star formation rate and AGN luminosity. In sp...

  7. Joint H-alpha and X-Ray Observations of Massive X-Ray Binaries. III. The Be X-ray Binaries HDE 245770 = A 0535+26 and X Persei

    Grundstrom, E D; Finch, C; Gies, D R; Huang, W; McSwain, M V; O'Brien, D P; Riddle, R L; Trippe, M L; Williams, S J; Wingert, D W; Zaballa, R A

    2007-01-01

    We present results from an H-alpha monitoring campaign of the Be X-ray binary systems HDE 245770 = A 0535+26 and X Per. We use the H-alpha equivalent widths together with adopted values of the Be star effective temperature, disk inclination, and disk outer boundary to determine the half-maximum emission radius of the disk as a function of time. The observations of HDE 245770 document the rapid spectral variability that apparently accompanied the regeneration of a new circumstellar disk. This disk grew rapidly during the years 1998 - 2000, but then slowed in growth in subsequent years. The outer disk radius is probably truncated by resonances between the disk gas and neutron star orbital periods. Two recent X-ray outbursts appear to coincide with the largest disk half-maximum emission radius attained over the last decade. Our observations of X Per indicate that its circumstellar disk has recently grown to near record proportions, and concurrently the system has dramatically increased in X-ray flux, presumably ...

  8. A DETECTION OF H{alpha} IN AN EXOPLANETARY EXOSPHERE

    Jensen, Adam G.; Redfield, Seth [Van Vleck Observatory, Astronomy Department, Wesleyan University, 96 Foss Hill Drive, Middletown, CT 06459 (United States); Endl, Michael; Cochran, William D.; Koesterke, Lars [Department of Astronomy, University of Texas, Austin, TX 78712 (United States); Barman, Travis, E-mail: Adam.Jensen@gmail.com, E-mail: sredfield@wesleyan.edu, E-mail: mike@astro.as.utexas.edu, E-mail: wdc@astro.as.utexas.edu, E-mail: lars@tacc.utexas.edu, E-mail: barman@lowell.edu [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States)

    2012-06-01

    We report on a search for H{alpha} absorption in four exoplanets. Strong features at H{alpha} are observed in the transmission spectra of both HD 189733b and HD 209458b. We attempt to characterize and remove the effects of stellar variability in HD 189733b, and along with an empirical Monte Carlo test the results imply a statistically significant transit-dependent feature of (- 8.72 {+-} 1.48) Multiplication-Sign 10{sup -4} integrated over a 16 A band relative to the adjacent continuum. We interpret this as the first detection of this line in an exoplanetary atmosphere. A previous detection of Ly{alpha} in HD 189733b's atmosphere allows us to calculate an excitation temperature for hydrogen, T{sub exc} = 2.6 Multiplication-Sign 10{sup 4} K. This calculation depends significantly on certain simplifying assumptions. We explore these assumptions and argue that T{sub exc} is very likely much greater than the radiative equilibrium temperature (the temperature the planet is assumed to be at based on stellar radiation and the planetary distance) of HD 189733b. A large T{sub exc} implies a very low density that is not in thermodynamic equilibrium with the planet's lower atmosphere. We argue that the n = 2 hydrogen required to cause H{alpha} absorption in the atmosphere is created as a result of the greater UV flux at HD 189733b, which has the smallest orbit and most chromospherically active central star in our sample. Though the overall integration of HD 209458b's transmission spectrum over a wide band is consistent with zero, it contains a dramatic, statistically significant feature in the transmission spectrum with reflectional symmetry. We discuss possible physical processes that could cause this feature. Our remaining two targets (HD 147506b and HD 149026b) do not show any clear features, so we place upper limits on their H{alpha} absorption levels.

  9. H-alpha response to geomagnetic disturbed activity at Arecibo.

    Santos, Pedrina; Kerr, R.; Noto, J.; Brum, Christiano; Gonzalez, Sixto

    Configured with a spectral resolution of 0.0086 nm at 6563A, the low resolution Fabry-Perot Interferometer (FPI) installed at Arecibo Observatory sampled the geocoronal Balmer-alpha emission for sixty nights during new moon periods from September 2006 to September 2007. In this work two of these periods are analyzed according to the variability with the geomagnetic activity. With this purpose, the effect of the shadow height, local time and solar flux depen-dencies were found and isolated and only the possible variations due the geomagnetic activity were evaluated. The residuos of the relative H-alpha intensity and temperature are analyzed.

  10. H-alpha scans of high-velocity clouds

    No H-alpha emission has been found in a large-aperture Fabry-Perot spectrometer search for spectra toward six high-velocity clouds, down to detection limits of 0.2-0.6 R. The clouds seem to be located in a medium of low density, or high temperature, or both. The data obtained imply an ambient flux of ionizing radiation of less than 0.5-1.3 million photons/sq cm per sec at the clouds; this is less than the estimate of Bregman and Harrington (1986) for the Galactic halo. 30 references

  11. Galactic H $\\alpha$ emission and the Cosmic Microwave Background

    Marcelin, M; Bartlett, J G; Valls-Gabaud, D; Blanchard, A

    1998-01-01

    We present observations of Galactic H alpha emission along two declination bands where the South Pole cosmic microwave background experiment reports temperature fluctuations. The high spectral resolution of our Fabry-Perot system allows us to separate the Galactic signal from the much larger local sources of H alpha emission, such as the Earth's geocorona. For the two bands (at declination -62 and -63 degrees), we find a total mean emission of about 1 Rayleigh with variations of about 0.3 R. The variations are within the estimated uncertainty of our total intensity determinations. For an ionized gas at T around 10**4 K, this corresponds to a maximum free-free brightness temperature of less than 10 microK at 30 GHz (K-band). Thus, unless there is a hot gas component with T around 10**6 K, our results imply that there is essentially no free-free contamination of the SP91 (Schuster et al. 1993) and SP94 (Gunderson et al.1995) data sets.

  12. Modeling of hot Jupiter H alpha transmission spectral line

    Huang, Chenliang; Arras, Phil; Christie, Duncan

    2016-01-01

    The upper atmosphere of hot Jupiters is subject to the strong stellar radiation field of the host star, which can heat and ionize the gas, as well as excite atoms to higher energy levels. For planets near the parent star, a thick layer of atomic hydrogen may be present, which has now been observed through both Lyman alpha and H alpha absorption of starlight during transit. Motivated by these observations, we revisit the calculations of Christie et al to study the hydrogen level populations in detail, including radiative (de-)excitation, collisional (de-)excitation, collisional ell-mixing processes up to n = 6 states, as well as radiative ionization, recombination and collisional ionization processes. Using theHD 189733b thermal and photoionization equilibrium hydrostatic balance atmosphere model of Christie et al, we find that the 2s state population is dominated by a) creation and destruction channels via np states (n > 2), which was not considered previously, and b) 2s to 2p collisional ?-mixing process, which was treated incorrectly. I will show our modeling of H alpha transit depth observation with new level populations module.

  13. Automatic Selection of H-alpha Emission-Line Galaxies

    Lasheras, Oscar Alonso

    1996-06-01

    We have developed a procedure for the automatic selection of emission-line galaxies candidates from the digitization of objective prism plates. This procedure has been applied over two pair of direct and prism plates of the Universidad Complutense de Madrid (UCM) survey, digitized by the fast and high performance microdensitometer MAMA (Machine Automatique a Mesurer pour l'Astronomie) located at the Observatoire de Paris. The plates where obtained with the Schmidt Telescope at Calar Alto Observatory in Almeria (Spain). The instrumental setup used for the acquisition of the prism plates (IIIa-F emulsion and RG630 filter) allows to register the H-alpha +[NII] emission for galaxies up to z <= 0.045. Therefore the criteria developed for the automatic selection of ELGs candidates consist in identifying the H-alpha emission feature in the extracted monodimensional prism spectra. We have noted that there is not a nitid edge to distinguish between the spectra showing the H-alpha line in emission and the rest. Consequently we have studied the residual obtained after the estimation of the continuum and the variation of the slopes calculated over each spectrum in order to identify the line feature. The efficiency of this technique has been tested by comparing the results obtained applying the automatic procedure with those achieved after a careful visual search for the candidates, as performed up to date in the UCM and similar surveys. The results show us that the automatic procedure only ignore very extended and near saturated known galaxies with well resolved emitting regions located at the external regions. Spectroscopic observations of moderate dispersion for the whole set of candidates selected both automatic and visually show that the former has been able, not only to select the 100% of candidates with confirmed emission recognized also by visual means, but also, and what is more important, to identify a 29% more of confirmed ELGs, without lost of efficiency by the increase of spurious identifications. The digitization of the plates has allowed us to measure a set of accurate observational parameters as positions, magnitudes, sizes and redshifts that will permit to perform statistical analysis of this kind of objects before carrying out specific observations with larger telescopes. Since our plates have not sensitometric spots to calculate its characteristic curve, it has been necessary to obtain external calibrations by comparing with calibrated data offered by several catalogs. We have tested that the precision achieved using this method is mainly limited by the accuracy of the different catalog employed. The redshift of the candidates can be derived from the location of the H-alpha line on the prism spectra. Since they have no spectral features to refer the position of the H$\\alpha$ line, the positions of the objects in the direct plate and their transformations to the prism one have been used to provide a reference point which is dependent neither on magnitude, nor on color, nor spatial light distribution. A precision of 0.003 is reached when measuring redshifts by this method. Finally, the comparison of the candidate samples obtained from two plates of our survey covering the same area on the sky allows the study of the selection effects that affects the identification of the H-alpha line in photographic prism plates. The parameter EW X F of the emission H-alpha +[NII] can be used as a threshold that inform us about the unambiguous identification of the emission in the prism spectra, being 10^-13 erg s^-1 cm^-2A the mean value of this parameter for the whole sample of the UCM survey. We have also developed an algorithm to simulate the expected objective-prism spectra for an object by using different instrumental setups. The simulation permits to investigate the different combinations of EW, fluxes and magnitude that allow the detection of the H$\\alpha$ line in the plates and will be used in the near future to predict the expected spectra by the substitution of the photographic emulsion with CCD detectors. (SECTION: Dissertation Summaries)

  14. A Detection Of H-alpha In An Exoplanetary Exosphere

    Jensen, Adam G; Endl, Michael; Cochran, William D; Koesterke, Lars; Barman, Travis S

    2012-01-01

    We report on a search for H-alpha absorption in four exoplanets. Strong features at H-alpha are observed in the transmission spectra of both HD 189733b and HD 209458b. We attempt to characterize and remove the effects of stellar variability in HD 189733b, and along with an empirical Monte Carlo test the results imply a statistically significant transit-dependent feature of (-8.72+/-1.48)x10^-4 integrated over a 16 Angstrom band relative to the adjacent continuum. We interpret this as the first detection of this line in an exoplanetary atmosphere. A previous detection of Ly-alpha in HD 189733b's atmosphere allows us to calculate an excitation temperature for hydrogen, T_exc=2.6x10^4 K. This calculation depends significantly on certain simplifying assumptions. We explore these assumptions and argue that T_exc is very likely much greater than the radiative equilibrium temperature (the temperature the planet is assumed to be at based on stellar radiation and the planetary distance) of HD 189733b. A large T_exc im...

  15. The interacting galaxy pair KPG 390: H$\\alpha$ kinematics

    Repetto, P; Gabbasov, R; Fuentes-Carrera, I

    2010-01-01

    In this work we present scanning Fabry-Perot H$\\alpha$ observations of the isolated interacting galaxy pair NGC 5278/79 obtained with the PUMA Fabry-Perot interferometer. We derived velocity fields and rotation curves for both galaxies. For NGC 5278 we also obtained the residual velocity map to investigate the non-circular motions, and estimated its mass by fitting the rotation curve with a disk+halo components. We test three different types of halo (pseudo-isothermal, Hernquist and Navarro Frenk White) and obtain satisfactory fits to the rotation curve for all profiles. The amount of dark matter required by pseudo-isothermal profile is about ten times smaller than, that for the other two halo distributions. Finally, our kinematical results together with the analysis of dust lanes distribution and of surface brightness profiles along the minor axis allowed us to determine univocally that both components of the interacting pair are trailing spirals.

  16. Flare asymmetry as seen in offband H-alpha filtergrams

    Tang, F.

    1983-01-01

    Narrow-band H-alpha filtergrams at + or - 1 A and + or - 2 A from the line center were used to study the asymmetry of flares. Of the 60 flares studied, 92% show red asymmetry while 5% show blue asymmetry. Typically, the filtergrams show a striking dominance of the red wing over the blue wing from onset until late in the decay phase. The difference in intensity of the flare emissions is further augmented by the extensiveness of the emission area in the brighter wing. New kernel-like emissions were often found many minutes after the flare maximum. Spatially, they are displaced from the previous kernels. The late emissions show the same asymmetry as that of the earlier part of the flare.

  17. The H-alpha light curves of novae in M31

    Ciardullo, Robin; Shafter, Allen W.; Ford, Holland C.; Neill, James D.; Shara, Michael M.

    1990-01-01

    H-alpha and B light curves are presented for 11 M31 novae, four of which were well observed near maximum. These data, along with the H-alpha light curves of two Galactic novae, demonstrate that a nova's maximum H-alpha flux occurs days or weeks after its continuum maximum at a monochromatic intensity 1-2 magnitudes above its peak flux in B. Moreover, after this maximum is achieved, a typical nova will radiate a third as many photons in H-alpha as in the entire B bandpass. The most interesting part of a nova's H-alpha light curve, however, is its decline. It is found that, regardless of a nova's speed, its H-alpha decay rate after maximum is almost identical to its decay rate in B. This behavior suggests that most of a nova's optical luminosity during early decline is continuum emission from the nebula, rather than direct radiation from the central source.

  18. High spatial resolution optical imaging of the multiple T Tauri system LkH{\\alpha} 262/LkH{\\alpha} 263

    Velasco, S; Oscoz, A; Mackay, C; Labadie, L; Garrido, A Pérez; Crass, J; Díaz-Sánchez, A; Femenía, B; González-Escalera, V; King, D L; López, R L; Puga, M; Rodríguez-Ramos, L F; Zuther, J

    2016-01-01

    We report high spatial resolution i' band imaging of the multiple T Tauri system LkH$\\alpha$ 262/LkH$\\alpha$ 263 obtained during the first commissioning period of the Adaptive Optics Lucky Imager (AOLI) at the 4.2 m William Herschel Telescope, using its Lucky Imaging mode. AOLI images have provided photometry for each of the two components LkH$\\alpha$ 263 A and B (0.41 arcsec separation) and marginal evidence for an unresolved binary or a disc in LkH$\\alpha$ 262. The AOLI data combined with previously available and newly obtained optical and infrared imaging show that the three components of LkH$\\alpha$ 263 are co-moving, that there is orbital motion in the AB pair, and, remarkably, that LkH$\\alpha$ 262-263 is a common proper motion system with less than 1 mas/yr relative motion. We argue that this is a likely five-component gravitationally bounded system. According to BT-settl models the mass of each of the five components is close to 0.4 M$_{\\odot}$ and the age is in the range 1-2 Myr. The presence of discs...

  19. Two views of the Andromeda Galaxy H-alpha and far infrared

    Devereux, N. A.; Price, R.; Wells, L. A.; Duric, N.

    1994-11-01

    A complete H-alpha image of the Andromeda Galaxy (M31) is presented allowing the first direct measurement of the total H-alpha luminosity which is (7.3 +/- 2.4) x 106 solar luminosity. The H-alpha emission is associated with three morphologically distinct components; a large scale star-forming ring, approximately 1.65 deg in diameter, contributing 66% of the total H-alpha emission, a bright nucleus contributing 6% of the total H-alpha emission with the remaining 28% contributed by a previously unidentified component of extended and filamentary H-alpha emission interior to the star forming ring. The correspondence between the H-alpha image and the Infrared Astronomy Satellite (IRAS) far-infrared high resolution image is striking when both are convolved to a common resolution of 105 arcsec. The close correspondence between the far-infrared and H-alpha images suggests a common origin for the two emissions. The star-forming ring contributes 70% of the far-infrared luminosity of M31. Evidence that the ring emission is energized by high mass stars includes the fact that peaks in the far-infrared emission coincide identically with H II regions in the H-alpha image. In addition, the far-infrared to H-alpha luminosity ratio within the star-forming ring is similar to what one would expect for H II regions powered by stars of spectral types ranging between O9 and B0. The origin of the filamentary H-alpha and far-infrared luminosity interior to the star-forming ring is less clear, but it is almost certainly not produced by high mass stars.

  20. A catalogue of integrated H\\alpha\\ fluxes for ~1100 Galactic planetary nebulae

    Bojicic, I S; Parker, Q A

    2011-01-01

    We present new determinations of the integrated H\\alpha\\ flux for ~1100 Galactic planetary nebulae measured from the Southern H-Alpha Sky Survey Atlas (SHASSA) and its northern counterpart, the Virginia Tech Spectral-Line Survey (VTSS). This catalogue is the largest homogeneous database of its kind, tripling the number of currently available measurements.

  1. The Wisconsin H-Alpha Mapper Sky Survey

    Haffner, L. Matthew; Reynolds, Ronald J.; Babler, Brian L.; Madsen, Gregory J.; Hill, Alex S.; Barger, Kathleen; Jaehnig, Kurt P.; Mierkiewicz, Edwin J.; Percival, Jeffrey W.; Chopra, Nitish; Pingel, Nickolas; Reese, Daniel T.; Gostisha, Martin; Wunderlin, Jennifer

    2016-01-01

    We present the first all-sky, kinematic survey of Hα from the Milky Way, combining survey observations taken with the Wisconsin H-Alpha Mapper (WHAM) from Kitt Peak (1997-2007) and Cerro Tololo (2009-present). The WHAM Sky Survey (WHAM-SS) reaches sensitivity levels of about 0.1 R (EM ~ 0.2 pc cm^-6) with emission detected toward every direction in the sky. Each pointing of the survey comprises a spatially integrated spectrum from a one-degree beam on the sky covering at least 200 km/s around the Local Standard of Rest with 12 km/s spectral resolution. WHAM was designed primarily to study the pervasive warm ionized medium (WIM) component of the interstellar medium (ISM) but also reveals many large-scale, locally-ionized regions throughout the Galaxy. The WIM is a diffuse but thick component of the ISM that extends several kiloparsecs into the Galactic halo with a kinematic signature that traces the gaseous spiral arms of the Galaxy. In addition to this fairly smooth global emission, the Hα sky contains many individual H II regions and supernova remnants, a few revealed in the WHAM-SS for the first time. Some locations are dominated by complex filamentary network of diffuse ionized gas where the ISM has been shaped by past winds and supernovae and is now powered by a new wave of star formation. At high latitudes, faint emission from intermediate-velocity clouds is also regularly present. The success of WHAM as a fully remote observing facility for nearly two decades is due in no small part to the excellent and responsive support staff at KPNO in Arizona and CTIO in Chile. WHAM has been designed, built, and operated primarily through support of the National Science Foundation. The current research presented here is funded by award AST-1108911.

  2. Dust Attenuation and H(alpha) Star Formation Rates of Z Approx. 0.5 Galaxies

    Ly, Chun; Malkan, Matthew A.; Kashikawa, Nobunari; Ota, Kazuaki; Shimasaku, Kazuhiro; Iye, Masanori; Currie, Thayne

    2012-01-01

    Using deep narrow-band and broad-band imaging, we identify 401 z approximately 0.40 and 249 z approximately 0.49 H-alpha line-emitting galaxies in the Subaru Deep Field. Compared to other H-alpha surveys at similar redshifts, our samples are unique since they probe lower H-alpha luminosities, are augmented with multi-wavelength (rest-frame 1000AA--1.5 microns) coverage, and a large fraction (20%) of our samples has already been spectroscopically confirmed. Our spectra allow us to measure the Balmer decrement for nearly 60 galaxies with H-beta detected above 5-sigma. The Balmer decrements indicate an average extinction of A(H-alpha)=0.7(uparrow){+1.4}_{-0.7} mag. We find that the Balmer decrement systematically increases with higher H-alpha luminosities and with larger stellar masses, in agreement with previous studies with sparser samples. We find that the SFRs estimated from modeling the spectral energy distribution (SED) is reliable---we derived an "intrinsic" H-alpha luminosity which is then reddened assuming the color excess from SED modeling. The SED-predicted H-alpha luminosity agrees with H-alpha narrow-band measurements over 3 dex (rms of 0.25 dex). We then use the SED SFRs to test different statistically-based dust corrections for H-alpha and find that adopting one magnitude of extinction is inappropriate: galaxies with lower luminosities are less reddened. We find that the luminosity-dependent dust correction of Hopkins et al. yields consistent results over 3 dex (rms of 0.3 dex). Our comparisons are only possible by assuming that stellar reddening is roughly half of nebular reddening. The strong correspondence argue that with SED modeling, we can derive reliable intrinsic SFRs even in the absence of H-alpha measurements at z approximately 0.5.

  3. Width issues

    Current practices at British Columbia Hydro establish right-of-way widths on the basis of Canadian Standards Association (CSA) standards and BC Hydro standards and practices. The CSA sets certain minimum requirements which are increased by BC Hydro engineers to suit local conditions and design or maintenance requirements. As part of a general review of the utility's rights-of-way policies, a task team was established to consider the following issues related to right-of-way width: CSA and BC Hydro standards and practices; future use of rights-of-way by BC Hydro; electromagnetic interference; audible noise; public safety; right-of-way width for underground circuits; incorporation of setbacks in municipal bylaws; legislative approaches; and land use and development. Recommendations for continuation or modification of current practices are made in each of the issue areas. Justifications are provided for the recommendations, along with costs of implementation and alternative options

  4. The H-alpha Luminosity Function and Star-Formation Rate Volume Density at z=0.8 from the NEWFIRM H-alpha Survey

    Ly, Chun; Dale, Daniel A; Momcheva, Ivelina; Salim, Samir; Staudaher, Shawn; Moore, Carolynn A; Finn, Rose

    2010-01-01

    [Abridged] We present new measurements of the H-alpha luminosity function (LF) and SFR volume density for galaxies at z~0.8. Our analysis is based on 1.18$\\mu$m narrowband data from the NEWFIRM H-alpha Survey, a comprehensive program designed to capture deep samples of intermediate redshift emission-line galaxies using narrowband imaging in the near-infrared. The combination of depth ($\\approx1.9\\times10^{-17}$ erg s$^{-1}$ cm$^{-2}$ in H-alpha at 3$\\sigma$) and areal coverage (0.82 deg$^2$) complements other recent H-alpha studies at similar redshifts, and enables us to minimize the impact of cosmic variance and place robust constraints on the shape of the LF. The present sample contains 818 NB118 excess objects, 394 of which are selected as H-alpha emitters. Optical spectroscopy has been obtained for 62% of the NB118 excess objects. Empirical optical broadband color classification is used to sort the remainder of the sample. A comparison of the LFs constructed for the four individual fields reveals signific...

  5. Observatons of NGC 3077 Galaxy in Narrow Band [SII] and H_alpha Filters

    Andjelic, M; Arbutina, B; Ilic, D; Urosevic, D

    2011-01-01

    We present observations of the HI tidal arm near dwarf galaxy NGC 3077 (member of the M81 galaxy group) in narrow band [SII] and H_alpha filters. Observations were carried out in March 2011 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for possible supernova remnant candidates (identified as sources with enhanced [SII] emission relative to their H_alpha emission) in this region yielded no sources of this kind. Nevertheless, we found a number of objects with significant H_alpha emission that probably represent uncatalogued, low brightness HII regions.

  6. A Correlation between Balmer H-alpha Emission and Infrared Cirrus

    McCullough, Peter R.

    1997-01-01

    A 13x13 degree image of Balmer H-alpha emission at galactic latitude -65 degrees is presented. Sensitivity is limited in part by confusion: the peak-to-valley anisotropy of the H-alpha surface brightness is 0.2 Rayleighs on angular scales of 0.1 to 1.0 degrees. The morphology of the H-alpha emission is similar to that of the 100 um emission previously observed by the Infrared Astronomical Satellite (IRAS). A point-by-point comparison of the two shows a marginally detected (3-sigma) positive c...

  7. Extracting H$\\alpha$ flux from photometric data in the J-PLUS survey

    Vilella-Rojo, G; López-Sanjuan, C; Cenarro, A J; Varela, J; Díaz-García, L A; Cristóbal-Hornillos, D; Ederoclite, A; Marín-Franch, A; Moles, M

    2015-01-01

    We present the main steps that will be taken to extract H$\\alpha$ emission flux from Javalambre Photometric Local Universe Survey (J-PLUS) photometric data. For galaxies with $z\\lesssim0.015$, the H$\\alpha$+[NII] emission is covered by the J-PLUS narrow-band filter $F660$. We explore three different methods to extract the H$\\alpha$ + [NII] flux from J-PLUS photometric data: a combination of a broad-band and a narrow-band filter ($r'$ and $F660$), two broad-band and a narrow-band one ($r'$, $i'$ and $F660$), and a SED-fitting based method using 8 photometric points. To test these methodologies, we simulated J-PLUS data from a sample of 7511 SDSS spectra with measured H$\\alpha$ flux. Based on the same sample, we derive two empirical relations to correct the derived H$\\alpha$+[NII] flux from dust extinction and [NII] contamination. We find that the only unbiased method is the SED fitting based one. The combination of two filters underestimates the measurements of the H$\\alpha$ + [NII] flux by a 28%, while the th...

  8. A Correlation between Balmer H-$\\alpha$ Emission and Infrared Cirrus

    McCullough, P R

    1997-01-01

    A 13x13 degree image of Balmer H-alpha emission at galactic latitude -65 degrees is presented. Sensitivity is limited in part by confusion: the peak-to-valley anisotropy of the H-alpha surface brightness is 0.2 Rayleighs on angular scales of 0.1 to 1.0 degrees. The morphology of the H-alpha emission is similar to that of the 100 um emission previously observed by the Infrared Astronomical Satellite (IRAS). A point-by-point comparison of the two shows a marginally detected (3-sigma) positive correlation, rho = +0.14 (+-0.04). The slope of the correlated components of the 100 um and H-alpha emissions is 1.26 (+0.45) (-0.32) MJy/sr/R. Using parameters from the literature, we predict that emission from dust and ionized gas at high latitudes produces 3 times more H-alpha emission per unit 100 um emission than does backscattering of H-alpha emission from Galactic H II regions by dust at high latitude. Observations of this type may allow us to distinguish between Galactic foreground and cosmic background for both th...

  9. NEBULAR ATTENUATION IN H{alpha}-SELECTED STAR-FORMING GALAXIES AT z = 0.8 FROM THE NewH{alpha} SURVEY

    Momcheva, Ivelina G. [Astronomy Department, Yale University, New Haven, CT 06511 (United States); Lee, Janice C.; Ouchi, Masami [Carnegie Observatories, Pasadena, CA 91101 (United States); Ly, Chun [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Salim, Samir [Astronomy Department, Indiana University, Bloomington, IN 47405 (United States); Dale, Daniel A. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Finn, Rose [Physics Department, Siena College, Loudonville, NY 12211 (United States); Ono, Yoshiaki, E-mail: ivelina.momcheva@yale.edu [Department of Astronomy, Graduate School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2013-02-01

    We present measurements of the dust attenuation of H{alpha}-selected emission-line galaxies at z = 0.8 from the NewH{alpha} narrowband survey. The analysis is based on deep follow-up spectroscopy with Magellan/IMACS, which captures the strong rest-frame optical emission lines from [O II] {lambda}3727 to [O III] {lambda}5007. The spectroscopic sample used in this analysis consists of 341 confirmed H{alpha} emitters. We place constraints on the active galactic nucleus (AGN) fraction using diagnostics that can be applied at intermediate redshift. We find that at least 5% of the objects in our spectroscopic sample can be classified as AGNs and 2% are composite, i.e., powered by a combination of star formation and AGN activity. We measure the dust attenuation for individual objects from the ratios of the higher order Balmer lines. The H{beta} and H{gamma} pair of lines is detected with S/N > 5 in 55 individual objects and the H{beta} and H{delta} pair is detected in 50 individual objects. We also create stacked spectra to probe the attenuation in objects without individual detections. The median attenuation at H{alpha} based on the objects with individually detected lines is A(H{alpha}) = 0.9 {+-} 1.0 mag, in good agreement with the attenuation found in local samples of star-forming galaxies. We find that the z = 0.8 galaxies occupy a similar locus of attenuation as a function of magnitude, mass, and star formation rate (SFR) as a comparison sample drawn from the SDSS DR4. Both the results from the individual z = 0.8 galaxies and from the stacked spectra show consistency with the mass-attenuation and SFR-attenuation relations found in the local universe, indicating that these relations are also applicable at intermediate redshift.

  10. A Deeper Look at Faint H$\\alpha$ Emission in Nearby Dwarf Galaxies

    Lee, Janice C; McDonald, Michael; Hilbert, Bryan

    2016-01-01

    We present deep H$\\alpha$ imaging of three nearby dwarf galaxies, carefully selected to optimize observations with the Maryland-Magellan Tunable Filter (MMTF) on the Magellan 6.5m telescope. An effective bandpass of $\\sim$13\\AA\\ is used, and the images reach 3$\\sigma$ flux limits of $\\sim$8$\\times10^{-18}$ ergs s$^{-1}$ cm$^{-2}$, which is about an order of magnitude lower than standard narrowband observations obtained by the most recent generation of local H$\\alpha$ galaxy surveys. The observations were originally motivated by the finding that the H$\\alpha$/FUV flux ratio of galaxies systematically declines as global galactic properties such as the star formation rate and stellar mass decrease. The three dwarf galaxies selected for study have star formation rates, that when calculated from their H$\\alpha$ luminosities using standard conversion recipes, are $\\sim$50\\% of those based on the FUV. Follow-up studies of many of the potential causes for the trends in the H$\\alpha$/FUV flux ratio have been performed...

  11. Supernova-Driven Outflows in NGC 7552: A Comparison of H-alpha and UV Tracers

    Wood, Corey M; Calzetti, Daniela; Leitherer, Claus; Chisholm, John; Gallagher, John S

    2015-01-01

    We investigate the supernova-driven galactic wind of the barred spiral galaxy NGC 7552, using both ground-based optical nebular emission lines and far-ultraviolet absorption lines measured with the Hubble Space Telescope Cosmic Origins Spectrograph. We detect broad (~300 km/s) blueshifted (-40 km/s) optical emission lines associated with the galaxy's kpc-scale star-forming ring. The broad line kinematics and diagnostic line ratios suggest that the H-alpha emission comes from clouds of high density gas entrained in a turbulent outflow. We compare the H-alpha emission line profile to the UV absorption line profile measured along a coincident sight line and find significant differences. The maximum blueshift of the H-alpha-emitting gas is ~290 km/s, whereas the UV line profile extends to blueshifts upwards of 1000 km/s. The mass outflow rate estimated from the UV is roughly nine times greater than that estimated from H-alpha. We argue that the H-alpha emission traces a cluster-scale outflow of dense, low velocit...

  12. A Dual Narrowband Survey for H\\alpha\\ Emitters at z=2.2: Demonstration of the Technique and Constraints on the H\\alpha\\ Luminosity Function

    Lee, Janice C; Spitler, L; Labbe, I; Salim, S; Persson, S E; Ouchi, M; Dale, D; Monson, A; Murphy, D

    2012-01-01

    We present first results from a narrowband imaging program for intermediate redshift emission-line galaxies using the newly commissioned FourStar infrared camera at the 6.5m Magellan telescope. To enable prompt identification of H\\alpha\\ emitters, a pair of custom 1% filters, which sample low-airglow atmospheric windows at 1.19 \\mu m and 2.10 \\mu m, is used to detect both H\\alpha\\ and [OII]\\lambda 3727 emission from the same redshift volume at z=2.2. Initial observations are taken over a 130 arcmin^2 area in the CANDELS-COSMOS field. The exquisite image quality resulting from the combination of the instrument, telescope, and standard site conditions (~0.55" FWHM) allows the 1.19 \\mu m and 2.10 \\mu m data to probe 3\\sigma\\ emission-line depths down to 1.0e-17 erg/s/cm^2 and 1.2e-17 erg/s/cm^2 respectively, in less than 10 hours of integration time in each narrowband. For H\\alpha\\ at z=0.8 and z=2.2, these fluxes correspond to observed star formation rates of ~0.3 and ~4 Msun/yr respectively. We find 122 source...

  13. H-alpha Imaging Survey of Low-Redshift Cluster Dwarf Galaxies

    Barkhouse, Wayne; Kalawila, Sandanuwan; Rude, Cody; Sultanova, Madina; Archer, Haylee Nichole; Foote, Gregory

    2016-01-01

    We describe our on-going H-alpha imaging survey to measure the star formation activity of dwarf galaxies selected from a sample of low-redshift (0.02 environment can be quantified using radial-dependent measures of the star formation rate within individual clusters, and by comparing clusters within our sample on a cluster-to-cluster basis. Comparison of our H-alpha measurements to CFHT u-band imaging data of our cluster sample, permits us to explore the correlation between the UV continuum and H-alpha emission of the dwarf galaxy population. The goal of our survey is to further understand the mechanism that is responsible for the enhancement/quenching of star formation as dwarf galaxies fall into the galaxy cluster environment.

  14. Predicting the Redshift 2 H-Alpha Luminosity Function Using [OIII] Emission Line Galaxies

    Mehta, Vihang; Scarlata, Claudia; Colbert, James W.; Dai, Y. S.; Dressler, Alan; Henry, Alaina; Malkan, Matt; Rafelski, Marc; Siana, Brian; Teplitz, Harry I.; Bagley, Micaela; Beck, Melanie; Ross, Nathaniel R.; Rutkowski, Michael; Wang, Yun

    2015-01-01

    Upcoming space-based surveys such as Euclid and WFIRST-AFTA plan to measure Baryonic Acoustic Oscillations (BAOs) in order to study dark energy. These surveys will use IR slitless grism spectroscopy to measure redshifts of a large number of galaxies over a significant redshift range. In this paper, we use the WFC3 Infrared Spectroscopic Parallel Survey (WISP) to estimate the expected number of H-alpha emitters observable by these future surveys. WISP is an ongoing Hubble Space Telescope slitless spectroscopic survey, covering the 0.8 - 1.65 micrometers wavelength range and allowing the detection of H-alpha emitters up to z approximately equal to 1.5 and [OIII] emitters to z approximately equal to 2.3. We derive the H-alpha-[OIII] bivariate line luminosity function for WISP galaxies at z approximately equal to 1 using a maximum likelihood estimator that properly accounts for uncertainties in line luminosity measurement, and demonstrate how it can be used to derive the H-alpha luminosity function from exclusively fitting [OIII] data. Using the z approximately equal to 2 [OIII] line luminosity function, and assuming that the relation between H-alpha and [OIII] luminosity does not change significantly over the redshift range, we predict the H-alpha number counts at z approximately equal to 2 - the upper end of the redshift range of interest for the future surveys. For the redshift range 0.7 less than z less than 2, we expect approximately 3000 galaxies per sq deg for a flux limit of 3 x 10(exp -16) ergs per sec per sq cm (the proposed depth of Euclid galaxy redshift survey) and approximately 20,000 galaxies per sq deg for a flux limit of approximately 10(exp -16) ergs per sec per sq cm (the baseline depth of WFIRST galaxy redshift survey).

  15. Observational and theoretical constraints for an H$\\alpha$-halo around the Crab Nebula

    Tziamtzis, A.; Schirmer, M.; Lundqvist, P.; Sollerman, J.

    2009-01-01

    We searched for a fast moving H$\\alpha$ shell around the Crab nebula. Such a shell could account for this supernova remnant's missing mass, and carry enough kinetic energy to make SN 1054 a normal Type II event. Deep H$\\alpha$ images were obtained with WFI at the 2.2m MPG/ESO telescope and with MOSCA at the 2.56m NOT. The data are compared with theoretical expectations derived from shell models with ballistic gas motion, constant temperature, constant degree of ionisation and a power law for ...

  16. H-alpha Survey of the Local Volume: Isolated Southern Galaxies

    Kaisin, S S; Knyazev, A Yu; Karachentsev, I D

    2007-01-01

    We present our H-alpha observations of 11 isolated southern galaxies: SDIG, PGC 51659, E 222-010, E 272-025, E 137-018, IC 4662, Sag DIG, IC 5052, IC 5152, UGCA 438, and E149-003, with distances from 1 to 7 Mpc. We have determined the total H-alpha fluxes from these galaxies. The star formation rates in these galaxies range from 10^{-1} (IC 4662) to 10^{-4}_{\\odot}/yr (SDIG) and the gas depletion time at the observed star formation rates lies within the range from 1/6 to 24 Hubble times H_0^{-1} .

  17. Evidence for ubiquitous high-equivalent-width nebular emission in z ∼ 7 galaxies: toward a clean measurement of the specific star-formation rate using a sample of bright, magnified galaxies

    Growing observational evidence indicates that nebular line emission has a significant impact on the rest-frame optical fluxes of z ∼ 5-7 galaxies. This line emission makes z ∼ 5-7 galaxies appear more massive, with lower specific star-formation rates (sSFRs). However, corrections for this line emission have been difficult to perform reliably because of huge uncertainties on the strength of such emission at z ≳ 5.5. In this paper, we present the most direct observational evidence thus far for ubiquitous high-equivalent-width (EW) [O III] + Hβ line emission in Lyman-break galaxies at z ∼ 7, and we present a strategy for an improved measurement of the sSFR at z ∼ 7. We accomplish this through the selection of bright galaxies in the narrow redshift window z ∼ 6.6-7.0 where the Spitzer/Infrared Array Camera (IRAC) 4.5 μm flux provides a clean measurement of the stellar continuum light, in contrast with the 3.6 μm flux, which is contaminated by the prominent [O III] + Hβ lines. To ensure a high signal-to-noise ratio for our IRAC flux measurements, we consider only the brightest (H 160 < 26 mag) magnified galaxies we have identified behind galaxy clusters. It is remarkable that the mean rest-frame optical color for our bright seven-source sample is very blue, [3.6]-[4.5] = –0.9 ± 0.3. Such blue colors cannot be explained by the stellar continuum light and require that the rest-frame EW of [O III] + Hβ is greater than 637 Å for the average source. The four bluest sources from our seven-source sample require an even more extreme EW of 1582 Å. We can also set a robust lower limit of ≳ 4 Gyr–1 on the sSFR of our sample based on the mean spectral energy distribution.

  18. Evidence for ubiquitous high-equivalent-width nebular emission in z ∼ 7 galaxies: toward a clean measurement of the specific star-formation rate using a sample of bright, magnified galaxies

    Smit, R.; Bouwens, R. J.; Labbé, I. [Leiden Observatory, Leiden University, NL-2300 RA Leiden (Netherlands); Zheng, W.; Lemze, D.; Ford, H. [Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Bradley, L.; Coe, D.; Postman, M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21208 (United States); Donahue, M. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Moustakas, J. [Siena College, 515 Loudon Road, Loudonville, NY 12211 (United States); Umetsu, K. [Institute of Astronomy and Astrophysics, Academia Sinica, P. O. Box 23-141, Taipei 10617, Taiwan (China); Zitrin, A.; Bartelmann, M. [Institut fur Theoretische Astrophysik, ZAH, Albert-Ueberle-Straß e 2, 69120 Heidelberg (Germany); Gonzalez, V. [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Benítez, N.; Jimenez-Teja, Y. [Instituto de Astrofisica de Andalucia (CSIC), C/Camino Bajo de Huetor 24, Granada 18008 (Spain); Broadhurst, T. [Department of Theoretical Physics, University of the Basque Country, P. O. Box 644, 48080 Bilbao (Spain); Grillo, C. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Infante, L. [Departamento de Astronoia y Astrofisica, Pontificia Universidad Catolica de Chile, V. Mackenna 4860, Santiago 22 (Chile); and others

    2014-03-20

    Growing observational evidence indicates that nebular line emission has a significant impact on the rest-frame optical fluxes of z ∼ 5-7 galaxies. This line emission makes z ∼ 5-7 galaxies appear more massive, with lower specific star-formation rates (sSFRs). However, corrections for this line emission have been difficult to perform reliably because of huge uncertainties on the strength of such emission at z ≳ 5.5. In this paper, we present the most direct observational evidence thus far for ubiquitous high-equivalent-width (EW) [O III] + Hβ line emission in Lyman-break galaxies at z ∼ 7, and we present a strategy for an improved measurement of the sSFR at z ∼ 7. We accomplish this through the selection of bright galaxies in the narrow redshift window z ∼ 6.6-7.0 where the Spitzer/Infrared Array Camera (IRAC) 4.5 μm flux provides a clean measurement of the stellar continuum light, in contrast with the 3.6 μm flux, which is contaminated by the prominent [O III] + Hβ lines. To ensure a high signal-to-noise ratio for our IRAC flux measurements, we consider only the brightest (H {sub 160} < 26 mag) magnified galaxies we have identified behind galaxy clusters. It is remarkable that the mean rest-frame optical color for our bright seven-source sample is very blue, [3.6]-[4.5] = –0.9 ± 0.3. Such blue colors cannot be explained by the stellar continuum light and require that the rest-frame EW of [O III] + Hβ is greater than 637 Å for the average source. The four bluest sources from our seven-source sample require an even more extreme EW of 1582 Å. We can also set a robust lower limit of ≳ 4 Gyr{sup –1} on the sSFR of our sample based on the mean spectral energy distribution.

  19. Difference between Spatial Distributions of the H-alpha Kernels and Hard X-Ray Sources in a Solar Flare

    Asai, Ayumi; Masuda, Satoshi; Yokoyama, Takaaki; Shimojo, Masumi; Isobe, Hiroaki; Kurokawa, Hiroki; Shibata, Kazunari

    2002-01-01

    We present the relation of the spatial distribution of H-alpha kernels with the distribution of hard X-ray (HXR) sources seen during the 2001 April 10 solar flare. This flare was observed in H-alpha with the (Sartorius) telescope at Kwasan Observatory, Kyoto University, and in hard X-rays (HXRs) with the Hard X-ray Telescope (HXT) onboard Yohkoh. We compared the spatial distribution of the HXR sources with that of the H-alpha kernels. While many H-alpha kernels are found to brighten successiv...

  20. Discovery of H alpha absorption in the unusual broad absorption line quasar SDSS J083942.11+380526.3

    Aoki, Kentaro; Iwata, Ikuru; Ohta, Kouji; Ando, Masataka; Akiyama, Masayuki; Tamura, Naoyuki

    2006-01-01

    We discovered an H alpha absorption in a broad H alpha emission line of an unusual broad absorption line quasar, SDSS J083942.11+380526.3 at z=2.318, by near-infrared spectroscopy with the Cooled Infrared Spectrograph and Camera for OHS (CISCO) on the Subaru telescope. The Presence of non-stellar H alpha absorption is known only in the Seyfert galaxy NGC 4151 to date, thus our discovery is the first case for quasars. The H alpha absorption line is blueshifted by 520 km/s relative to the H alp...

  1. First Simultaneous Observation of H-alpha Moreton Wave, EUV Wave, and Filament/Prominence Oscillations

    Asai, Ayumi; Isobe, Hiroaki; Kitai, Reizaburo; UeNo, Satoru; Nagata, Shin'ichi; Morita, Satoshi; Nishida, Keisuke; Shiota, Daikou; Oi, Akihito; Akioka, Maki; Shibata, Kazunari

    2011-01-01

    We report on the first simultaneous observation of an H-alpha Moreton wave, the corresponding EUV fast coronal waves, and a slow and bright EUV wave (typical EIT wave). Associated with an X6.9 flare that occurred on 2011 August 9 at the active region NOAA 11263, we observed a Moreton wave in the H-alpha images taken by the Solar Magnetic Activity Research Telescope (SMART) at Hida Observatory of Kyoto University. In the EUV images obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) we found not only the corresponding EUV fast "bright" coronal wave, but also the EUV fast "faint" wave that is not associated with the H-alpha Moreton wave. We also found a slow EUV wave, which corresponds to a typical EIT wave. Furthermore, we observed, for the first time, the oscillations of a prominence and a filament, simultaneously, both in the H-alpha and EUV images. To trigger the oscillations by the flare-associated coronal disturbance, we expect a coronal wave as fast as the fast...

  2. H$\\alpha$ and Free-Free Emission from the WIM

    Dong, Ruobing

    2010-01-01

    Recent observations have found the ratio of H$\\alpha$ to free-free radio continuum to be surprisingly high in the diffuse ionized ISM (the so-called WIM), corresponding to an electron temperature of only $\\sim$3000~K. Such low temperatures were unexpected in gas that was presumed to be photoionized. We consider a 3-component model for the observed diffuse emission, consisting of a mix of (1) photoionized gas, (2) gas that is recombining and cooling, and (3) cool H~I gas. This model can successfully reproduce the observed intensities of free-free continuum, H$\\alpha$, and collisionally-excited lines such as [\\ion{N}{2}]6583. To reproduce the low observed value of free-free to H$\\alpha$, the PAH abundance in the photoionized regions must be lowered by a factor $\\sim$3, and $\\sim$15\\% of the diffuse H$\\alpha$ must be reflected from dust grains, as suggested by \\citet{Wood+Reynolds_1999}.

  3. H alpha Star Formation Rates in Massive Galaxies at z ~ 1

    Twite, Jonathan W; Buitrago, Fernando; Noeske, Kai; Weiner, Benjamin J; Acosta-Pulido, Jose A; Bauer, Amanda E

    2011-01-01

    We present a near-infrared spectroscopic study of a stellar mass selected sample of galaxies at z~1 utilising the LIRIS multi-object spectrograph on the WHT. We detect continuum, and the H alpha line for our sample, which is one of the better direct tracers of star formation in external galaxies. We spectroscopically measure the H alpha emission from 41 massive (M_{*}>10^{10.5} Msol) galaxies taken from the POWIR Survey with spectroscopic redshifts 0.410^{11} Msol which are detected in H alpha emission at z<0.9. We furthermore find that the fraction of galaxies with H alpha emission drops steadily and significantly with redder (U-B) colours at z~1, and that the SSFR drops with increasing (U-B) colour for galaxies at all masses. By investigating the SFR-mass relation we find that the SFR is roughly constant with mass, in possible contrast to previous work, and that the specific star formation rate (SSFR) is lower in the most massive galaxies. The scatter in the SFR vs. mass relationship is very small for th...

  4. The Properties of H{\\alpha} Emission-Line Galaxies at $z$ = 2.24

    An, F X; Wang, W -H; Huang, J -S; Kong, X; Wang, J -X; Fang, G W; Zhu, F; Gu, Q -S; Wu, H; Hao, L; Xia, X -Y

    2014-01-01

    Using deep narrow-band $H_2S1$ and $K_{s}$-band imaging data obtained with CFHT/WIRCam, we identify a sample of 56 H$\\alpha$ emission-line galaxies (ELGs) at $z=2.24$ with the 5$\\sigma$ depths of $H_2S1=22.8$ and $K_{s}=24.8$ (AB) over 383 arcmin$^{2}$ area in the ECDFS. A detailed analysis is carried out with existing multi-wavelength data in this field. Three of the 56 H$\\alpha$ ELGs are detected in Chandra 4 Ms X-ray observation and two of them are classified as AGNs. The rest-frame UV and optical morphologies revealed by HST/ACS and WFC3 deep images show that nearly half of the H$\\alpha$ ELGs are either merging systems or with a close companion, indicating that the merging/interacting processes play a key role in regulating star formation at cosmic epoch z=2-3; About 14% are too faint to be resolved in the rest-frame UV morphology due to high dust extinction. We estimate dust extinction form SEDs. We find that dust extinction is generally correlated with H$\\alpha$ luminosity and stellar mass (SM). Our res...

  5. Anisotropy in broad component of H$\\alpha$ line in the magnetospheric device RT-1

    Kawazura, Yohei; Yoshida, Zensho; Nishiura, Masaki; Nogami, Tomoaki; Kashyap, Ankur; Yano, Yoshihisa; Saitoh, Haruhiko; Yamasaki, Miyuri; Mushiake, Toshiki; Nakatsuka, Masataka

    2016-01-01

    Temperature anisotropy in broad component of H$\\alpha$ line was found in the ring trap 1 (RT-1) device by Doppler spectroscopy. Since hot hydrogen neutrals emitting a broad component are mainly produced by charge exchange between neutrals and protons, the anisotropy in the broad component is the evidence of proton temperature anisotropy generated by betatron acceleration.

  6. DISCOVERY OF AN H{alpha} EMITTING DISK AROUND THE SUPERMASSIVE BLACK HOLE OF M31

    Menezes, R. B.; Steiner, J. E.; Ricci, T. V., E-mail: robertobm@astro.iag.usp.br [Instituto de Astronomia Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, Rua do Matao 1226, Cidade Universitaria, Sao Paulo, SP CEP 05508-090 (Brazil)

    2013-01-10

    Due to its proximity, the mass of the supermassive black hole in the nucleus of the Andromeda galaxy (M31), the most massive black hole in the Local Group of galaxies, has been measured by several methods involving the kinematics of a stellar disk which surrounds it. We report here the discovery of an eccentric H{alpha} emitting disk around the black hole at the center of M31 and show how modeling this disk can provide an independent determination of the mass of the black hole. Our model implies a mass of 5.0{sup +0.8}{sub -1.0} Multiplication-Sign 10{sup 7} M{sub Sun} for the central black hole, consistent with the average of determinations by methods involving stellar dynamics, and compatible (at 1{sigma} level) with measurements obtained from the most detailed models of the stellar disk around the central black hole. This value is also consistent with the M-{sigma} relation. In order to make a comparison, we applied our simulation on the stellar kinematics in the nucleus of M31 and concluded that the parameters obtained for the stellar disk are not formally compatible with the parameters obtained for the H{alpha} emitting disk. This result suggests that the stellar and the H{alpha} emitting disks are intrinsically different from each other. A plausible explanation is that the H{alpha} emission is associated with a gaseous disk. This hypothesis is supported by the detection of traces of weaker nebular lines in the nuclear region of M31. However, we cannot exclude the possibility that the H{alpha} emission is, at least partially, generated by stars.

  7. Mapping High-Velocity H-alpha and Lyman-alpha Emission from Supernova 1987A

    France, Kevin; McCray, Richard; Fransson, Claes; Larsson, Josefin; Frank, Kari A.; Burrows, David N.; Challis, Peter; Kirshner, Robert P.; Chevalier, Roger A.; Garnavich, Peter; Heng, Kevin; Lawrence, Stephen S.; Lundqvist, Peter; Smith, Nathan; Sonneborn, George

    2015-01-01

    We present new Hubble Space Telescope images of high-velocity H-alpha and Lyman-alpha emission in the outer debris of SN 1987A. The H-alpha images are dominated by emission from hydrogen atoms crossing the reverse shock. For the first time we observe emission from the reverse shock surface well above and below the equatorial ring, suggesting a bipolar or conical structure perpendicular to the ring plane. Using the H-alpha imaging, we measure the mass flux of hydrogen atoms crossing the reverse shock front, in the velocity intervals (-7,500 < V(sub obs) < -2,800 km/s) and (1,000 < V(sub obs) < 7,500 km/s), ?M(sub H) = 1.2 × 10(exp -3) M/ y. We also present the first Lyman-alpha imaging of the whole remnant and new Chandra X-ray observations. Comparing the spatial distribution of the Lyman-alpha and X-ray emission, we observe that the majority of the high-velocity Lyman-alpha emission originates interior to the equatorial ring. The observed Lyman-alpha/H-alpha photon ratio, R(L-alpha/H-alpha) approx. = 17, is significantly higher than the theoretically predicted ratio of approx. = 5 for neutral atoms crossing the reverse shock front. We attribute this excess to Lyman-alpha emission produced by X-ray heating of the outer debris. The spatial orientation of the Lyman-alpha and X-ray emission suggests that X-ray heating of the outer debris is the dominant Lyman-alpha production mechanism in SN 1987A at this phase in its evolution.

  8. Formation of Raman Scattering Wings around H alpha, H beta and Pa alpha in Active Galactic Nuclei

    Chang, Seok-Jun; Di Mille, Francesco; Angeloni, Rodolfo; Palma, Tali; Lee, Hee-Won

    2015-01-01

    Powered by a supermassive black hole with an accretion disk, the spectra of active galactic nuclei (AGNs) are characterized by prominent emission lines including Balmer lines. The unification schemes of AGNs require the existence of a thick molecular torus that may hide the broad emission line region from the view of observers near the equatorial direction. In this configuration, one may expect that the far UV radiation from the central engine can be Raman scattered by neutral hydrogen to reappear around Balmer and Paschen emission lines which can be identified with broad wings. We produce H$\\alpha$, H$\\beta$ and Pa$\\alpha$ wings using a Monte Carlo technique to investigate their properties. The neutral scattering region is assumed to be a cylindrical torus specified by the inner and outer radii and the height. While the covering factor of the scattering region affects the overall strengths of the wings, the wing widths are primarily dependent on the neutral hydrogen column density $N_{\\rm HI}$ being roughly ...

  9. Variations of flaring kernel sizes in various parts of the H-alpha line profile

    Radziszewski, K

    2012-01-01

    We analyze the temporal variations of the sizes and emission intensities of thirtyone flaring kernels in various parts of the H{\\alpha} line profile. We have found that the areas of all kernels decrease systematically when observed in consecutive wavelengths toward the wings of the H{\\alpha} line, but their areas and emission intensity vary in time. Our results are in agreement with the commonly accepted model of the glass-shaped lower parts of the magnetic flaring loops channelling high energy variable particle beams toward the chromospheric plasma. High time resolution spectral-imaging data used in our work were collected using the Large Coronagraph and Horizontal Telescope equipped with the Multi-channel Subtractive Double Pass Spectrograph and the Solar Eclipse Coronal Imaging System (MSDP-SECIS) at the Bia{\\l}k\\'ow Observatory of the University of Wroc{\\l}aw, Poland.

  10. Extending the $h\\alpha$ survey for the local volume galaxies

    Karachentsev, I D; Kaisina, E I

    2015-01-01

    Images in the $H\\alpha$ emission line are presented for 35 nearby objects observed with the 6-m BTA telescope. Three of them, NGC 3377, NGC 3384, and NGC 3390, are bright E and S0 galaxies, one is an edge-on Sd galaxy UGC 7321, two are remote globular clusters associated with M 31, and the rest are dwarf galaxies of morphological types dIr, dTr, dSph, BCD, and Sm. The measured $H\\alpha$ fluxes are used to estimate the integral $(SFR)$ and specific $(sSFR)$ star formation rates for these galaxies. The values of $\\log[sSFR]$ for all these objects lie below a limit of $-0.4$(Gyr$^{-1})$. We note that the emission disk for the nearest superthin edge-on galaxy UGC 7321 has an extremely large axis ratio of $a/b = 38.$

  11. Canes Venatici I cloud of galaxies seen in the H-alpha line

    Kaisin, S S

    2007-01-01

    We present results of H-alpha imaging for 42 galaxies in the nearby low-density cloud Canes Venatici I populated mainly by late-type objects. Estimates of the H-alpha flux and integrated star formation rate (SFR) are now available for all 78 known members of this scattered system, spanning a large range in luminosity, surface brightness, HI content and SFR. Distributions of the CVnI galaxies versus their SFR, blue absolute magnitude and total hydrogen mass are given in comparison with those for a population of the nearby virialized group around M81. We found no essential correlation between star formation activity in a galaxy and its density environment. A bulk of CVnI galaxies had enough time to generate their baryon mass with the observed SFR. Most of them possess also a supply of gas sufficient to maintain their observed SFR's during the next Hubble time.

  12. Spectropolarimetry of Broad H_alpha Lines and Geometry of the BLR

    Cohen, M H; Cohen, Marshall H.; Martel, Andre' R.

    2001-01-01

    In a small fraction of Broad Line Radio Galaxies (BLRG) and Seyfert 1 galaxies, the polarization position angle rotates across the broad emission lines, especially at H_alpha. An understanding of this behavior can potentially yield important information on the scattering geometry in the nucleus. We show two examples of this phenomenon, 3C 445, a BLRG, and Mrk 231, a Seyfert 1, and present an equatorial scattering model that explains some of its features in a straightforward way.

  13. Lifetimes of enhanced chromospheric network features near active regions. [from solar centerline H alpha filtergrams

    Prata, S. W.

    1973-01-01

    Centerline H alpha filtergrams providing nearly full-day coverage of the sun are used to study the lifetimes of enhanced network features near active regions. In the two cases studied the fraction remaining of those features present at an original epoch remains near unity for 50 hr, then drops exponentially with a 1/e decay time of 30 hr. Histories of representative enhanced network features are discussed.-

  14. Spatial Correlation Between Dust and H$\\alpha$ Emission in Dwarf Irregular Galaxies

    Jimmy,; Saintonge, Amélie; Accurso, Gioacchino; Brough, Sarah; Oliva-Altamirano, Paola; Salmon, Brett; Forrest, Ben

    2016-01-01

    Using a sample of dwarf irregular galaxies selected from the ALFALFA blind HI-survey and observed using the VIMOS IFU, we investigate the relationship between H$\\alpha$ emission and Balmer optical depth ($\\tau_{\\text{b}}$). We find a positive correlation between H$\\alpha$ luminosity surface density and Balmer optical depth in 8 of 11 at $\\geq$ 0.8$\\sigma$ significance (6 of 11 at $\\geq$ 1.0$\\sigma$) galaxies. Our spaxels have physical scales ranging from 30 to 80 pc, demonstrating that the correlation between these two variables continues to hold down to spatial scales as low as 30 pc. Using the Spearman's rank correlation coefficient to test for correlation between $\\Sigma_{\\text{H}\\alpha}$ and $\\tau_{\\text{b}}$ in all the galaxies combined, we find $\\rho = 0.39$, indicating a positive correlation at 4$\\sigma$ significance. Our low stellar-mass galaxy results are in agreement with observations of emission line regions in larger spiral galaxies, indicating that this relationship is independent of the size of ...

  15. Star-formation properties of Hickson Compact Groups based on deep H{\\alpha} imaging

    Eigenthaler, Paul; Verdugo, Miguel; Ziegler, Bodo

    2015-01-01

    We present deep H{\\alpha} imaging of seven Hickson Compact Groups (HCGs) using the 4.1m Southern Astrophysics Research (SOAR) Telescope. The high spatial resolution of the observations allow us to study both the integrated star-formation properties of the main galaxies as well as the 2D distribution of star-forming knots in the faint tidal arms that form during interactions between the individual galaxies. We derive star-formation rates and stellar masses for group members and discuss their position relative to the main sequence of star-forming galaxies. Despite the existence of tidal features within the galaxy groups, we do not find any indication for enhanced star-formation in the selected sample of HCGs. We study azimuthally averaged H{\\alpha} profiles of the galaxy disks and compare them with the g' and r' surface-brightness profiles. We do not find any truncated galaxy disks but reveal that more massive galaxies show a higher light concentration in H{\\alpha} than less massive ones. We also see that galax...

  16. Observational and theoretical constraints for an H$\\alpha$-halo around the Crab Nebula

    Tziamtzis, A; Lundqvist, P; Sollerman, J

    2009-01-01

    We searched for a fast moving H$\\alpha$ shell around the Crab nebula. Such a shell could account for this supernova remnant's missing mass, and carry enough kinetic energy to make SN 1054 a normal Type II event. Deep H$\\alpha$ images were obtained with WFI at the 2.2m MPG/ESO telescope and with MOSCA at the 2.56m NOT. The data are compared with theoretical expectations derived from shell models with ballistic gas motion, constant temperature, constant degree of ionisation and a power law for the density profile. We reach a surface brightness limit of $5\\times10^{-8} ergs s^{-1} cm^{-2} sr^{-1}$. A halo is detected, but at a much higher surface brightness than our models of recombination emission and dust scattering predict. Only collisional excitation of Ly$\\beta$ with partial de-excitation to H$\\alpha$ could explain such amplitudes. We show that the halo seen is due to PSF scattering and thus not related to a real shell. We also investigated the feasibility of a spectroscopic detection of high-velocity H$\\al...

  17. On the H$\\alpha$ emission from the $\\beta$ Cephei system

    Schnerr, R S; Oudmaijer, R D; Telting, J H

    2006-01-01

    Be stars, which are characterised by intermittent emission in their hydrogen lines, are known to be fast rotators. This fast rotation is a requirement for the formation of a Keplerian disk, which in turn gives rise to the emission. However, the pulsating, magnetic B1IV star $\\beta$ Cephei is a very slow rotator that still shows H$\\alpha$ emission episodes like in other Be stars, contradicting current theories. We investigate the hypothesis that the H$\\alpha$ emission stems from the spectroscopically unresolved companion of $\\beta$ Cep. Spectra of the two unresolved components have been separated in the 6350-6850\\AA range with spectro-astrometric techniques, using 11 longslit spectra obtained with ALFOSC at the Nordic Optical Telescope, La Palma. We find that the H$\\alpha$ emission is not related to the primary in $\\beta$ Cep, but is due to its 3.4 magnitudes fainter companion. This companion has been resolved by speckle techniques, but it remains unresolved by traditional spectroscopy. The emission extends fr...

  18. The Lyman alpha reference sample. VII. Spatially resolved H$\\alpha$ kinematics

    Herenz, Edmund Christian; Orlitova, Ivana; Hayes, Matthew; Östlin, Göran; Cannon, John M; Roth, Martin M; Bik, Arjan; Pardy, Stephen; Otí-Floranes, Héctor; Mas-Hesse, J Miguel; Adamo, Angela; Atek, Hakim; Duval, Florent; Guaita, Lucia; Kunth, Daniel; Laursen, Peter; Melinder, Jens; Puschnig, Johannes; Rivera-Thorsen, Thøger E; Schaerer, Daniel; Verhamme, Anne

    2015-01-01

    We present integral field spectroscopic observations with the Potsdam Multi Aperture Spectrophotometer of all 14 galaxies in the $z\\sim 0.1$ Lyman Alpha Reference Sample (LARS). We produce 2D line of sight velocity maps and velocity dispersion maps from the Balmer $\\alpha$ (H$\\alpha$) emission in our data cubes. These maps trace the spectral and spatial properties of the LARS galaxies' intrinsic Ly$\\alpha$ radiation field. We show our kinematic maps spatially registered onto the Hubble Space Telescope H$\\alpha$ and Lyman $\\alpha$ (Ly$\\alpha$) images. Only for individual galaxies a causal connection between spatially resolved H$\\alpha$ kinematics and Ly$\\alpha$ photometry can be conjectured. However, no general trend can be established for the whole sample. Furthermore, we compute non-parametric global kinematical statistics -- intrinsic velocity dispersion $\\sigma_0$, shearing velocity $v_\\mathrm{shear}$, and the $v_\\mathrm{shear}/\\sigma_0$ ratio -- from our kinematic maps. In general LARS galaxies are charac...

  19. The H-alpha surface brightness - radius relation: a robust statistical distance indicator for planetary nebulae

    Frew, David J; Bojicic, I S

    2016-01-01

    Measuring the distances to Galactic planetary nebulae (PNe) has been an intractable problem for many decades. We have now established a robust optical statistical distance indicator, the H-alpha surface brightness -radius or S-r relation, which addresses this problem. We developed this relation from a critically evaluated sample of primary calibrating PNe. The robust nature of the method results from our revised calibrating distances with significantly reduced systematic uncertainties, and the recent availability of high-quality data, including updated nebular diameters and integrated H-alpha fluxes. The S-r technique is simple in its application, requiring only an angular size, an integrated H-alpha flux, and the reddening to the PN. From these quantities, an intrinsic radius is calculated, which when combined with the angular size, yields the distance directly. Furthermore, we have found that optically thick PNe tend to populate the upper bound of the trend, while optically-thin PNe fall along the lower bou...

  20. The Gaia-ESO Survey: Catalogue of H$\\alpha$ emission stars

    Traven, Gregor; Van Eck, Sophie; Klutsch, Alexis; Bonito, Rosaria; Lanzafame, Alessandro C; Alfaro, Emilio J; Bayo, Amelia; Bragaglia, Angela; Costado, María Teresa; Damiani, Francesco; Flaccomio, Ettore; Frasca, Antonio; Hourihane, Anna; Jimenez-Esteban, Fran; Lardo, Carmela; Morbidelli, Lorenzo; Pancino, Elena; Prisinzano, Loredana; Sacco, Germano G; Worley, Clare C

    2015-01-01

    We discuss the properties of H$\\alpha$ emission stars across the sample of 22035 spectra from the Gaia-ESO Survey internal data release, observed with the GIRAFFE instrument and largely belonging to stars in young open clusters. Automated fits using two independent Gaussian profiles and a third component that accounts for the nebular emission allow us to discern distinct morphological types of H$\\alpha$ line profiles with the introduction of a simplified classification scheme. All in all we find 3765 stars with intrinsic emission and sort their spectra into eight distinct morphological categories: single--component emission, emission blend, sharp emission peaks, double emission, P-Cygni, inverted P-Cygni, self--absorption, and emission in absorption. We have more than one observation for 1430 stars in our sample, thus allowing a quantitative discussion of the degree of variability of H$\\alpha$ emission profiles, which is expected for young, active objects. We present a catalogue of stars with properties of th...

  1. Mapping High-velocity H-alpha and Lyman-alpha Emission from Supernova 1987A

    France, Kevin; Fransson, Claes; Larsson, Josefin; Frank, Kari A; Burrows, David N; Challis, Peter; Kirshner, Robert P; Chevalier, Roger A; Garnavich, Peter; Heng, Kevin; Lawrence, Stephen S; Lundqvist, Peter; Smith, Nathan; Sonneborn, George

    2015-01-01

    We present new {\\it Hubble Space Telescope} images of high-velocity H-$\\alpha$ and Lyman-$\\alpha$ emission in the outer debris of SN~1987A. The H-$\\alpha$ images are dominated by emission from hydrogen atoms crossing the reverse shock. For the first time we observe emission from the reverse shock surface well above and below the equatorial ring, suggesting a bipolar or conical structure perpendicular to the ring plane. Using the H$\\alpha$ imaging, we measure the mass flux of hydrogen atoms crossing the reverse shock front, in the velocity intervals ($-$7,500~$<$~$V_{obs}$~$<$~$-$2,800 km s$^{-1}$) and (1,000~$<$~$V_{obs}$~$<$~7,500 km s$^{-1}$), $\\dot{M_{H}}$ = 1.2~$\\times$~10$^{-3}$ M$_{\\odot}$ yr$^{-1}$. We also present the first Lyman-$\\alpha$ imaging of the whole remnant and new $Chandra$ X-ray observations. Comparing the spatial distribution of the Lyman-$\\alpha$ and X-ray emission, we observe that the majority of the high-velocity Lyman-$\\alpha$ emission originates interior to the equatorial...

  2. Is the Broad-Line Region Clumped or Smooth? Constraints from the H alpha Profile in NGC 4395, the Least Luminous Seyfert 1 Galaxy

    Laor, A; Ho, L C; Filippenko, A V; Laor, Ari; Barth, Aaron J.; Ho, Luis C.; Filippenko, Alexei V.

    2005-01-01

    The origin and configuration of the gas which emits broad lines in Type I active galactic nuclei is not established yet. The lack of small-scale structure in the broad emission-line profiles is consistent with a smooth gas flow, or a clumped flow with many small clouds. An attractive possibility for the origin of many small clouds is the atmospheres of bloated stars, an origin which also provides a natural mechanism for the cloud confinement. Earlier studies of the broad-line profiles have already put strong lower limits on the minimum number of such stars, but these limits are sensitive to the assumed width of the lines produced by each cloud. Here we revisit this problem using high-resolution Keck spectra of the H alpha line in NGC 4395, which has the smallest known broad-line region (~10^14 cm). Only a handful of the required bloated stars (each having r~10^14 cm) could fit into the broad-line region of NGC 4395, yet the observed smoothness of the H alpha line implies a lower limit of ~10^4-10^5 on the num...

  3. A Spectroscopic Study of the H-alpha Surface Brightness Profiles in the Outer Disks of Galaxies

    Christlein, Daniel; Bland-Hawthorn, Joss

    2010-01-01

    The surface brightness profile of H-alpha emission in galaxies is generally thought to be confined by a sharp truncation, sometimes speculated to coincide with a star formation threshold. Over the past years, observational evidence for both old and young stellar populations, as well as individual H II regions, has demonstrated that the outer disk is an actively evolving part of a galaxy. To provide constraints on the origin of the aforementioned H-alpha truncation and the relation of H-alpha emission in the outer disk to the underlying stellar population, we measure the shape of the outer H-alpha surface brightness profile of 15 isolated, edge-on late-type disk galaxies using deep, long-slit spectroscopy. Tracing H-alpha emission up to 50% beyond the optical radius, R_25, we find a composite H-alpha surface brightness profile, well described by a broken-exponential law, that drops more steeply in the outer disk, but which is not truncated. The stellar continuum and H-alpha surface brightness both exhibit a br...

  4. Optical Observations of M81 Galaxy Group in Narrow Band [SII] and H_alpha Filters: Holmberg IX

    Arbutina, B.

    2009-12-01

    Full Text Available We present observations of the nearby tidal dwarf galaxy Holmberg IX in M81 galaxy group in narrow band [SII] and H$alpha$ filters, carried out in March and November 2008 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for resident supernova remnants (identified as sources with enhanced [SII] emission relative to their H$alpha$ emission in this galaxy yielded no sources of this kind, besides M&H 10-11 or HoIX X-1. Nevertheless, we found a number of objects with significant H$alpha$ emission that probably represent uncatalogued HII regions.

  5. Optical Observations of M81 Galaxy Group in Narrow Band [SII] and H_alpha Filters: Holmberg IX

    Arbutina, B; Stavrev, K; Urosevic, D; Vukotic, B; Onic, D; 10.2298/SAJ0979087A

    2009-01-01

    We present observations of the nearby tidal dwarf galaxy Holmberg IX in M81 galaxy group in narrow band [SII] and H$\\alpha$ filters, carried out in March and November 2008 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for resident supernova remnants (identified as sources with enhanced [SII] emission relative to their H$\\alpha$ emission) in this galaxy yielded no sources of this kind, besides M&H 10-11 or HoIX X-1. Nevertheless, we found a number of objects with significant H$\\alpha$ emission that probably represent uncatalogued HII regions.

  6. A Model for the Scattered Light Contribution and Polarization of the Diffuse H$\\alpha$ Galactic Background

    Wood, Kenneth; Reynolds, Ron

    1999-01-01

    We present Monte Carlo simulations of the Diffuse H$\\alpha$ Galactic Background. Our models comprise direct and multiply scattered H$\\alpha$ radiation from the kpc scaleheight Warm Ionized Medium and midplane H II regions. The scattering is off dust that is assumed to be well mixed with the gas, with an axisymmetric density distribution taken from the literature. The results of our simulations are all-sky H$\\alpha$ images that enable us to separate out the contributions of direct and scattere...

  7. Discovery of Two Apparent Novae in M81 and H-alpha Confirmation of PNV J09554276+6904230

    Hornoch, K.; Tudor, V.; Vaduvescu, O.

    2014-02-01

    We report the discovery of two apparent novae in M81 on a co-added 1600-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma under ~1.3" seeing on 2014 Feb. 21.018 UT. The new objects are well visible on the co-added image (see the finding charts linked below), but are not present on numerous narrow-band H-alpha archival images from the INT down to limiting magnitude as faint as H-alpha = 22.3.

  8. Models of Diffuse H{\\alpha} in the Interstellar Medium: The Relative Contributions from In Situ Ionisation and Dust Scattering

    Barnes, Joanna E; Hill, Alex S; Haffner, L Matthew

    2014-01-01

    Using three dimensional Monte Carlo radiation transfer models of photoionisation and dust scattering, we explore different components of the widespread diffuse H$\\alpha$ emission observed in the interstellar medium of the Milky Way and other galaxies. We investigate the relative contributions of H$\\alpha$ from recombination emission in ionised gas and H$\\alpha$ that originates in H{\\sc ii} regions near the Galactic midplane and scatters off high altitude dust in the diffuse interstellar medium. For the radiation transfer simulations we consider two geometries for the interstellar medium: a three dimensional fractal geometry that reproduces the average density structure inferred for hydrogen in the Milky Way, and a density structure from a magneto hydrodynamic simulation of a supernovae driven turbulent interstellar medium. Although some sight lines that are close to H{\\sc ii} regions can be dominated by scattered light, overall we find that less than $\\sim 20\\%$ of the total H$\\alpha$ intensity in our simulat...

  9. Standard Stars for the BYU H-alpha Photometric System (Abstract)

    Joner, M.; Hintz, E.

    2015-12-01

    (Abstract only) We present primary standard stars for the BYU H-alpha photometric system. This system is similar to the H-beta photometric system that is often used with the intermediate band uvby system. Both systems use the difference between magnitudes measured in a wide (15-20-nm) and narrow (3-nm) bandpass centered on one of the strong Balmer lines of hydrogen to establish a color index. Line indices formed in this manner are independent of atmospheric extinction and interstellar reddening. These indices provide intrinsic measures of effective temperature for stars with spectral types between B and G. The present primary standard stars for the BYU system as established using spectroscopic observations that cover the region between the H-alpha and H-beta lines. The indices were formed using synthetic photometry reductions to convolve ideal filter profiles with the observed spectra. The number of observations per star is generally in excess of 25. Some stars have been observed more than 100 times over a period of 7 years. The typical error per observation for these stars is on the order of 1-3 mmag. In addition to the standard field stars, we present H-alpha and H-beta observations of individual stars that are members of selected open clusters. These include the Hyades, Pleiades, Coma, and NGC 752 clusters. Additional stars that exhibit varying degrees of hydrogen emission are easily distinguished in a plot of the alpha-beta plane. We have found that candidates for emission line objects, high mass x-ray binaries, and young stellar objects are readily identified in our alpha-beta plots. We acknowledge continued support from the BYU College of Physical and Mathematical Sciences as well as support from NSF Grant AST #0618209. We also thank the Dominion Astrophysical Observatory for continued allocation of robotic observing time for spectroscopy on the 1.2-m telescope.

  10. LkH-alpha 101 - The stellar wind, the surrounding nebula, and an associated radio star cluster

    Becker, Robert H.; White, Richard L.

    1988-01-01

    Radio observations of LkH-alpha 101 have been taken to determine the characteristics of the stellar wind from the central star as well as to image the surrounding nebulosity. They also revealed the presence of a high concentration of weak compact radio sources in the neighborhood of LkH-alpha 101, four of which have optical stellar counterparts. Spectra of three of the stars indicate two T Tauri stars and a highly obscured B star.

  11. LkH-alpha 101 - the stellar wind, the surrounding nebula, and an associated radio star cluster

    Radio observations of LkH-alpha 101 have been taken to determine the characteristics of the stellar wind from the central star as well as to image the surrounding nebulosity. They also revealed the presence of a high concentration of weak compact radio sources in the neighborhood of LkH-alpha 101, four of which have optical stellar counterparts. Spectra of three of the stars indicate two T Tauri stars and a highly obscured B star. 15 references

  12. Measurement of Star-Formation Rate from H-alpha in field galaxies at z=1

    Glazebrook, Karl; Blake, Chris; Economou, Frossie; Lilly, Simon; Colless, Matthew

    1998-01-01

    We report the results of J-band infrared spectroscopy of a sample of 13 z=1 field galaxies drawn from the Canada-France Redshift Survey, targeting galaxies whose redshifts place the rest frame H-alpha line emission from HII regions in between the bright night sky OH lines. As a result we detect emission down to a flux limit of ~10^{-16} ergs cm^{-2} s^{-1} corresponding to a luminosity limit of ~10^{41} ergs at this redshift for a H_0=50 km s^{-1} Mpc,^{-1} q_0=0.5 cosmology. From these lumin...

  13. Approximate formulation of redistribution in the Ly-alpha, Ly-beta, H-alpha system

    Cooper, J.; Ballagh, R. J.; Hubeny, I.

    1989-01-01

    Simple approximate formulas are given for the coupled redistribution of Ly-alpha, Ly-beta, and H-alpha, by using well-defined approximations to an essentially exact formulation. These formulas incorporate all the essential physics including Raman scattering, lower state radiative decay, and correlated terms representing emission during a collision which must be retained in order that the emission coefficients are properly behaved in the line wings. Approximate expressions for the appropriate line broadening parameters are collected. Finally, practical expressions for the source functions are given. These are formulated through newly introduced nonimpact redistribution functions, which are shown to be reasonably approximated by existing (ordinary and generalized) redistribution functions.

  14. GH $\\alpha$ FaS : Galaxy H-alpha Fabry-Perot System for the WHT

    Hernandez, O.; Fathi, K; Carignan, C.; Beckman, J.; Gach, J. -L.; Balard, P.; Amram, P.; J. Boulesteix; Corradi, R.L.M.; de Denus-Baillargeon, M-M.; Epinat, B.; Relao, M.; Thibault, S.; Valle, P.

    2008-01-01

    GH$\\alpha$FaS a new Fabry-Perot system, is now available at the William Herschel Telescope. It was mounted, for the first time, at the Nasmyth focus of the 4.2 meter WHT on La Palma in July 2007. Using modern technology, with a spectral resolution of the order R$\\sim$15000, and with a seeing limited spatial resolution, GH$\\alpha$FaS will provide a new look at the H$\\alpha$ -emitting gas over a 4.8 arcminutes circular field in the nearby universe. Many science programs can be done on a 4.2 met...

  15. An impulsive solar burst observed in H-alpha, microwaves, and hard X-rays

    Gary, D. E.; Tang, F.

    1985-01-01

    H-alpha, microwave, and hard X-ray observations of an unusually short duration impulsive spike burst are presented. The observations are analyzed, and it is found that the single spike is in fact composed of two separate acceleration episodes. The differences found in the time profiles for the two components stress the role of the decay rate and lead to a simple explanation for the often observed delay of the microwave peak. The approximate numbers of electrons responsible for the two types of emission are derived and compared.

  16. HH 666: Different kinematics from H{\\alpha} and [Fe II] emission provide a missing link between jets and outflows

    Reiter, Megan; Kiminki, Megan M; Bally, John

    2015-01-01

    HH 666 is an externally irradiated protostellar outflow in the Carina Nebula for which we present new near-IR [Fe II] spectra obtained with the FIRE spectrograph at Magellan Observatory. Earlier H{\\alpha} and near-IR [Fe II] imaging revealed that the two emission lines trace substantially different morphologies in the inner ~40" of the outflow. H{\\alpha} traces a broad cocoon that surrounds the collimated [Fe II] jet that extends throughout the parent dust pillar. New spectra show that this discrepancy extends to their kinematics. Near-IR [Fe II] emission traces steady, fast velocities of +/- 200 km/s from the eastern and western limbs of the jet. We compare this to a previously published H{\\alpha} spectrum that reveals a Hubble-flow velocity structure near the jet-driving source. New, second-epoch HST/ACS H{\\alpha} images reveal the lateral spreading of the H{\\alpha} outflow lobe away from the jet axis. H{\\alpha} proper motions also indicate a sudden increase in the mass-loss rate ~1000 yr ago, while steady ...

  17. Real-time flare detection in ground-based H$\\alpha$ imaging at Kanzelh\\"ohe Observatory

    Pötzi, Werner; Riegler, Gernot; Amerstorfer, Ulrike; Pock, Thomas; Temmer, Manuela; Polanec, Wolfgang; Baumgartner, Dietmar J

    2014-01-01

    Kanzelh\\"ohe Observatory (KSO) regularly performs high-cadence full-disk imaging of the solar chromosphere in the H$\\alpha$ and CaIIK spectrallines as well as the solar photosphere in white-light. In the frame of ESA's Space Situational Awareness (SSA) programme, a new system for real-time H$\\alpha$ data provision and automatic flare detection was developed at KSO. The data and events detected are published in near real-time at ESA's SSA Space Weather portal (http://swe.ssa.esa.int/web/guest/kso-federated). In this paper, we describe the H$\\alpha$ instrument, the image recognition algorithms developed, the implementation into the KSO H$\\alpha$ observing system and present the evaluation results of the real-time data provision and flare detection for a period of five months. The H$\\alpha$ data provision worked in $99.96$% of the images, with a mean time lag between image recording and online provision of 4s. Within the given criteria for the automatic image recognition system (at least three H$\\alpha$ images a...

  18. Red Star Forming Galaxies and Their Environment at z=0.4 Revealed by Panoramic H-alpha Imaging

    Koyama, Yusei; Nakata, Fumiaki; Shimasaku, Kazuhiro; Okamura, Sadanori

    2011-01-01

    We present a wide-field H-alpha imaging survey of the rich cluster CL0939+4713 (Abell 851) at z=0.41 with Suprime-Cam on the Subaru Telescope, using the narrow-band filter NB921. The survey is sensitive to active galaxies with star formation rates down to ~0.3Msun/yr throughout the 27'x27' field, and we identified 445 H-alpha emitters along the large-scale structures around the cluster. Using this sample, we find that (1) the fraction of H-alpha emitters is a strong function of environment and shows a clear decline toward the cluster central region. We also find that (2) the color of H-alpha emitters is clearly dependent on environment. The majority of the H-alpha emitters have blue colors with B-I<2, but we find H-alpha emitters with red colors as well. Such red emitters are very rare in the cluster center or its immediate surrounding regions, while they are most frequently found in groups located far away from the cluster center. These groups coincide with the environment where a sharp transition in gala...

  19. Morita Equivalence

    Barrett, Thomas William

    2015-01-01

    Logicians and philosophers of science have proposed various formal criteria for theoretical equivalence. In this paper, we examine two such proposals: definitional equivalence and categorical equivalence. In order to show precisely how these two well-known criteria are related to one another, we investigate an intermediate criterion called Morita equivalence.

  20. Two-dimensional H_alpha kinematics of bulgeless disk galaxies

    Neumayer, Nadine; Andersen, David; Sanchez, Sebastian F; Boeker, Torsten; Rix, Hans-Walter

    2011-01-01

    We present two-dimensional H_alpha velocity fields for 20 late-type, disk-dominated spiral galaxies, the largest sample to date with high-resolution H_alpha velocity fields for bulgeless disks. From these data we derive rotation curves and the location of the kinematic centers. The galaxy sample was selected to contain nucleated and non-nucleated galaxies, which allows us to investigate what impact the gas kinematics in the host disk have on the presence (or absence) of a nuclear star cluster. In general, we find that the velocity fields span a broad range of morphologies. While some galaxies show regular rotation, most have some degree of irregular gas motions. There appears to be no systematic difference in the kinematics of nucleated and non-nucleated disks. Due to the large fields of view of the integral field units we use, we are able to observe the flattening of the rotation curve in almost all of our sample galaxies. This makes modeling of the velocity fields relatively straight-forward. Due to the com...

  1. Deep H{\\alpha} Observations of NGC 253: a Very Extended and Possibly Declining Rotation Curve?

    Hlavacek-Larrondo, J; Daigle, O; de Denus-Baillargeon, M -M; Marcelin, M; Epinat, B; Hernandez, O

    2010-01-01

    This study presents a deep H{\\alpha} kinematical analysis of the Sculptor Group galaxy NGC253. The Fabry-Perot data were taken with the 36-cm Marseille Telescope in La Silla, Chile, using an EMCCD detector. Typical emission measures of ~0.1 cm^-6 pc are reached. The observations allow the detection of the Diffuse Ionized Gas component through [N II] emission at very large radii of 11.5', 12.8' and 19.0', on the receding side of the galaxy. No H{\\alpha} emission is observed at radii larger than the neutral component (11.5'). The very extended rotation curve confirms previous results and shows signs of a significant decline, on the order of 30 per cent vmax . Using the rotation data, mass models are constructed with and without the outer [N II] data points, and similar results are found. The declining part of the rotation curve is very well modeled, and seems to be truly declining.

  2. Shocks and Star Formation in Stephan's Quintet. I. Gemini Spectroscopy of H{\\alpha}-bright knots

    Konstantopoulos, I S; Guillard, P; Trancho, G; Cluver, M E; Bastian, N; Charlton, J C; Fedotov, K; Gallagher, S C; Smith, L J; Struck, C J

    2013-01-01

    We present a Gemini-GMOS spectroscopic study of HST-selected H{\\alpha}-emitting regions in Stephan's Quintet (HCG 92), a nearby compact galaxy group, with the aim of disentangling the processes of shock-induced heating and star formation in its intra-group medium. The $\\approx$40 sources are distributed across the system, but most densely concentrated in the $\\sim$kpc-long shock region. Their spectra neatly divide them into narrow- and and broad-line emitters, and we decompose the latter into three or more emission peaks corresponding to spatial elements discernible in HST imaging. The emission line ratios of the two populations of H{\\alpha}-emitters confirm their nature as H II regions (90% of the sample) or molecular gas heated by a shock-front propagating at $\\lesssim$300 km/s. Their redshift distribution reveals interesting three-dimensional structure with respect to gas-phase baryons, with no H II regions associated with shocked gas, no shocked regions in the intruder galaxy NGC 7318B, and a sharp bounda...

  3. Limits on Lyman Continuum escape from z=2.2 H-alpha emitting galaxies

    Sandberg, A; Melinder, J; Bik, A; Guaita, L

    2015-01-01

    The leakage of Lyman continuum photons from star forming galaxies is an elusive parameter. When observed, it provides a wealth of information on star formation in galaxies and the geometry of the interstellar medium, and puts constraints on the role of star forming galaxies in the reionization of the universe. H-alpha-selected galaxies at z~2 trace the highest star formation population at the peak of cosmic star formation history, providing a base for directly measuring Lyman continuum escape. Here we present this method, and highlight its benefits as well as caveats. We also use the method on 10 H-alpha emitters in the Chandra Deep Field South at z=2.2, also imaged with the Hubble Space Telescope in the ultraviolet. We find no individual Lyman continuum detections, and our stack puts a 5 sigma upper limit on the average absolute escape fraction of <24%, consistent with similar studies. With future planned observations, the sample sizes would rapidly increase and the method presented here would provide ver...

  4. Boxy H$\\alpha$ Emission Profiles in Star-Forming Galaxies

    Chen, Yan-Mei; Tremonti, Christy A; Shi, Yong; Jin, Yi-Fei

    2016-01-01

    We assemble a sample of disk star-forming galaxies from the Sloan Digital Sky Survey Data Release 7, studying the structure of H$\\alpha$ emission lines, finding a large fraction of this sample contains boxy H$\\alpha$ line profiles. This fraction depends on galaxy physical and geometric parameters in the following way: (1) it increases monotonically with star formation rate per unit area ($\\Sigma_{\\rm SFR}$), and stellar mass ($M_*$), with the trend being much stronger with $M_*$, from $\\sim$0% at $M_*=10^{10}M_{\\odot}$ to about 50% at $M_*=10^{11}M_\\odot$; (2) the fraction is much smaller in face-on systems than in edge-on systems. It increases with galaxy inclination ($i$) while $i < 60\\,^{\\circ}$ and is roughly a constant of 25% beyond this range; (3) for the sources which can be modeled well with two velocity components, blueshifted and redshifted from the systemic velocity, these is a positive correlation between the velocity difference of these two components and the stellar mass, with a slope similar...

  5. The Galactic Halo Ionizing Field and $H-\\alpha$ Distances to HVCs

    Bland-Hawthorn, J

    1998-01-01

    There has been much debate in recent decades as to what fraction of ionizing photons from star forming regions in the Galactic disk escape into the halo. The recent detection of the Magellanic Stream in optical line emission at the CTIO 4m and the AAT 3.9m telescopes may now provide the strongest evidence that at least some of the radiation escapes the disk completely. While the distance to the Magellanic Stream is uncertain, the observed H-alpha emission is most plausibly explained by photoionization due to hot, young stars. Our model requires that the mean Lyman-limit opacity perpendicular to the disk is tau close to unity. Within the context of this model, it now becomes possible to determine distances to high velocity clouds, and the 3D orientation of the Magellanic Stream. Here, we discuss complications of the model (e.g., porosity, topology), future tests, ongoing improvements, and the importance of H-alpha limb brightening from surface ionization. More speculatively, we propose a direct experiment for ...

  6. A Survey for H-alpha Emission from Late L dwarfs and T dwarfs

    Pineda, J Sebastian; Kirkpatrick, J Davy; Cotter, Garret; Kao, Melodie M; Mooley, Kunal

    2016-01-01

    Recently, studies of brown dwarfs have demonstrated that they possess strong magnetic fields and have the potential to produce radio and optical auroral emissions powered by magnetospheric currents. This emission provides the only window on magnetic fields in the coolest brown dwarfs and identifying additional benchmark objects is key to constraining dynamo theory in this regime. To this end, we conducted a new red optical (6300 - 9700 Angstrom) survey with the Keck telescopes looking for H-alpha emission from a sample of late L dwarfs and T dwarfs. Our survey gathered optical spectra for 29 targets, 18 of which did not have previous optical spectra in the literature, greatly expanding the number of moderate resolution (R~2000) spectra available at these spectral types. Combining our sample with previous surveys, we confirm an H-alpha detection rate of 9.2 (+3.5/-2.1) % for L and T dwarfs in the optical spectral range of L4 - T8. This detection rate is consistent with the recently measured detection rate for ...

  7. Quiet Sun H\\alpha\\ Transients and Corresponding Small-Scale Transition Region and Coronal Heating

    Henriques, V M J; Mathioudakis, M; Keenan, F P

    2016-01-01

    Rapid Blue- and Red-shifted Excursions (RBEs and RREs) are likely to be the on-disk counterparts of Type II spicules. Recently, heating signatures from RBEs/RREs have been detected in IRIS slit-jaw images dominated by transition-region lines around network patches. Additionally, signatures of Type II spicules have been observed in AIA diagnostics. The full-disk, ever-present nature of the AIA diagnostics should provide us with sufficient statistics to directly determine how important RBEs and RREs are to the heating of the transition region and corona. We find, with high statistical significance, that at least 11% of the low-coronal brightenings detected in a quiet-Sun region in 304, can be attributed to either RBEs or RREs as observed in H\\alpha, and a 6% match of 171 detected events to RBEs or RREs with very similar statistics for both types of H\\alpha\\ features. We took a statistical approach that allows for noisy detections in the coronal channels and provides us with a lower, but statistical significant,...

  8. The H alpha Galaxy Survey. IV. Star formation in the local Universe

    James, P A; Shane, N S; Baldry, I K; De Jong, R S

    2008-01-01

    We present an analysis of the star formation properties of field galaxies within the local volume out to a recession velocity limit of 3000 km/s. A parent sample of 863 star-forming galaxies is used to calculate a B-band luminosity function. This is then populated with star formation information from a subsample of 327 galaxies, for which we have H alpha imaging, firstly by calibrating a relationship between galaxy B-band luminosity and star formation rate, and secondly by a Monte Carlo simulation of a representative sample of galaxies, in which star formation information is randomly sampled from the observed subset. The total star formation rate density of the local Universe is found to be between 0.016 and 0.023 MSun/yr/cubic Mpc, with the uncertainties being dominated by the internal extinction correction used in converting measured H alpha fluxes to star formation rates. If our internally derived B-band luminosity function is replaced by one from the Sloan Digital Sky Survey blue sequence, the star format...

  9. A Time-Series Analysis of the H-alpha Emission Line in V3885 Sagitarii

    Ribeiro, Fabiola M A

    2009-01-01

    Flickering is a phenomenon related to the mass accretion observed among many classes of astrophysical objects. In this paper we present a study of the flickering emission lines and continuum of the Cataclysmic Variable V3885 Sgr. The flickering behavior is first analyzed through statistical analysis and lightcurves power spectra. Autocorrelation techniques are then employed to estimate the flickering flares timescales. A cross correlation study between the line and its underlying continuum variability is presented. The cross correlation between the photometric and spectroscopic data is also discussed. The periodograms, calculated using emission line data, show a behavior that is similar to those obtained from photometric datasets found in the literature, with a plateau at lower frequencies and a power law at higher frequencies. The power law index is consistent with stochastic events. The cross-correlation study indicates the presence of a correlation between the variability on H-alpha and its underlying cont...

  10. Comportamiento de la cromsfera solar en la lnea H-alpha durante el ciclo 23

    Davoli, D.; Aquilano, R.; Missio, H.

    Using the instrumental of the Observatorio Astronmico Municipal de Rosario (OAMR), we analyze the solar chromospheric activity during an approximate period of 11 years. The instrument is a Carl Zeiss refractor telescope of 150 mm aperture and 2250 mm of focal distance with monochromatic filter in the H-alpha line. We take as proxy for the solar activity the area covered by chromospheric plages. Simultaneously, we determine the relative wolf number from observations of the solar photosphere. We describe our technique and the results obtained. We observe 2 maxima of solar activity in the years 2000 and 2001 respectively, and a later decrease of this activity with low average values starting around 2006 that corresponds to the end of cycle 23. FULL TEXT IN SPANISH

  11. The H$\\alpha$ surface brightness $-$ radius plane as a diagnostic tool for photoionized nebulae

    Frew, David J; Parker, Quentin A

    2016-01-01

    The H$\\alpha$ surface brightness $-$ radius ($S-r$) relation is a robust distance indicator for planetary nebulae (PNe), further enhanced by different populations of PNe having distinct loci in $S-r$ space. Other types of photoionized nebulae also plot in quite distinct regions in the $S-r$ plane, allowing its use as a diagnostic tool. In particular, the nova shells and massive star ejecta (MSE) plot on relatively tight loci illustrating their evolutionary sequences. For the MSE, there is potential to develop a distance indicator for these objects, based on their trend in $S-r$ space. As high-resolution, narrowband surveys of the nearest galaxies become more commonplace, the $S-r$ plane is a potentially useful diagnostic tool to help identify the various ionized nebulae in these systems.

  12. Collisionally excited filaments in HST H$\\alpha$ and H$\\beta$ images of HH~1/2

    Raga, A C; Castellanos-Ramrez, A; Chiang, Hsin-Fang; Bally, J

    2014-01-01

    We present new H$\\alpha$ and H$\\beta$ images of the HH~1/2 system, and we find that the H$\\alpha$/H$\\beta$ ratio has high values in ridges along the leading edges of the HH~1 bow shock and of the brighter condensations of HH~2. These ridges have H$\\alpha$/H$\\beta=4\\to 6$, which is consistent with collisional excitation from the $n=1$ to the $n=3$ and 4 levels of hydrogen in a gas of temperatures $T=1.5\\to 10\\times 10^4$~K. This is therefore the first direct proof that the collisional excitation/ionization region of hydrogen right behind Herbig-Haro shock fronts is detected.

  13. An atlas of H-alpha-emitting regions in M33: A systematic search for SS433 star candidates

    Calzetti, Daniela; Kinney, Anne L.; Ford, Holland; Doggett, Jesse; Long, Knox S.

    1995-01-01

    We report finding charts and accurate positions for 432 compact H-alpha emitting regions in the Local Group galaxy M 33 (NGC 598), in an effort to isolate candidates for an SS433-like stellar system. The objects were extracted from narrow band images, centered in the rest-frame H-alpha (lambda 6563 A) and in the red continuum at 6100 A. The atlas is complete down to V approximately equal to 20 and includes 279 compact HII regions and 153 line emitting point-like sources. The point-like sources undoubtedly include a variety of objects: very small HII regions, early type stars with intense stellar winds, and Wolf-Rayet stars, but should also contain objects with the characteristics of SS433. This extensive survey of compact H-alpha regions in M 33 is a first step towards the identification of peculiar stellar systems like SS433 in external galaxies.

  14. H$_{\\alpha}$ line as an indicator of envelope presence around the Cepheid Polaris Aa ($\\alpha~ UMi$)

    Usenko, I A; Klochkova, V G; Tavolzhanskaya, N S

    2015-01-01

    We present the results of the radial velocity ($RV$) measurements of metallic lines as well as H$_{\\alpha}$ (H$_{\\beta}$) obtained in 55 high-resolution spectra of the Cepheid $\\alpha$ UMi (Polaris Aa) in 1994-2010. While the $RV$ amplitudes of these lines are roughly equal, their mean $RV$ begin to differ essentially with growth of the Polaris Aa pulsational activity. This difference is accompanied by the H$_{\\alpha}$ line core asymmetries on the red side mainly (so-called knife-like profiles) and reaches 8-12 km/s in 2003 with a subsequent decrease to 1.5-2 km/s. We interpret a so unusual behaviour of the H$_{\\alpha}$ line core as dynamical changes in the envelope around Polaris Aa.

  15. The critical velocity effect as a cause for the H\\alpha emission from the Magellanic stream

    Konz, C.; Lesch, H.; Birk, G. T.; Wiechen, H.

    2000-01-01

    Observations show significant H\\alpha-emissions in the Galactic halo near the edges of cold gas clouds of the Magellanic Stream. The source for the ionization of the cold gas is still a widely open question. In our paper we discuss the critical velocity effect as a possible explanation for the observed H\\alpha-emission. The critical velocity effect can yield a fast ionization of cold gas if this neutral gas passes through a magnetized plasma under suitable conditions. We show that for paramet...

  16. The critical velocity effect as a cause for the H\\alpha emission from the Magellanic stream

    Konz, C; Birk, G T; Wiechen, H

    2001-01-01

    Observations show significant H\\alpha-emissions in the Galactic halo near the edges of cold gas clouds of the Magellanic Stream. The source for the ionization of the cold gas is still a widely open question. In our paper we discuss the critical velocity effect as a possible explanation for the observed H\\alpha-emission. The critical velocity effect can yield a fast ionization of cold gas if this neutral gas passes through a magnetized plasma under suitable conditions. We show that for parameters that are typical for the Magellanic Stream the critical velocity effect has to be considered as a possible ionization source of high relevance.

  17. The Wyoming Survey for H-alpha. I. Initial Results at z ~ 0.16 and 0.24

    Dale, Daniel A.; Barlow, Rebecca J.; Cohen, Seth A.; Johnson, L. Clifton; Kattner, ShiAnne M.; Lamanna, Christine A.; Moore, Carolynn A.; Schuster, Micah D.; Thatcher, Jacob W.

    2008-01-01

    The Wyoming Survey for H-alpha, or WySH, is a large-area, ground-based, narrowband imaging survey for H-alpha-emitting galaxies over the latter half of the age of the Universe. The survey spans several square degrees in a set of fields of low Galactic cirrus emission. The observing program focuses on multiple dz~0.02 epochs from z~0.16 to z~0.81 down to a uniform (continuum+line) luminosity at each epoch of ~10^33 W uncorrected for extinction (3sigma for a 3" diameter aperture). First results...

  18. FIRST SIMULTANEOUS OBSERVATION OF AN H{alpha} MORETON WAVE, EUV WAVE, AND FILAMENT/PROMINENCE OSCILLATIONS

    Asai, Ayumi; Isobe, Hiroaki [Unit of Synergetic Studies for Space, Kyoto University, Yamashina, Kyoto 607-8471 (Japan); Ishii, Takako T.; Kitai, Reizaburo; Ichimoto, Kiyoshi; UeNo, Satoru; Nagata, Shin' ichi; Morita, Satoshi; Nishida, Keisuke; Shibata, Kazunari [Kwasan and Hida Observatories, Kyoto University, Yamashina, Kyoto 607-8471 (Japan); Shiota, Daikou [Advanced Science Institute, RIKEN, Wako, Saitama 351-0198 (Japan); Oi, Akihito [College of Science, Ibaraki University, Mito, Ibaraki 310-8512 (Japan); Akioka, Maki, E-mail: asai@kwasan.kyoto-u.ac.jp [Hiraiso Solar Observatory, National Institute of Information and Communications Technology, Hitachinaka, Ibaraki 311-1202 (Japan)

    2012-02-15

    We report on the first simultaneous observation of an H{alpha} Moreton wave, the corresponding EUV fast coronal waves, and a slow and bright EUV wave (typical EIT wave). We observed a Moreton wave, associated with an X6.9 flare that occurred on 2011 August 9 at the active region NOAA 11263, in the H{alpha} images taken by the Solar Magnetic Activity Research Telescope at Hida Observatory of Kyoto University. In the EUV images obtained by the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory we found not only the corresponding EUV fast 'bright' coronal wave, but also the EUV fast 'faint' wave that is not associated with the H{alpha} Moreton wave. We also found a slow EUV wave, which corresponds to a typical EIT wave. Furthermore, we observed, for the first time, the oscillations of a prominence and a filament, simultaneously, both in the H{alpha} and EUV images. To trigger the oscillations by the flare-associated coronal disturbance, we expect a coronal wave as fast as the fast-mode MHD wave with the velocity of about 570-800 km s{sup -1}. These velocities are consistent with those of the observed Moreton wave and the EUV fast coronal wave.

  19. Nature of H-alpha selected galaxies at z>2. I. Main sequence and dusty star-forming galaxies

    Tadaki, Ken-ichi; Tanaka, Ichi; Hayashi, Masao; Koyama, Yusei; Shimakawa, Rhythm

    2013-01-01

    We present the results from our narrow-band imaging surveys of HAEs at z=2.2 and z=2.5 in the Subaru/XMM-Newton Deep survey Field with near-infrared camera MOIRCS on Subaru Telescope. We have constructed a clean sample of 63 star-forming galaxies at z=2.2 and 46 at z=2.5. For 12 (or ~92%) out of 13 H\\alpha emitters (HAEs) at z=2.2, their H\\alpha emission lines have been successfully detected by the spectroscopy. While about 42% of the red, massive HAEs with M_*>10^{10.8} M_\\odot contain AGNs, most of the blue, less massive ones are likely to be star-forming galaxies. This suggests that the AGN may play an important role in galaxy evolution at the late stage of truncation. For the HAEs excluding possible AGNs, we estimate the gas-phase metallicities on the basis of [N~{\\sc ii}]/H\\alpha ratios, and find that the metallicities of the H\\alpha selected galaxies at z=2.2 are lower than those of local star-forming galaxies at fixed stellar mass, as shown by previous studies. Moreover, we present and discuss the so-c...

  20. Detection of H-alpha emission from z>3.5 submillimetre luminous galaxies with AKARI-FUHYU spectroscopy

    Sedgwick, Chris; Pearson, Chris; Smail, Ian; Im, Myungshin; Oyabu, Shinki; Takagi, Toshinobu; Matsuhara, Hideo; Wada, Takehiko; Lee, Hyung Mok; Jeong, Woong-Seob; White, Glenn J

    2013-01-01

    We present tentative H-alpha emission line detections of four submillimetre-detected galaxies at z>3.5: the radio galaxies 8C1909+722 and 4C60.07 at signal-to-noise ratios (SNRs) of 3.1 and 2.5, and two submillimetre-selected galaxies (SMGs) near the first of these at SNRs of 10.0 and 2.4, made with the AKARI Space Telescope as part of the FUHYU mission program. These are the highest-redshift H-alpha detections in such galaxies, made possible by AKARI's unique near-infrared spectroscopic capability. The two radio galaxies had known redshifts and surrounding structure, and we have detected broad H-alpha components indicating the presence of dust-shrouded quasars. We conclude that powerful AGNs at z>3.5 occur in peaks of the star-formation density fields, supporting a close connection between stellar mass build-up and black hole mass assembly at this redshift. We also show that 4C60.07 is a binary AGN. The H-alpha detections of the two SMGs are the first redshift determinations for these sources, confirming the...

  1. H$\\alpha$ spectroscopy and multi-wavelength imaging of a solar flare caused by filament eruption

    Huang, Z; Koleva, K; Doyle, J G; Duchlev, P; Dechev, M; Reardon, K

    2014-01-01

    We study a sequence of eruptive events including filament eruption, a GOES C4.3 flare and a coronal mass ejection. We aim to identify the possible trigger(s) and precursor(s) of the filament destabilisation; investigate flare kernel characteristics; flare ribbons/kernels formation and evolution; study the interrelation of the filament-eruption/flare/coronal-mass-ejection phenomena as part of the integral active-region magnetic field configuration; determine H alpha line profile evolution during the eruptive phenomena. Multi-instrument observations are analysed including H$\\alpha$ line profiles, speckle images at H$\\alpha$-0.8 \\AA\\ and H$\\alpha$+0.8 \\AA\\ from IBIS at DST/NSO, EUV images and magnetograms from the SDO, coronagraph images from STEREO and the X-ray flux observations from FERMI and GOES. We establish that the filament destabilisation and eruption are the main trigger for the flaring activity. A surge-like event with a circular ribbon in one of the filament footpoints is determined as the possible t...

  2. Discovery of H-alpha Emission from the Close Companion Inside the Gap of Transitional Disk HD142527

    Close, L M; Males, J R; Puglisi, A; Xompero, M; Apai, D; Najita, J; Weinberger, A J; Morzinski, K; Rodigas, T J; Hinz, P; Bailey, V; Briguglio, R

    2014-01-01

    We utilized the new high-order 585 actuator Magellan Adaptive Optics system (MagAO) to obtain very high-resolution visible light images of HD142527 with MagAO's VisAO science camera. In the median seeing conditions of the 6.5m Magellan telescope (0.5-0.7"), we find MagAO delivers 24-19% Strehl at H-alpha (0.656 microns). We detect a faint companion (HD142527B) embedded in this young transitional disk system at just 86.3+/-1.9 mas (~12 AU) from the star. The companion is detected in both H-alpha and a continuum filter (Delta_mag=6.33+/-0.20 mag at H-alpha and 7.50+/-0.25 mag in the continuum filter). This provides confirmation of the tentative companion discovered by Biller and co-workers with sparse aperture masking at the 8m VLT. The H-alpha emission from the ~0.25 solar mass companion (EW=180 Angstroms) implies a mass accretion rate of ~5.9x10^-10 Msun/yr, and a total accretion luminosity of 1.2% Lsun. Assuming a similar accretion rate, we estimate that a 1 Jupiter mass gas giant could have considerably bet...

  3. Discovery of an Apparent Nova in M81 and H-alpha Confirmation of Three M81 Nova Candidates

    Hornoch, K.; Vaduvescu, O.; Tudor, V.

    2014-06-01

    We report the discovery of an apparent nova in M81 on a co-added 2000-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma under ~1.6" seeing on 2014 Jun. ...

  4. Strong H-alpha Emission Detected in the M33 Nova Candidate PNV J01340288+3035111

    Hornoch, K.; Vaduvescu, O.; Tudor, V.

    2014-07-01

    We obtained four 240-s narrow-band H-alpha and four 120-s R-band CCD frames of M33 on 2014 July 29.206 and 29.222 UT, respectively, with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma under ~1.1" seeing.

  5. Comparison of H-alpha synoptic charts with the large-scale solar magnetic field as observed at Stanford

    Duvall, T. L., Jr.; Wilcox, J. M.; Svalgaard, L.; Scherrer, P. H.; Mcintosh, P. S.

    1977-01-01

    Two methods of observing the neutral line of the large-scale photospheric magnetic field are compared: neutral line positions inferred from H-alpha photographs (McIntosh and Nolte, 1975) and observations of the photospheric magnetic field made with low spatial resolution (three minutes) and high sensitivity using the Stanford magnetograph. The comparison is found to be very favorable.

  6. H-alpha survey of low-mass satellites of the neighbouring galaxies M31 and M81

    Kaisin, S S

    2013-01-01

    Images have been obtained at the 6-m telescope at the Special Astrophysical Observatory (SAO) of the Russian Academy of Sciences in the H-alpha line and in the continuum for 20 dwarf spheroidal satellites of M31: And XI-And XXX, plus the distant Globular cluster Bol 520. Their star formation rates (FR) are estimated using the H-alpha flux and the ultraviolet FUV flux measured with the GALEX space telescope. Most of the dSph satellites of M31 have extremely low star formation rates with a characteristic upper limit of SFR~5x10^{-7}. We have made similar estimates of SFR from the H-alpha and FUV fluxes for 13 galaxies with low surface brightness recently discovered in the neighborhood of M81. Eleven of them are physical satellites of M81 with typical SFR< 5x10^{-5}. The median stellar masses of these satellites of M31 and M81 are 0.9 and 1.9 million solar masses, respectively. Our H-alpha observations place a 2-3 times stricter limit on the value of SFR than the data from the GALEX satellite, with a substant...

  7. Evidence of Planetesimal infall on to the very young Herbig Be star LkH$_\\alpha$234

    Chakraborty, A; Mahadevan, S

    2004-01-01

    We report here the first evidence for planetesimal infall onto the very young Herbig Be star LkH$_\\alpha$234. These results are based on observations acquired over 31 days using spectroscopy of the sodium D lines, the He I 5876\\AA, and hydrogen H$_\\alpha$ lines. We find Redshifted Absorption Components (RAC) with velocities up to 200 km/s and very mild Blueshifted Absorption Components (BEC) up to 100 km/s in the Na I lines. No correlation is observed between the appearance of the Na I RAC & BEC and the H$_\\alpha$ and He I line variability, which suggests that these (Na I RAC & BEC) are formed in a process unrelated to the circumstellar gas accretion. We interpret the Na I RAC as evidence for an infalling evaporating body, greater than 100 km in diameter, which is able to survive at distances between 2.0 to 0.1 AU from the star. The dramatic appearance of the sodium RAC and mild BEC is readily explained by the dynamics of this infalling body making LkH$_\\alpha$234 the youngest (age $\\sim$ 0.1 Myr) sys...

  8. Investigating H$\\alpha$, UV, and IR star-formation rate diagnostics for a large sample of z ~ 2 galaxies

    Shivaei, Irene; Steidel, Charles C; Shapley, Alice E

    2015-01-01

    We use a sample of 262 spectroscopically confirmed star-forming galaxies at redshifts $2.08\\leq z\\leq 2.51$ to compare H$\\alpha$, UV, and IR star-formation-rate diagnostics and to investigate the dust properties of the galaxies. At these redshifts, the H$\\alpha$ line shifts to the $K_{s}$-band. By comparing $K_{s}$-band photometry to underlying stellar population model fits to other UV, optical, and near-infrared data, we infer the H$\\alpha$ flux for each galaxy. We obtain the best agreement between H$\\alpha$- and UV-based SFRs if we assume that the ionized gas and stellar continuum are reddened by the same value and that the Calzetti attenuation curve is applied to both. Aided with MIPS 24$\\mu$m data, we find that an attenuation curve steeper than the Calzetti curve is needed to reproduce the observed IR/UV ratios of galaxies younger than 100 Myr. Furthermore, using the bolometric star-formation rate inferred from the UV and mid-IR data (SFR$_{IR}$+SFR$_{UV}$), we calculated the conversion between the H$\\alp...

  9. FUNDPAR: A program for Deriving Fundamental Parameters from Equivalent Widths

    C. Saffe

    2011-01-01

    Full Text Available Implementamos un programa en Fortran que determina parámetros fundamentales de estrellas de tipo solar, a partir de anchos equivalentes del Fe. La solución debe verificar tres condiciones en el método estándar: equilibrio de ionización, equilibrio de excitación e independencia entre abundancias y anchos equivalentes. Calculamos modelos de atmósfera de Kurucz con opacidades NEWODF. Detalles como el parámetro de longitud de mezcla, el sobre impulso convectivo, etc. se calculan con un programa independiente. FUNDPAR calcula las incertezas por dos métodos: el criterio de Gonzalez & Vanture (1998 y utilizando la función X² . Los resultados derivados con FUNDPAR están de acuerdo con determinaciones previas en la literatura. En particular obtuvimos parámetros fundamentales de 58 estrellas con exoplanetas. El programa está disponible en la red1.

  10. Graphs of Small Rank-width are Pivot-minors of Graphs of Small Tree-width

    Kwon, O-joung

    2012-01-01

    We prove that every graph of rank-width $k$ is a pivot-minor of a graph of tree-width at most $2k$. We also prove that graphs of rank-width at most 1, equivalently distance-hereditary graphs, are exactly vertex-minors of trees, and graphs of linear rank-width at most 1 are precisely vertex-minors of paths. In addition, we show that bipartite graphs of rank-width at most 1 are exactly pivot-minors of trees and bipartite graphs of linear rank-width at most 1 are precisely pivot-minors of paths.

  11. The KPNO International Spectroscopic Survey. V. H-alpha-selected Survey List 3

    Jangren, A; Sarajedini, V L; Gronwall, C; Werk, J K; Chomiuk, L; Moody, J W; Boroson, T A; Jangren, Anna; Salzer, John J.; Sarajedini, Vicki L.; Gronwall, Caryl; Werk, Jessica K.; Chomiuk, Laura; Boroson, Todd A.

    2005-01-01

    The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey designed to detect extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors, and is the first purely digital objective-prism survey for emission-line galaxies (ELGs). Here we present the third list of ELG candidates selected from our red spectral data, which cover the wavelength range 6400 to 7200 A. In most cases, the detected emission line is H-alpha. The current survey list covers the region of the NOAO Deep Wide-Field Survey (NDWFS). This survey covers two fields; the first is 3 x 3 degrees square and located at RA = 14h 30m, DEC = 34.5 deg (B1950), the second is 2.3 x 4.0 degrees and centered at RA = 2h 7.5m, DEC = -4.75 deg. A total area of 19.65 deg^2 is covered by the KISS data. A total of 261 candidate emission-line objects have been selected for inclusion in the survey list (13.3 per deg^2). We tabulate accurate coordinate...

  12. The H$\\alpha$ kinematics of interacting galaxies in 12 compact groups

    Torres-Flores, S; de Oliveira, C Mendes; Plana, H; Balkowski, C; Marcelin, M; Olave-Rojas, D

    2014-01-01

    We present new Fabry-Perot observations for a sample of 42 galaxies located in twelve compact groups of galaxies: HCG 1, HCG 14, HCG 25, HCG 44, HCG 53, HCG 57, HCG 61, HCG 69, HCG 93, VV 304, LGG 455 and Arp 314. From the 42 observed galaxies, a total of 26 objects are spiral galaxies, which range from Sa to Im morphological types. The remaining 16 objects are E, S0 and S0a galaxies. Using these observations, we have derived velocity maps, monochromatic and velocity dispersion maps for 24 galaxies, where 18 are spiral, three are S0a, two are S0 and one is an Im galaxy. From the 24 velocity fields obtained, we could derive rotation curves for 15 galaxies; only two of them exhibit rotation curves without any clear signature of interactions. Based on kinematic information, we have evaluated the evolutionary stage of the different groups of the current sample. We identify groups that range from having no H$\\alpha$ emission to displaying an extremely complex kinematics, where their members display strongly pertur...

  13. Proper Motions of H-alpha filaments in the Supernova Remnant RCW 86

    Helder, E A; Bamba, A; Bleeker, J A M; Burrows, D N; Ghavamian, P; Yamazaki, R

    2013-01-01

    We present a proper motion study of the eastern shock-region of the supernova remnant RCW 86 (MSH 14-63, G315.4-2.3), based on optical observations carried out with VLT/FORS2 in 2007 and 2010. For both the northeastern and southeastern regions, we measure an average proper motion of H-alpha filaments of 0.10 +/- 0.02 arcsec/yr, corresponding to 1200 +/- 200 km/s at 2.5kpc. There is substantial variation in the derived proper motions, indicating shock velocities ranging from just below 700 km/s to above 2200 km/s. The optical proper motion is lower than the previously measured X-ray proper motion of northeastern region. The new measurements are consistent with the previously measured proton temperature of 2.3 +/- 0.3 keV, assuming no cosmic-ray acceleration. However, within the uncertainties, moderately efficient (< 27 per cent) shock acceleration is still possible. The combination of optical proper motion and proton temperature rule out the possibility that RCW 86 has a distance less than 1.5kpc. The simil...

  14. Improved measurement of (3)J(H(alpha)(i),N(i+1)) coupling constants in H(2)O dissolved proteins.

    Löhr, F; Schmidt, J M; Maurer, S; Rüterjans, H

    2001-11-01

    A modification to the recently proposed alpha/beta-HN(CO)CA-J TROSY pulse sequence (P. Permi et al., J. Magn. Reson. 146, 255-259 (2000)) makes it possible to determine (3)J(H(alpha)(i), N(i+1)) coupling constants from a single E.COSY-type cross-peak pattern rather than from two (1)H(alpha) spin-state-edited subspectra. Advantages are increased (15)N resolution, critical to extracting accurate (1)H(alpha)-(15)N coupling constants, and minimized differential relaxation due to nested (13)C(alpha) and (15)N evolution periods. Application of the improved pulse sequence to Desulfovibrio vulgaris flavodoxin results in (3)J(H(alpha)(i), N(i+1)) values being systematically larger than those obtained with the original scheme. Parametrization of the coupling dependence on the protein backbone torsion angle psi yields the Karplus relation (3)J(H(alpha)(i), N(i+1))=-1.00 cos(2)(psi-120 degrees )+0.65 cos(psi-120 degrees )-0.15 Hz, with a residual root-mean-square difference of 0.13 Hz between measured and back-calculated coupling constants. The curve compares with data derived from ubiquitin (A. C. Wang and A. Bax, J. Am. Chem. Soc. 117, 1810-1813 (1995)), although spanning a slightly larger range of J values in flavodoxin. The orientation of the Ala39/Ser40 peptide link, forming a type-II beta-turn in flavodoxin, is twisted against X-ray-derived torsions by approximately 10 degrees in the NMR structure as evident from the analysis of straight phi- and psi-related (3)J coupling constants. The remaining deviation of some experimental values from the prediction is likely to be due to strong hydrogen bonding, substituent effects, or the additional dependence on the adjacent torsions straight phi. PMID:11700083

  15. Relative Strengths of Raman Scattered He II 6545 and H alpha Wings In the Symbiotic Star V1016 Cyg and the Young Planetary Nebulae IC 5117

    Lee, H.-W.; Kang, Suna

    2006-08-01

    Many symbiotic stars and some young planetary nebulae are known to exhibit very prominent and broad wings around H alpha emission. Lee (2000) proposed that these H alpha wings are formed from Raman scattering by atomic hydrogen of far UV radiation around Ly beta. However, broad wings may also arise from other mechanisms including fast gas flows around the hot star and Thomson scattering. Furthermore, it is unclear whether continuum around Ly beta or Ly beta line photons themselves are responsible for the broad H alpha wings in the proposal of Lee (2000). In order to confirm the Raman scattering origin of H alpha wings, we present our high resolution spectrum around H alpha of the symbiotic star V1016 Cyg and the young planetary nebula IC 5117 obtained with the Bohyunsan Optical Echelle Spectrograph installed on the 1.8m telescope. The two objects show relatively strong Raman scattered He II 6545 features but H alpha wings are significantly weak in IC 5117 compared with those in V1016 Cyg. In the spectra, we note that the H alpha and He II emission lines in IC 5117 are much narrower than the counterparts in V1016 Cyg. Applying Gaussian fits to these emission lines and inferring the far UV radiation compatible with the recombination theory, we perform Monte Carlo simulations of Raman scattered He II 6545 and H alpha wings in an assumed neutral region with H I column density of 10^22 cm^-2. Our numerical results show relatively weak H alpha wings compared with He II 6545 in IC 5117 and quite strong H alpha wings in V 1016 Cyg, which is consistent with our observational spectra. This result strongly indicates that the broad H alpha wings are originated from the Ly beta line photons not continuum photons around Ly beta.

  16. The most luminous H$\\alpha$ emitters at z~0.8-2.23 from HiZELS: evolution of AGN and star-forming galaxies

    Sobral, David; Best, Philip N; Smail, Ian; Harrison, Chris M; Stott, John; Calhau, João; Matthee, Jorryt

    2016-01-01

    We use new near-infrared spectroscopic observations to investigate the nature and evolution of the most luminous H\\alpha (Ha) emitters at z~0.8-2.23, which evolve strongly in number density over this period, and compare them to more typical Ha emitters. We study 59 luminous Ha emitters with $L_{H\\alpha}>L_{H\\alpha}^*$, roughly equally split per redshift slice at z~0.8, 1.47 and 2.23 from the HiZELS and CF-HiZELS surveys. We find that, overall, 30$\\pm$8% are AGN (80$\\pm$30% of these AGN are broad-line AGN, BL-AGN), and we find little to no evolution in the AGN fraction with redshift, within the errors. However, the AGN fraction increases strongly with Ha luminosity and correlates best with $L_{H\\alpha}/L_{H\\alpha}^*(z)$. While $L_{H\\alpha}80%), the most luminous Ha emitters ($L_{H\\alpha}>10L_{H\\alpha}^*(z)$) at any cosmic time are essentially all BL-AGN. Using our AGN-decontaminated sample of luminous star-forming galaxies, and integrating down to a fixed Ha luminosity, we find a factor of ~1300x evolution in ...

  17. High specific activity N-Acetyl-3{sup H}-{alpha}-Aspartyl- L-Glutamic at micro mole scale; Sintesis de N-Acetil-3{sup H}- {alpha} -Aspartil-Glutamico a escala de Micromoles

    Suarez, C.

    1984-07-01

    High specific activity N-Acetyl-3{sup H}- {alpha} -Aspartyl-I-Glutamic acid at micro mole scale in prepared acetylating L- {alpha} -Aspartyl-L-glutamic with 3{sup H}-acetic anhydride in re distilled toluene. The product le purified through cationic and anionic columns. The radiochemical purity as determined by thin-layer chromatography is greater then 99% at the time preparation. (Author) 5 refs.

  18. A high-speed digital camera system for the observation of rapid H-alpha fluctuations in solar flares

    Kiplinger, Alan L.; Dennis, Brian R.; Orwig, Larry E.

    1989-01-01

    Researchers developed a prototype digital camera system for obtaining H-alpha images of solar flares with 0.1 s time resolution. They intend to operate this system in conjunction with SMM's Hard X Ray Burst Spectrometer, with x ray instruments which will be available on the Gamma Ray Observatory and eventually with the Gamma Ray Imaging Device (GRID), and with the High Resolution Gamma-Ray and Hard X Ray Spectrometer (HIREGS) which are being developed for the Max '91 program. The digital camera has recently proven to be successful as a one camera system operating in the blue wing of H-alpha during the first Max '91 campaign. Construction and procurement of a second and possibly a third camera for simultaneous observations at other wavelengths are underway as are analyses of the campaign data.

  19. Evidence of Environmental Dependencies of Type Ia Supernovae from the Nearby Supernova Factory indicated by Local H{\\alpha}

    Rigault, M; Aldering, G; Antilogus, P; Aragon, C; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Cellier-Holzem, F; Childress, M; Chotard, N; Fakhouri, H K; Feindt, U; Fleury, M; Gangler, E; Greskovic, P; Guy, J; Kim, A G; Kowalski, M; Lombardo, S; Nordin, J; Nugent, P; Pain, R; Pécontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Runge, K; Saunders, C; Scalzo, R; Smadja, G; Tao, C; Thomas, R C; Weaver, B A

    2013-01-01

    (Abridged) We study the host galaxy regions in close proximity to Type Ia supernovae (SNe Ia) to analyze relations between the properties of SN Ia events and environments most similar to where their progenitors formed. We focus on local H\\alpha\\ emission as an indicator of young environments. The Nearby Supernova Factory has obtained flux-calibrated spectral timeseries for SNe Ia using integral field spectroscopy, allowing the simultaneous measurement of the SN and its immediate vicinity. For 89 SNe Ia we measure H\\alpha\\ emission tracing ongoing star formation within a 1 kpc radius around each SN. This constitutes the first direct study of the local environment for a large sample of SNe Ia also having accurate luminosity, color and stretch measurements. We find that SNe Ia with local H\\alpha\\ emission are redder by 0.036+/-0.017 mag, and that the previously-noted correlation between stretch and host mass is entirely driven by the SNe Ia coming from passive regions. Most importantly, the mean standardized bri...

  20. HIGH RESOLUTION H{alpha} IMAGES OF THE BINARY LOW-MASS PROPLYD LV 1 WITH THE MAGELLAN AO SYSTEM

    Wu, Y.-L.; Close, L. M.; Males, J. R.; Follette, K.; Morzinski, K.; Kopon, D.; Rodigas, T. J.; Hinz, P. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Puglisi, A.; Esposito, S.; Pinna, E.; Riccardi, A.; Xompero, M.; Briguglio, R., E-mail: yalinwu@email.arizona.edu [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy)

    2013-09-01

    We utilize the new Magellan adaptive optics system (MagAO) to image the binary proplyd LV 1 in the Orion Trapezium at H{alpha}. This is among the first AO results in visible wavelengths. The H{alpha} image clearly shows the ionization fronts, the interproplyd shell, and the cometary tails. Our astrometric measurements find no significant relative motion between components over {approx}18 yr, implying that LV 1 is a low-mass system. We also analyze Large Binocular Telescope AO observations, and find a point source which may be the embedded protostar's photosphere in the continuum. Converting the H magnitudes to mass, we show that the LV 1 binary may consist of one very-low-mass star with a likely brown dwarf secondary, or even plausibly a double brown dwarf. Finally, the magnetopause of the minor proplyd is estimated to have a radius of 110 AU, consistent with the location of the bow shock seen in H{alpha}.

  1. Dust attenuation in z $\\sim$ 1 galaxies from Herschel and 3D-HST H$\\alpha$ measurements

    Puglisi, A; Franceschini, A; Talia, M; Cimatti, A; Baronchelli, I; Daddi, E; Renzini, A; Schawinski, K; Mancini, C; Silverman, J; Gruppioni, C; Lutz, D; Berta, S; Oliver, S J

    2015-01-01

    We combined the spectroscopic information from the 3D-HST survey with the PEP/Herschel data to characterize the H\\alpha dust attenuation properties of a sample of 79 normal star-forming galaxies at $0.7\\leq z\\leq1.5$ in the GOODS-S field. The sample was selected in the far-IR, at \\lambda=100 and/or 160 \\mu m, and only includes galaxies with a secure H\\alpha detection (S/N>3). From the low resolution 3D-HST spectra we measured z and F(H\\alpha) for the whole sample, rescaling the observed flux by a constant factor of 1.2 to remove the contamination by [NII]. The stellar masses, infrared and UV luminosities were derived from the SEDs by fitting multi-band data from GALEX near-UV to SPIRE500 \\mu m. We derived the continuum extinction Estar(B-V) from both the IRX ratio and the UV-slope, and found an excellent agreement among them. Galaxies in the sample have 2.6x10^9$\\leq$M*$\\leq$3.5x10^11 Msun, intense infrared luminosity (L_IR>1.2x10^10 Lsun), high level of dust obscuration (0.1$\\leq$Estar(B-V)$\\leq$1.1) and str...

  2. Nature of H-alpha selected galaxies at z>2. II. Clumpy galaxies and compact star-forming galaxies

    Tadaki, Ken-ichi; Tanaka, Ichi; Hayashi, Masao; Koyama, Yusei; Shimakawa, Rhythm

    2013-01-01

    We present the morphological properties of 109 H\\alpha-selected galaxies at z>2 in SXDF-UDS-CANDELS field. With high-resolution optical/near-infrared images obtained by Hubble Space Telescope, we identify giant clumps within the H\\alpha emitters (HAEs). We find that at least 41% of our sample show clumpy structures in the underlying disks. The color gradient of clumps is commonly seen in the sense that the clumps near the galactic center tend to be redder than those in the outer regions. The mid-infrared detection in galaxies with red clumps and the spatial distribution of H\\alpha emission suggest that dusty star-formation activity is probably occurring in the nuclear red clumps. A gas supply to a bulge component through the clump migration is one of the most potent physical processes to produce such dusty star-forming clumps and form massive bulges in local early-type galaxies. They would become large quiescent galaxies at later times just by consumption or blowout of remaining gas. Also, while most of the H...

  3. The Second Data Release of the INT Photometric H\\alpha\\ Survey of the Northern Galactic Plane (IPHAS DR2)

    Barentsen, Geert; Drew, J E; González-Solares, E A; Greimel, R; Irwin, M J; Miszalski, B; Ruhland, C; Groot, P; Mampaso, A; Sale, S E; Henden, A A; Aungwerojwit, A; Barlow, M J; Carter, P J; Corradi, R L M; Drake, J J; Eislöffel, J; Fabregat, J; Gänsicke, B T; Fusillo, N P Gentile; Greiss, S; Hales, A S; Hodgkin, S; Huckvale, L; Irwin, J; King, R; Knigge, C; Kupfer, T; Lagadec, E; Lennon, D J; Lewis, J R; Mohr-Smith, M; Morris, R A H; Naylor, T; Parker, Q A; Phillipps, S; Pyrzas, S; Raddi, R; Roelofs, G H A; Rodríguez-Gil, P; Sabin, L; Scaringi, S; Steeghs, D; Suso, J; Tata, R; Unruh, Y C; van Roestel, J; Viironen, K; Vink, J S; Walton, N A; Wright, N J; Zijlstra, A A

    2014-01-01

    The INT/WFC Photometric H-Alpha Survey of the Northern Galactic Plane (IPHAS) is a 1800 square degrees imaging survey covering Galactic latitudes |b| < 5 deg and longitudes l = 30 to 215 deg in the r, i and H\\alpha\\ filters using the Wide Field Camera (WFC) on the 2.5-metre Isaac Newton Telescope (INT) in La Palma. We present the first quality-controlled and globally-calibrated source catalogue derived from the survey, providing single-epoch photometry for 219 million unique sources across 92% of the footprint. The observations were carried out between 2003 and 2012 at a median seeing of 1.1 arcsec (sampled at 0.33 arcsec/pixel) and to a mean 5\\sigma-depth of 21.2 (r), 20.0 (i) and 20.3 (H\\alpha) in the Vega magnitude system. We explain the data reduction and quality control procedures, describe and test the global re-calibration, and detail the construction of the new catalogue. We show that the new calibration is accurate to 0.03 mag (rms) and recommend a series of quality criteria to select the most rel...

  4. Stellar Populations and the Star Formation Histories of LSB Galaxies: I. Optical and H-alpha Imaging

    Schombert, James; McGaugh, Stacy

    2011-01-01

    This paper presents optical and H-alpha imaging for a large sample of LSB galaxies selected from the PSS-II catalogs (Schombert et. al 1992). As noted in previous work, LSB galaxies span a range of luminosities (-10 > M_V > -20) and sizes (0.3 kpc < R_V25 < 10 kpc), although they are consistent in their irregular morphology. Their H-alpha luminosities (L(H-alpha) range from 10^36 to 10^41 ergs s^-1 (corresponding to a range in star formation, using canonical prescriptions, from 10^-5 to 1 M_solar yr^-1). Although their optical colors are at the extreme blue edge for galaxies, they are similar to the colors of dwarf galaxies (van Zee 2001) and gas-rich irregulars (Hunter & Elmegreen 2006). However, their star formation rates per unit stellar mass are a factor of ten less than other galaxies of the same baryonic mass, indicating that they are not simply quiescent versions of more active star forming galaxies. This paper presents the data, reduction techniques and new philosophy of data storage and pre...

  5. A catalogue of early-type emission-line stars and H{\\alpha} line profiles from LAMOST DR2

    Hou, Wen; Hu, Jingyao; Yang, Haifeng; Du, Changde; Liu, Chao; Lee, Chien-De; Lin, Chien-Cheng; Wang, Yuefei; Zhang, Yong; Cao, Zihuang; Hou, Yonghui

    2016-01-01

    We present a catalogue including 11,204 spectra for 10,436 early-type emission-line stars from LAMOST DR2, among which 9,752 early-type emission-line spectra are newly discovered. For these early-type emission-line stars, we discuss the morphological and physical properties from their low-resolution spectra. In this spectral sample, the H$\\alpha$ emission profiles display a wide variety of shapes. Based on the H$\\alpha$ line profiles, these spectra are categorized into five distinct classes: single-peak emission, single-peak emission in absorption, double-peak emission, double-peak emission in absorption, and P-Cygni profiles. To better understand what causes the H$\\alpha$ line profiles, we divide these objects into four types from the view of physical classification, which include classical Be stars, Herbig Ae/Be stars, close binaries and spectra contaminated by HII regions. The majority of Herbig Ae/Be stars and classical Be stars are identified and separated using the (H-K, K-W1) color-color diagram. We al...

  6. The Wyoming Survey for H-alpha. I. Initial Results at z ~ 0.16 and 0.24

    Dale, Daniel A; Cohen, Seth A; Johnson, L Clifton; Kattner, ShiAnne M; Lamanna, Christine A; Moore, Carolynn A; Schuster, Micah D; Thatcher, Jacob W

    2008-01-01

    The Wyoming Survey for H-alpha, or WySH, is a large-area, ground-based, narrowband imaging survey for H-alpha-emitting galaxies over the latter half of the age of the Universe. The survey spans several square degrees in a set of fields of low Galactic cirrus emission. The observing program focuses on multiple dz~0.02 epochs from z~0.16 to z~0.81 down to a uniform (continuum+line) luminosity at each epoch of ~10^33 W uncorrected for extinction (3sigma for a 3" diameter aperture). First results are presented here for 98+208 galaxies observed over approximately 2 square degrees at redshifts z~0.16 and 0.24, including preliminary luminosity functions at these two epochs. These data clearly show an evolution with lookback time in the volume-averaged cosmic star formation rate. Integrals of Schechter fits to the extinction-corrected H-alpha luminosity functions indicate star formation rates per co-moving volume of 0.009 and 0.014 h_70 M_sun/yr/Mpc^3 at z~0.16 and 0.24, respectively. The formal uncertainties in the ...

  7. Integral Field Spectroscopy based H\\alpha\\ sizes of local Luminous and Ultraluminous Infrared Galaxies. A Direct Comparison with high-z Massive Star Forming Galaxies

    Arribas, S; Alonso-Herrero, A; Rosales-Ortega, F F; Monreal-Ibero, A; García-Marín, M; García-Burillo, S; Rodríguez-Zaurín, J

    2012-01-01

    Aims. We study the analogy between local U/LIRGs and high-z massive SFGs by comparing basic H{\\alpha} structural characteristics, like size, luminosity and Star Formation Rate (SFR) surface density, in an homogeneous way (i.e. same tracer and size definition, similar physical scales). Methods. We use Integral Field Spectroscopy based H{\\alpha} emission maps for a representative sample of 54 local U/LIRGs (66 galaxies). From this initial sample we select 26 objects with H{\\alpha} luminosities (L(H{\\alpha})) similar to those of massive (i.e. M\\ast \\sim 10^10 M\\odot or larger) SFGs at z \\sim 2, and probing similar physical scales. Results. The sizes of the H{\\alpha} emitting region in the sample of local U/LIRGs span a large range, with r1/2(H{\\alpha}) from 0.2 to 7 kpc. However, about 2/3 of local U/LIRGs with Lir > 10^11.4 L\\odot have compact H{\\alpha} emission (i.e. r1/2 2 kpc). These are systems showing pre-coalescence merger activity and they are indistinguishable from the massive high-z SFGs galaxies in t...

  8. Resonances and resonance widths

    Two-dimensional betatron resonances are much more important than their simple one-dimensional counterparts and exhibit a strong dependence on the betatron phase advance per cell. A practical definition of ''width'' is expanded upon in order to display these relations in tables. A primarily pedagogical introduction is given to explain the tables, and also to encourage a wider capability for deriving resonance behavior and wider use of ''designer'' resonances

  9. Equivalent Equilibria.

    Kandori, Michihiro

    1988-01-01

    This paper provides a way to formulate a general equilibrium model with both infinite time horizon and continuous uncertainty by 2.space, and provides a si mple proof of the equiva-lence of equilibria in complete markets, inc omplete markets with sequential trading, and incomplete markets with one-shot trades in single consumer economies. The proof is general in the sense that it does not assume time-homogeneous structure nor smo othness of preferences. The result guarantees that one can avoi...

  10. Optical observations of the nearby galaxy IC342 with narrow band [SII] and H$\\alpha$ filters. II - Detection of 16 Optically-Identified Supernova Remnant Candidates

    Vucetic, M M; Pavlovic, M Z; Pannuti, T G; Petrov, N; Goker, U D; Ercan, E N

    2015-01-01

    We present the detection of 16 optical supernova remnant (SNR) candidates in the nearby spiral galaxy IC342. The candidates were detected by applying [SII]/H$\\alpha$ ratio criterion on observations made with the 2 m RCC telescope at Rozhen National Astronomical Observatory in Bulgaria. In this paper, we report the coordinates, diameters, H$\\alpha$ and [SII] fluxes for 16 SNRs detected in two fields of view in the IC342 galaxy. Also, we estimate that the contamination of total H$\\alpha$ flux from SNRs in the observed portion of IC342 is 1.4%. This would represent the fractional error when the star formation rate (SFR) for this galaxy is derived from the total galaxy's H$\\alpha$ emission.

  11. Detailed comparison of downflows seen both in EIT 30.4 nm and Big Bear H alpha movies

    De Groof, Anik; Bastiaensen, Cindy; Muller, DAN; Berghmans, D.; Poedts, Stefaan

    2005-01-01

    An EIT shutterless campaign was conducted on 11 July 2001 and provided 120 high-cadence (68 s) 30.4 nm images of the north-eastern quarter of the Sun. Systematic intensity variations are seen which appear to propagate along an off-disk loop-like structure. In this paper we study the nature of these intensity variations by confronting the EIT observations studied in De Groof et al. (2004, A&A, 415, 1141) with simultaneous H alpha images from Big Bear Solar Observatory.

  12. Comparison of the H-alpha circumstellar disks in Be/X-ray binaries and Be stars

    Zamanov, R. K.; Reig, P.; Marti, J.; Coe, M. J.; Fabregat, J.; Tomov, N.A.; Valchev, T.

    2000-01-01

    We present a comparative study of the circumstellar disks in Be/X-ray binaries and isolated Be stars based upon the H-alpha emission line. From this comparison it follows that the overall structure of the disks in the Be/X-ray binaries is similar to the disks of other Be stars, i.e. they are axisymmetric and rotationally supported. The factors for the line broadening (rotation and temperature) in the disks of the Be stars and the Be/X-ray binaries seem to be identical. However, we do detect s...

  13. Initial Data Release from the INT Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS)

    González-Solares, E A; Greimel, R; Drew, J E; Irwin, M J; Sale, S E; Andrews, K; Aungwerojwit, A; Barlow, M J; Besselaar, E van den; Corradi, R L M; Gänsicke, B T; Groot, P J; Hales, A S; Hopewell, E C; Hu, H; Irwin, J; Knigge, C; Lagadec, E; Leisy, P; Lewis, J R; Mampaso, A; Matsuura, M; Moont, B; Morales-Rueda, L; Morris, R A H; Naylor, T; Parker, Q A; Prema, P; Pyrzas, S; Rixon, G T; Rodríguez-Gil, P; Roelofs, G; Sabin, L; Skillen, I; Suso, J; Tata, R; Viironen, K; Vink, J S; Witham, A; Wright, N J; Zijlstra, A A; Zurita, A; Drake, J; Fabregat, J; Lennon, D J; Lucas, P W; Martín, E L; Steeghs, D; Unruh, Y C

    2007-01-01

    The INT/WFC Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS) is an imaging survey being carried out in H-alpha, r' and i' filters, with the Wide Field Camera (WFC) on the 2.5-metre Isaac Newton Telescope (INT) to a depth of r'=20 (10 sigma). The survey is aimed at revealing large scale structure in our local galaxy, and also the properties of key early and late populations making up the Milky Way. Mapping emission line objects enables a particular focus on objects in the young and old stages of stellar evolution ranging from early T-Tauri stars to late planetary nebulae. In this paper we present the IPHAS Initial Data Release, primarily a photometric catalogue of about 200 million unique objects, coupled with associated image data covering about 1600 square degrees in three passbands. We note how access to the primary data products has been implemented through use of standard virtual observatory publishing interfaces. Simple traditional web access is provided to the main IPHAS photometric cat...

  14. Fluxes in H\\alpha and Ca II H and K for a sample of Southern stars

    Cincunegui, C; Mauas, P J D; Cincunegui, Carolina; D\\'iaz, Rodrigo F.; Mauas, Pablo J. D.

    2007-01-01

    The main chromospheric activity indicator is the S index, which is esentially the ratio of the flux in the core of the Ca II H and K lines to the continuum nearby, and is well studied basically for stars from F to K. Another usual chromospheric proxy is the H\\alpha line, which is beleived to be tightly correlated with the Ca II index. In this work we characterize both chromospheric activity indicators, one associated with the H and K Ca II lines and the other with H\\alpha, for the whole range of late type stars, from F to M. We present periodical medium-resolution echelle observations covering the complete visual range, which were taken at the CASLEO Argentinean Observatory. These observations are distributed along 7 years. We use a total of 917 flux-calibrated spectra for 109 stars which range from F6 to M5. We statistically study these two indicators for stars of different activity levels and spectral types. We directly derive the conversion factor which translate the known S index to flux in the Ca II core...

  15. GHASP : an H alpha kinematic survey of spiral and irregular galaxies. V. Dark matter distribution in 36 nearby spiral galaxies

    Spano, M; Amram, P; Carignan, C; Epinat, B; Hernndez, O

    2007-01-01

    The results obtained from a study of the mass distribution of 36 spiral galaxies are presented. The galaxies were observed using Fabry-Perot interferometry as part of the GHASP survey. The main aim of obtaining high resolution H alpha 2D velocity fields is to define more accurately the rising part of the rotation curves which should allow to better constrain the parameters of the mass distribution. The H alpha velocities were combined with low resolution HI data from the literature, when available. Combining the kinematical data with photometric data, mass models were derived from these rotation curves using two different functional forms for the halo: an isothermal sphere and an NFW profile. For the galaxies already modeled by other authors, the results tend to agree. Our results point at the existence of a constant density core in the center of the dark matter halos rather than a cuspy core, whatever the type of the galaxy from Sab to Im. This extends to all types the result already obtained by other author...

  16. Heavily Reddened z~2 Type 1 Quasars II: H-alpha Star Formation Constraints from SINFONI IFU Observations

    Alaghband-Zadeh, Susannah; Hewett, Paul C; McMahon, Richard G

    2016-01-01

    We use near infrared integral field unit (IFU) spectroscopy to search for H$\\alpha$ emission associated with star formation in a sample of 28 heavily reddened ($E(B-V)\\simeq$0.5-1.9), hyperluminous ($log(L_{bol}/ergs^{-1})\\simeq$47-48) broad-line quasars at $z\\simeq$1.4-2.7. Sixteen of the 28 quasars show evidence for star formation with an average extinction-corrected star formation rate (SFR) of 320$\\pm$70M$_\\odot$yr$^{-1}$. A stacked spectrum of the detections shows weak [NII], consistent with star formation as the origin of the narrow H$\\alpha$ emission. The star-forming regions are spatially unresolved in 11 of the 16 detections and constrained to lie within $\\sim$6kpc of the quasar emission. In the five resolved detections we find the star-forming regions are extended on scales of $\\sim$8kpc around the quasar emission. The prevalence of high SFRs is consistent with the identification of the heavily reddened quasar population as representing a transitional phase from apparent `starburst galaxies' to opti...

  17. On the relationship between soft X-rays and H-alpha-emitting structures during a solar flare

    Zirin, H.; Feldman, U.; Doschek, G. A.; Kane, S.

    1981-01-01

    Based on data obtained during a solar flare on March 31, 1979, soft X-ray (SXR) and hard X-ray (HXR) bursts are analyzed and compared with other available data in order to identify structures in H-alpha that may correspond to the SXR-emitting site. Measurements taken with the X-ray telescope and the XUV spectroheliograph flown on Skylab, have shown that the SXR emission from many flares comes from rather small structures of about 10-20 arcsec across. These structures appear to be loops that cross the magnetic neutral line. Understanding of the morphology of SXR was based on data of the solar flare of June 15, 1973, observed from Skylab, and the work of Moore et al., (1980). Dense, highly emissive coronal structures, not suggested to be the X-ray source, were forming, lost energy rapidly by emission and conduction, and finally formed the loops. It is concluded that bright H-alpha loops form rapidly as the SXR emission rises, and the overall decay (cooling rate) of SXR emission is much slower than the formation time of individual loops.

  18. A search for Ejecta Nebulae around Wolf-Rayet Stars using the SHS H$\\alpha$ survey

    Stock, D J

    2010-01-01

    Recent large scale Galactic Plane H$\\alpha$ surveys allow a re-examination of the environs of Wolf-Rayet (WR) stars for the presence of a circumstellar nebula. Using the morphologies of WR nebulae known to be composed of stellar ejecta as a guide, we constructed ejecta nebula criteria similar to those of Chu (1991) and searched for likely WR ejecta nebula in the SHS H$\\alpha$ survey. A new Wolf-Rayet ejecta nebula around WR 8 is found and its morphology discussed. The fraction of WR stars with ejecta type nebulae is roughly consistent between the MilkyWay (MW) and LMC at around 5-6%, with the MW sample dominated by nitrogen rich WR central stars (WN type) and the LMC stars having a higher proportion of carbon rich WR central stars (WC type). We compare our results with those of previous surveys, including those of Marston (1997) and Miller & Chu (1993), and find broad consistency. We investigate several trends in the sample: most of the clear examples of ejecta nebulae have WNh central stars; and very few...

  19. H{\\alpha} and UV luminosities and star formation rates in a large sample of luminous compact galaxies

    Parnovsky, S L; Izotov, Y I

    2012-01-01

    We present the results of a statistical study of the star formation rates (SFR) derived from the Galaxy Evolution Explorer (GALEX) observations in the ultraviolet continuum and in the H\\alpha emission line for a sample of about 800 luminous compact galaxies (LCGs). Galaxies in this sample have a compact structure and include one or several regions of active star formation. Global galaxy characteristics (metallicity, luminosity, stellar mass) are intermediate between ones of the nearby blue compact dwarf (BCD) galaxies and Lyman-break galaxies (LBGs) at high redshifts z > 2 - 3. SFRs were corrected for interstellar extinction which was derived from the optical Sloan Digital Sky Survey (SDSS) spectra. We find that SFRs derived from the galaxy luminosities in the far ultraviolet (FUV) and near ultraviolet (NUV) ranges vary in a wide range from 0.18 M_Sun/yr to 113 M_Sun/yr with median values of 3.8 M_Sun/yr and 5.2 M_Sun/yr, respectively. Simple regression relations are found for luminosities L(H\\alpha) and L(UV...

  20. Multi-epoch Spectroscopy of Dwarf Galaxies with AGN Signatures: Identifying Sources with Persistent Broad H-alpha Emission

    Baldassare, Vivienne F; Gallo, Elena; Greene, Jenny E; Graur, Or; Geha, Marla; Hainline, Kevin; Carroll, Christopher M; Hickox, Ryan C

    2016-01-01

    We use time-domain optical spectroscopy to distinguish between broad emission lines powered by accreting black holes (BHs) or stellar processes (i.e., supernovae) for 16 galaxies identified as AGN candidates by Reines et al. (2013). 14 of these have star-formation--dominated narrow-line emission ratios, one is a narrow-line AGN, and the last is a star-forming--AGN composite. We find that broad H$\\alpha$ emission has faded for 11/16 targets, based on spectra taken with the Magellan Echellette Spectrograph (MagE), the Dual Imaging Spectrograph, and the Ohio State Multi-Object Spectrograph with baselines ranging from 5 to 14 years. The 11 faded systems all have narrow-line ratios consistent with recent star formation, suggesting the broad emission for those targets was produced by a transient stellar process. The two objects with narrow-line AGN signatures (RGG 9 and RGG 119) have persistent broad H$\\alpha$ emission consistent with previous SDSS observations. The final three star-forming objects are classified a...

  1. Using MHD simulations to model H-alpha and UV spectral lines for interpretation of IRIS and NST data

    Sadykov, Viacheslav M

    2014-01-01

    We present results of non-LTE modeling of H-alpha 6563 A and Mg II k&h 2796 A and 2803 A lines. This modeling is important for interpretation of coordinated observations from the recently launched NASA's IRIS mission and from the New Solar Telescope at Big Bear Solar Observatory. Among available codes for the non-LTE modeling, the RH code is chosen as the most appropriate for modeling of the line profiles. The most suitable Hydrogen and Magnesium atomic models are selected by performing several tests of the code. The influence of the ionization degree on the line profiles is also studied. Radiative-MHD simulations of the solar atmosphere, obtained with the Bifrost code, are used as input data for calculation of synthetic spectra of the H-alpha and Mg II h&k lines for particular locations evolving with time. The spectral line variations reveal the presence of MHD waves in the simulation results. We construct oscillation power spectra of the line intensity for different wavelength, and compare these wit...

  2. Alpha widths from nuclear models

    Methods to calculate alpha widths from nuclear model wavefunctions are reviewed and the underlying assumptions discussed. Comparison of experimental and calculated reduced widths is made. Some new results on absolute values of alpha transition rates are reported

  3. COMPARING H{alpha} AND H I SURVEYS AS MEANS TO A COMPLETE LOCAL GALAXY CATALOG IN THE ADVANCED LIGO/VIRGO ERA

    Metzger, Brian D. [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08542 (United States); Kaplan, David L. [Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI 53211 (United States); Berger, Edo, E-mail: bmetzger@astro.princeton.edu, E-mail: kaplan@uwm.edu, E-mail: eberger@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2013-02-20

    Identifying the electromagnetic counterparts of gravitational wave (GW) sources detected by upcoming networks of advanced ground-based interferometers will be challenging, due in part to the large number of unrelated astrophysical transients within the {approx}10-100 deg{sup 2} sky localizations. A potential way to greatly reduce the number of such false positives is to limit detailed follow-up to only those candidates near galaxies within the GW sensitivity range of {approx}200 Mpc for binary neutron star mergers. Such a strategy is currently hindered by the fact that galaxy catalogs are grossly incomplete within this volume. Here, we compare two methods for completing the local galaxy catalog: (1) a narrowband H{alpha} imaging survey and (2) an H I emission line radio survey. Using H{alpha} fluxes, stellar masses (M {sub *}), and star formation rates (SFRs) from galaxies in the Sloan Digital Sky Survey (SDSS), combined with H I data from the GALEX Arecibo SDSS Survey and the Herschel Reference Survey, we estimate that an H{alpha} survey with a luminosity sensitivity of L {sub H{alpha}} = 10{sup 40} erg s{sup -1} at 200 Mpc could achieve a completeness of f {sup H{alpha}} {sub SFR} Almost-Equal-To 75% with respect to total SFR, but only f{sub M* Star-Operator }{sup H{alpha}} approx. 33% with respect to M {sub *} (due to lack of sensitivity to early-type galaxies). These numbers are significantly lower than those achieved by an idealized spectroscopic survey due to the loss of H{alpha} flux resulting from resolving out nearby galaxies and the inability to correct for the underlying stellar continuum. An H I survey with sensitivity similar to the proposed WALLABY survey on ASKAP could achieve f{sub SFR}{sup H{sub I}} Almost-Equal-To 80% and f{sub M Star-Operator }{sup H{sub I}} Almost-Equal-To 50%, somewhat higher than that of the H{alpha} survey. Finally, both H{alpha} and H I surveys should achieve {approx}> 50% completeness with respect to the host galaxies of short-duration gamma-ray bursts, which may trace the population of binary neutron star mergers.

  4. Comparison of 30 THz impulsive burst time development to microwaves, H-alpha, EUV, and GOES soft X-rays

    Miteva, R; Cabezas, D P; Cassiano, M M; Fernandes, L O T; Freeland, S L; Karlicky, M; Kerdraon, A; Kudaka, A S; Luoni, M L; Marcon, R; Raulin, J -P; Trottet, G; White, S M

    2015-01-01

    The recent discovery of impulsive solar burst emission in the 30 THz band is raising new interpretation challenges. One event associated with a GOES M2 class flare has been observed simultaneously in microwaves, H-alpha, EUV, and soft X-ray bands. Although these new observations confirm some features found in the two prior known events, they exhibit time profile structure discrepancies between 30 THz, microwaves, and hard X-rays (as inferred from the Neupert effect). These results suggest a more complex relationship between 30 THz emission and radiation produced at other wavelength ranges. The multiple frequency emissions in the impulsive phase are likely to be produced at a common flaring site lower in the chromosphere. The 30 THz burst emission may be either part of a nonthermal radiation mechanism or due to the rapid thermal response to a beam of high-energy particles bombarding the dense solar atmosphere.

  5. Digital Pulse-Width-Modulation Circuit

    Wenzler, Carl J.; Eichenberg, Dennis J.

    1995-01-01

    Digital pulse-width-modulation circuit provides programmable duration from 1 microsecond to full on, at repetition rate of 1 kHz. Designed for use in controlling CO2 laser, also used in applications in which precision and flexibility of digital control of pulse durations needed. Circuit incorporates low-power Schottky transistor/transistor-logic (TTL) devices in critical high-speed parts. Designed in TTL to make it compatible with Pro-Log 7914 (or equivalent) decoder input/output (I/O) utility printed-circuit card.

  6. Classical T Tauri stars with VPHAS$+$: I: H$\\alpha$ and $u$-band accretion rates in the Lagoon Nebula M8

    Kalari, V M; Drew, J E; Barentsen, G; Drake, J J; Eislffel, J; Martn, E L; Parker, Q A; Unruh, Y C; Walton, N A; Wright, N J

    2015-01-01

    We estimate the accretion rates of 235 Classical T Tauri star (CTTS) candidates in the Lagoon Nebula using $ugri$H$\\alpha$ photometry from the VPHAS+ survey. Our sample consists of stars displaying H$\\alpha$-excess, the intensity of which is used to derive accretion rates. For a subset of 87 stars, the intensity of the $u$-band excess is also used to estimate accretion rates. We find the mean variation in accretion rates measured using H$\\alpha$ and $u$-band intensities to be $\\sim$ 0.17 dex, agreeing with previous estimates (0.04-0.4 dex) but for a much larger sample. The spatial distribution of CTTS align with the location of protostars and molecular gas suggesting that they retain an imprint of the natal gas fragmentation process. Strong accretors are concentrated spatially, while weak accretors are more distributed. Our results do not support the sequential star forming processes suggested in the literature.

  7. Detection of an H-alpha Emission Line on a Quasar, RX J1759.4+6638, at z=4.3 with AKARI

    Oyabu, Shinki; Ohyama, Youichi; Matsuhara, Hideo; Takagi, Toshinobu; Nakagawa, Takao; Onaka, Takashi; Fujishiro, Naofumi; Ishihara, Daisuke; Ita, Yoshifusa; Kataza, Hirokazu; Kim, Woojung; Matsumoto, Toshio; Murakami, Hiroshi; Sakon, Itsuki; Tanabe, Toshihiko; Uemizu, Kazunori; Ueno, Munetaka; Usui, Fumihiko; Watarai, Hidenori; Haze, Kanae

    2007-01-01

    We report the detection of an H-alpha emission line in the low resolution spectrum of a quasar, RX J1759.4+6638, at a redshift of 4.3 with the InfraRed Camera (IRC) onboard the AKARI. This is the first spectroscopic detection of an H-alpha emission line in a quasar beyond z=4. The overall spectral energy distribution (SED) of RX J1759.4+6638 in the near- and mid-infrared wavelengths agrees with a median SED of the nearby quasars and the flux ratio of F(Ly-alpha)/F(H-alpha) is consistent with those of previous reports for lower-redshift quasars.

  8. Phase width reduction project summary

    The purpose of the phase width reduction project, 1993--96, was to reduce the phase width of the 88-Inch Cyclotron beam on target from 5--10 ns to 1--2 ns for certain experiments, such as Gammasphere, which use time-of-flight identification. Since reducing the phase width also reduces beam intensity, tuning should be done to also optimize the transmission. The Multi-turn Collimator slits in the cyclotron center region were used to collimate the early turns radially, thus reducing the phase width from about 5 ns to 1--2 ns FWHM for a Gammasphere beam. The effect of the slits on phase width was verified with a Fast Faraday Cup and with particle and gamma-ray detectors in the external beamline

  9. ZFIRE: Galaxy Cluster Kinematics, H$\\alpha$ Star Formation Rates, and Gas-Phase Metallicities of XMM-LSS J02182-05102 at z=1.6233

    Tran, Kim-Vy H; Yuan, Tiantian; Kacprzak, Glenn G; Glazebrook, Karl; Kewley, Lisa J; Momcheva, Ivelina; Papovich, Casey J; Quadri, Ryan; Rudnick, Greg; Saintonge, Amélie; Spitler, Lee R; Straatman, Caroline; Tomczak, Adam

    2015-01-01

    We spectroscopically survey the galaxy cluster XMM-LSS J02182-05102 (hereafter IRC 0218) using LRIS (optical) and MOSFIRE (near-infrared) on Keck I as part of the ZFIRE survey. IRC 0218 has a narrow redshift range of $1.612H$\\alpha$ star formation rates (SFR), gas phase metallicities from [NII]/H$\\alpha$, and stellar masses. We measure an integrated H$\\alpha$ SFR of $\\sim325{\\rm M}_{\\odot}$ yr$^{-1}$ (26 members; R$_{\\rm proj}<2$ Mpc) and show that the elevated star formation in the cluster core (R$_{\\rm proj}<0.25$ Mpc) is driven by the concentration of star-forming members, but the average SFR per H$\\alpha$-detected galaxy is half th...

  10. Discovery of an Apparent Nova in M81 and an Increase of H-alpha Emission from PNV J09553488+6910194

    Hornoch, K.; Vaduvescu, O.; Stoev, H.

    2014-03-01

    We report the discovery of an apparent nova in M81 on a co-added 2000-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma under ~1.5" seeing on 2014 Mar. ...

  11. Discovery of an Apparent Nova in M81 and H-alpha Confirmation of PNV J09560160+6903126 and PNV J09553945+6905557

    Hornoch, K.; Stoev, H.; Tudor, V.; Vaduvescu, O.; Frigo, M.

    2014-05-01

    We report the discovery of an apparent nova in M81 galaxy on a co-added 2000-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma under ~1.2" seeing on 2014 May 26.923 UT. ...

  12. HiZELS: a high redshift survey of H-alpha emitters. II: the nature of star-forming galaxies at z=0.84

    Sobral, D; Geach, J E; Smail, Ian; Kurk, J; Cirasuolo, M; Casali, M; Ivison, R J; Coppin, K; Dalton, G B

    2009-01-01

    New results from a large survey of H-alpha emission-line galaxies at z=0.84 using WFCAM/UKIRT and a custom narrow-band filter in the J band are presented as part of the HiZELS survey. Reaching an effective flux limit of 1e-16 erg/s/cm^2 in a comoving volume of 1.8e5 Mpc^3, this represents the largest and deepest survey of its kind ever done at z~1. There are 1517 potential line emitters detected across 1.4 sq.deg of the COSMOS and UKIDSS UDS fields, of which 743 are selected as H-alpha emitters. These are used to calculate the H-alpha luminosity function, which is well-fitted by a Schechter function with phi*=10^(-1.92+-0.10) Mpc^-3, L*=10^(42.26+-0.05)erg/s, and alpha=-1.65+-0.15. The integrated star formation rate density (SFRD) at z=0.845 is 0.15+-0.01 M_sun/yr/Mpc^3. The results robustly confirm a strong evolution of SFRD from the present day out to z~1 and then flattening to z~2, using a single star-formation indicator. Out to z~1, both the characteristic luminosity and space density of the H-alpha emitt...

  13. The MOSDEF Survey: Dissecting the star-formation rate vs. stellar mass relation using H$\\alpha$ and H$\\beta$ emission lines at z ~ 2

    Shivaei, Irene; Shapley, Alice E; Kriek, Mariska; Siana, Brian; Mobasher, Bahram; Coil, Alison L; Freeman, William R; Sanders, Ryan; Price, Sedona H; de Groot, Laura; Azadi, Mojegan

    2015-01-01

    We present results on the SFR-$M_*$ relation (i.e., the "main sequence") among star-forming galaxies at $1.37\\leq z \\leq2.61$ using the MOSFIRE Deep Evolution Field (MOSDEF) survey. Based on a sample of 261 star-forming galaxies with observations of H$\\alpha$ and H$\\beta$ emission lines, we have estimated robust dust-corrected instantaneous star-formation rates (SFRs) over a large dynamic range in stellar mass ($\\sim 10^{9.0}-10^{11.5}M_\\odot$). We find a tight correlation between SFR(H$\\alpha$) and $M_*$ with an intrinsic scatter of 0.36 dex, 0.05 dex larger than that of UV-based SFRs. This increased scatter is consistent with predictions from numerical simulations of 0.03 - 0.1 dex, and is attributed to H$\\alpha$ more accurately tracing SFR variations. The slope of the $\\log(\\text{SFR})-\\log(M_*)$ relation, using SFR(H$\\alpha$), at $1.4< z<2.6$ and over the stellar mass range of $10^{9.5}$ to $10^{11.5}M_\\odot$ is $0.65\\pm 0.09$. We find that different assumptions for the dust correction, such as usin...

  14. The Wyoming Survey for H-alpha. III. A Multi-wavelength Look at Attenuation by Dust in Galaxies out to z~0.4

    Moore, Carolynn A; Barlow, Rebecca J; Cohen, Seth A; Cook, David O; Johnson, L C; Kattner, ShiAnne M; Lee, Janice C; Staudaher, Shawn M

    2010-01-01

    We report results from the Wyoming Survey for H-alpha (WySH), a comprehensive four-square degree survey to probe the evolution of star-forming galaxies over the latter half of the age of the Universe. We have supplemented the H-alpha data from WySH with infrared data from the Spitzer Wide-area Infrared Extragalactic (SWIRE) Survey and ultraviolet data from the Galaxy Evolution Explorer (GALEX) Deep Imaging Survey. This dataset provides a multi-wavelength look at the evolution of the attenuation by dust, and here we compare a traditional measure of dust attenuation (L(TIR)/L(FUV)) to a diagnostic based on a recently-developed robust star formation rate (SFR) indicator, [H-alpha_obs+24-micron]/H-alpha_obs. With such data over multiple epochs, the evolution in the attenuation by dust with redshift can be assessed. We present results from the ELAIS-N1 and Lockman Hole regions at z~0.16, 0.24, 0.32 and 0.40. While the ensemble averages of both diagnostics are relatively constant from epoch to epoch, each epoch ind...

  15. A deterministic width function model

    C. E. Puente

    2003-01-01

    Full Text Available Use of a deterministic fractal-multifractal (FM geometric method to model width functions of natural river networks, as derived distributions of simple multifractal measures via fractal interpolating functions, is reported. It is first demonstrated that the FM procedure may be used to simulate natural width functions, preserving their most relevant features like their overall shape and texture and their observed power-law scaling on their power spectra. It is then shown, via two natural river networks (Racoon and Brushy creeks in the United States, that the FM approach may also be used to closely approximate existing width functions.

  16. Probabilistic Analysis of Crack Width

    J. Marková

    2000-01-01

    Full Text Available Probabilistic analysis of crack width of a reinforced concrete element is based on the formulas accepted in Eurocode 2 and European Model Code 90. Obtained values of reliability index b seem to be satisfactory for the reinforced concrete slab that fulfils requirements for the crack width specified in Eurocode 2. However, the reliability of the slab seems to be insufficient when the European Model Code 90 is considered; reliability index is less than recommended value 1.5 for serviceability limit states indicated in Eurocode 1. Analysis of sensitivity factors of basic variables enables to find out variables significantly affecting the total crack width.

  17. H$\\alpha$ Velocity Fields and Galaxy Interaction in the Quartet of Galaxies NGC 7769, 7770, 7771 and 7771A

    A. A. Yeghiazaryan; T. A. Nazaryan; A. A. Hakobyan

    2016-03-01

    The quartet of galaxies NGC 7769, 7770, 7771 and 7771A is a system of interacting galaxies. Close interaction between galaxies caused characteristic morphological features: tidal arms and bars, as well as an induced star formation. In this study, we performed the Fabry–Perot scanning interferometry of the system in H\\alpha line and studied the velocity fields of the galaxies. We found that the rotation curve of NGC 7769 is weakly distorted. The rotation curve of NGC 7771 is strongly distorted with the tidal arms caused by direct flyby of NGC 7769 and flyby of a smaller neighbor NGC 7770. The rotation curve of NGC 7770 is significantly skewed because of the interaction with the much massive NGC 7771. The rotation curves and morphological disturbances suggest that the NGC 7769 and NGC 7771 have passed the first pericenter stage, however, probably the second encounter has not happened yet. Profiles of surface brightness of NGC 7769 have a characteristic break, and profiles of color indices have a minimum at a radius of intensive star formation induced by the interaction with NGC 7771.

  18. ESO-H$\\alpha$~574 and Par-Lup3-4 Jets: Exploring the spectral, kinematical and physical properties

    Whelan, E T; Antoniucci, S; Alcal, J M; Giannini, T; Nisini, B; Bacciotti, F; Podio, L; Stelzer, B; Comern, F

    2014-01-01

    In this paper a comprehensive analysis of VLT / X-Shooter observations of two jet systems, namely ESO-H$\\alpha$ 574 a K8 classical T Tauri star and Par-Lup 3-4 a very low mass (0.13~\\Msun) M5 star, is presented. Both stars are known to have near-edge on accretion disks. A summary of these first X-shooter observations of jets was given in a 2011 letter. The new results outlined here include flux tables of identified emission lines, information on the morphology, kinematics and physical conditions of both jets and, updated estimates of $\\dot{M}_{out}$ / $\\dot{M}_{acc}$. Asymmetries in the \\eso flow are investigated while the \\para jet is much more symmetric. The density, temperature, and therefore origin of the gas traced by the Balmer lines are investigated from the Balmer decrements and results suggest an origin in a jet for \\eso while for \\para the temperature and density are consistent with an accretion flow. $\\dot{M}_{acc}$ is estimated from the luminosity of various accretion tracers. For both targets, ne...

  19. HST/ACS H-alpha Imaging of the Carina Nebula: Outflow Activity Traced by Irradiated Herbig-Haro Jets

    Smith, Nathan; Walborn, Nolan R

    2010-01-01

    We report the discovery of new Herbig-Haro (HH) jets in the Carina Nebula, and we discuss the protostellar outflow activity of a young OB association. These are the first results of an HST/ACS H-alpha imaging survey of Carina. Adding to the one previously known example (HH666), we detect 21 new HH jets, plus 17 new candidate jets, ranging in length from 0.005 to 3 pc. We derive jet mass-loss rates ranging from 8e-9 to 1e-6 Msun/yr, but a comparison to the distribution of jet mass-loss rates in Orion suggests that we may be missing a large fraction of the jets below 1e-8 Msun/yr. A key qualitative result is that even some of the smallest dark globules with sizes of 0.01pc are active sites of ongoing star formation because we see HH jets emerging from them, and that these offer potential analogs to the cradle of our Solar System because of their proximity to dozens of imminent supernovae that will enrich them with radioactive nuclides like 60Fe. HST images reveal proplyd structures in the core of the Tr14 clust...

  20. Star formation at z=1.47 from HiZELS: An H{\\alpha}+[OII] double-blind study

    Sobral, David; Matsuda, Yuichi; Smail, Ian; Geach, James; Cirasuolo, Michele

    2011-01-01

    This paper presents the results from the first wide and deep dual narrow-band survey to select H-alpha (Ha) and [OII] line emitters at z=1.47\\pm0.02 (using matched narrow-band filters in the H and z' bands), exploiting synergies between the UKIRT and Subaru telescopes. The Ha survey at z=1.47 reaches a flux limit of ~7x10^-17 erg/s/cm^2 and detects ~200 Ha emitters over 0.7deg^2, while the much deeper [OII] survey reaches an effective flux of ~7x10^-18 erg/s/cm^2, detecting ~1400 z=1.47 [OII] emitters in a matched co-moving volume of ~2.5x10^5 Mpc^3. The combined survey results in the identification of 190 simultaneous Ha and [OII] emitters at z=1.47. Ha and [OII] luminosity functions are derived and both are shown to evolve significantly from z~0 in a consistent way. The star formation rate density of the Universe at z=1.47 is evaluated, with the Ha analysis yielding 0.16\\pm0.05 M_sun/yr/Mpc^3 and the [OII] analysis 0.17\\pm0.04 M_sun/yr/Mpc^3. The measurements are combined with other studies, providing a sel...

  1. STAR FORMATION PROPERTIES IN THE LOCAL VOLUME GALAXIES VIA H{alpha} AND FAR-ULTRAVIOLET FLUXES

    Karachentsev, Igor D.; Kaisina, Elena I., E-mail: ikar@sao.ru, E-mail: kei@sao.ru [Special Astrophysical Observatory, Russian Academy of Sciences, Nizhnij Arkhyz, Karachai-Cherkessian Republic 369167 (Russian Federation)

    2013-09-15

    A distance-limited sample of 869 objects from the Updated Nearby Galaxy Catalog is used to characterize the star formation status of the Local Volume population. We present a compiled list of 1217 star formation rate (SFR) estimates for 802 galaxies within 11 Mpc, derived from the H{alpha} imaging surveys and the GALEX far-ultraviolet survey. We briefly discuss some basic scaling relations between SFR and luminosity, morphology, H I mass, surface brightness, and the environment of the galaxies. About 3/4 of our sample consist of dwarf galaxies, for which we offer a more refined classification. We note that the specific SFR of nearly all luminous and dwarf galaxies does not exceed the maximum value: log (SFR/L{sub K} ) = -9.4 [yr{sup -1}]. Most spiral and blue dwarf galaxies have enough time to generate their stellar mass during the cosmological time, T{sub 0}, with the observed SFRs. They dispose of a sufficient amount of gas to support their present SFRs over the next T{sub 0} term. We note that only a small fraction of BCD, Im, and Ir galaxies (about 1/20) proceed in a mode of vigorous starburst activity. In general, the star formation history of spiral and blue dwarf galaxies is mainly driven by their internal processes. The present SFRs of E, S0, and dSph galaxies typically have 1/30-1/300 of their former activity.

  2. Short timescale variations of the H{\\alpha} double-peaked profile of the nucleus of NGC 1097

    Schimoia, Jaderson S; Nemmen, Rodrigo S; Winge, Cludia; Eracleous, Michael; 10.1088/0004-637X/748/2/145

    2012-01-01

    The broad (FWHM ~ 10,000 km/s) double-peaked H{\\alpha} profile from the LINER/Seyfert 1 nucleus of NGC 1097 was discovered in 1991, and monitored for the following 11 years. The profile showed variations attributed to the rotation of gas in a non-axisymmetric Keplerian accretion disk, ionized by a varying radiatively inefficient accretion flow (RIAF) located in the inner parts of the disk. We present and model 11 new spectroscopic observations of the double-peaked profile taken between 2010 March and 2011 March. This series of observations was motivated by the finding that in 2010 March the flux in the double-peaked line was again strong, becoming, in 2010 December, even stronger than in the observations of a decade ago. We also discovered shorter timescale variations than in the previous observations: (1) the first, of ~7 days, is interpreted as due to "reverberation" of the variation of the ionizing source luminosity, and the timescale of 7 days as the light crossing time between the source and the accretio...

  3. Width difference of ? vector mesons

    We compute the difference in decay widths between charged and neutral ?(770) vector mesons. The isospin breaking arising from mass differences of neutral and charged ? and ? mesons, radiative corrections to ????, and the ????? decays are taken into account. It is found that the width difference ??? is very sensitive to the isospin breaking in the ? meson mass, ?m?. This result can be useful to test the correlations observed between the values of these parameters extracted from experimental data

  4. Characterizing the width of entanglement

    Wölk, Sabine; Gühne, Otfried

    2015-01-01

    We introduce the concept of entanglement width as measure of the spatial distribution of entanglement in multiparticle systems. We develop criteria to detect the width of entanglement using global observables such as energy and magnetic susceptibility. Therefore, the introduced entanglement criteria can be applied to systems where addressing of single particles is not possible. We apply the criteria to different examples such as the J1-J2- Heisenberg model and point out the difference between...

  5. Biological width: No violation zone

    Ashu Sharma

    2012-01-01

    Full Text Available Maintenance of gingival health is one of the keys for the longevity of teeth, as well as for the longevity of restorations. The concept of Biologic width has been widely described by periodontists and restorative dentists. An adequate understanding of relationship between periodontal tissues and restorative dentistry is paramount to ensure adequate form, function and esthetics, and comfort of the dentition. While most clinicians are aware of this important relationship, uncertainty remains regarding specific concepts such as biologic width and indications and applications of surgical crown lengthening. These violations lead to complications like gingival inflammation, alveolar bone loss and improper fit of the restorative component. This review gives the wide aspect of the complex question of biologic width and represents an attempt to answer some of the demands in relation to it. The article also discusses the possible methods to assess biologic width, problems that occur after improper margin placement in the periodontium and the alternative procedures for prevention of biological width violation.

  6. The RINGS Survey: High-Resolution H-alpha Velocity Fields of Nearby Spiral Galaxies with the SALT Fabry-Perot

    Mitchell, Carl J; Williams, T B; Spekkens, Kristine; Lee-Waddell, K; de Naray, Rachel Kuzio

    2015-01-01

    We have obtained high-spatial-resolution spectrophotometric data on several nearby spiral galaxies with the Southern African Large Telescope (SALT) Fabry-P\\'erot interferometer on the Robert Stobie Spectrograph (RSS) as a part of the RSS Imaging spectroscopy Nearby Galaxy Survey (RINGS). We have successfully reduced two tracks of Fabry-P\\'erot data for the galaxy NGC 2280 to produce a velocity field of the H-alpha line of excited hydrogen. We have modeled these data with the DiskFit modeling software and found these models to be in excellent agreement both with previous measurements in the literature and with our lower-resolution HI velocity field of the same galaxy. Despite this good agreement, small regions exist where the difference between the H-alpha and HI velocities is larger than would be expected from typical dispersions. We investigate these regions of high velocity difference and offer possible explanations for their existence.

  7. Chromospheric Ca II H and K and H-alpha emission in single and binary stars of spectral types F6-M2

    Strassmeier, Klaus G.; Fekel, Francis C.; Bopp, Bernard W.; Dempsey, Robert C.; Henry, Gregory W.

    1990-01-01

    New observations of the Ca II H and K and H-epsilon region and/or the Balmer H-alpha line are presented for 100 mostly very active stars but also for weak or inactive stars with suspected activity. Correlations between chromospheric activity at Ca II H and K and H-alpha and effective surface temperature and rotation are identified, and several new stars with chromospheric Ca II H and K emission are discovered. No single activity-rotation relation can be derived for all luminosity classes, and there is clear evidence that evolved stars are generally more active than main-sequence stars of the same rotation period. Binary within the evolved stars appears to play no role, while main-sequence binary stars show generally higher levels of activity than their single counterparts. Chromospheric emission in the Ca II H and K lines depends on surface temperature in that flux declines with cooler temperature.

  8. Width of radiative decay ?(1520)???

    The radiative decay ?(1520)??? was measured in the study of exclusive reaction p+N??(1520)K++N with the SPHINX spectrometer. The values of branching ratio and partial width of this decay were determined: BR[?(1520)???]=(1.020.21)x10-2 and ?[?(1520)???]=15935 keV (statistical uncertainty; systematic uncertainty is below 15 %)

  9. The Subaru FMOS Galaxy Redshift Survey (FastSound). I. Overview of the Survey Targeting on H$\\alpha$ Emitters at $z \\sim 1.4$

    Tonegawa, Motonari; Okada, Hiroyuki; Akiyama, Masayuki; Dalton, Gavin; Glazebrook, Karl; Iwamuro, Fumihide; Maihara, Toshinori; Ohta, Kouji; Shimizu, Ikkoh; Takato, Naruhisa; Tamura, Naoyuki; Yabe, Kiyoto; Bunker, Andrew J; Coupon, Jean; Ferreira, Pedro G; Frenk, Carlos S; Goto, Tomotsugu; Hikage, Chiaki; Ishikawa, Takashi; Matsubara, Takahiko; More, Surhud; Okumura, Teppei; Percival, Will J; Spitler, Lee R; Szapudi, Istvan

    2015-01-01

    FastSound is a galaxy redshift survey using the near-infrared Fiber Multi-Object Spectrograph (FMOS) mounted on the Subaru Telescope, targeting H$\\alpha$ emitters at $z \\sim 1.18$--$1.54$ down to the sensitivity limit of H$\\alpha$ flux $\\sim 2 \\times 10^{-16} \\ \\rm erg \\ cm^{-2} s^{-1}$. The primary goal of the survey is to detect redshift space distortions (RSD), to test General Relativity by measuring the growth rate of large scale structure and to constrain modified gravity models for the origin of the accelerated expansion of the universe. The target galaxies were selected based on photometric redshifts and H$\\alpha$ flux estimates calculated by fitting spectral energy distribution (SED) models to the five optical magnitudes of the Canada France Hawaii Telescope Legacy Survey (CFHTLS) Wide catalog. The survey started in March 2012, and all the observations were completed in July 2014. In total, we achieved $121$ pointings of FMOS (each pointing has a $30$ arcmin diameter circular footprint) covering $20.6...

  10. On the properties of galaxies at the faint-end of the H$\\alpha$ luminosity function at $z\\sim0.62$

    Gómez-Guijarro, Carlos; Villar, Víctor; Rodríguez-Muñoz, Lucía; Clément, Benjamin; Cuby, Jean-Gabriel

    2016-01-01

    Studies measuring the star formation rate density, luminosity function and properties of star-forming galaxies are numerous. However, it exists a gap at $0.5H$\\alpha$-based studies. Our main goal is to study the properties of a sample of faint H$\\alpha$ emitters at $z\\sim0.62$. We focus on their contribution to the faint-end of the luminosity function and derived star formation rate density, characterising their morphologies and basic photometric and spectroscopic properties. We use a narrow-band technique in the near-infrared, with a filter centered at 1.06 $\\mu$m. The data come from ultra-deep VLT/HAWK-I observations in the GOODS-S field with a total of 31.9 h in the narrow-band filter. We perform a visual classification of the sample and study their morphologies from structural parameters available in CANDELS. Our 28 H$\\alpha$-selected sample of faint star-forming galaxies reveals a robust faint-end slope of the luminosity function $\\alpha=-1.46_{-0.08}^{+0.16}$. The derived star formation...

  11. Politico-economic equivalence

    Gonzalez Eiras, Martin; Niepelt, Dirk

    2015-01-01

    Traditional "economic equivalence'' results, like the Ricardian equivalence proposition, define equivalence classes over exogenous policies. We derive "politico-economic equivalence" conditions that apply in environments where policy is endogenous and chosen sequentially. A policy regime and a...... state are equivalent to another such pair if both pairs give rise to the same allocation in politico-economic equilibrium. The equivalence conditions help to identify factors that render institutional change non-neutral and to construct politico-economic equilibria in new policy regimes. We exemplify...

  12. ?(1520) ? ?? Radiative-Decay Width

    The radiative decay ?(1520) ? ?? was recorded in the exclusive reaction p + N ? ?(1520)K+ + N at the SPHINX facility. The branching ratio for this decay and the corresponding partial width were found to be, respectively, Br[?(1520) ? ??] = (1.02 0.21) x 10-2 and ?[?(1520) ? ??] = 159 35 keV (the quoted errors are purely statistical, the systematic errors being within 15%)

  13. On the maximal diphoton width

    Salvio, Alberto; Staub, Florian; Strumia, Alessandro; Urbano, Alfredo

    2016-03-01

    Motivated by the 750 GeV diphoton excess found at LHC, we compute the maximal width into γγ that a neutral scalar can acquire through a loop of charged fermions or scalars as function of the maximal scale at which the theory holds, taking into account vacuum (meta)stability bounds. We show how an extra gauge symmetry can qualitatively weaken such bounds, and explore collider probes and connections with Dark Matter.

  14. Width of nonlinear difference resonances

    We consider an isolated difference resonance of the form (2p)ν1 - (2q)ν2 = n + epsilon where (2p) and (2q) are positive integers with (2p)+(2q)>2, n is 0 or an integer and exclamationepsilonexclamation1)P(2I2) /SUP q/ cos (/PHI/), /PHI/ =(2p)a1-(2q)a2 +const. Unlike sum resonances, two action variables I1 and I2, which are proportional to emittances in two directions, are bounded and any definition of resonance width will involve the concept of an ''acceptable'' growth in I1 or I2. We propose a definition such that inside the resonance width, an initial condition of large I2 and very small I1 will lead to an order of magnitude growth in I1. With this definition, the width is indefinite for (2p)=1. An arbitrarily small I1 can grow to a sizable fraction of (p/q)I2 for any value of exclamationepsilonexclamation. For (2p)=2, the width is proportional to D X (I2) /SUP q/ . One cannot have resonances for (2p)>2 according to this definition, but there is a threshold value of initial I1 above which I1 will grow by a large factor if exclamationepsilonexclamation and the invariant quantity I1+(p/q)I2 satisfy a certain relation which will be given analytically. We thus propose a definition involving one parameter for (2p)=2 and two for (2p)>2. The picture is clearly symmetric in two directions: if the initial I2 is very small and I1 large, one simply uses (2q) in place of (2p) to classify the resonances

  15. On the maximal diphoton width

    Salvio, Alberto(Departamento de Física Teórica, Universidad Autónoma de Madrid and Instituto de Física Teórica IFT-UAM/CSIC, Madrid, Spain); Staub, Florian; STRUMIA, Alessandro; Urbano, Alfredo(SISSA, via Bonomea 265, Trieste, I-34136 ITALY)

    2016-01-01

    Motivated by the 750 GeV diphoton excess found at LHC, we compute the maximal width into $\\gamma\\gamma$ that a neutral scalar can acquire through a loop of charged fermions or scalars as function of the maximal scale at which the theory holds, taking into account vacuum (meta)stability bounds. We show how an extra gauge symmetry can qualitatively weaken such bounds, and explore collider probes and connections with Dark Matter.

  16. An Equivalent Gauge and the Equivalence Theorem

    Wulzer, Andrea

    2014-01-01

    I describe a novel covariant formulation of massive gauge theories in which the longitudinal polarization vectors do not grow with the energy. Therefore in the present formalism, differently from the ordinary one, the energy and coupling power-counting is completely transparent at the level of individual Feynman diagrams, with obvious advantages both at the conceptual and practical level. Since power-counting is transparent, the high-energy limit of the amplitudes involving longitudinal particles is immediately taken, and the Equivalence Theorem is easily demonstrated at all orders in perturbation theory. Since the formalism makes the Equivalence Theorem self-evident, and because it is based on a suitable choice of the gauge, we can call it an "Equivalent Gauge".

  17. An Equivalent Gauge and the Equivalence Theorem

    I describe a novel covariant formulation of massive gauge theories in which the longitudinal polarization vectors do not grow with the energy. Therefore in the present formalism, differently from the ordinary one, the energy and coupling power-counting is completely transparent at the level of individual Feynman diagrams, with obvious advantages both at the conceptual and practical level. Since power-counting is transparent, the high-energy limit of the amplitudes involving longitudinal particles is immediately taken, and the Equivalence Theorem is easily demonstrated at all orders in perturbation theory. Since the formalism makes the Equivalence Theorem self-evident, and because it is based on a suitable choice of the gauge, we can call it an “Equivalent Gauge”

  18. Formation of Raman Scattering Wings around H alpha, H beta, and Pa alpha in Active Galactic Nuclei

    Chang, Seok-Jun; Heo, Jeong-Eun; Di Mille, Francesco; Angeloni, Rodolfo; Palma, Tali; Lee, Hee-Won

    2015-12-01

    Powered by a supermassive black hole with an accretion disk, the spectra of active galactic nuclei (AGNs) are characterized by prominent emission lines including Balmer lines. The unification schemes of AGNs require the existence of a thick molecular torus that may hide the broad emission line region from the view of observers near the equatorial direction. In this configuration, one may expect that the far-UV radiation from the central engine can be Raman scattered by neutral hydrogen to reappear around Balmer and Paschen emission lines, which can be identified with broad wings. We produce H?, H?, and Pa? wings using a Monte Carlo technique to investigate their properties. The neutral scattering region is assumed to be a cylindrical torus specified by the inner and outer radii and the height. While the covering factor of the scattering region affects the overall strengths of the wings, the wing widths are primarily dependent on the neutral hydrogen column density {N}{{H} {{I}}} being roughly proportional to {N}{{H} {{I}}}1/2. In particular, with {N}{{H} {{I}}}={10}23 {{cm}}-2 the H? wings typically show a width ? 2 {10}4 {km} {{{s}}}-1. We also find that H? and Pa? wing profiles are asymmetric with the red part stronger than the blue part and an opposite behavior is seen for H? wings.

  19. Characterization of revenue equivalence

    Heydenreich, Birgit; Müller, Rudolf; Uetz, Marc

    2007-01-01

    The property of an allocation rule to be implementable in dominant strategies by a unique payment scheme is called revenue equivalence. In this paper we give a characterization of revenue equivalence based on a graph theoretic interpretation of the incentive compatibility constraints. The characterization holds for any (possibly in¯nite) outcome space and many of the known results about revenue equivalence are immediate consequences.

  20. Ultra Low-Frequency Oscillations of a Solar Filament in H{\\alpha} Revealed With the Data of the Global Oscillation Network Group (Gong)

    Efremov, V I; Soloviev, A A

    2016-01-01

    The data of ground-based telescopes of Global Oscillation Network Group (GONG) obtained in the H-alpha line provide an opportunity to study the long-period oscillations of chromospheric filaments (quiescent prominence). For the first time, on the base of time-series of 5 days duration, combined from the observations of three observatories of the GONG, a new ultra-low mode, with period between 20 and 30 hours, was reliably detected in oscillations of a long-lived dark filament on the solar disc.

  1. Hydrodynamical and radiative modeling of temporal H{\\alpha} emission V/R variations caused by a discontinuous mass transfer in binaries

    Chadima, Pavel; Firt, Roman; Harmanec, Petr; Wolf, Marek; Ruzdjak, Domagoj; Bozic, Hrvoje; Koubsky, Pavel

    2011-01-01

    H{\\alpha} emission V/R variations caused by a discontinous mass transfer in interacting binaries with a rapidly rotating accreting star are modelled qualititatively for the first time. The program ZEUS-MP was used for a non-linear 3-D hydrodynamical modeling of a development of a blob of gaseous material injected into an orbit around a star. It resulted in the formation of an elongated disk with a slow prograde revolution. The LTE radiative transfer program SHELLSPEC was used to calculate the...

  2. Human osseous intervertebral foramen width.

    Rühli, F J; Müntener, M; Henneberg, M

    2006-02-01

    Alterations of the width of the human intervertebral foramen can play a pathophysiological role in low back pain. Osseous dimensions of the human intervertebral foramen are rarely recorded. Therefore, we present reference data obtained from skeletal samples of known lifestyle, population affinity, sex, and age at death. Cervical, thoracic, and lumbar vertebrae of functional transition zones of 71 macroscopically normal spines from early 19th century AD Swiss burial sites were selected. The intervertebral foramen widths (IFW) were analyzed with respect to possible lateralization and the impact of sex, individual age, and stature. Neither a significant side difference nor a correlation of IFW with individual age or stature could be found. Females show somewhat larger IFW than males, especially in the lumbar region. Data comparisons with earlier studies are limited due to methodological differences and possible interpopulational variations. Furthermore, the osseous intervertebral foramen only reveals a glimpse of the clinically relevant in vivo structure. Nevertheless, more focus on the osseous dimensions of the intervertebral foramen will provide baseline data of this important anatomical landmark. These data could also explore the peculiarities of the intervertebral foramen, such as its reverse sex dimorphism. PMID:16323199

  3. Inferred H{\\alpha} Flux as a Star-Formation Rate Indicator at z ~ 4-5: Implications for Dust Properties, Burstiness, and the z = 4-8 Star-Formation-Rate Functions

    Smit, Renske; Labb, Ivo; Franx, Marijn; Wilkins, Stephen M; Oesch, Pascal A

    2015-01-01

    We derive H{\\alpha} fluxes for a large spectroscopic and photometric-redshift-selected sample of sources over GOODS-North and South in the redshift range z = 3.8-5.0 with deep HST, Spitzer/IRAC, and ground-based observations. The H{\\alpha} flux is inferred based on the offset between the IRAC 3.6 {\\mu}m flux and that predicted from the best-fit SED. We demonstrate that the H{\\alpha} flux correlates well with dust- corrected UV star-formation rate (SFR) and therefore can serve as an independent SFR indicator. However, we also find a systematic offset in the SFR_H{\\alpha}/SFR_UV ratios for z ~ 4-5 galaxies relative to local relations (assuming the same dust corrections for nebular regions and stellar light). We show that we can resolve the modest tension in the inferred SFRs by assuming bluer intrinsic UV slopes (increasing the dust correction), a rising star-formation history or assuming a low metallicity stellar population with a hard ionizing spectrum (increasing the L_H{\\alpha}/SFR ratio). Using H{\\alpha} a...

  4. Geodesic equivalence and integrability

    Topalov, Petar J.; Vladimir S. Matveev

    1999-01-01

    We suggest a construction that, given a trajectorial diffeomorphism between two Hamiltonian systems, produces integrals of them. As the main example we treat geodesic equivalence of metrics. We show that the existence of a non-trivially geodesically equivalent metric leads to Liouville integrability, and present explicit formulae for integrals.

  5. Narrow-width approximation accuracy

    A study of general properties of the narrow-width approximation (NWA) with polarization/spin decorrelation is presented. We prove for sufficiently inclusive differential rates of arbitrary resonant decay or scattering processes with an on-shell intermediate state decaying via a cubic or quartic vertex that decorrelation effects vanish and the NWA is of order Γ. Its accuracy is then determined numerically for all resonant 3-body decays involving scalars, spin-1/2 fermions or vector bosons. We specialize the general results to MSSM benchmark scenarios. Significant off-shell corrections can occur - similar in size to QCD corrections. We qualify the configurations in which a combined consideration is advisable. For this purpose, we also investigate process-independent methods to improve the NWA

  6. Macroclumping as solution of the discrepancy between H{\\alpha} and P v mass loss diagnostics for O-type stars

    Šurlan, B; Aret, A; Kubát, J; Oskinova, L M; Torres, A F

    2013-01-01

    Recent studies of O-type stars demonstrated that discrepant mass-loss rates are obtained when different diagnostic methods are employed - fitting the unsaturated UV resonance lines (e.g. P v) gives drastically lower values than obtained from the H{\\alpha} emission. Wind clumping may be the main cause for this discrepancy. In a previous paper, we have presented 3-D Monte-Carlo calculations for the formation of scattering lines in a clumped stellar wind. In the present paper we select five O-type supergiants (from O4 to O7) and test whether the reported discrepancies can be resolved this way. In the first step, the analyses start with simulating the observed spectra with Potsdam Wolf-Rayet (PoWR) non-LTE model atmospheres. The mass-loss rates are adjusted to fit best to the observed H{\\alpha} emission lines. For the unsaturated UV resonance lines (i.e. P v) we then apply our 3-D Monte-Carlo code, which can account for wind clumps of any optical depths, a non-void inter-clump medium, and a velocity dispersion in...

  7. Development of an Advanced Automated Method for Solar Filament Recognition and Its Scientific Application to a Solar Cycle of MLSO H\\alpha\\ Data

    Hao, Qi; Chen, P F

    2013-01-01

    We developed a method to automatically detect and trace solar filaments in H\\alpha\\ full-disk images. The program is able not only to recognize filaments and determine their properties, such as the position, the area, the spine, and other relevant parameters, but also to trace the daily evolution of the filaments. The program consists of three steps: First, preprocessing is applied to correct the original images; Second, the Canny edge-detection method is used to detect filaments; Third, filament properties are recognized through the morphological operators. To test the algorithm, we applied it to the observations from the Mauna Loa Solar Observatory (MLSO), and the program is demonstrated to be robust and efficient. H\\alpha\\ images obtained by MLSO from 1998 to 2009 are analyzed, and a butterfly diagram of filaments is obtained. It shows that the latitudinal migration of solar filaments has three trends in the Solar Cycle 23: The drift velocity was fast from 1998 to the solar maximum; After the solar maximum...

  8. GHASP: an H$\\alpha$ kinematic survey of spiral galaxies - X. Surface photometry, decompositions and the Tully-Fisher relation in the Rc-band

    Barbosa, C E; Amram, P; Ferrari, F; Russeil, D; Epinat, B; Perret, V; Adami, C; Marcelin, M

    2015-01-01

    We present Rc-band surface photometry for 170 of the 203 galaxies in GHASP, Gassendi H-Alpha survey of SPirals, a sample of late-type galaxies for which high-resolution Fabry-Perot H{\\alpha} maps have previously been obtained. Our data set is constructed by new Rc-band observations taken at the Observatoire de Haute-Provence (OHP), supplemented with Sloan Digital Sky Survey (SDSS) archival data, obtained with the purpose of deriving homogeneous photometric profiles and parameters. Our results include Rc-band surface brightness profiles for 170 galaxies and $ugriz$ profiles for 108 of these objects. We catalogue several parameters of general interest for further reference, such as total magnitude, effective radius and isophotal parameters -- magnitude, position angle, ellipticity and inclination. We also perform a structural decomposition of the surface brightness profiles using a multi-component method in order to separate disks from bulges and bars, and to observe the main scaling relations involving luminos...

  9. A very young, compact bipolar H$_2$O maser outflow in the intermediate-mass star-forming LkH$\\alpha$ 234 region

    Torrelles, J M; Estalella, R; Anglada, G; Gómez, J F; Cantó, J; Patel, N A; Trinidad, M A; Girart, J M; Carrasco-González, C; Rodríguez, L F

    2014-01-01

    We report multi-epoch VLBI H$_2$O maser observations towards the compact cluster of YSOs close to the Herbig Be star LkH$\\alpha$ 234. This cluster includes LkH$\\alpha$ 234 and at least nine more YSOs that are formed within projected distances of $\\sim$10 arcsec ($\\sim$9,000 au). We detect H$_2$O maser emission towards four of these YSOs. In particular, our VLBI observations (including proper motion measurements) reveal a remarkable very compact ($\\sim$0.2 arcsec = $\\sim$180 au), bipolar H$_2$O maser outflow emerging from the embedded YSO VLA 2. We estimate a kinematic age of $\\sim$40 yr for this bipolar outflow, with expanding velocities of $\\sim$20 km s$^{-1}$ and momentum rate $\\dot M_w V_w$ $\\simeq$ $10^{-4}-10^{-3}$ M$_{\\odot}$ yr$^{-1}$ km s$^{-1}$$\\times (\\Omega$/$4\\pi)$, powered by a YSO of a few solar masses. We propose that the outflow is produced by recurrent episodic jet ejections associated with the formation of this YSO. Short-lived episodic ejection events have previously been found towards high...

  10. A Study of the Distribution of Star-Forming Regions in Luminous Infrared Galaxies by Means of H$\\alpha$ Imaging Observations

    Hattori, T; Ohtani, H; Sugai, H; Ishigaki, T; Sasaki, M; Hayashi, T; Ozaki, S; Ishii, M; Kawai, A

    2003-01-01

    We performed H-alpha imaging observations of 22 luminous infrared galaxies to investigate how the distribution of star-forming regions in these galaxies is related to galaxy interactions. Based on correlation diagrams between H-alpha flux and continuum emission for individual galaxies, a sequence for the distribution of star-forming regions was found: very compact (~100 pc) nuclear starbursts with almost no star-forming activity in the outer regions (type 1), dominant nuclear starbursts 1 kpc in size and a significant contribution from the outer regions (type 3), and extended starbursts with relatively faint nuclei (type 4). These classes of star-forming region were found to be strongly related to global star-forming properties such as star-formation efficiency, far-infrared color, and dust extinction. There was a clear tendency for the objects with more compact distributions of star-forming regions to show a higher star-formation efficiency and hotter far-infrared color. An appreciable fraction of the sampl...

  11. The MOSDEF Survey: The strong agreement between H-alpha and UV-to-FIR star formation rates for z~2 star-forming galaxies

    Shivaei, Irene; Reddy, Naveen A; Shapley, Alice E; Barro, Guillermo; Conroy, Charlie; Coil, Alison L; Freeman, William R; Mobasher, Bahram; Siana, Brian; Sanders, Ryan; Price, Sedona H; Azadi, Mojegan; Pasha, Imad; Inami, Hanae

    2016-01-01

    We present the first direct comparison between Balmer line and panchromatic SED-based SFRs for z~2 galaxies. For this comparison we used 17 star-forming galaxies selected from the MOSFIRE Deep Evolution Field (MOSDEF) survey, with $3\\sigma$ detections for H$\\alpha$ and at least two IR bands (Spitzer/MIPS 24$\\mu$m and Herschel/PACS 100 and 160$\\mu$m, and in some cases Herschel/SPIRE 250, 350, and 500$\\mu$m). The galaxies have total IR (8-1000$\\mu$m) luminosities of $\\sim10^{11.4}-10^{12.4}\\,\\textrm{L}_\\odot$ and star-formation rates (SFRs) of $\\sim30-250\\,\\textrm{M}_\\odot\\,\\mathrm{yr^{-1}}$. We fit the UV-to-far-IR SEDs with flexible stellar population synthesis (FSPS) models - which include both stellar and dust emission - and compare the inferred SFRs with the SFR(H$\\alpha$,H$\\beta$) values corrected for dust attenuation using Balmer decrements. The two SFRs agree with a scatter of 0.17 dex. Our results imply that the Balmer decrement accurately predicts the obscuration of the nebular lines and can be used t...

  12. Heteronuclear relayed E.COSY revisited: determination of 3J(H(alpha),C(gamma)) couplings in Asx and aromatic residues in proteins.

    Löhr, F; Pérez, C; Köhler, R; Rüterjans, H; Schmidt, J M

    2000-09-01

    Constant-time 3D heteronuclear relayed E.COSY [Schmidt et al. (1996) J. Biomol. NMR, 7, 142-152], as based on generic 2D small-flip-angle HMQC-COSY [Schmidt et al. (1995) J. Biomol. NMR, 6, 95-105], has been modified to allow for quantitative determination of heteronuclear three-bond 3J(H(alpha),C(gamma)) couplings. The method is applicable to amino acid spin topologies with carbons in the gamma position which lack attached protons, i.e. to asparagine, aspartate, and aromatic residues in uniformly 13C-enriched proteins. The pulse sequence critically exploits heteronuclear triple-quantum coherence (HTQC) of CH2 moieties involving geminal H(beta) proton pairs, taking advantage of improved multiple-quantum relaxation properties, at the same time avoiding scalar couplings between those spins involved in multiple-quantum coherence, thus yielding E.COSY-type multiplets with a splitting structure that is simpler than with the original scheme. Numerical least-squares 2D line-shape simulation is used to extract 3J(H(alpha),C(gamma)) coupling constants which are of relevance to side-chain chi1 dihedral-angle conformations in polypeptides. Methods are demonstrated with recombinant 15N,13C-enriched ribonuclease T1 and Desulfovibrio vulgaris flavodoxin with bound oxidized FMN. PMID:11061224

  13. The environmental impacts on the star formation main sequence: an H-alpha study of the newly discovered rich cluster at z=1.52

    Koyama, Yusei; Tadaki, Ken-ichi; Hayashi, Masao; Tanaka, Ichi; Shimakawa, Rhythm

    2014-01-01

    We report the discovery of a strong over-density of galaxies in the field of a radio galaxy at z=1.52 (4C65.22) based on our broad-band and narrow-band (H-alpha) photometry with Subaru Telescope. We find that H-alpha emitters are located in the outskirts of the density peak (cluster core) dominated by passive red-sequence galaxies. This resembles the situation in lower-redshift clusters, suggesting that the newly discovered structure is a well-evolved rich galaxy cluster at z=1.5. Our data suggest that the color-density and stellar mass-density relations are already in place at z~1.5, mostly driven by the passive red massive galaxies residing within Rc<200 kpc from the cluster core. These environmental trends almost disappear when we consider only star-forming (SF) galaxies. We do not find SFR-density or SSFR-density relations amongst SF galaxies, and the location of the SF main sequence does not significantly change with environment. Nevertheless, we find a tentative hint that star-bursting galaxies (up-s...

  14. Comparing H-alpha and HI Surveys as Means to a Complete Local Galaxy Catalog in the Advanced LIGO/Virgo Era

    Metzger, Brian D; Berger, Edo

    2012-01-01

    Identifying the electromagnetic counterparts of gravitational wave (GW) sources detected by upcoming networks of advanced ground-based interferometers will be challenging due in part to the large number of unrelated astrophysical transients within the ~10-100 square degree sky localizations. A potential way to greatly reduce the number of such false positives is to limit detailed follow-up to only those candidates near galaxies within the GW sensitivity range of ~200 Mpc for binary neutron star mergers. Such a strategy is currently hindered by the fact that galaxy catalogs are grossly incomplete within this volume. Here we compare two methods for completing the local galaxy catalog: (1) a narrow-band H-alpha imaging survey; and (2) an HI emission line radio survey. Using H-alpha fluxes, stellar masses (M_star), and star formation rates (SFR) from galaxies in the Sloan Digital Sky Survey (SDSS), combined with HI data from the GALEX Arecibo SDSS Survey and the Herschel Reference Survey, we estimate that a H-alp...

  15. A Study of Selection Methods for H alpha Emitting Galaxies at z~1.3 for the Subaru/FMOS Galaxy Redshift Survey for Cosmology (FastSound)

    Tonegawa, Motonari; Akiyama, Masayuki; Dalton, Gavin; Glazebrook, Karl; Iwamuro, Fumihide; Sumiyoshi, Masanao; Tamura, Naoyuki; Yabe, Kiyoto; Coupon, Jean; Goto, Tomotsugu; Spitler, Lee R

    2013-01-01

    The efficient selection of high-redshift emission galaxies is important for future large galaxy redshift surveys for cosmology. Here we describe the target selection methods for the FastSound project, a redshift survey for H alpha emitting galaxies at z=1.2-1.5 using Subaru/FMOS to measure the linear growth rate f\\sigma 8 via Redshift Space Distortion (RSD) and constrain the theory of gravity. To select ~400 target galaxies in the 0.2 deg^2 FMOS field-of-view from photometric data of CFHTLS-Wide (u*g'r'i'z'), we test several different methods based on color-color diagrams or photometric redshift estimates from spectral energy distribution (SED) fitting. We also test the improvement in selection efficiency that can be achieved by adding near-infrared data from the UKIDSS DXS (J). The success rates of H alpha detection with FMOS averaged over two observed fields using these methods are 11.3% (color-color, optical), 13.6% (color-color, optical+NIR), 17.3% (photo-z, optical), and 15.1% (photo-z, optical+NIR). Sel...

  16. Constraining the Age and Distance of the Galactic Supernova Remnant G156.2+5.7 by H-alpha Expansion Measurements

    Katsuda, Satoru; Morokuma, Tomoki; Fesen, Robert; Milisavljevic, Dan

    2016-01-01

    We present deep H-alpha images of portions of the X-ray bright but optically faint Galactic supernova remnant G156.2+5.7, revealing numerous and delicately thin nonradiative filaments which mark the location of the remnant's forward shock. These new images show that these filaments have a complex structure not visible on previous lower resolution optical images. By comparing H-alpha images taken in 2004 at the McDonald Observatory and in 2015-2016 at the Kiso Observatory, we set a stringent 1-sigma upper limit of expansion to be 0.06 arcsec/yr. This proper motion, combined with a shock speed of 500 km/s inferred from X-ray spectral analyses, gives a distance of > 1.7 kpc. In addition, a simple comparison of expansion indices of several SNRs allows us to infer the age of the remnant to be a few 10,000 yr old. These estimates are more straightforward and reliable than any other previous studies, and clearly rule out a possibility that G156.2+5.7 is physically associated with part of the Taurus-Auriga cloud and ...

  17. The narrow X-ray tail and double H-alpha tails of ESO 137-002 in Abell 3627

    Zhang, B; Ji, L; Sarazin, C; Lin, X B; Nulsen, P E J; Roediger, E; Donahue, M; Forman, W; Jones, C; Voit, G M; Kong, X

    2013-01-01

    We present the analysis of a deep Chandra observation of a ~2L_* late-type galaxy, ESO 137-002, in the closest rich cluster A3627. The Chandra data reveal a long (>40 kpc) and narrow tail with a nearly constant width (~3 kpc) to the southeast of the galaxy, and a leading edge ~1.5 kpc from the galaxy center on the upstream side of the tail. The tail is most likely caused by the nearly edge-on stripping of ESO 137-002's ISM by ram pressure, compared to the nearly face-on stripping of ESO 137-001 discussed in our previous work. Spectral analysis of individual regions along the tail shows that the gas throughout it has a rather constant temperature, ~1 keV, very close to the temperature of the tails of ESO 137-001, if the same atomic database is used. The derived gas abundance is low (~0.2 solar with the single-kT model), an indication of the multiphase nature of the gas in the tail. The mass of the X-ray tail is only a small fraction (<5%) of the initial ISM mass of the galaxy, suggesting that the stripping ...

  18. Topics in orbit equivalence

    Kechris, Alexander S

    2004-01-01

    This volume provides a self-contained introduction to some topics in orbit equivalence theory, a branch of ergodic theory. The first two chapters focus on hyperfiniteness and amenability. Included here are proofs of Dye's theorem that probability measure-preserving, ergodic actions of the integers are orbit equivalent and of the theorem of Connes-Feldman-Weiss identifying amenability and hyperfiniteness for non-singular equivalence relations. The presentation here is often influenced by descriptive set theory, and Borel and generic analogs of various results are discussed. The final chapter is a detailed account of Gaboriau's recent results on the theory of costs for equivalence relations and groups and its applications to proving rigidity theorems for actions of free groups.

  19. Planar Equivalence 2006

    Armoni, Adi(Department of Physics, Swansea University Singleton Park, Swansea, SA2 8PP, UK); Shifman, M.

    2007-01-01

    Planar equivalence between supersymmetric Yang--Mills theory and its orientifold daughters is a promising tool for explorations of nonperturbative aspects of quantum chromodynamics. Taking our 2004 review as a starting point we summarize some recent developments in this issue.

  20. Phage pilH alpha: a phage which adsorbs to IncHI and IncHII plasmid-coded pili.

    Coetzee, J N; Bradley, D E; Fleming, J; du Toit, L; Hughes, V M; Hedges, R W

    1985-05-01

    Phage pilH alpha was specific for bacterial strains, of various genera, harbouring plasmids of the HI and HII incompatibility groups. Plaque formation was temperature sensitive in that plaques formed at 26 degrees C but not at 37 degrees C. Plaques were fairly clear, irregular in outline and varied from pin point to about 2 mm in diameter on all hosts where plaques were detected. The phage had an isometric hexagonal outline with a diameter of 25 nm. It contained RNA but differed from all but one other plasmid-dependent RNA phage by being sensitive to chloroform. It adsorbed along the length of the shafts of IncHI and HII plasmid-coded pili. PMID:2862220

  1. Gluing derived equivalences together

    Asashiba, Hideto

    2012-01-01

    The Grothendieck construction of a diagram X of categories can be seen as a process to construct a single category Gr(X) by gluing categories in the diagram together. Here we formulate diagrams of categories as oplax functors from a small category I to the 2-category k-Cat of small k-categories for a fixed commutative ring k. In our previous paper we defined derived equivalences of those oplax functors. Roughly speaking two oplax functors X, X' : I \\to k-Cat are derived equivalent if there exist a family of triangle equivalences F(i) from the derived categories D(Mod X(i)) to D(Mod X'(i)) indexed by the objects i in I such that for each morphism a : i \\to j in I F(j)D(Mod X)(a) is naturally isomorphic to D(Mod X')(a)F(i), where D(Mod X)(a) : D(Mod X(i)) \\to D(Mod X'(i)) is given by the left derived tensor product with an X(i)-X'(i)-bimodule \\bar{X(a)} naturally defined by the functor X(a) : X(i) \\to X(j). In this paper we glue the derived equivalences F(i) together to obtain a derived equivalence between Grot...

  2. Effects of the $\\gamma-$rays Scattered Backward by Metals on the Nuclear Energy Level Width

    Cheon, I T; Cheon, Il-Tong; Jeong, Moon Taeg

    2006-01-01

    By placing a ${}^{133}Cs$ $\\gamma$-ray source embedded in a solid at the center of a platinum (gold) cylinder, we try to change the width of the 81-keV level. Our results show a narrowed energy level and, equivalently, a prolonged lifetime. With a 0.5-mm-thick, 5-cm-long, 2-mm-diameter platinum cylinder, we obtain a width narrower by $6.1 % $ at $4.2 \\: K$.

  3. Establishing Substantial Equivalence: Transcriptomics

    Baudo, María Marcela; Powers, Stephen J.; Mitchell, Rowan A. C.; Shewry, Peter R.

    Regulatory authorities in Western Europe require transgenic crops to be substantially equivalent to conventionally bred forms if they are to be approved for commercial production. One way to establish substantial equivalence is to compare the transcript profiles of developing grain and other tissues of transgenic and conventionally bred lines, in order to identify any unintended effects of the transformation process. We present detailed protocols for transcriptomic comparisons of developing wheat grain and leaf material, and illustrate their use by reference to our own studies of lines transformed to express additional gluten protein genes controlled by their own endosperm-specific promoters. The results show that the transgenes present in these lines (which included those encoding marker genes) did not have any significant unpredicted effects on the expression of endogenous genes and that the transgenic plants were therefore substantially equivalent to the corresponding parental lines.

  4. Supersymmetric decay widths of weak bosons

    The partial widths of W and Z decays to supersymmetric particles are evaluated in the simplest N = 1 supergravity model. The total widths can be 50% greater than the standard-model predictions. Measurements of the widths at the p-barp collider can thereby be used either to place improved lower limits on gaugino, scalar-quark, and scalar-lepton masses or to provide indirect evidence for supersymmetry

  5. Influence of MLC leaf width on biologically adapted IMRT plans

    Introduction. High resolution beam delivery may be required for optimal biology-guided adaptive therapy. In this work, we have studied the influence of multi leaf collimator (MLC) leaf widths on the treatment outcome following adapted IMRT of a hypoxic tumour. Material and methods. Dynamic contrast enhanced MR images of a dog with a spontaneous tumour in the nasal region were used to create a tentative hypoxia map following a previously published procedure. The hypoxia map was used as a basis for generating compartmental gross tumour volumes, which were utilised as planning structures in biologically adapted IMRT. Three different MLCs were employed in inverse treatment planning, with leaf widths of 2.5 mm, 5 mm and 10 mm. The number of treatment beams and the degree of step-and-shoot beam modulation were varied. By optimising the tumour control probability (TCP) function, optimal compartmental doses were derived and used as target doses in the inverse planning. Resulting IMRT dose distributions and dose volume histograms (DVHs) were exported and analysed, giving estimates of TCP and compartmental equivalent uniform doses (EUDs). The impact of patient setup accuracy was simulated. Results. The MLC with the smallest leaf width (2.5 mm) consistently gave the highest TCPs and compartmental EUDs, assuming no setup error. The difference between this MLC and the 5 mm MLC was rather small, while the MLC with 10 mm leaf width gave considerably lower TCPs. When including random and systematic setup errors, errors larger than 5 mm gave only small differences between the MLC types. For setup errors larger than 7 mm no differences were found between non-uniform and uniform dose distributions. Conclusions. Biologically adapted radiotherapy may require MLCs with leaf widths smaller than 10 mm. However, for a high probability of cure it is crucial that accurate patient setup is ensured.

  6. Equivalent Quantum Circuits

    Garcia-Escartin, Juan Carlos

    2011-01-01

    Quantum algorithms and protocols are often presented as quantum circuits for a better understanding. We give a list of equivalence rules which can help in the analysis and design of quantum circuits. As example applications we study quantum teleportation and dense coding protocols in terms of a simple XOR swapping circuit and give an intuitive picture of a basic gate teleportation circuit.

  7. Understanding Equivalent Fractions.

    Hunting, Robert P.

    1984-01-01

    Twenty-nine students in grades four, six, and eight were asked to find solutions to fraction equivalence problems and to verify their solutions using discrete material. Discontinuities were observed between strategies students used for producing solutions and supporting knowledge grounded in physical reality. (Author/MNS)

  8. Correspondences. Equivalence relations

    We comment on sections paragraph 3 'Correspondences' and paragraph 6 'Equivalence Relations' in chapter II of 'Elements de mathematique' by N. Bourbaki in order to simplify their comprehension. Paragraph 3 exposes the ideas of a graph, correspondence and map or of function, and their composition laws. We draw attention to the following points: 1) Adopting the convention of writting from left to right, the composition law for two correspondences (A,F,B), (U,G,V) of graphs F, G is written in full generality (A,F,B)o(U,G,V) = (A,FoG,V). It is not therefore assumed that the co-domain B of the first correspondence is identical to the domain U of the second (EII.13 D.7), (1970). 2) The axiom of choice consists of creating the Hilbert terms from the only relations admitting a graph. 3) The statement of the existence theorem of a function h such that f = goh, where f and g are two given maps having the same domain (of definition), is completed if h is more precisely an injection. Paragraph 6 considers the generalisation of equality: First, by 'the equivalence relation associated with a map f of a set E identical to (x is a member of the set E and y is a member of the set E and x:f = y:f). Consequently, every relation R(x,y) which is equivalent to this is an equivalence relation in E (symmetrical, transitive, reflexive); then R admits a graph included in E x E, etc. Secondly, by means of the Hilbert term of a relation R submitted to the equivalence. In this last case, if R(x,y) is separately collectivizing in x and y, theta(x) is not the class of objects equivalent to x for R (EII.47.9), (1970). The interest of bringing together these two subjects, apart from this logical order, resides also in the fact that the theorem mentioned in 3) can be expressed by means of the equivalence relations associated with the functions f and g. The solutions of the examples proposed reveal their simplicity

  9. Computational study on reliability of sheath width measurement by the cutoff probe in low pressure plasmas

    Kim, D.-W.; You, S.-J.; Kim, J.-H.; Seong, D.-J.; Chang, H.-Y.; Oh, W.-Y.

    2015-11-01

    Recently, the technique for measurement of the sheath width by using the cutoff probe and its equivalent circuit model was proposed and conducted experimentally. In this study, we investigate the reliability of this technique based on the computational simulation. The simulation of three-dimensional Finite-Difference Time-Domain reproduces the transmission spectrum of the cutoff probe with an input parameter of sheath width. We measure the sheath width by using the circuit model and calculate the discrepancy between them under various input plasma densities and sheath widths. The results show the acceptable discrepancy under all of the conditions we studied (the largest discrepancy is about 45%). This indicates that the technique for measurement of sheath width around the floating tip of cutoff probe is robust and reliable. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

  10. Alliances and Bisection Width for Planar Graphs

    Olsen, Martin; Revsbk, Morten

    polynomial time. We base this on a proof of an upper bound of n on the bisection width for 4-connected planar graphs with an odd number of vertices. This improves a recently published n?+?1 upper bound on the bisection width of planar graphs without separating triangles and supports the folklore conjecture...

  11. Equivalence of Wilson actions

    Sonoda, H.

    2015-01-01

    We introduce the concept of equivalence among Wilson actions. Applying the concept to a real scalar theory on a euclidean space, we derive the exact renormalization group transformation of K. G. Wilson, and give a simple proof of universality of the critical exponents at any fixed point of the exact renormalization group transformation. We also show how to reduce the original formalism of Wilson to the simplified formalism by J. Polchinski.

  12. Equivalence Relations of -Algebra Extensions

    Changguo Wei

    2010-04-01

    In this paper, we consider equivalence relations of *-algebra extensions and describe the relationship between the isomorphism equivalence and the unitary equivalence. We also show that a certain group homomorphism is the obstruction for these equivalence relations to be the same.

  13. Statistical Analysis of Filament Features Based on the H{\\alpha} Solar Images from 1988 to 2013 by Computer Automated Detection Method

    Hao, Q; Cao, W; Chen, P F

    2015-01-01

    We improve our filament automated detection method which was proposed in our previous works. It is then applied to process the full disk H$\\alpha$ data mainly obtained by Big Bear Solar Observatory (BBSO) from 1988 to 2013, spanning nearly 3 solar cycles. The butterfly diagrams of the filaments, showing the information of the filament area, spine length, tilt angle, and the barb number, are obtained. The variations of these features with the calendar year and the latitude band are analyzed. The drift velocities of the filaments in different latitude bands are calculated and studied. We also investigate the north-south (N-S) asymmetries of the filament numbers in total and in each subclass classified according to the filament area, spine length, and tilt angle. The latitudinal distribution of the filament number is found to be bimodal. About 80% of all the filaments have tilt angles within [0{\\deg}, 60{\\deg}]. For the filaments within latitudes lower (higher) than 50{\\deg} the northeast (northwest) direction i...

  14. The nature of H-alpha star-forming galaxies at z~0.4 in and around Cl 0939+4713: the environment matters

    Sobral, David; Koyama, Yusei; Darvish, Behnam; Calhau, João; Afonso, Ana; Kodama, Tadayuki; Nakata, Fumiaki

    2016-01-01

    Cluster star-forming galaxies are found to have an excess of Far-Infrared emission relative to H-alpha (Ha), when compared to those in the field, which could be caused by intense AGN activity, dust and/or declining star formation histories. Here we present spectroscopic observations of Ha emitters in the Cl 0939+4713 (Abell 851) super-cluster at z=0.41, using AF2+WYFFOS on the WHT. We measure [OII], Hbeta (Hb), [OIII], Ha and [NII] for a sample of 119 Ha emitters in and around the cluster. We find that 17+-5% of the Ha emitters are AGN, irrespective of environment. For star-forming galaxies, we obtain Balmer decrements, metallicities and ionisation parameters with different methods, individually and by stacking. We find a strong mass-metallicity relation at all environments, with no significant dependence on environment. The ionisation parameter declines with increasing stellar mass for low-mass galaxies. Ha emitters residing in intermediate environments show the highest ionisation parameters (along with high...

  15. Study of LINER sources with broad H(alpha) emission. X-ray properties and comparision to luminous AGN and X-ray binaries

    George, Younes; Sabra, B; Reeves, J N

    2011-01-01

    [Abridged]We study the X-ray properties of LINER sources with definite detection of a broad H(alpha) emission line in their optical spectra, LINER 1s from Ho et al. sample. These objects preferentially harbor a low luminosity active nucleus at the center and show small or no intrinsic absorption (<10^(22) cm^(-1)). We analyzed all available X-ray archived XMM-Newton and Chandra observations of 13 LINER 1s satisfying the above criterion in a systematic homogeneous way. We looked for any correlations between the X-ray properties and the intrinsic parameters of our sample of LINER 1s. An absorbed power-law gave a good fit to the spectra of 9 out of the 13 sources. A thermal component and an absorbed power-law were required in the remaining 4 sources. We found a photon index between 1.3\\pm0.2 for the hardest source and 2.4^(+0.2)_(-0.3) for the softest one with a mean value of 1.9\\pm0.2 and a dispersion sigma=0.3. The thermal component had a mean temperature kT~0.6 keV. Significant short (hours to days) time-s...

  16. Bipartite Graphs of Large Clique-Width

    Korpelainen, Nicholas; Lozin, Vadim V.

    Recently, several constructions of bipartite graphs of large clique-width have been discovered in the literature. In the present paper, we propose a general framework for developing such constructions and use it to obtain new results on this topic.

  17. Direct measurement of the W boson width

    This Letter describes a direct measurement of the W boson decay width, Γ(W), using the high-mass tail of the transverse mass spectrum of W→eν decays recorded by the Collider Detector at Fermilab. We find Γ(W)=2.11±0.28(stat) ± 0.16(syst) GeV and compare this direct measurement with indirect means of obtaining the width

  18. Infinite-dimensional generalization of Kolmogorov widths

    Kounchev, Ognyan

    2011-01-01

    Recently the theory of widths of Kolmogorov-Gelfand has received a great deal of interest due to its close relationship with the newly born area of Compressive Sensing in Signal Processing. However fundamental problems of the theory of widths in multidimensional Theory of Functions remain untouched, as well as analogous problems in the theory of multidimensional Signal Analysis. In the present paper we provide a multidimensional generalization of the original result of Kolmogorov about the wi...

  19. Establishing Substantial Equivalence: Proteomics

    Lovegrove, Alison; Salt, Louise; Shewry, Peter R.

    Wheat is a major crop in world agriculture and is consumed after processing into a range of food products. It is therefore of great importance to determine the consequences (intended and unintended) of transgenesis in wheat and whether genetically modified lines are substantially equivalent to those produced by conventional plant breeding. Proteomic analysis is one of several approaches which can be used to address these questions. Two-dimensional PAGE (2D PAGE) remains the most widely available method for proteomic analysis, but is notoriously difficult to reproduce between laboratories. We therefore describe methods which have been developed as standard operating procedures in our laboratory to ensure the reproducibility of proteomic analyses of wheat using 2D PAGE analysis of grain proteins.

  20. Stuttering Equivalence for Parity Games

    Cranen, Sjoerd; Willemse, Tim A C

    2011-01-01

    We study the process theoretic notion of stuttering equivalence in the setting of parity games. We demonstrate that stuttering equivalent vertices have the same winner in the parity game. This means that solving a parity game can be accelerated by minimising the game graph with respect to stuttering equivalence. While, at the outset, it might not be clear that this strategy should pay off, our experiments using typical verification problems illustrate that stuttering equivalence speeds up solving parity games in many cases.

  1. Stuttering Equivalence for Parity Games

    Cranen, Sjoerd; Keiren, Jeroen J. A.; Willemse, Tim A. C.

    2011-01-01

    We study the process theoretic notion of stuttering equivalence in the setting of parity games. We demonstrate that stuttering equivalent vertices have the same winner in the parity game. This means that solving a parity game can be accelerated by minimising the game graph with respect to stuttering equivalence. While, at the outset, it might not be clear that this strategy should pay off, our experiments using typical verification problems illustrate that stuttering equivalence speeds up sol...

  2. An automated procedure for the assignment of protein 1HN, 15N, 13C alpha, 1H alpha, 13C beta and 1H beta resonances.

    Friedrichs, M S; Mueller, L; Wittekind, M

    1994-09-01

    A computer algorithm that determines the 1HN, 15N, 13C alpha, 1H alpha, 13C beta and 1H beta chemical-shift assignments of protein residues with minimal human intervention is described. The algorithm is implemented as a suite of macros that run under a modified version of the FELIX 1.0 program (Hare Research, Bothell, WA). The input to the algorithm is obtained from six multidimensional, triple-resonance experiments: 3D HNCACB, 3D CBCA(CO)HN, 4D HNCAHA, 4D HN(CO)CAHA, 3D HBHA(CO)NH and 3D HNHA(Gly). For small proteins, the two 4D spectra can be replaced by either the 3D HN(CA)HA, 3D H(CA)NNH, or the 15N-edited TOCSY-HSQC experiments. The algorithm begins by identifying and collecting the intraresidue and sequential resonances of the backbone and 13C beta atoms into groups. These groups are sequentially linked and then assigned to residues by matching the 13C alpha and 13C beta chemical-shift profiles of the linked groups to that of the protein's primary structure. A major strength of the algorithm is its ability to overcome imperfect data, e.g., missing or overlapping peaks. The viability of the procedure is demonstrated with two test cases. In the first, NMR data from the six experiments listed above were used to reassign the backbone resonances of the 93-residue human hnRNP C RNA-binding domain. In the second, a simulated cross-peak list, generated from the published NMR assignments of calmodulin, was used to test the ability of the algorithm to assign the backbone resonances of proteins containing internally homologous segments. Finally, the automated method was used to assign the backbone resonances of apokedarcidin, a previously unassigned, 114-residue protein. PMID:7919955

  3. The Variable Line Width of Achernar

    Rivinius, Th; Baade, D; Carciofi, A C; Leister, N; Štefl, S

    2016-01-01

    Spectroscopic observations of Achernar over the past decades, have shown the photospheric line width, as measured by the rotational parameter $v \\sin i$, to vary in correlation with the emission activity. Here we present new observations, covering the most recent activity phase, and further archival data collected from the archives. The $v \\sin i$ variation is confirmed. On the basis of the available data it cannot be decided with certainty whether the increased line width precedes the emission activity, i.e. is a signature of the ejection mechanism, or postdates is, which would make it a signature of re-accretion of some of the disk-material. However, the observed evidence leans towards the re-accretion hypothesis. Two further stars showing the effect of variable line width in correlation with emission activity, namely 66 Oph and $\\pi$ Aqr, are presented as well.

  4. Constraints on widths of mixed pentaquark multiplets

    Mohta, V

    2004-01-01

    We determine constraints on the partial widths of mixed pentaquark multiplets in the framework of heavy baryon chiral perturbation theory (HB$\\chi$PT). The partial widths satisfy a GMO-type relation at leading order in HB$\\chi$PT, for arbitrary mixing. The widths of N(1440), N(1710), and $\\Theta(1540)$ are not consistent with ideal mixing, $\\theta_{N} = 35.3^{\\circ}$, but are consistent with $\\theta_{N} \\lesssim 25^{\\circ}$. Furthermore, there are parameter values in HB$\\chi$PT that produce such a mixing angle while allowing the identification of the mass spectrum above. As an alternative to non-ideal mixing, we also suggest reasons for giving up on N(1440) as a pure pentaquark state.

  5. Measured, calculated and estimated stark width values

    The main objective of this study is to compare the recent experimental and theoretical Stark HWHM (half-width at half intensity maximum) results with the values that follow from previously established regularities. This comparison has been done for all Stark widths of spectral lines of ions along the isoelectronic sequence of lithium for 3s 2S-3p 2P0 transition. It has been shown that the Equation (2) can be used for simple, quick and reliable estimation of Stark widths along the lithium isoelectronic sequence for 3s-3p transition. Therefore, Equation (1) is recommended to be applied to the other isoelectronic and iso nuclear sequence for different types of transitions. (author)

  6. Equivalence in radionuclide metrology

    The harmonization of different National Measurement Systems depends on the ability to demonstrate Equivalence between them. The responsibility for establishing a procedure to achieve this lies with the International Committee of Weights and Measures (CIPM) and its associated Consultative Committees. In pursuit of these ends, a series of general recommendations and procedures have been developed by BIPM in order to achieve these objectives. Central to these recommendations is the concept of Key Comparisons which involve a series of comparison exercises both within and between the regional metrology organizations, such as EUROMET, NORAMET and APMP. Because of the unique nature of radioactivity standardization, this generalized procedure is, for practical purposes, impossible to apply in the field of radionuclide metrology. The remedy has been the development of a protocol which optimizes both the current effort available within existing National Metrology Institutes (NMIs) and the considerable amount of data from previous intercomparisons. This paper details this novel approach, provides practical examples, discusses potential problems and examines the way in which the programme will continue and expand

  7. High Fin Width Mosfet Using Gaa Structure

    S.L.Tripathi

    2012-10-01

    Full Text Available This paper describes the design and optimization of gate-all-around (GAA MOSFETs structures. The optimum value of Fin width and Fin height are investigated for superior sub threshold behavior. Also the performance of Fin shaped GAA with gate oxide HfO2 are simulated and compared with conventional gate oxide SiO2 for the same structure. As a result, it was observed that the GAA with high K dielectric gate oxide has more possibility to optimize the Fin width with improved performance. All the simulations are performed on 3-D TCAD device simulator.

  8. High Fin Width Mosfet Using Gaa Structure

    S.L.Tripathi

    2012-11-01

    Full Text Available This paper describes the design and optimization of gate-all-around (GAA MOSFETs structures. The optimum value of Fin width and Fin height are investigated for superior subthreshold behavior. Also the performance of Fin shaped GAA with gate oxide HfO2 are simulated and compared with conventional gate oxide SiO2 for the same structure. As a result, it was observed that the GAA with high K dielectric gate oxide has more possibility to optimize the Fin width with improved performance. All the simulations are performed on 3-D TCAD device simulator.

  9. The Higgs Boson Width is Adjustable

    Chivukula, R. Sekhar; Dugan, Michael J.; Golden, Mitchell

    1994-01-01

    We show that it is possible to construct models in which the width of the Higgs boson is arbitrary - either smaller or larger than a standard model Higgs boson of the same mass. There are no new fields into which the Higgs boson decays. Instead, the coupling of the Higgs boson to the gauge bosons is adjusted. We construct and analyze weakly--coupled models with arbitrary--width Higgs bosons to investigate the phenomenology one might find in a strongly interacting model. In any such model new ...

  10. Effective spectrum width of the synchrotron radiation

    For an exact quantitative description of spectral properties of synchrotron radiation (SR), the concept of effective width of the spectrum is introduced. In the most interesting case, which corresponds to the ultrarelativistic limit of SR, the effective width of the spectrum is calculated for the polarization components, and new physically important quantitative information on the structure of spectral distributions is obtained. For the first time, the spectral distribution for the circular polarization component of the SR for the upper half-space is obtained within classical theory

  11. Beyond Hypertree Width: Decomposition Methods Without Decompositions

    Chen, H; Chen, Hubie; Dalmau, Victor

    2005-01-01

    The general intractability of the constraint satisfaction problem has motivated the study of restrictions on this problem that permit polynomial-time solvability. One major line of work has focused on structural restrictions, which arise from restricting the interaction among constraint scopes. In this paper, we engage in a mathematical investigation of generalized hypertree width, a structural measure that has up to recently eluded study. We obtain a number of computational results, including a simple proof of the tractability of CSP instances having bounded generalized hypertree width.

  12. Measurement of the invisible W width

    The results of the W pair production cross section measurements at the LEP II experiments are used to obtain a measurement of the invisible decay width of the W boson. Such an invisible decay width, resulting from W decay channels that have event signatures that are not consistent with any Standard Model decay, would lower the observed cross section compared to that of the Standard Model. From the LEP combined result from the 183 GeV data gathered in 1997, we obtain an upper limit of 45 MeV at 95% CL. (author)

  13. Effective spectrum width of the synchrotron radiation

    Bagrov, V.G. [Tomsk State University, Department of Physics, Tomsk (Russian Federation); SB RAS, Institute of High Current Electronics, Tomsk (Russian Federation); Gitman, D.M. [Tomsk State University, Department of Physics, Tomsk (Russian Federation); University of Sao Paulo, Institute of Physics, Sao Paulo (Brazil); P.N. Lebedev Physical Institute, Moscow (Russian Federation); Levin, A.D. [University of Sao Paulo, Institute of Physics, Sao Paulo (Brazil); Loginov, A.S.; Saprykin, A.D. [Tomsk State University, Department of Physics, Tomsk (Russian Federation)

    2015-11-15

    For an exact quantitative description of spectral properties of synchrotron radiation (SR), the concept of effective width of the spectrum is introduced. In the most interesting case, which corresponds to the ultrarelativistic limit of SR, the effective width of the spectrum is calculated for the polarization components, and new physically important quantitative information on the structure of spectral distributions is obtained. For the first time, the spectral distribution for the circular polarization component of the SR for the upper half-space is obtained within classical theory. (orig.)

  14. Effective spectrum width of the synchrotron radiation

    Bagrov, V. G., E-mail: bagrov@phys.tsu.ru [Department of Physics, Tomsk State University, Tomsk (Russian Federation); Institute of High Current Electronics, SB RAS, Tomsk (Russian Federation); Gitman, D. M., E-mail: gitman@if.usp.br [Department of Physics, Tomsk State University, Tomsk (Russian Federation); Institute of Physics, University of São Paulo, São Paulo (Brazil); P.N.Lebedev Physical Institute, Moscow (Russian Federation); Levin, A. D., E-mail: alevin@if.usp.br [Institute of Physics, University of São Paulo, São Paulo (Brazil); Loginov, A. S.; Saprykin, A. D. [Department of Physics, Tomsk State University, Tomsk (Russian Federation)

    2015-11-25

    For an exact quantitative description of spectral properties of synchrotron radiation (SR), the concept of effective width of the spectrum is introduced. In the most interesting case, which corresponds to the ultrarelativistic limit of SR, the effective width of the spectrum is calculated for the polarization components, and new physically important quantitative information on the structure of spectral distributions is obtained. For the first time, the spectral distribution for the circular polarization component of the SR for the upper half-space is obtained within classical theory.

  15. ${^3{\\rm He}}(\\alpha,\\gamma){^7{\\rm Be}}$ and ${^3{\\rm H}}(\\alpha,\\gamma){^7{\\rm Li}}$ astrophysical $S$ factors from the no-core shell model with continuum

    Dohet-Eraly, Jérémy; Quaglioni, Sofia; Horiuchi, Wataru; Hupin, Guillaume; Raimondi, Francesco

    2015-01-01

    The ${^3{\\rm He}}(\\alpha,\\gamma){^7{\\rm Be}}$ and ${^3{\\rm H}}(\\alpha,\\gamma){^7{\\rm Li}}$ astrophysical $S$ factors are calculated within the no-core shell model with continuum using a renormalized chiral nucleon-nucleon interaction. The ${^3{\\rm He}}(\\alpha,\\gamma){^7{\\rm Be}}$ astrophysical $S$ factors agree reasonably well with the experimental data while the ${^3{\\rm H}}(\\alpha,\\gamma){^7{\\rm Li}}$ ones are overestimated. The seven-nucleon bound and resonance states and the $\\alpha+{^3{\\rm He}}/{^3{\\rm H}}$ elastic scattering are also studied and compared with experiment. The low-lying resonance properties are rather well reproduced by our approach. At low energies, the $s$-wave phase shift, which is non-resonant, is overestimated.

  16. The equivalence principle

    The prerelativistic history of the equivalence principle (EP) is presented briefly. Its role in history of the general relativity theory (G.R.T.) discovery is elucidated. A modern idea states that the ratio of inert and gravitational masses does not differ from 1 at least up to the 12 sign after comma. Attention is paid to the difference of the gravitational field from electromagnetic one. The difference is as follows, the energy of the gravitational field distributed in space is the source of the field. These fields always interact at superposition. Electromagnetic fields from different sources are put together. On the basis of EP it is established the Sun field interact with the Earth gravitational energy in the same way as with any other one. The latter proves the existence of gravitation of the very gravitational field to a heavy body. A problem on gyroscope movement in the Earth gravitational field is presented as a paradox. The calculation has shown that gyroscope at satellite makes a positive precession, and its axis turns in an angle equal to ? during a turn of the satellite round the Earth, but because of the space curvature - into the angle two times larger than ?. A resulting turn is equal to 3?. It is shown on the EP basis that the polarization plane in any coordinate system does not turn when the ray of light passes in the gravitational field. Together with the historical value of EP noted is the necessity to take into account the requirements claimed by the EP at description of the physical world

  17. Definition of the ? mass and width

    In the framework of effective field theory we show that, at two-loop order, the mass and width of the ? resonance defined via the (relativistic) Breit-Wigner parametrization both depend on the choice of field variables. In contrast, the complex-valued position of the pole of the propagator is independent of this choice

  18. Bounding the Higgs boson width through interferometry.

    Dixon, Lance J; Li, Ye

    2013-09-13

    We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg???. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum. PMID:24074073

  19. Certainty Equivalent in Capital Markets

    Kruschwitz, Lutz; Löffler, Andreas

    2003-01-01

    We generalize the classical concept of a certainty equivalent to a model where an investor can trade on a capital market with several future trading dates. We show that if a riskless asset is traded and the investor has a CARA utility then our generalized certainty equivalent can be evaluated using the sum of discounted one-period certainty equivalents. This is not true if the investor has a HARA utility.

  20. Flow equivalence of sofic shifts

    Boyle, Mike; Carlsen, Toke Meier; Eilers, Søren

    2015-01-01

    We classify certain sofic shifts (the irreducible Point Extension Type, or PET, sofic shifts) up to flow equivalence, using invariants of the canonical Fischer cover. There are two main ingredients: (1) An extension theorem, for extending flow equivalences of subshifts to flow equivalent irreducible shifts of finite type which contain them. (2) The classification of certain constant to one maps from SFTs via algebraic invariants of associated G-SFTs.

  1. Testing statistical hypotheses of equivalence

    Wellek, Stefan

    2010-01-01

    Equivalence testing has grown significantly in importance over the last two decades, especially as its relevance to a variety of applications has become understood. Yet published work on the general methodology remains scattered in specialists' journals, and for the most part, it focuses on the relatively narrow topic of bioequivalence assessment.With a far broader perspective, Testing Statistical Hypotheses of Equivalence provides the first comprehensive treatment of statistical equivalence testing. The author addresses a spectrum of specific, two-sided equivalence testing problems, from the

  2. Estimating equivalence with quantile regression

    Cade, B.S.

    2011-01-01

    Equivalence testing and corresponding confidence interval estimates are used to provide more enlightened statistical statements about parameter estimates by relating them to intervals of effect sizes deemed to be of scientific or practical importance rather than just to an effect size of zero. Equivalence tests and confidence interval estimates are based on a null hypothesis that a parameter estimate is either outside (inequivalence hypothesis) or inside (equivalence hypothesis) an equivalence region, depending on the question of interest and assignment of risk. The former approach, often referred to as bioequivalence testing, is often used in regulatory settings because it reverses the burden of proof compared to a standard test of significance, following a precautionary principle for environmental protection. Unfortunately, many applications of equivalence testing focus on establishing average equivalence by estimating differences in means of distributions that do not have homogeneous variances. I discuss how to compare equivalence across quantiles of distributions using confidence intervals on quantile regression estimates that detect differences in heterogeneous distributions missed by focusing on means. I used one-tailed confidence intervals based on inequivalence hypotheses in a two-group treatment-control design for estimating bioequivalence of arsenic concentrations in soils at an old ammunition testing site and bioequivalence of vegetation biomass at a reclaimed mining site. Two-tailed confidence intervals based both on inequivalence and equivalence hypotheses were used to examine quantile equivalence for negligible trends over time for a continuous exponential model of amphibian abundance. ?? 2011 by the Ecological Society of America.

  3. Derived Equivalence in Surface Algebras via Graded Equivalence

    David-Roesler, Lucas

    2011-01-01

    We determine some of the derived equivalences of a class of gentle algebras called surface algebras. These algebras are constructed from an unpunctured Riemann surface with boundary and marked points by introducing cuts in internal triangles of an arbitrary triangulation of the surface. In particular, we fix a triangulation of a surface and determine when different cuts produce derived equivalent algebras.

  4. Accurate valence band width of diamond

    An accurate width is determined for the valence band of diamond by imaging photoelectron momentum distributions for a variety of initial- and final-state energies. The experimental result of 23.0±0.2 eV2 agrees well with first-principles quasiparticle calculations (23.0 and 22.88 eV) and significantly exceeds the local-density-functional width, 21.5±0.2 eV2. This difference quantifies effects of creating an excited hole state (with associated many-body effects) in a band measurement vs studying ground-state properties treated by local-density-functional calculations. copyright 1997 The American Physical Society

  5. LEP hadronic Z0 partial widths

    The experimental situation on hadronic Z0 partial widths at LEP is reviewed. In the absence of recent results on light quarks, only new data concerning Z0 → b b bar and Z0 → cc bar are considered. A LEP average value of Rb (with a 1% precision) implying low top quark mass or new phenomena within the Standard Model framework is presented. A slight deviation of Rb from the Standard Model value is observed. 6 figs., 18 refs

  6. Are There Any Good Digraph Width Measures?

    Ganian, Robert; Hliněný, Petr; Kneis, Joachim; Meister, Daniel; Obdržálek, Jan; Rossmanith, Peter; Sikdar, Somnath

    Several width measures for digraphs have been proposed in the last few years. However, none of them possess all the "nice" properties of treewidth, namely, (1) being algorithmically useful, that is, admitting polynomial-time algorithms for a large class of problems on digraphs of bounded width; and (2) having nice structural properties such as being monotone under taking subdigraphs and some form of arc contractions. As for (1), MSO1 is the least common denominator of all reasonably expressive logical languages that can speak about the edge/arc relation on the vertex set, and so it is quite natural to demand efficient solvability of all MSO1-definable problems in this context. (2) is a necessary condition for a width measure to be characterizable by some version of the cops-and-robber game characterizing treewidth. More specifically, we introduce a notion of a directed topological minor and argue that it is the weakest useful notion of minors for digraphs in this context. Our main result states that any reasonable digraph measure that is algorithmically useful and structurally nice cannot be substantially different from the treewidth of the underlying undirected graph.

  7. Equivalences for noncommutative projective spaces

    Vitoria, Jorge

    2010-01-01

    Following Artin and Zhang's formulation of noncommutative projective geometry, we classify up a family of skew polynomial quadratic algebras up to graded Morita equivalence and their corresponding noncommutative projective spaces up to birational equivalences. We also study their point varieties and provide examples of non-isomorphic noncommutative projective spaces.

  8. Convolution equivalence and infinite divisibility

    Pakes, Anthony G.

    2004-01-01

    Known results relating the tail behaviour of a compound Poisson distribution function to that of its Lévy measure when one of them is convolution equivalent are extended to general infinitely divisible distributions. A tail equivalence result is obtained for random sum distributions in which the summands have a two-sided distribution.

  9. Matching of equivalent field regions

    Appel-Hansen, Jørgen; Rengarajan, S.B.

    2005-01-01

    In aperture problems, integral equations for equivalent currents are often found by enforcing matching of equivalent fields. The enforcement is made in the aperture surface region adjoining the two volumes on each side of the aperture. In the case of an aperture in a planar perfectly conducting s...

  10. Morita Equivalence of Noncommutative Supertori

    Chang-Young, Ee; Nakajima, Hiroaki

    2009-01-01

    In this paper we study an extension of the Morita equivalence of noncommutative tori to the supersymmetric case. We restrict our investigation mainly to the two dimensional case in which noncommutative supertori have been constructed recently. Our main focus is to know how the supersymmetry affect the symmetry relations giving the Morita equivalence in the bosonic noncommutative tori case. It turns out that the structure of the symmetry group acting on the noncommutativity parameters yielding the Morita equivalence remains intact but its field become supersymmetric having both body and soul parts. The extension of the Morita equivalence to the higher dimensional case could not be carried out due to lack of complete understanding of the classification and construction of all possible higher dimensional noncommutative supertori. However, even in the higher dimensional case there seems to be a certain indication that the structure of the symmetry group yielding Morita equivalence remains unchanged from the boson...

  11. Unitary equivalence of quantum walks

    Highlights: • We have found unitary equivalent classes in coined quantum walks. • A single parameter family of coin operators is sufficient to realize all simple one-dimensional quantum walks. • Electric quantum walks are unitarily equivalent to time dependent quantum walks. - Abstract: A simple coined quantum walk in one dimension can be characterized by a SU(2) operator with three parameters which represents the coin toss. However, different such coin toss operators lead to equivalent dynamics of the quantum walker. In this manuscript we present the unitary equivalence classes of quantum walks and show that all the nonequivalent quantum walks can be distinguished by a single parameter. Moreover, we argue that the electric quantum walks are equivalent to quantum walks with time dependent coin toss operator

  12. Concurrent Supermassive Black Hole and Galazy Growth: Linking Environment and Nuclear Activity in Zeta Equals 2.23 H Alpha Emitters

    Lehmer, B. D.; Lucy, A. B.; Alexander, D. M.; Best, P. N.; Geach, J. E.; Harrison, C. M.; Hornschemeier, A. E.; Matsuda, Y.; Mullaney, J. R.; Smail, Ian; Sobral, D.; Swinbank, A. M.

    2013-01-01

    We present results from an approximately equal 100 ks Chandra observation of the 2QZ Cluster 1004+00 structure at z = 2.23 (hereafter 2QZ Clus). 2QZ Clus was originally identified as an overdensity of four optically-selected QSOs at z = 2.23 within a 15 × 15 arcmin square region. Narrow-band imaging in the near-IR (within the K band) revealed that the structure contains an additional overdensity of 22 z = 2.23 H alpha-emitting galaxies (HAEs), resulting in 23 unique z = 2.23 HAEs/QSOs (22 within the Chandra field of view). Our Chandra observations reveal that three HAEs in addition to the four QSOs harbor powerfully accreting supermassive black holes (SMBHs), with 2-10 keV luminosities of approximately equal (8-60) × 10(exp 43) erg s(exp-1) and X-ray spectral slopes consistent with unobscured active galactic nucleus (AGN). Using a large comparison sample of 210 z = 2.23 HAEs in the Chandra-COSMOS field (C-COSMOS), we find suggestive evidence that the AGN fraction increases with local HAE galaxy density. The 2QZ Clus HAEs reside in a moderately overdense environment (a factor of approximately equal 2 times over the field), and after excluding optically-selected QSOs, we find that the AGN fraction is a factor of approximately equal 3.5(+3.8/ -2.2) times higher than C-COSMOS HAEs in similar environments. Using stacking analyses of the Chandra data and Herschel SPIRE observations at 250micrometers, we respectively estimate mean SMBH accretion rates ( M(BH)) and star formation rates (SFRs) for the 2QZ Clus and C-COSMOS samples. We find that the mean 2QZ Clus HAE stacked X-ray luminosity is QSO-like (L(2-10 keV) approximately equal [6-10] × 10(exp 43) erg s(exp -1)), and the implied M(BH)/SFR approximately equal (1.6-3.2) × 10(exp -3) is broadly consistent with the local M(BH)/Stellar Mass relation and z approximately equal 2 X-ray selected AGN. In contrast, the C-COSMOS HAEs are on average an order of magnitude less X-ray luminous and have M(BH)/SFR approximately equal (0.2-0.4) × 10(exp -3), somewhat lower than the local MBH/M relation, but comparable to that found for z approximately equal 1-2 star-forming galaxies with similar mean X-ray luminosities. We estimate that a periodic QSO phase with duty cycle approximately 2%-8% would be sufficient to bring star-forming galaxies onto the local M(BH)/Stellar Mass relation. This duty cycle is broadly consistent with the observed C-COSMOS HAE AGN fraction (Approximately equal 0.4%-2.3%) for powerful AGN with LX approximately greater than 10(exp 44) erg s(exp -1). Future observations of 2QZ Clus will be needed to identify key factors responsible for driving the mutual growth of the SMBHs and galaxies.

  13. Morita equivalence of noncommutative supertori

    In this paper we study the extension of Morita equivalence of noncommutative tori to the supersymmetric case. The structure of the symmetry group yielding Morita equivalence appears to be intact but its parameter field becomes supersymmetrized having both body and soul parts. Our result is mainly in the two dimensional case in which noncommutative supertori have been constructed recently: The group SO(2,2,VZ0), where VZ0 denotes Grassmann even number whose body part belongs to Z, yields Morita equivalent noncommutative supertori in two dimensions.

  14. Nuclear structure effects on α reduced widths

    A review of α widths for s-wave transitions is presented together with a discussion of the following topics: 1) a new determination of the /sup 218/Ra half-life and its relation to reflection asymmetry in nuclei near N = 130, 2) a measurement of the /sup 194/Pb α-decay rate and the influence of the Z = 82 gap on neutron-deficient Pb nuclei and 3) an up-date of α-decay-rate systematics for isotopes in the rare earth and medium-weight mass regions

  15. ICD-10 Master Equivalence Map

    U.S. Department of Health & Human Services — DISCLAIMER: The Master Equivalence Map includes all existing ICD-9 and ICD-10 codes. It is not intended to be used as an ICD-10 conversion or crosswalk tool. The...

  16. Pulse width modulation inverter with battery charger

    Slicker, James M. (Union Lake, MI)

    1985-01-01

    An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a "flyback" DC-DC converter circuit for recharging the battery.

  17. Pulse width modulation inverter with battery charger

    Slicker, James M. (Inventor)

    1985-01-01

    An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a flyback DC-DC converter circuit for recharging the battery.

  18. Pion Decay Widths of D mesons

    Henriksson, K O E; Nyflt, C J; Riska, D O

    2001-01-01

    The pionic decay rates of the excited $L=0,1$ $D$ mesons are calculated with a Hamiltonian model within the framework of the covariant Blankenbecler-Sugar {equation.} The interaction between the light quark and charm antiquark is described by a linear scalar confining and a screened one-gluon exchange interaction. The decay widths of the $D^*$ mesons obtain a contribution from the exchange current that is associated with the linear scalar confining interaction. If this contribution is taken into account along with the single quark approximation, the calculated decay rates of the charged $D^*$ mesons are readily below the current empirical upper limits if the axial coupling constant of the light constituent quarks is taken to be $g_A^q$ = 0.87, but reach the empirical upper limits if $g_A^q$ = 1. With the conventional values for $g_A^q$, the calculated widths of the $D_1$ and $D_2^*$ mesons fall somewhat below the experimental lower limits, leaving room for other decay modes as well, such as $\\pi\\pi$ decay. Th...

  19. Equivalence Principle and Gravitational Redshift

    Hohensee, Michael A; Peters, Achim; Mueller, Holger

    2011-01-01

    We investigate leading order deviations from general relativity that violate the Einstein equivalence principle (EEP) in the gravitational standard model extension (SME). We show that redshift experiments based on matter waves and clock comparisons are equivalent to one another. Consideration of torsion balance tests, along with matter wave, microwave, optical, and M\\"ossbauer clock tests yields comprehensive limits on spin-independent EEP-violating SME terms at the $10^{-6}$ level.

  20. Egalitarian Equivalence under Asymmetric Information

    Geoffroy de Clippel; David Pérez-Castrillo and David Wettstein

    2015-01-01

    We propose a definition of egalitarian equivalence that extends Pazner and Schmeidler's (1978) concept to environments with incomplete information. If every feasible allocation rule can be implemented by an incentive compatible mechanism (as, for instance, in the case of non-exclusive information), then interim egalitarian equivalence and interim incentive efficiency remain compatible, as they were under complete information. When incentive constraints are more restrictive, on the other hand,...

  1. Egalitarian equivalence under asymmetric information

    DE CLIPPEL, Geoffroy; Pérez-Castrillo, David; WETTSTEIN, David

    2010-01-01

    We propose a definition of egalitarian equivalence that extends Pazner and Schmeidler's (1978) concept to environments with incomplete information. If every feasible allocation rule can be implemented by an incentive compatible mechanism (as, for instance, in the case of non-exclusive information), then interim egalitarian equivalence and interim incentive efficiency remain compatible, as they were under complete information. When incentive constraints are more restrictive, on the other hand,...

  2. Acquired Equivalence Changes Stimulus Representations

    Meeter, M; Shohamy, D; Myers, C.E.

    2009-01-01

    Acquired equivalence is a paradigm in which generalization is increased between two superficially dissimilar stimuli (or antecedents) that have previously been associated with similar outcomes (or consequents). Several possible mechanisms have been proposed, including changes in stimulus representations, either in the form of added associations or a change of feature salience. A different way of conceptualizing acquired equivalence is in terms of strategic inference: Confronted with a choice ...

  3. Analytic equivalence of geometric transitions

    Rossi, Michele

    2008-01-01

    In this paper \\emph{analytic equivalence} of geometric transition is defined in such a way that equivalence classes of geometric transitions turn out to be the \\emph{arrows} of the \\cy web. Then it seems natural and useful, both from the mathematical and physical point of view, look for privileged arrows' representatives, called \\emph{canonical models}, laying the foundations of an \\emph{analytic} classification of geometric transitions. At this purpose a numerical invariant, called \\emph{bi-...

  4. Approximation of reduced width amplitude and application to cluster decay width

    Kanada-En'yo, Yoshiko; Taniguchi, Yasutaka

    2014-01-01

    We propose a simple method to approximately evaluate reduced width amplitude (RWA) of a two-body spinless cluster channel using the norm overlap with the Brink-Bloch cluster wave function at the channel radius. The applicability of the present approximation is tested for the $^{16}$O+$\\alpha$ channel in $^{20}$Ne as well as the $\\alpha$+$\\alpha$ channel in $^8$Be. The approximation is found to be reasonable to evaluate the RWA for states near the threshold energy and it is useful to estimate the $\\alpha$-decay width of resonance states. The approximation is also applied to $^9$Li, and the partial decay width of the $^6$He($0^+_1$)+$t$ channel is discussed.

  5. Transient radiation effects of CMOS circuits with different pulse widths

    Transient radiation response on CMOS circuits were investigated for different pulse widths. CMOS circuits 4007, 4069 and 6264 were irradiated using 'Qiangguang-I' accelerator source. Latchup thresholds of CMOS inverters and upset level of CMOS SRAM with different pulse widths were obtained. The data clearly indicate dose-rate dependency on the pulse widths. The latchup threshold for 4007 and 4069 at 20 ns pulse width is 2 times that at 150 ns. The upset level for 6264 at 20 ns pulse width is 3 times that at 150 ns. The results show that the damage thresholds decrease with the increase of pulse widths. (authors)

  6. Direct measurement of the W boson width

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

    2009-09-01

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W {yields} e{nu} candidates selected in 1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider in p{bar p} collisions at {radical}s = 1.96 TeV. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 {+-} 0.072 GeV, is in agreement with the predictions of the standard model and is the most precise direct measurement result from a single experiment to date.

  7. Measurement of radiative widths at COMPASS

    COMPASS is a multi-purpose fixed-target experiment at CERN SPS, that investigates the structure and spectroscopy of hadrons. Dissociation of pions on nuclear or hydrogen targets provides clean access to the light meson spectrum. During a short run with π- beam on lead in the year 2004, about 4 million exclusive π-π-π+ events have been collected. For the 3 million events with low momentum transfer t' 2/c2, coherent scattering off the nucleus as a whole can be assumed, with contributions from Reggeon (Pomeron) and quasi-real photon exchange. For the lowest t' 2/c2, the electromagnetic interaction part becomes apparent. The partial-wave analysis of these data leads to the observation of resonances as the a2(1320) dominantly produced by quasi-real photon exchange. The extraction of their radiative widths is presented.

  8. Joint H-alpha and X-ray Observations of Massive X-ray Binaries. I. The B-Supergiant System LS I +65 010 = 2S 0114+650

    Grundstrom, E D; Gies, D R; Huang, W; McSwain, M V; Raghavan, D; Riddle, R L; Subasavage, J P; Wingert, D W; Levine, A M; Remillard, R A

    2006-01-01

    We report on a three year spectroscopic monitoring program of the H-alpha emission in the massive X-ray binary LS I +65 010 = 2S 0114+650, which consists of a B-supergiant and a slowly rotating X-ray pulsar. We present revised orbital elements that yield a period of P=11.5983 +/- 0.0006 d and confirm that the orbit has a non-zero eccentricity e=0.18 +/- 0.05. The H-alpha emission profile is formed in the base of the wind of the B-supergiant primary, and we show how this spectral feature varies on timescales that are probably related to the rotational period of the B-supergiant. We also examine the X-ray fluxes from the Rossi X-ray Timing Explorer All-Sky Monitor instrument, and we show that the X-ray orbital light curve has a maximum at periastron and a minimum at the inferior conjunction of the B-supergiant. We also show that the wind emission strength and the high energy X-ray flux appear to vary in tandem on timescales of approximately a year.

  9. Equivalent linearization of impacting structures

    Complex industrial structures are generally divided in several substructures. Even if the global behavior of the structure may by considered as linear, some substructures present local nonlinearities like impacts, sliding, or plasticity. To study the response of the whole structure the usual method consists of replacing the nonlinear substructures by linear models. The effect of the substructure is made equivalent to the nonlinear effect of the real substructure. Such equivalent models are called Linear Equivalent Models (LEM). This paper is mainly focused on the seismic behaviour of structures impacting on supports with gaps (for example pipes, steam generator etc...). Classical approaches to determine LEM consist generally in replacing the nonlinear support by a spring which stiffness is a function of the gap value and the excitation level. The limitations of such method will be identified in the case of a 1 degree of freedom (DOF) nonlinear oscillator. A new principle of LEM will be proposed and applied to this lDOF structure

  10. Equivalence principle for scalar forces.

    Hui, Lam; Nicolis, Alberto

    2010-12-01

    The equivalence of inertial and gravitational masses is a defining feature of general relativity. Here, we clarify the status of the equivalence principle for interactions mediated by a universally coupled scalar, motivated partly by recent attempts to modify gravity at cosmological distances. Although a universal scalar-matter coupling is not mandatory, once postulated, it is stable against classical and quantum renormalizations in the matter sector. The coupling strength itself is subject to renormalization, of course. The scalar equivalence principle is violated only for objects for which either the graviton self-interaction or the scalar self-interaction is important--the first applies to black holes, while the second type of violation is avoided if the scalar is Galilean symmetric. PMID:21231444

  11. Frequency dependence of pulse width for 150 radio normal pulsars

    Chen, J L

    2014-01-01

    The frequency dependence of pulse width is studied for 150 normal pulsars, mostly selected from the European Pulsar Network, of which the multi-frequency 10% pulse widths can be well fitted with the Thorsett relationship $W_{10}=A\

  12. Lake Basin Fetch and Maximum Length/Width

    Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake...

  13. Sievert, gray and dose equivalent.

    Pfalzner, P M

    1983-12-01

    The concepts of physical quantity and physical units of measurement are presented. The relations between quantities, the names and symbols for SI (International System) base units, derived units and special names of SI units are illustrated. From the definition of the radiation quantity dose equivalent, the SI unit for this quantity is shown to be dimensionally identical with the joule per kilogram. The sievert (Sv) is the special (restricted) name for the SI unit of the quantity dose equivalent, with 1 Sv = 1 J/kg. PMID:6668293

  14. Anomalous equivalence of cosmological frames

    Herrero-Valea, Mario

    2016-01-01

    We study the question of whether two frames of a given physical theory are equivalent or not in the presence of quantum corrections. By using field theory arguments we claim that equivalence is broken in the presence of anomalous symmetries in one of the frames. This is particularized to the case of the relation between the Einstein and Jordan frames in scalar-tensor theories used to describe early Universe dynamics. Although a regularization that solves the tension exists, it requires the introduction of non-polynomial counterterms that can spoil other useful properties.

  15. Affine varieties with equivalent cylinders

    Yu, JT; Shpilrain, V

    2001-01-01

    A well-known cancellation problem asks when, for two algebraic varieties $V_1, V_2 \\subseteq {\\bf C}^n$, the isomorphism of the cylinders $V_1 \\times {\\bf C}$ and $V_2 \\times {\\bf C}$ implies the isomorphism of $V_1$ and $V_2$. In this paper, we address a related problem: when the equivalence (under an automorphism of ${\\bf C}^{n+1}$) of two cylinders $V_1 \\times {\\bf C}$ and $V_2 \\times {\\bf C}$ implies the equivalence of their bases $V_1$ and $V_2$ under an automorphism of ${\\bf C}^n$? We c...

  16. Detection of Broad H$\\alpha$ Emission Lines in the Late-time Spectra of a Hydrogen-poor Superluminous Supernova

    Yan, Lin; Ofek, E; Gal-Yam, A; Mazzali, P; Perley, D; Vreeswijk, P; Leloudas, G; de Cia, A; Masci, F; Cenko, S B; Cao, Y; Kulkarni, S R; Nugent, P E; Rebbapragada, Umaa D; Wo?niak, P R; Yaron, O

    2015-01-01

    iPTF13ehe is a hydrogen-poor superluminous supernova (SLSN) at z=0.3434, with properties similar to SN2007bi. It rises within (83-148)days (rest-frame) to reach a peak bolometric luminosity of 1.3x$10^{44}$erg/s, then decays very slowly at 0.015mag. per day. The measured ejecta velocity is 13000km/s. The inferred explosion characteristics, such as the ejecta mass (67-220$M_\\odot$), the total radiative and kinetic energy ($10^{51}$ & 2x$10^{53}$erg respectively), is typical of SLSN-R events. However, the late-time spectrum taken at +251days reveals a Balmer Halpha emission feature with broad and narrow components, which has never been detected before among other H-poor SLSNe. The broad component has a velocity width of ~4500km/s and has a ~300km/s blue-ward shift relative to the narrow component. We interpret this broad Halpha emission line as the interaction between the supernova ejecta and a H-rich circumstellar medium (CSM) shell, located at a distance of ~4x$10^{16}$cm from the explosion site. This eje...

  17. Influence of γ irradiation on band width of optical fibers

    The effect of band width of the multimode step index fibers under γ irradiation has been investigated. It was found that band width of the optical fibers decreased as irradiation dose increased, and the decrease of band width reached to 60%. The possible cause for the result is discussed

  18. Poisson geometry and Morita equivalence

    Bursztyn, Henrique; Weinstein, Alan

    2004-01-01

    These notes discuss various aspect of the ``representation theory'' of Poisson manifolds, with focus on Morita equivalence and Picard groups. We give a brief introduction to Poisson geometry (including Dirac and twisted Poisson structures) and algebraic Morita theory before presenting the geometric Morita theory of Poisson manifolds. We also point out the connections with the theory of symplectic groupoids and hamiltonian actions.

  19. Equivalence principle in classical electrodynamics

    Bozhidar Z. Iliev

    2003-01-01

    The principle of equivalence in gravitational physics and its mathematical base are reviewed. It is demonstrated how this principle can be realized in classical electrodynamis. In general, it is valid at any given single point or along a path without selfintersections unless the field considered satisfies some conditions.

  20. Comments on field equivalence principles

    Appel-Hansen, Jørgen

    1987-01-01

    It is pointed Out that often-used arguments based on a short-circuit concept in presentations of field equivalence principles are not correct. An alternative presentation based on the uniqueness theorem is given. It does not contradict the results obtained by using the short-circuit concept but...

  1. Morita "equivalences" of equivariant torus spectral triples

    Venselaar, Jan Jitse

    2011-01-01

    In general, Morita equivalence of spectral triples need not be a symmetric relation. In this paper, we show that Morita equivalence of spectral triples is an equivalence relation for equivariant torus spectral triples.

  2. On graph classes with logarithmic boolean-width

    Belmonte, Rmy; Vatshelle, Martin

    2010-01-01

    Boolean-width is a recently introduced graph parameter. Many problems are fixed parameter tractable when parametrized by boolean-width, for instance "Minimum Weighted Dominating Set" (MWDS) problem can be solved in $O^*(2^{3k})$ time given a boolean-decomposition of width $k$, hence for all graph classes where a boolean-decomposition of width $O(\\log n)$ can be found in polynomial time, MWDS can be solved in polynomial time. We study graph classes having boolean-width $O(\\log n)$ and problems...

  3. Global synchronization of parallel processors using clock pulse width modulation

    Chen, Dong; Ellavsky, Matthew R.; Franke, Ross L.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Jeanson, Mark J.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Littrell, Daniel; Ohmacht, Martin; Reed, Don D.; Schenck, Brandon E.; Swetz, Richard A.

    2013-04-02

    A circuit generates a global clock signal with a pulse width modification to synchronize processors in a parallel computing system. The circuit may include a hardware module and a clock splitter. The hardware module may generate a clock signal and performs a pulse width modification on the clock signal. The pulse width modification changes a pulse width within a clock period in the clock signal. The clock splitter may distribute the pulse width modified clock signal to a plurality of processors in the parallel computing system.

  4. Equivalence of conservation laws and equivalence of potential systems

    Ivanova, Nataliya M.; Popovych, Roman O.

    2006-01-01

    We study conservation laws and potential symmetries of (systems of) differential equations applying equivalence relations generated by point transformations between the equations. A Fokker-Planck equation and the Burgers equation are considered as examples. Using reducibility of them to the one-dimensional linear heat equation, we construct complete hierarchies of local and potential conservation laws for them and describe, in some sense, all their potential symmetries. Known results on the s...

  5. GAP WIDTH STUDY IN LASER BUTT-WELDING

    Gong, Hui; Olsen, Flemming Ove

    In this paper the maximum allowable gap width in laser butt-welding is intensively studied. The gap width study (GWS) is performed on the material of SST of W1.4401 (AISI 316) under various welding conditions, which are the gap width : 0.00-0.50 mm, the welding speed : 0.5-2.0 m/min, the laser...... power : 2 and 2.6 kW and the focal point position : 0 and -1.2 mm. Quality of all the butt welds are destructively tested according to ISO 13919-1.Influences of the variable process parameters to the maximum allowable gap width are observed as (1) the maximum gap width is inversely related to the...... welding speed, (2) the larger laser power leads to the bigger maximum allowable gap width and (3) the focal point position has very little influence on the maximum gap width....

  6. ?onsolidation and creepof subfoundations having finite widths ???????????? ? ?????????? ????????? ??????????? ???????? ??????

    Ter-Martirosyan Zaven Grigorevich

    2013-04-01

    Full Text Available The authors formulate and solve the problem of consolidation and creep of saturated clay subfoundations exposed to localized loads (the two-dimensional problem formulation. The findings have proven that, if the two-dimensional problem is considered, any excessive pore pressure is concentrated immediately under the area exposed to the localized loading, and it penetrates into the depth equal to 1/2 of the strength of the compressed width. Subfoundation subsidence is caused by both shear and 3D deformations of soil. Besides, the ratio of shear-to-3D deformations reaches 10. Therefore, the authors propose to represent the subfoundation subsidence as the sum of shear and 3D deformations.The differential equation of the filter consolidation, if considered as the 2D problem, is solved using the Mathcad software. The software is used to analyze the isolines of excessive pore pressure at any moment following the loading application. New depen- dence representing the ratio of the changing area of the diagram of the average effective tension to the area of the diagram of the average tension in the stabilized condition is proposed by the authors.In the final section of the article, the authors solve the problem of prognostication of the subsidence pattern for the water saturated subfoundation with account for the shear creep of the soil skeleton. The authors employ the visco-elastic Bingham model characterized by time-dependent viscosity ratios. The authors have proven that in this case the subsidence following the shear load will develop as of the moment of application of the external load pro rata the logarithm of time irrespectively of the process of filtration consolidation.????????? ?????????? ? ??????? ????? ???????????? ? ?????????? ?????????????? ????????? ?? ????????? ??????? ??? ???????????? ??????? ???????? (??????? ??????. ????????, ??? ? ???????? ??????? ?????? ?????????? ??????? ???????? ? ????????? ?????? ?????????? ???????????? ??????????????? ??? ??????? ????????? ?? ??????? 1/2 ?? ???????? ????????? ????? ? ????? ????????? ???? ?? ??????? ? ??? ?????? ????????? ??????????? ??? ??????????, ??? ? ????????? ???????????? ??????. ????? ????, ??????????? ????????? ? ???????? ?????? ????????? 10. ??????? ?????????? ?????? ????????? ?????????? ? ???? ????? ?? ???????? ? ????????? ?????????? ? ???????????.??? ??????? ????????????????? ????????? ?????????????? ???????????? ? ???????? ?????????? ?????? ???????????? ??????????? ???????? Mathcad. ??? ????????? ??????????? ??????? ?? ??????????? ???????? ??????????? ???????? ???????? ??? ?????? ??????? ??????? ?? ?????? ?????????? ????????. ??? ??????????? ??????? ???????????? ?????? ?????????? ????? ??????????? ? ???? ????????? ???????????? ??????? ????? ???????? ???????????? ?????????? ? ??????? ????? ???????? ?????????? ? ????????????????? ?????????.? ?????????????? ??????? ?????? ????????? ??????? ?????? ?? ??????????????? ?????? ??????????????? ????????? ? ?????? ?????????

  7. VizieR Online Data Catalog: CaII triplet equivalent widths in 30 globulars (Mauro+, 2014)

    Mauro, F.; Moni Bidin, C.; Geisler, D.; Saviane, I.; da Costa, G. S.; Gormaz-Matamala, A. C.; Vasquez, S.; Chene, A.-N.; Cohen, R.; Dias, B.

    2014-03-01

    Our main target list consists of the GCs analyzed by S12 (Saviane et al., 2012, Cat. J/A+A/540/A27). The NIR imaging collected in the context of the VVV Survey was used for all clusters included in the survey area. We also checked whether any of the GCs in the dataset not observed by the VVV Survey had useful 2MASS photometry, that would permit us to determine the RHB position. We similarly selected GCs from the R97 (Rutledge et al., 1997PASP..109..907R) catalog to determine a calibration for this dataset as well (2 data files).

  8. Equivalent Imperfections In Arched Structures

    Dallemule Marian

    2015-09-01

    Full Text Available There are currently three design methods to verify the in-plane buckling of an arched structure: substitute member method, the method of equivalent imperfection with recommendations for arched bridges, and the equivalent unique global and local initial imperfection method (EUGLI, which uses the critical elastic buckling mode as an imperfection. The latter method is included in the EN 1993-1-1 cl. 5.3.2 (11 since 2002; however, to this day it is neither utilized in the design practice nor is it incorporated in ordinary structural analysis software. The main purpose of this article is to show the application of the proposed methods in a step-by-step manner to the numerical example considered and to compare these design methods for various arched structures. Verification of the in-plane buckling of an arch is explained in detail.

  9. Equivalent Imperfections In Arched Structures

    Dallemule, Marian

    2015-09-01

    There are currently three design methods to verify the in-plane buckling of an arched structure: substitute member method, the method of equivalent imperfection with recommendations for arched bridges, and the equivalent unique global and local initial imperfection method (EUGLI), which uses the critical elastic buckling mode as an imperfection. The latter method is included in the EN 1993-1-1 cl. 5.3.2 (11) since 2002; however, to this day it is neither utilized in the design practice nor is it incorporated in ordinary structural analysis software. The main purpose of this article is to show the application of the proposed methods in a step-by-step manner to the numerical example considered and to compare these design methods for various arched structures. Verification of the in-plane buckling of an arch is explained in detail.

  10. Equivalence Principle in Chameleon Models

    Kraiselburd, Lucila; Landau, Susana. J.; Salgado, Marcelo; Sudarsky, Daniel

    2013-01-01

    Most theories that predict time and/or space variation of fundamental constants also predict violations of the Weak Equivalence Principle (WEP). Khoury and Weltmann proposed the chameleon model in 2004 and claimed that this model avoids experimental bounds on WEP. We present a contrasting view based on an approximate calculation of the two body problem for the chameleon field and show that the force depends on the test body composition. Furthermore, we compare the prediction of the force on a...

  11. Equivalence testing in protein binding

    Shi, Xiaofeng

    2007-01-01

    Various routes are used to administer drugs but in most cases drugs reach their site of action via the systemic circulation. After a drug is absorbed into the bloodstream, it rapidly circulates through the body. A drug in blood exists only in two forms as mentioned above, which are bound and unbound. The unbound part generally exhibits pharmacologic effects. The main objective of this study is to find out whether males and females have equivalent values for protein binding. And...

  12. Equivalent circuit analysis of sled

    A direct application of equivalent circuit concepts leads to: (1) confirmation of Perry Wilson's SLED (SLAC Linac Energy Doubler) equation; (2) an equation that applies to a SLED device with input and output waveguides of different characteristic impedances; and (3) an equation that results if we demand that no power be lost by reflection from SLED. If the incident voltage is tailored as prescribed by this equation, the cavity voltage tracks the incident voltage and the reflected voltage is zero

  13. The Stanford equivalence principle program

    Worden, Paul W., Jr.; Everitt, C. W. Francis; Bye, M.

    1989-01-01

    The Stanford Equivalence Principle Program (Worden, Jr. 1983) is intended to test the uniqueness of free fall to the ultimate possible accuracy. The program is being conducted in two phases: first, a ground-based version of the experiment, which should have a sensitivity to differences in rate of fall of one part in 10(exp 12); followed by an orbital experiment with a sensitivity of one part in 10(exp 17) or better. The ground-based experiment, although a sensitive equivalence principle test in its own right, is being used for technology development for the orbital experiment. A secondary goal of the experiment is a search for exotic forces. The instrument is very well suited for this search, which would be conducted mostly with the ground-based apparatus. The short range predicted for these forces means that forces originating in the Earth would not be detectable in orbit. But detection of Yukawa-type exotic forces from a nearby large satellite (such as Space Station) is feasible, and gives a very sensitive and controllable test for little more effort than the orbiting equivalence principle test itself.

  14. Chemical widths at composite interfaces: Relationships to structural widths and methods for measurement

    Energy selected imaging with a Zeiss 912 ?-filter TEM was used to examine grain boundary solute distributions in an Si3N4/SiC(w) ceramic densified with Y2O3 + Al2O3 sintering aid. These results are compared to boundary region solute distributions in the same materials determined by field emission small probe electron energy loss spectroscopy and related methods. The intrinsic higher incident flux of the FEG small probe methods renders them the most useful for high spatial resolution local chemical width measurement. Energy selected imaging is fast and relatively simple for determining elemental distributions in boundaries at low magnifications. The methods are complementary

  15. Approximation of reduced width amplitude and application to cluster decay width

    Kanada-En'yo, Yoshiko; Suhara, Tadahiro; Taniguchi, Yasutaka

    2014-01-01

    We propose a simple method to approximately evaluate reduced width amplitude (RWA) of a two-body spinless cluster channel using the norm overlap with the Brink-Bloch cluster wave function at the channel radius. The applicability of the present approximation is tested for the $^{16}$O+$\\alpha$ channel in $^{20}$Ne as well as the $\\alpha$+$\\alpha$ channel in $^8$Be. The approximation is found to be reasonable to evaluate the RWA for states near the threshold energy and it is useful to estimate ...

  16. A necessary condition for dynamic equivalence

    Pomet, Jean-Baptiste

    2008-01-01

    If two control systems on manifolds of the same dimension are dynamic equivalent, we prove that either they are static equivalent --i.e. equivalent via a classical diffeomorphism-- or they are both ruled; for systems of different dimensions, the one of higher dimension must ruled. A ruled system is one whose equations define at each point in the state manifold, a ruled submanifold of the tangent space. Dynamic equivalence is also known as equivalence by endogenous dynamic feedback, or by a Li...

  17. Crack Width Analysis of Steel Fiber Reinforced Concrete Elements

    Darius Ulbinas

    2011-04-01

    Full Text Available The article investigates the effectiveness of steel fiber reinforcement in RC concrete members in regard to ordinary reinforcement. The advantages and disadvantages of different shapes of steel fibers are discussed. The algorithm for calculating crack width based on EC2 and Rilem methodologies is presented. A comparison of theoretical and experimental crack widths has been performed. The relative errors of crack width predictions at different load levels were defined.Article in Lithuanian

  18. The significance of biometric parameters in determining anterior teeth width

    Strajnić Ljiljana

    2013-01-01

    Full Text Available Background/Aim. An important element of prosthetic treatment of edentulous patients is selecting the size of anterior artificial teeth that will restore the natural harmony of one’s dentolabial structure as well as the whole face. The main objective of this study was to determine the correlation between the inner canthal distance (ICD and interalar width (IAW on one side and the width of both central incisors (CIW, the width of central and lateral incisors (CLIW, the width of anterior teeth (ATW, the width between the canine cusps (CCW, which may be useful in clinical practice. Methods. A total of 89 subjects comprising 23 male and 66 female were studied. Their age ranged from 19 to 34 years with the mean of 25 years. Only the subjects with the preserved natural dentition were included in the sample. All facial and intraoral tooth measurements were made with a Boley Gauge (Buffalo Dental Manufacturing Co., Brooklyn NY, USA having a resolution of 0.1mm. Results. A moderate correlation was established between the interalar width and combined width of anterior teeth and canine cusp width (r = 0.439, r = 0.374. A low correlation was established between the inner canthal distance and the width of anterior teeth and canine cusp width (r = 0.335, r = 0.303. The differences between the two genders were highly significant for all the parameters (p < 0.01. The measured facial distances and width of anterior teeth were higher in men than in women. Conclusion. The results of this study suggest that the examined interalar width and inner canthal distance cannot be considered reliable guidelines in the selection of artificial upper anterior teeth. However, they may be used as a useful additional factor combined with other methods for objective tooth selection. The final decision should be made while working on dentures fitting models with the patient’s consent.

  19. Biologic width and its importance in periodontal and restorative dentistry

    Babitha Nugala; Santosh Kumar, B. B.; S.Sahitya; P Mohana Krishna

    2012-01-01

    An adequate understanding of the relationship between periodontal tissues and restorative dentistry is paramount to ensure adequate form, function, esthetics and comfort of the dentition. While most clinicians are aware of this important relationship, uncertainty remains regarding specific concepts such as biologic width, its maintenance and applications of crown lengthening in cases of biologic width violation. Relevant publications regarding biologic width, its violation and management were...

  20. Sequential Decay Distortion of Goldhaber Model Widths for Spectator Fragments

    Ma, Y.G.; Wada, R; Hagel, K.; Murray, M.; Ono, A.; Wang, J. S.; Qin, L. J.; Makeev, A.; SMITH, P; Natowitz, J. B.

    2002-01-01

    Momentum widths of the primary fragments and observed final fragments have been investigated within the framework of an Antisymmetrized Molecular Dynamics transport model code (AMD-V) with a sequential decay afterburner (GEMINI). It is found that the secondary evaporation effects cause the values of a reduced momentum width, $\\sigma_0$, derived from momentum widths of the final fragments to be significantly less than those appropriate to the primary fragment but close to those observed in man...

  1. Upper limit on the D*(2010) decay width

    We report a measurement of the upper limit of the decay width for the D*+(2010) meson using the High Resolution Spectrometer at PEP. We observed the charged D* production in the decay mode of D*+ → D0π+ with the D0 decaying into the K-π+ mode. The peak in the mass difference distribution M(K-π+π+)-M(K-π+) was used to directly measure the decay width. The width is dominated by the detector resolution and the preliminary result is an upper limit on the full width of Γ/sub D*/ 2 at 90% C.L. 7 refs., 2 figs

  2. On Lower Bounds for Constant Width Arithmetic Circuits

    Arvind, V.; Joglekar, Pushkar S.; Srinivasan, Srikanth

    2009-01-01

    The motivation for this paper is to study the complexity of constant-width arithmetic circuits. Our main results are the following. 1. For every k > 1, we provide an explicit polynomial that can be computed by a linear-sized monotone circuit of width 2k but has no subexponential-sized monotone circuit of width k. It follows, from the definition of the polynomial, that the constant-width and the constant-depth hierarchies of monotone arithmetic circuits are infinite, both in the commutative an...

  3. A Statistical Approach for Obtaining the Controlled Woven Fabric Width

    Shaker Khubab

    2015-12-01

    Full Text Available A common problem faced in fabric manufacturing is the production of inconsistent fabric width on shuttleless looms in spite of the same fabric specifications. Weft-wise crimp controls the fabric width and it depends on a number of factors, including warp tension, temple type, fabric take-up pressing tension and loom working width. The aim of this study is to investigate the effect of these parameters on the fabric width produced. Taguchi’s orthogonal design was used to optimise the weaving parameters for obtaining controlled fabric width. On the basis of signal to noise ratios, it could be concluded that controlled fabric width could be produced using medium temple type and intense take-up pressing tension at relatively lower warp tension and smaller loom working width. The analysis of variance revealed that temple needle size was the most significant factor affecting the fabric width, followed by loom working width and warp tension, whereas take-up pressing tension was least significant of all the factors investigated in the study.

  4. Temperature and spin dependence of the giant dipole resonance width

    The dependence of the GDR width on temperature and spin was investigated in Sn nuclei, by using the reactions 17O + 100Mo and 18O + 100Mo to form 117Sn and 118Sn, respectively. Widths of ?=6.9+/-0.5 MeV and ?=8.2+/-0.5 MeV were extracted for temperatures of 1.74 and 1.84 MeV, respectively. The large increase of the width over this relatively small temperature range is inconsistent with the thermal shape fluctuation model. However, the spin dependence of the width is well reproduced by the model

  5. Sequential Decay Distortion of Goldhaber Model Widths for Spectator Fragments

    Ma, Y G; Hagel, K; Murray, M; Ono, A; Wang, J S; Qin, L J; Makeev, A G; Smith, P; Natowitz, J B

    2002-01-01

    Momentum widths of the primary fragments and observed final fragments have been investigated within the framework of an Antisymmetrized Molecular Dynamics transport model code (AMD-V) with a sequential decay afterburner (GEMINI). It is found that the secondary evaporation effects cause the values of a reduced momentum width, $\\sigma_0$, derived from momentum widths of the final fragments to be significantly less than those appropriate to the primary fragment but close to those observed in many experiments. Therefore, a new interpretation for experiemental momentum widths of projectile-like fragments is presented.

  6. Conformal dynamical equivalence and applications

    Spyrou, N K, E-mail: spyrou@astro.auth.gr [Astronomy Department, Aristoteleion University of Thessaloniki, 541.24 Thessaloniki, Macedonia, Hellas (Greece)

    2011-02-01

    The 'Conformal Dynamical Equivalence' (CDE) approach is briefly reviewed, and some of its applications, at various astrophysical levels (Sun, Solar System, Stars, Galaxies, Clusters of Galaxies, Universe as a whole), are presented. According to the CDE approach, in both the Newtonian and general-relativistic theories of gravity, the isentropic hydrodynamic flows in the interior of a bounded gravitating perfect-fluid source are dynamically equivalent to geodesic motions in a virtual, fully defined fluid source. Equivalently, the equations of hydrodynamic motion in the former source are functionally similar to those of the geodesic motions in the latter, physically, fully defined source. The CDE approach is followed for the dynamical description of the motions in the fluid source. After an observational introduction, taking into account all the internal physical characteristics of the corresponding perfect-fluid source, and based on the property of the isentropic hydrodynamic flows (quite reasonable for an isolated physical system), we examine a number of issues, namely, (i) the classical Newtonian explanation of the celebrated Pioneer-Anomaly effect in the Solar System, (ii) the possibility of both the attractive gravity and the repulsive gravity in a non-quantum Newtonian framework, (iii) the evaluation of the masses - theoretical, dynamical, and missing - and of the linear dimensions of non-magnetized and magnetized large-scale cosmological structures, (iv) the explanation of the flat-rotation curves of disc galaxies, (v) possible formation mechanisms of winds and jets, and (vi) a brief presentation of a conventional approach - toy model to the dynamics of the Universe, characterized by the dominant collisional dark matter (with its subdominant luminous baryonic 'contamination'), correctly interpreting the cosmological observational data without the need of the notions dark energy, cosmological constant, and universal accelerating expansion.

  7. Equivalence Principle in Chameleon Models

    Kraiselburd, Lucila; Landau, Susana. J.; Salgado, Marcelo; Sudarsky, Daniel; Vucetich, Hctor

    2015-01-01

    Most theories that predict time and(or) space variation of fundamental constants also predict violations of the Weak Equivalence Principle (WEP). Khoury and Weltman proposed the chameleon model in 2004 and claimed that this model avoids experimental bounds on the WEP. In this paper we present a contrasting view based on the analysis of the force between two bodies induced by the chameleon field using a particular approach in which the field due to both the large and the small bodies is obtain...

  8. Motor Equivalence in Speech Production

    Perrier, Pascal; Fuchs, Susanne

    2015-01-01

    The first section provides a description of the concepts of “motor equivalence” and “degrees of freedom”. It is illustrated with a few examples of motor tasks in general and of speech production tasks in particular. In the second section, the methodology used to investigate experimentally motor equivalence phenomena in speech production is presented. It is mainly based on paradigms that perturb the perception-action loop during on-going speech, either by limiting the degrees of freedom of the...

  9. Blast Wave Characteristics and Equivalency

    Sochet, Isabelle; Schneider, Helmut

    2010-01-01

    The characteristics of blast waves generated by detonation of gas clouds are studies theoretically and validated by both small-scale and large-scale experiments with ethylene-air mixtures of different equivalence ratio. The mixtures were confined in hemispherical or spherical balloons made from thin polyethylene foils of 0.75 m³ and 15 m³ in volume. The detonation of gas mixtures was initiated by a solid explosive. The characteristics of the blast wave in terms of overpressure, impulse and du...

  10. A Theory of Network Equivalence

    Koetter, Ralf; Medard, Muriel

    2010-01-01

    A family of equivalence tools for bounding network capacities is introduced. For networks of point-to-point channels, the main result is roughly as follows. Given a network of noisy, independent, memoryless point-to-point channels, a collection of demands can be met on the given network if and only if it can be met on another network where each noisy channel is replaced by a noiseless bit pipe with throughput equal to the noisy channel capacity. This result was known previously for the case of a single-source multicast demand. The result given here treats general demands -- including, for example, multiple unicast demands -- and applies even when the achievable rate region for the corresponding demands is unknown in both the noisy network and its noiseless counterpart. The equivalence tools are also used to bound the capacity of networks containing independent channels with multiple transmitters, multiple receivers, or both. In this case, upper and lower bounding models for broadcast, multiple access, and int...

  11. Light WIMPs And Equivalent Neutrinos

    Steigman, Gary

    2014-01-01

    Very light WIMPs (chi), thermal relics that annihilate late in the early Universe, change the energy and entropy densities at BBN and at recombination. BBN, in combination with the CMB, can remove some of the degeneracies among light WIMPs and equivalent neutrinos, constraining the existence and properties of each. Depending on the nature of the light WIMP (Majorana or Dirac fermion, real or complex scalar) the joint BBN + CMB analyses set lower bounds to m_chi in the range 0.5 - 5 MeV (m_chi/m_e > 1 - 10), and they identify best fit values for m_chi in the range 5 - 10 MeV. The joint BBN + CMB analysis finds a best fit value for the number of equivalent neutrinos, Delta N_nu ~ 0.65, nearly independent of the nature of the WIMP. In the absence of a light WIMP (m_chi > 20 MeV), N_eff = 3.05(1 + Delta N_nu /3). In this case, there is excellent agreement between BBN and the CMB, but the joint fit reveals Delta N_nu = 0.40+-0.17, disfavoring standard big bang nucleosynthesis (SBBN) (Delta N_nu = 0) at ~ 2.4 sigma...

  12. Widths of nuclear hole states in a relativistic model

    The relativistic quantum many-body theory of Walecka is used to calculate the widths of hole states in nuclear matter. The results are compared with the observed widths of the holes created in quasifree scattering experiments. The non-relativistic limit is also discussed. (orig.)

  13. Measuring Slit Width and Separation in a Diffraction Experiment

    Gan, K. K.; Law, A. T.

    2009-01-01

    We present a procedure for measuring slit width and separation in single- and double-slit diffraction experiments. Intensity spectra of diffracted laser light are measured with an optical sensor (PIN diode). Slit widths and separations are extracted by fitting to the measured spectra. We present a simple fitting procedure to account for the

  14. Measuring Slit Width and Separation in a Diffraction Experiment

    Gan, K. K.; Law, A. T.

    2009-01-01

    We present a procedure for measuring slit width and separation in single- and double-slit diffraction experiments. Intensity spectra of diffracted laser light are measured with an optical sensor (PIN diode). Slit widths and separations are extracted by fitting to the measured spectra. We present a simple fitting procedure to account for the…

  15. Quantifying River Widths of North America from Satellite Imagery

    Allen, G. H.; Pavelsky, T.; Miller, Z.

    2013-12-01

    River width is a fundamental predictor variable in many hydrologic, geomorphic, and biogeochemical models, yet current large-scale models rely on theoretical hydraulic geometry relationships that do not fully capture natural variability in river form. Here we present the first high-resolution dataset of long-term mean width of North American rivers wider than 30 m. The dataset contains 7.93 million georeferenced width measurements derived from Landsat TM and ETM+ imagery that were acquired when rivers were most likely to be at mean discharge. We built the dataset by developing an automated procedure that selects and downloads raw imagery, creates cloud-free normalized difference water index images, histogram balances and mosaics them together, and produces a water mask using a dynamic water-land threshold technique. We then visually inspected and corrected the mask for errors and used RivWidth software to calculate river width at each river centerline pixel. We validated our dataset using >1000 United States Geological Survey and Water Survey of Canada in situ gauge station measurements. Error analysis shows a robust relationship between the remotely sensed widths and in situ gauge measurements with an r 2 = 0.86 (Spearman's = 0.81) and a mean absolute error of 27.5 m. We find that North American river widths lie on logarithmic frequency curve with some notable exceptions at widths SWOT) satellite mission.

  16. Constant Width Planar Computation Characterizes ACC0

    Hansen, Kristoffer Arnsfelt

    2006-01-01

    We obtain a characterization of ACC0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...

  17. Constant Width Planar Computation Characterizes ACC0

    Hansen, K.A.

    We obtain a characterization of ACC 0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...

  18. Crack widths in concrete with fibers and main reinforcement

    Christensen, Frede; Ulfkjær, Jens Peder; Brincker, Rune

    model to take into account the fiber reinforcement and the pullout of the main reinforcement. By applying suitable kinematics conditions for the fracture band, the deformations within the fracture band correspond to a crack width profile where the crack width varies along the depth of the beam. The......The main object of the research work presented in this paper is to establish design tools for concrete structures where main reinforcement is combined with addition of short discrete steel fibers. The work is concerned with calculating and measuring crack widths in structural elements subjected to...... bending load. Thus, the aim of the work is to enable engineers to calculate crack widths for flexural concrete members and analyze how different combinations of amounts of fibers and amounts of main reinforcement can meet a given maximum crack width requirement. A mathematical model including the...

  19. Crack widths in concrete with fibers and main reinforcement

    Christensen, Frede; Ulfkjr, Jens Peder; Brincker, Rune

    2015-01-01

    The main object of the research work presented in this paper is to establish design tools for concrete structures where main reinforcement is combined with addition of short discrete steel fibers. The work is concerned with calculating and measuring crack widths in structural elements subjected to...... bending load. Thus, the aim of the work is to enable engineers to calculate crack widths for flexural concrete members and analyze how different combinations of amounts of fibers and amounts of main reinforcement can meet a given maximum crack width requirement. A mathematical model including the...... ductility of the fiber reinforced concrete (FRC) is set up and experimental work is conducted in order to verify the crack width model. The ductility of the FRC is taken into account by using the stress crack width relation. The constitutive model for the FRC is based on the idea that the initial part of...

  20. Research on Fairway Width Design in Curved Bridge Waters Channel

    Chi Hong-Fu

    2013-01-01

    Full Text Available Bridge construction can promote economic development but if the bridge layout is unreasonable, it would hinder ship’s safety navigation in the bridge area. There is little reference for fairway width design about curved bridge channel in 〈〈inland river navigation standards〉〉 of China. In this study, a fairway width design method in curved bridge channel was put forward by taking into account the scope of turbulent scope of pier, ship’s track width, drifting distance due to wind, drifting distance due to current, the scope of ship’s safety field and additional width in curved channel. The fairway width design concept for curved bridge channel presented in this studyit may provide reference for bridge design and other fairway layout.

  1. Expanding the Interaction Equivalency Theorem

    Brenda Cecilia Padilla Rodriguez

    2015-06-01

    Full Text Available Although interaction is recognised as a key element for learning, its incorporation in online courses can be challenging. The interaction equivalency theorem provides guidelines: Meaningful learning can be supported as long as one of three types of interactions (learner-content, learner-teacher and learner-learner is present at a high level. This study sought to apply this theorem to the corporate sector, and to expand it to include other indicators of course effectiveness: satisfaction, knowledge transfer, business results and return on expectations. A large Mexican organisation participated in this research, with 146 learners, 30 teachers and 3 academic assistants. Three versions of an online course were designed, each emphasising a different type of interaction. Data were collected through surveys, exams, observations, activity logs, think aloud protocols and sales records. All course versions yielded high levels of effectiveness, in terms of satisfaction, learning and return on expectations. Yet, course design did not dictate the types of interactions in which students engaged within the courses. Findings suggest that the interaction equivalency theorem can be reformulated as follows: In corporate settings, an online course can be effective in terms of satisfaction, learning, knowledge transfer, business results and return on expectations, as long as (a at least one of three types of interaction (learner-content, learner-teacher or learner-learner features prominently in the design of the course, and (b course delivery is consistent with the chosen type of interaction. Focusing on only one type of interaction carries a high risk of confusion, disengagement or missed learning opportunities, which can be managed by incorporating other forms of interactions.

  2. From body burden to effective dose equivalent

    The necessary data to calculate the effective committed dose equivalent and the effective dose-equivalent rate from measured body burdens are presented. Both ingestion and inhalation intakes are considered, for single intake as well as for continuous exposure

  3. 20 CFR 404.1526 - Medical equivalence.

    2010-04-01

    ... medical equivalence. For cases in the disability hearing process or otherwise decided by a disability hearing officer, the responsibility for determining medical equivalence rests with either the disability hearing officer or, if the disability hearing officer's reconsideration determination is changed...

  4. A Discrete Equivalent of the Logistic Equation

    Petropoulou EugeniaN

    2010-01-01

    A discrete equivalent and not analogue of the well-known logistic differential equation is proposed. This discrete equivalent logistic equation is of the Volterra convolution type, is obtained by use of a functional-analytic method, and is explicitly solved using the -transform method. The connection of the solution of the discrete equivalent logistic equation with the solution of the logistic differential equation is discussed. Also, some differences of the discrete equivalent logistic equa...

  5. Discovering Classes of Strongly Equivalent Logic Programs

    Chen, Y; F. Lin

    2011-01-01

    In this paper we apply computer-aided theorem discovery technique to discover theorems about strongly equivalent logic programs under the answer set semantics. Our discovered theorems capture new classes of strongly equivalent logic programs that can lead to new program simplification rules that preserve strong equivalence. Specifically, with the help of computers, we discovered exact conditions that capture the strong equivalence between a rule and the empty set, between two rules, between t...

  6. On the unidimensional fuzzy equivalence relations

    Boixader Ibez, Dions

    1999-01-01

    The dimension of a fuzzy equivalence relation is the minimum number of fuzzy sets needed to generate it. A general theorem is proved that characterizes unidimensional fuzzy equivalence relations. The multidimensional case is also studied under some restrictive conditions (regular fuzzy equivalence relations).

  7. On Revenue Equivalence in Truthful Mechanisms

    Heydenreich, Birgit; Müller, Rudolf; Uetz, Marc; Vohra, Rakesh

    2007-01-01

    The property of an allocation rule to be implementable in dominant strategies by a unique payment scheme is called revenue equivalence. In this paper we give a characterization of revenue equivalence based on a graph theoretic interpretation of the incentive compatibility constraints. The characterization holds for any (possibly infinite) outcome space and many of the known results about revenue equivalence are immediate consequences.

  8. An equivalent sample circuit based on DSP

    The author introduced an equivalent sample circuit which is based on DSP. With the technology of equivalent sample this circuit can sample signal with maximum 10 GHz equivalent sample rate under the condition of 40 MHz single-shot sample rate. The author describes the design theory and its advantage

  9. Classroom Activities for Introducing Equivalence Relations

    Brandt, Jim

    2013-01-01

    Equivalence relations and partitions are two interconnected ideas that play important roles in advanced mathematics. While students encounter the informal notion of equivalence in many courses, the formal definition of an equivalence relation is typically introduced in a junior level transition-to-proof course. This paper reports the results of a

  10. Equivalence in Bilingual Lexicography: Criticism and Suggestions*

    Herbert Ernst Wiegand

    2011-10-01

    Full Text Available

    Abstract: A reminder of general problems in the formation of terminology, as illustrated by theGerman quivalence (Eng. equivalence and quivalent (Eng. equivalent, is followed by a critical discussionof the concept of equivalence in contrastive lexicology. It is shown that especially the conceptof partial equivalence is contradictory in its different manifestations. Consequently attemptsare made to give a more precise indication of the concept of equivalence in the metalexicography,with regard to the domain of the nominal lexicon. The problems of especially the metalexicographicconcept of partial equivalence as well as that of divergence are fundamentally expounded.In conclusion the direction is indicated to find more appropriate metalexicographic versions of theconcept of equivalence.

    Keywords: EQUIVALENCE, LEXICOGRAPHIC EQUIVALENT, PARTIAL EQUIVALENCE,CONGRUENCE, DIVERGENCE, CONVERGENCE, POLYDIVERGENCE, SYNTAGM-EQUIVALENCE,ZERO EQUIVALENCE, CORRESPONDENCE

    Abstrakt: quivalenz in der zweisprachigen Lexikographie: Kritik und Vorschlge.Nachdem an allgemeine Probleme der Begriffsbildung am Beispiel von dt. quivalenzund dt. quivalent erinnert wurde, wird zunchst auf quivalenzbegriffe in der kontrastiven Lexikologiekritisch eingegangen. Es wird gezeigt, dass insbesondere der Begriff der partiellen quivalenzin seinen verschiedenen Ausprgungen widersprchlich ist. Sodann werden Przisierungenzu den quivalenzbegriffen in der Metalexikographie versucht, die sich auf den Bereich der Nennlexikbeziehen. Insbesondere der metalexikographische Begriff der partiellen quivalenz sowie derder Divergenz werden grundstzlich problematisiert. In welche Richtung man gehen kann, umangemessenere metalexikographische Fassungen des quivalenzbegriffs zu finden, wird abschlieendangedeutet.

    Stichwrter: QUIVALENZ, LEXIKOGRAPHISCHES QUIVALENT, PARTIELLE QUIVALENZ,KONGRUENZ, DIVERGENZ, KONVERGENZ, POLYDIVERGENZ, SYNTAGMENQUIVALENZ,NULLQUIVALENZ, KORRESPONDENZ

  11. Nuclear widths and level shifts of a dt? mesic molecule

    Nuclear widths GITAsup(Jv) and shifts ?Esup(Jv) of dt? mesic molecule levels (Jv) due to dt s-wave resonant interaction are expressed through the d+t ? n+4He reaction cross section. It is established that the nuclear resonance 5He*(3+/2) weakly influences the spectrum of mesic molecule because of the small probability of dt being inside the range of nuclear forces in the dt?-molecule and the big inelastic width of the resonance. The nuclear widths and shifts calculated agree well with the results obtained with the generalized optical potential corresponding to the two coupled channels (dt-n4He) problem

  12. Probing eigenfunction nonorthogonality by parametric shifts of resonance widths

    Savin, D V

    2013-01-01

    Recently, it has been shown that the change of resonance widths in an open system under a perturbation of its interior is a sensitive indicator of the nonorthogonality of resonance states. We apply this measure to quantify parametric motion of the resonances. In particular, a strong redistribution of the widths is linked with the maximal degree of nonorthogonality. Then for weakly open chaotic systems we discuss the role of spectral rigidity on the statistical properties of the parametric width shifts, and derive the distribution of the latter in a picket-fence model with equidistant spectrum.

  13. Nightside studies of coherent HF Radar spectral width behaviour

    E. E. Woodfield

    Full Text Available A previous case study found a relationship between high spectral width measured by the CUTLASS Finland HF radar and elevated electron temperatures observed by the EISCAT and ESR incoherent scatter radars in the post-midnight sector of magnetic local time. This paper expands that work by briefly re-examining that interval and looking in depth at two further case studies. In all three cases a region of high HF spectral width (>200 ms-1 exists poleward of a region of low HF spectral width (<200 ms-1. Each case, however, occurs under quite different geomagnetic conditions. The original case study occurred during an interval with no observed electrojet activity, the second study during a transition from quiet to active conditions with a clear band of ion frictional heating indicating the location of the flow reversal boundary, and the third during an isolated sub-storm. These case studies indicate that the relationship between elevated electron temperature and high HF radar spectral width appears on closed field lines after 03:00 magnetic local time (MLT on the nightside. It is not clear whether the same relationship would hold on open field lines, since our analysis of this relationship is restricted in latitude. We find two important properties of high spectral width data on the nightside. Firstly the high spectral width values occur on both open and closed field lines, and secondly that the power spectra which exhibit high widths are both single-peak and multiple-peak. In general the regions of high spectral width (>200 ms-1 have more multiple-peak spectra than the regions of low spectral widths whilst still maintaining a majority of single-peak spectra. We also find that the region of ion frictional heating is collocated with many multiple-peak HF spectra. Several mechanisms for the generation of high spectral width have been proposed which would produce multiple-peak spectra, these are discussed in relation to the data presented here. Since the regions of high spectral width are observed both on closed and open field lines the use of the boundary between low and high spectral width as an ionospheric proxy for the open/closed field line boundary is not a simple matter, if indeed it is possible at all.

    Key words. Ionosphere (auroral ionosphere; ionospheric irregularities

  14. Influence of pulse width and detuning on coherent phonon generation

    Nakamura, Kazutaka G.; Shikano, Yutaka; Kayanuma, Yosuke

    2015-10-01

    We investigated the coherent phonon generation mechanism by irradiation of an ultrashort pulse with a simple two-level model. Our derived formulation shows that both impulsive stimulated Raman scattering (ISRS) and impulsive absorption (IA) simultaneously occur, and phonon wave packets are generated in the electronic ground and excited states by ISRS and IA, respectively. We identify the dominant process from the amplitude of the phonon oscillation. For short pulse widths, ISRS is very small and becomes larger as the pulse width increases. We also show that the initial phase is dependent on the pulse width and the detuning.

  15. The effect of buffer zone width on biodiversity

    Navntoft, Søren; Sigsgaard, Lene; Kristensen, Kristian; Esbjerg, P

    Field margin management for conservation purposes is a way to protect both functional biodiversity and biodiversity per se without considerable economical loss as field margins are less productive. However, the effect of width of the buffer zone on achievable biodiversity gains has received little...... attention in previous studies. In this paper we report on finding for syrphids, spiders and carabids, three taxonomic groups with different mobility, all important for conservation biological control. For all groups we found an effect of buffer zone width on their density. A buffer width of 6m was the...

  16. Research on Fairway Width Design in Curved Bridge Waters Channel

    Chi Hong-Fu; Wang Yuan-Jiao

    2013-01-01

    Bridge construction can promote economic development but if the bridge layout is unreasonable, it would hinder ship’s safety navigation in the bridge area. There is little reference for fairway width design about curved bridge channel in 〈〈inland river navigation standards〉〉 of China. In this study, a fairway width design method in curved bridge channel was put forward by taking into account the scope of turbulent scope of pier, ship’s track width, drifting distance due to wind, drifting dist...

  17. Equivalence Principle in Chameleon Models

    Kraiselburd, Lucila; Salgado, Marcelo; Sudarsky, Daniel; Vucetich, Héctor

    2015-01-01

    Most theories that predict time and(or) space variation of fundamental constants also predict violations of the Weak Equivalence Principle (WEP). Khoury and Weltman proposed the chameleon model in 2004 and claimed that this model avoids experimental bounds on the WEP. In this paper we present a contrasting view based on the analysis of the force between two bodies induced by the chameleon field using a particular approach in which the field due to both the large and the small bodies is obtained by appropriate series expansions in the various regions of interest and the corresponding matching conditions. We found that resulting force depends on the test body\\'{}s composition even when the chameleon coupling constants $\\beta_{i}$ are universal. In particular, we compared the resulting differential acceleration of test bodies made of Be and Al with the corresponding bounds obtained from E\\"otv\\"os type experiments and find that the predictions of the chameleon model are, in general, various orders of magnitude a...

  18. GLACE survey: OSIRIS/GTC Tuneable Filter H$\\alpha$ imaging of the rich galaxy cluster ZwCl 0024.0+1652 at z = 0.395. Part I -- Survey presentation, TF data reduction techniques and catalogue

    Sánchez-Portal, Miguel; Pérez-Martínez, Ricardo; Cepa, Jordi; García, Ana M Pérez; Domínguez-Sánchez, Helena; Bongiovanni, Ángel; Serra, Ana L; Alfaro, Emilio; Altieri, Bruno; Aragón-Salamanca, Alfonso; Balkowski, Chantal; Biviano, Andrea; Bremer, Malcom; Castander, Francisco; Castañeda, Héctor; Castro-Rodríguez, Nieves; Chies-Santos, Ana L; Coia, Daniela; Diaferio, Antonaldo; Duc, Pierre-Alain; Ederoclite, Alessandro; Geach, James; González-Serrano, Ignacio; Haines, Chris P; McBreen, Brian; Metcalfe, Leo; Oteo, Iván; Pérez-Fournón, Ismael; Poggianti, Bianca; Polednikova, Jana; Ramón-Pérez, Marina; Rodríguez-Espinosa, José M; Santos, Joana S; Smail, Ian; Smith, Graham P; Temporin, Sonia; Valtchanov, Ivan

    2015-01-01

    The cores of clusters at 0 $\\lesssim$ z $\\lesssim$ 1 are dominated by quiescent early-type galaxies, whereas the field is dominated by star-forming late-type ones. Galaxy properties, notably the star formation (SF) ability, are altered as they fall into overdense regions. The critical issues to understand this evolution are how the truncation of SF is connected to the morphological transformation and the responsible physical mechanism. The GaLAxy Cluster Evolution Survey (GLACE) is conducting a study on the variation of galaxy properties (SF, AGN, morphology) as a function of environment in a representative sample of clusters. A deep survey of emission line galaxies (ELG) is being performed, mapping a set of optical lines ([OII], [OIII], H$\\beta$ and H$\\alpha$/[NII]) in several clusters at z $\\sim$ 0.40, 0.63 and 0.86. Using the Tunable Filters (TF) of OSIRIS/GTC, GLACE applies the technique of TF tomography: for each line, a set of images at different wavelengths are taken through the TF, to cover a rest fra...

  19. Neutron-induced background by an alpha-beam incident on a deuterium gas target and its implications for the study of the 2H(alpha,gamma)6Li reaction at LUNA

    Anders, M; Bellini, A; Aliotta, M; Bemmerer, D; Broggini, C; Caciolli, A; Costantini, H; Corvisiero, P; Davinson, T; Elekes, Z; Erhard, M; Formicola, A; Fülöp, Zs; Gervino, G; Guglielmetti, A; Gustavino, C; Gyürky, Gy; Junker, M; Lemut, A; Marta, M; Mazzocchi, C; Menegazzo, R; Prati, P; Alvarez, C Rossi; Scott, D; Somorjai, E; Straniero, O; Szücs, T

    2013-01-01

    The production of the stable isotope Li-6 in standard Big Bang nucleosynthesis has recently attracted much interest. Recent observations in metal-poor stars suggest that a cosmological Li-6 plateau may exist. If true, this plateau would come in addition to the well-known Spite plateau of Li-7 abundances and would point to a predominantly primordial origin of Li-6, contrary to the results of standard Big Bang nucleosynthesis calculations. Therefore, the nuclear physics underlying Big Bang Li-6 production must be revisited. The main production channel for Li-6 in the Big Bang is the 2H(alpha,gamma)6Li reaction. The present work reports on neutron-induced effects in a high-purity germanium detector that were encountered in a new study of this reaction. In the experiment, an {\\alpha}-beam from the underground accelerator LUNA in Gran Sasso, Italy, and a windowless deuterium gas target are used. A low neutron flux is induced by energetic deuterons from elastic scattering and, subsequently, the 2H(d,n)3He reaction....

  20. Video digitizer (real time-frame grabber) with region of interest suitable for quantitative data analysis used on the infrared and H alpha cameras installed on the DIII-D experiment

    This paper describes a CAMAC based video digitizer with region of interest (ROI) capability that was designed for use with the infrared and H alpha cameras installed by Lawrence Livermore Laboratory on the DIII-D experiment at G.A. Technologies in San Diego, California. The video digitizer uses a custom built CAMAC video synchronizer module to clock data into a CAMAC transient recorder on a line-by-line basis starting at the beginning of a field. The number of fields that are recorded is limited only by the available transient recorder memory. In order to conserve memory, the CAMAC video synchronizer module provides for the alternative selection of a specific region of interest in each successive field to be recorded. Memory conservation can be optimized by specifying lines in the field, start time, stop time, and the number of data samples per line. This video frame grabber has proved versatile for capturing video in such diverse applications as recording video fields from a video tape recorder played in slow motion or recording video fields in real time during a DIII-D shot. In other cases, one or more lines of video are recorded per frame to give a cross sectional slice of the plasma. Since all the data in the digitizer memory is synchronized to video fields and lines, the data can be read directly into the control computer in the proper matrix format to facilitate rapid processing, display, and permanent storage

  1. A large, multi-epoch H{\\alpha} survey at z=2.23, 1.47, 0.84 & 0.40: the 11 Gyr evolution of star-forming galaxies from HiZELS

    Sobral, David; Best, Philip N; Geach, James E; Matsuda, Yuichi; Stott, John P; Cirasuolo, Michele; Kurk, Jaron

    2012-01-01

    This paper presents new deep and wide narrow-band surveys undertaken with UKIRT, Subaru and the VLT; a unique combined effort to select large, robust samples of H-alpha (Ha) emitters at z=0.40, 0.84, 1.47 and 2.23 (corresponding to look-back times of 4.2, 7.0, 9.2 and 10.6 Gyrs) in a uniform manner over ~2 deg^2 in the COSMOS and UDS fields. The deep multi-epoch Ha surveys reach ~3M_sun/yr out to z=2.2 for the first time, while the wide area and the coverage over two independent fields allow to greatly overcome cosmic variance. A total of 1742, 637, 515 and 556 Ha emitters are homogeneously selected at z=0.40, 0.84, 1.47 and 2.23, respectively, and used to determine the Ha luminosity function and its evolution. The faint-end slope is found to be -1.60+-0.08 over z=0-2.23, showing no evolution. The characteristic luminosity of SF galaxies, L*, evolves significantly as log[L*(z)]=0.45z+log[L*(z=0)]. This is the first time Ha has been used to trace SF activity with a single homogeneous survey at z=0.4-2.23. Over...

  2. Intraresidue 1H-15N-13C' and 1H alpha-13C alpha-13C' dipole-CSA relaxation interference as a source of constraints for structural refinement of metal-binding sites in zinc-finger proteins.

    Kloiber, K; Schler, W; Konrat, R

    2001-04-01

    1H(i)-15 N(i)-13C'(i) dipole-chemical shift anisotropy (CSA) relaxation interference was quantified for the 13C,15N labeled zinc-finger protein qCRP2(LIM2). The cross-correlation rates obtained for residues located in the metal coordination sites of qCRP2(LIM2) show a high degree of correlation with the peptide plane torsion angles phi and psi taken from the solution structure. 1H(i)-15N(i)-13C'(i) as well as 13C alpha(i)-1H alpha(i)-13C'(i) dipole-CSA cross-correlation rates were subsequently used to improve the geometry of the metal binding site. The optimized dihedral angles of the two zinc-binding sites in qCRP2(LIM2) are in better agreement with values obtained from crystal structures of other zinc-finger proteins and thus establish the utility of this approach to improve the metal-binding site geometry of zinc-finger proteins studied by NMR spectroscopy in solution. PMID:11370780

  3. Better Polynomial Algorithms on Graphs of Bounded Rank-Width

    Ganian, Robert; Hliněný, Petr

    Although there exist many polynomial algorithms for NP-hard problems running on a bounded clique-width expression of the input graph, there exists only little comparable work on such algorithms for rank-width. We believe that one reason for this is the somewhat obscure and hard-to-grasp nature of rank-decompositions. Nevertheless, strong arguments for using the rank-width parameter have been given by recent formalisms independently developed by Courcelle and Kanté, by the authors, and by Bui-Xuan et al. This article focuses on designing formally clean and understandable "pseudopolynomial" (XP) algorithms solving "hard" problems (non-FPT) on graphs of bounded rank-width. Those include computing the chromatic number and polynomial or testing the Hamiltonicity of a graph and are extendable to many other problems.

  4. Widths of some classes of convex functions and bodies

    We consider classes of uniformly bounded convex functions defined on convex compact bodies in Rd and satisfying a Lipschitz condition and establish the exact orders of their Kolmogorov, entropy, and pseudo-dimension widths in the L1-metric. We also introduce the notions of pseudo-dimension and pseudo-dimension widths for classes of sets and determine the exact orders of the entropy and pseudo-dimension widths of some classes of convex bodies in Rdrelative to the pseudo-metric defined as the d-dimensional Lebesgue volume of the symmetric difference of two sets. We also find the exact orders of the entropy and pseudo-dimension widths of the corresponding classes of characteristic functions in Lp-spaces, 1≤p≤∞.

  5. Calculation of the decay width of decuplet baryons

    Alexandrou, Constantia; Petschlies, Marcus; Pochinsky, Andrew V; Syritsyn, Sergey S

    2015-01-01

    We calculate the coupling constant and decay width of the decuplet to octet baryon transitions in lattice QCD using the transfer matrix method. The transition amplitude is related to the coupling constant and via the Fermi's Golden Rule to the decay width. The method is applicable for near-degeneracy of the energy levels of initial and final states and, when this condition is fulfilled, yields a good estimate of the decay width. We present results using a hybrid action with domain wall valence quarks on a staggered sea with $350$ MeV pion mass as well as for a domain wall fermion action with $180$ MeV pion mass. We find $\\Gamma\\left( \\Delta \\to \\pi\\,N \\right) = 119\\,( 8)\\,( 8)$ MeV for the transition of Delta to pion-nucleon within the unitary domain wall setup. We also report values for the decay widths of the $\\Sigma^*$ and $\\Xi*$ baryons.

  6. Systematics of oscillatory behavior in hadronic masses and widths

    Tatischeff, Boris

    2016-01-01

    A systematic study of hadron masses and widths shows regular oscillations that can be fitted by a simple cosine function. This property can be observed when the difference between adjacent masses of each family is plotted versus the mean mass.

  7. Optical waveguide device with an adiabatically-varying width

    Watts; Michael R. , Nielson; Gregory N.

    2011-05-10

    Optical waveguide devices are disclosed which utilize an optical waveguide having a waveguide bend therein with a width that varies adiabatically between a minimum value and a maximum value of the width. One or more connecting members can be attached to the waveguide bend near the maximum value of the width thereof to support the waveguide bend or to supply electrical power to an impurity-doped region located within the waveguide bend near the maximum value of the width. The impurity-doped region can form an electrical heater or a semiconductor junction which can be activated with a voltage to provide a variable optical path length in the optical waveguide. The optical waveguide devices can be used to form a tunable interferometer (e.g. a Mach-Zehnder interferometer) which can be used for optical modulation or switching. The optical waveguide devices can also be used to form an optical delay line.

  8. Unprecedented grain size effect on stacking fault width

    A. Hunter

    2013-09-01

    Full Text Available Using an atomistic-phase field dislocation dynamics model, we isolate and investigate grain size and stress effects on the stacking fault width created by partial dislocation emission from a boundary. We show that the nucleation stress for a Shockley partial is governed by size of the boundary defect and insensitive to grain size. We reveal a grain size regime in which the maximum value the stacking fault width attains increases with grain size.

  9. Bone Mineral Density Value Dependence on Bone Width

    M. Mokhtari-Dizaji

    2006-05-01

    Full Text Available Dual x-ray absorptiometry (DXA is the most widely used measurement for the assessment of bone mass in osteoporosis. In clinical measurement, bone width can affect bone mineral parameters. The purpose of this study was to examine the dependence of bone mineral pa-rameters on bone width. In this study, DXA measurements were conducted on rabbit bone in vivo using clinical instruments. We have selected rabbit’s bones that have low BMD and more collagen tissue to predict structure not only measures BMD, but is also sensitive to the structure of the bone. To investigate the effect of bone width on the measured parameters, three regions of femur and tibia bones (N=132 were processed: upper (1/3 of length, middle (1/2 of length and lower (2/3 of length for BMC, areal BMD and volumetric BMD. The ANOVA analysis of bone mineral extracted by DXA showed significant differences (P<0.05 between BMC, BMDa and BMDv of six groups of upper, middle and lower parts of the femur and the tibia. It shows that BMC and BMD correlate well with the bone width, but BMDv inversely correlates with bone width. Linear and nonlinear regression analyses were used to examine the relationship between DXA characteristics with bone width and the regression function for each parameter is given. We concluded that BMC, areal BMD, and volumetric BMD in rabbit's bone with collagen fibers more than bone mineral are dependent on bone width. This result may be at least in part due to large precision error measurement of the bone width, in vivo.

  10. Solar Imagery - GONG (H-alpha)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Oscillation Network Group (GONG) is a network of 6 globally-spaced solar observatories that the NOAA Space Weather Prediction Center uses to monitor the...

  11. Laryngeal air column width ratio in predicting post extubation stridor

    Pradeep M Venkategowda

    2015-01-01

    Full Text Available Aim: Correlation of upper air column width ratio in postextubation stridor patients. Materials and Methods: A prospective observational study was conducted in a tertiary hospital between January and December 2013. Patients who were admitted in Intensive Care Unit and intubated for >24 h were included (72 patients. The upper airway air column width ratio (air column width before extubation/air column width after intubation was calculated and compared in patient with or without postextubation stridor. Results: The incidence of stridor was 6.9% (5/72. The duration of mechanical ventilation was 5.60 1.14 days and 3.91 1.45 days in stridor and nonstridor group respectively. In all 5 patients who had stridor, the upper airway air column width ratio was 0.8 or less. Conclusion: Air column width ratio of 0.8 or less may be helpful in predicting postextubation stridor, which should be confirmed by large observational studies.

  12. Crack width monitoring of concrete structures based on smart film

    Due to its direct link to structural security, crack width is thought to be one of the most important parameters reflecting damage conditions of concrete structures. However, the width problem is difficult to solve with the existing structural health monitoring methods. In this paper, crack width monitoring by means of adhering enameled copper wires with different ultimate strains on the surface of structures is proposed, based on smart film crack monitoring put forward by the present authors. The basic idea of the proposed method is related to a proportional relationship between the crack width and ultimate strain of the broken wire. Namely, when a certain width of crack passes through the wire, some low ultimate strain wires will be broken and higher ultimate strain wires may stay non-broken until the crack extends to a larger scale. Detection of the copper wire condition as broken or non-broken may indicate the width of the structural crack. Thereafter, a multi-layered stress transfer model and specimen experiment are performed to quantify the relationship. A practical smart film is then redesigned with this idea and applied to Chongqing Jiangjin Yangtze River Bridge. (paper)

  13. Equivalences Among Aggregate Queries with Negation

    Cohen, S; Sagiv, Y; Cohen, Sara; Nutt, Werner; Sagiv, Yehoshua

    2002-01-01

    Query equivalence is investigated for disjunctive aggregate queries with negated subgoals, constants and comparisons. A full characterization of equivalence is given for the aggregation functions count, max, sum, prod, toptwo and parity. A related problem is that of determining, for a given natural number N, whether two given queries are equivalent over all databases with at most N constants. We call this problem bounded equivalence. A complete characterization of decidability of bounded equivalence is given. In particular, it is shown that this problem is decidable for all the above aggregation functions as well as for count distinct and average. For quasilinear queries (i.e., queries where predicates that occur positively are not repeated) it is shown that equivalence can be decided in polynomial time for the aggregation functions count, max, sum, parity, prod, toptwo and average. A similar result holds for count distinct provided that a few additional conditions hold. The results are couched in terms of ab...

  14. On Projective Equivalence of Univariate Polynomial Subspaces

    Peter Crooks

    2009-12-01

    Full Text Available We pose and solve the equivalence problem for subspaces of P_n, the (n+1 dimensional vector space of univariate polynomials of degree ≤ n. The group of interest is SL_2 acting by projective transformations on the Grassmannian variety G_kP_n of k-dimensional subspaces. We establish the equivariance of the Wronski map and use this map to reduce the subspace equivalence problem to the equivalence problem for binary forms.

  15. Equivalent Simplification Method of Micro-Grid

    Cai Changchun; Cao Xiangqin

    2013-01-01

    The paper concentrates on the equivalent simplification method for the micro-grid system connection into distributed network. The equivalent simplification method proposed for interaction study between micro-grid and distributed network. Micro-grid network, composite load, gas turbine synchronous generation, wind generation are equivalent simplification and parallel connect into the point of common coupling. A micro-grid system is built and three phase and single phase grounded faults are per...

  16. The Complexity of Identifying Large Equivalence Classes

    Skyum, Sven; Frandsen, Gudmund Skovbjerg; Miltersen, Peter Bro; Binderup, Peter G.

    We prove that at least 3k−4/k(2k−3)(n/2) – O(k)equivalence tests and no more than 2/k (n/2) + O(n) equivalence tests are needed in the worst case to identify the equivalence classes with at least k members in set of n elements. The upper bound is an improvement by a factor 2 compared to known res...

  17. Is the principle of equivalence a principle?

    Bozhidar Z. Iliev

    1998-01-01

    The work argues the principle of equivalence to be a theorem and not a principle (in a sense of an axiom). It contains a detailed analysis of the concepts of normal and inertial frame of reference. The equivalence principle is proved to be valid (at every point and along every path) in any gravitational theory based on linear connections. Possible generalizations of the equivalence principle are pointed out.

  18. Dose equivalent measurements on board civil aircraft

    The ambient dose equivalent in the mixed radiation field on board civil aircraft was determined with a total relative uncertainty of 20%, using a tissue-equivalent proportional counter. The measured dose equivalent rates for flight levels 330 to 410 (corresponding to flight altitudes from 9.9 km to 12.3 km) range from 4 to 8 ?Sv/h. Information on the components of the radiation fields was obtained and special investigations with various absorber materials were performed. (orig.)

  19. Enhanced effects of the Lorentz invariance and Einstein equivalence principle violation in 229Th nuclear transition

    Flambaum, V V

    2015-01-01

    The Lorentz invariance and Einstein equivalence principle violating effects in the narrow 7.8 eV transition in 229Th nucleus may be 100 000 times larger than in atoms. This transition may be investigated using high precision laser spectroscopy methods, has a very small width, and suppressed systematic effects. Similar values of the effects are expected in 73 eV 235U nuclear transition which is coming within the reach of the laser spectroscopy. Mossbauer transitions give another possibility.

  20. Behavioural equivalence for infinite systems - Partially decidable!

    Sunesen, Kim; Nielsen, Mogens

    For finite-state systems non-interleaving equivalences are computationally at least as hard as interleaving equivalences. In this paper we show that when moving to infinite-state systems, this situation may change dramatically. We compare standard language equivalence for process description...... of Esparza and Kiehn, showing the same phenomenon in the setting of model checking. We follow up investigating to which extent the result extends to larger subsets of CCS and TCSP. We discover a significant difference between our non-interleaving equivalences. We show that for a certain non...

  1. Auto-equivalences of stable module categories

    Dugas, Alex

    2014-01-01

    We construct nontrivial auto-equivalences of stable module categories for elementary, local symmetric algebras over a field k. These auto-equivalences are modeled after the spherical twists of Seidel and Thomas and the $\\mathbb{P}^n$-twists of Huybrechts and Thomas, which yield auto-equivalences of the derived category of coherent sheaves on a variety. For group algebras of p-groups in characteristic p we recover many of the auto-equivalences corresponding to endo-trivial modules. We also obt...

  2. Self-Energy Correction to the Two-Photon Decay Width in Hydrogenlike Atoms

    Jentschura, U D

    2004-01-01

    We investigate the gauge invariance of the leading logarithmic radiative correction to the two-photon decay width in hydrogenlike atoms. It is shown that an effective treatment of the correction using a Lamb-shift "potential" leads to equivalent results in both the length as well as the velocity gauges provided all relevant correction terms are taken into account. Specifically, the relevant radiative corrections are related to the energies that enter into the propagator denominators, to the Hamiltonian, to the wave functions, and to the energy conservation condition that holds between the two photons; the form of all of these effects is different in the two gauges, but the final result is shown to be gauge invariant, as it should be. Although the actual calculation only involves integrations over nonrelativistic hydrogenic Green functions, the derivation of the leading logarithmic correction can be regarded as slightly more complex than that of other typical logarithmic terms. The dominant radiative correctio...

  3. Symphysis pubis width and unaffected hip joint width in patients with slipped upper femoral epiphysis: widening compared with normal values

    Tins, Bernhard; Cassar-Pullicino, Victor; Haddaway, Mike [RJAH Orthopaedic Hospital, Department of Radiology, Shropshire (United Kingdom)

    2010-04-15

    The exact pathomechanism of slipped upper femoral epiphysis (SUFE) remains elusive. This paper suggests a generalised abnormality of the development or maturation of cartilage as a possible cause. It is proposed that SUFE is part of a generalised abnormality of the cartilage formation or maturation resulting in abnormal measurements of cartilaginous joint structures. Radiographs of SUFE patients were assessed for the width of the unaffected hip joint and the symphysis pubis. Comparison with previously published normal values was made. Fifty-one patients were assessed, 35 male, 16 female. The average age was 12 years and 11 months combined for both sexes, 13 years 8 months for boys, 11 years 4 months for girls. Width of the symphysis pubis was assessed on 46 datasets, and comparison with normal values was performed using the Wilcoxon paired rank test. Statistical significance was set as p < 0.05. The average expected width was 5.8 mm (5.4-6.2 mm), the average measured width was 7.3 mm (3.5-12 mm), median value 7.0 mm, and the difference is statistically significant. Cartilage thickness of the uninvolved hip joint could be assessed in 46 cases, and comparison using the Wilcoxon paired rank test resulted in a statistically significant difference (significance set as p < 0.05). The average expected width was 4.9 mm (3.6-6.5 mm), the average measured width was 5.5 mm (4-8 mm), and median 5.3 mm. The results indicate that SUFE patients display a generalised increased width of joint cartilage for their age. This could be due to increased cartilage formation or decreased maturation or a combination of the two, and could explain the increased mechanical vulnerability of these children to normal or abnormal stresses, despite histologically normal organisation of the physis as shown in previous studies. (orig.)

  4. Snow Water Equivalent Reconstruction Using FIA Tree Ring Data

    Barandiaran, D.; Wang, S. Y.; DeRose, R. J.

    2014-12-01

    Tree ring widths have been used as a proxy for climate variables for several decades. Temperature, precipitation, and less commonly, snow water equivalent have been modeled in numerous locations throughout the world. Typical studies use carefully selected trees to maximize length of record and sensitivity to the variable of interest, and result in a reconstruction for a specific location. Here we use tree ring data collected by the Forest Inventory and Analysis (FIA) program, conducted by the U.S. Forest Service to reconstruct snow water equivalent for the state of Utah. This program collects increment cores on a geographically unbiased grid at horizontal resolution of 5-km across the U.S., resulting in an unprecedented sample density of tree ring data, and therefore enabling a reconstruction that covers a large geographic area at a resolution not possible using traditional dendroclimatology methods. Prior work (DeRose et al. 2013) has shown FIA to have coherence with previously published chronologies and with water-year precipitation. Snowpack is a major source of water in the Intermountain West, and yet few tree ring studies have reconstructed SWE and the instrumental record is limited in length, so this reconstruction represents a novel and useful dataset for water users and resource managers alike. Here we present initial results and a preliminary analysis of this unique dataset.

  5. Interatomic Coulombic decay widths of helium trimer: Ab initio calculations

    Koloren?, P?emysl; Sisourat, Nicolas

    2015-12-01

    We report on an extensive study of interatomic Coulombic decay (ICD) widths in helium trimer computed using a fully ab initio method based on the Fano theory of resonances. Algebraic diagrammatic construction for one-particle Green's function is utilized for the solution of the many-electron problem. An advanced and universal approach to partitioning of the configuration space into discrete states and continuum subspaces is described and employed. Total decay widths are presented for all ICD-active states of the trimer characterized by one-site ionization and additional excitation of an electron into the second shell. Selected partial decay widths are analyzed in detail, showing how three-body effects can qualitatively change the character of certain relaxation transitions. Previously unreported type of three-electron decay processes is identified in one class of the metastable states.

  6. Modelling the widths of fission observables in GEF

    Schmidt K.-H.

    2013-03-01

    Full Text Available The widths of the mass distributions of the different fission channels are traced back to the probability distributions of the corresponding quantum oscillators that are coupled to the heat bath, which is formed by the intrinsic degrees of freedom of the fissioning system under the influence of pairing correlations and shell effects. Following conclusion from stochastic calculations of Adeev and Pashkevich, an early freezing due to dynamical effects is assumed. It is shown that the mass width of the fission channels in low-energy fission is strongly influenced by the zero-point motion of the corresponding quantum oscillator. The observed variation of the mass widths of the asymmetric fission channels with excitation energy is attributed to the energy-dependent properties of the heat bath and not to the population of excited states of the corresponding quantum oscillator.

  7. The width of the ? meson in the nuclear medium

    We evaluate the width of the ? meson in nuclear matter. We consider the free decay mode of the ? into three pions, which is dominated by ?? decay, and replace the ? and ? propagators by their medium-modified ones. We also take into account the quasielastic and inelastic processes induced by a vector-baryon interaction dominated by vector meson exchange, as well as the contributions coming from the ??K anti K mechanism with medium-modified K, anti K propagators. We obtain a substantial increase of the ? width in the medium, reaching a value of 121 10 MeV at normal nuclear matter density for an ? at rest, which comes mainly from ?N ? ??N, ?NN ? ?NN processes associated to the dominant ? ? ?? decay mode. The value of the width increases moderately with momentum, reaching values of around 200MeV at 600MeV/c. (orig.)

  8. Analysis on Longitudinal Dose according to Change of Field Width

    To analyze the accuracy of tumor volume dose following field width change, to check the difference of dose change by using self-made moving car, and to evaluate practical delivery tumor dose when tomotherapy in the treatment of organ influenced by breathing. By using self-made moving car, the difference of longitudinal movement (0.0 cm, 1.0 cm, 1.5 cm, 2.0 cm) was applied and compared calculated dose with measured dose according to change of field width (1.05 cm, 2.50 cm, 5.02 cm) and apprehended margin of error. Then done comparative analysis in degree of photosensitivity of DQA film measured by using Gafchromic EBT film. Dose profile and Gamma histogram were used to measure degree of photosensitivity of DQA film. When field width were 1.05 cm, 2.50 cm, 5.02 cm, margin of error of dose delivery coefficient was -2.00%, -0.39%, -2.55%. In dose profile of Gafchromic EBT film's analysis, the movement of moving car had greater motion toward longitudinal direction and as field width was narrower, big error increased considerably at high dose part compared to calculated dose. The more field width was narrowed, gamma index had a large considerable influence of moving at gamma histogram. We could check the difference of longitudinal dose of moving organ. In order to small field width and minimize organ moving due to breathing, it is thought to be needed to develop breathing control unit and fixation tool.

  9. 7 CFR 1032.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1032.54 Section 1032.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1032.54 Equivalent price. See § 1000.54. Producer Price Differential...

  10. 7 CFR 1006.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1006.54 Section 1006.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1006.54 Equivalent price. See § 1000.54. Uniform Prices...

  11. 7 CFR 1030.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1030.54 Section 1030.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1030.54 Equivalent price. See § 1000.54....

  12. 7 CFR 1124.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1124.54 Section 1124.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Class Prices § 1124.54 Equivalent price. See § 1000.54. Producer Price Differential...

  13. 7 CFR 1005.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1005.54 Section 1005.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1005.54 Equivalent price. See § 1000.54. Uniform Prices...

  14. 7 CFR 1007.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1007.54 Section 1007.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1007.54 Equivalent price. See § 1000.54. Uniform Prices...

  15. 7 CFR 1131.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1131.54 Section 1131.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1131.54 Equivalent price. See § 1000.54. Uniform Prices...

  16. 7 CFR 1033.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1033.54 Section 1033.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1033.54 Equivalent price. See § 1000.54. Producer Price Differential...

  17. 7 CFR 1000.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1000.54 Section 1000.54 Agriculture... Prices § 1000.54 Equivalent price. If for any reason a price or pricing constituent required for computing the prices described in § 1000.50 is not available, the market administrator shall use a price...

  18. 7 CFR 1126.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1126.54 Section 1126.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1126.54 Equivalent price. See § 1000.54. Producer Price Differential...

  19. 7 CFR 1001.54 - Equivalent price.

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Equivalent price. 1001.54 Section 1001.54 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Class Prices § 1001.54 Equivalent price. See § 1000.54. Producer Price Differential...

  20. Mania and Behavioral Equivalents: A Preliminary Study

    Sturmey, Peter; Laud, Rinita B.; Cooper, Christopher L.; Matson, Johnny L.; Fodstad, Jill C.

    2010-01-01

    Previous research has failed to address the possibility of behavioral equivalents in people with ID and mania. The relationship between a measure of mania and possible behavioral equivalents was assessed in 693 adults, most with severe or profound ID, living in a large residential setting. The mania subscale of the DASH-II proved to be a

  1. The effective theory of Borel equivalence relations

    Fokina, E.B.; Friedman, S.-D.; Törnquist, Asger Dag

    2010-01-01

    The study of Borel equivalence relations under Borel reducibility has developed into an important area of descriptive set theory. The dichotomies of Silver [20] and Harrington, Kechris and Louveau [6] show that with respect to Borel reducibility, any Borel equivalence relation strictly above equa...

  2. Bisimulations Meet PCTL Equivalences for Probabilistic Automata

    Song, Lei; Zhang, Lijun; Godskesen, Jens Christian

    equivalences are proposed for PAs, asa powerful tool for abstraction and compositional minimization forPAs. Unfortunately, the behavioral equivalencesare well-known to be strictly stronger than the logical equivalences inducedby PCTL or PCTL*. This paper introduces novel notions of strongbisimulation relations...

  3. Efficient algorithms for estimating the width of nearly normal distributions

    Typical physics data samples often conform to Gaussian distributions with admixtures of more slowly varying backgrounds. Under such circumstances the standard deviation is known to be a poor statistical measure of distribution width. As an alternative, the performance of Gini's mean difference is compared with the standard deviation and the mean deviation. Variants which sum over subsets of all possible pairs are shown to have statistical efficiencies comparable to the mean difference and mean deviation but do not require extensive data storage or a priori knowledge of the sample mean. These statistics are reasonable candidates for monitoring the distribution width of a real time data stream. (orig.)

  4. Shift adn width of HeII lines

    Based on a quantum statistical many-particle theory, the shift and the width of some He II lines have been evaluated. Ion dynamics have been treated within the model microfield method. Furthermore, fine structure splitting has been taken into account in order to check whether this effect is the cause for the existing large discrepancies between theoretical and experimental line widths. Besides the electronic contributions to the line shift, the shift due to the inhomogeneities of the ionic microfield as well as that due to the quadratic Stark effect has been included. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  5. Statistical analysis of s-wave neutron reduced widths

    The fluctuations of the s-wave neutron reduced widths for many nuclei have been analyzed with emphasis on recent measurements by a statistical procedure which is based on the method of maximum likelihood. It is shown that the s-wave neutron reduced widths of nuclei follow single channel Porter Thomas distribution (x2-distribution with degree of freedom ν = 1) for most of the cases. However there are apparent deviations from ν = 1 and possible explanation and significance of this deviation is given. These considerations are likely to modify the evaluation of neutron cross section. (author)

  6. Widths of the isobaric analog state of 208Pb

    Both escape and spreading widths are evaluated microscopically in a consistent framework for the isobaric analog of the 206Pb ground state. A TDA Green function is obtained within the space of discretized J=0+ proton-particle neutron-hole configurations using the Skyrme interaction. Couplings of these configurations with continuum and more complicated configurations are included into TDA matrix elements with a form of energy dependent terms. The energy and the widths of the isobaric analog resonance are obtained as a result of the matrix diagonalization. Comparison is made of the results with the former theoretical calculations as well as experimental data. (orig.)

  7. A New Measurement of the $\\pi^0$ Radiative Decay Width

    Larin, I.; McNulty, D.; Clinton, E.; Ambrozewicz, P.; Lawrence, D.; Nakagawa, I.; Y. Prok(Old Dominion University); Teymurazyan, A.; Ahmidouch, A.; A. Asratyan; Baker, K; Benton, L.; Bernstein, A. M.; Burkert, V.; Cole, P.

    2010-01-01

    High precision measurements of the differential cross sections for $\\pi^0$ photoproduction at forward angles for two nuclei, $^{12}$C and $^{208}$Pb, have been performed for incident photon energies of 4.9 - 5.5 GeV to extract the ${\\pi^0 \\to \\gamma\\gamma}$ decay width. The experiment was done at Jefferson Lab using the Hall B photon tagger and a high-resolution multichannel calorimeter. The ${\\pi^0 \\to \\gamma\\gamma}$ decay width was extracted by fitting the measured cross sections using rece...

  8. Calabi-Yau completions and orbifold equivalences

    Carqueville, Nils

    2015-01-01

    Calabi-Yau algebras are particularly symmetric differential graded algebras. There is a construction due to Keller called `Calabi-Yau completion' which produces a canonical Calabi-Yau algebra from any homologically smooth dg algebra. Homologically smooth dg algebras also form a 2-category to which the construction of `equivariant completion' can be applied. In this theory two objects are called `orbifold equivalent' if there is a 1-morphism with invertible quantum dimensions between them. Any such relation entails a whole family of equivalences between categories. We show that Calabi-Yau completion and equivariant completion are compatible. More precisely, we prove that any orbifold equivalence between two homologically smooth and proper dg algebras lifts to an orbifold equivalence between their Calabi-Yau completions. As a corollary we obtain orbifold equivalences between Ginzburg algebras of Dynkin quivers.

  9. Equivalence in Ventilation and Indoor Air Quality

    Sherman, Max; Walker, Iain; Logue, Jennifer

    2011-08-01

    We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

  10. Bisimulations meet PCTL equivalences for probabilistic automata

    Song, Lei; Zhang, Lijun; Godskesen, Jens Chr.; Nielson, Flemming

    2013-01-01

    and complete behavioral equivalence has been pointed out by Segala in [34], but remains open throughout the years. In this paper we introduce novel notions of strong bisimulation relations, which characterize PCTL and PCTL* exactly. We extend weak bisimulations that characterize PCTL and PCTL* without...... extension PCTL*. Various behavioral equivalences are proposed, as a powerful tool for abstraction and compositional minimization for PAs. Unfortunately, the equivalences are well-known to be sound, but not complete with respect to the logical equivalences induced by PCTL or PCTL*. The desire of a both sound...... next operator, respectively. Further, we also extend the framework to simulation preorders. Thus, our paper bridges the gap between logical and behavioral equivalences and preorders in this setting....

  11. Beyond Language Equivalence on Visibly Pushdown Automata

    Srba, Jiří

    2009-01-01

    We study (bi)simulation-like preorder/equivalence checking on the class of visibly pushdown automata and its natural subclasses visibly BPA (Basic Process Algebra) and visibly one-counter automata. We describe generic methods for proving complexity upper and lower bounds for a number of studied preorders and equivalences like simulation, completed simulation, ready simulation, 2-nested simulation preorders/equivalences and bisimulation equivalence. Our main results are that all the mentioned equivalences and preorders are EXPTIME-complete on visibly pushdown automata, PSPACE-complete on visibly one-counter automata and P-complete on visibly BPA. Our PSPACE lower bound for visibly one-counter automata improves also the previously known DP-hardness results for ordinary one-counter automata and one-counter nets. Finally, we study regularity checking problems for visibly pushdown automata and show that they can be decided in polynomial time.

  12. Equivalence-Equivalence Responding: Training Conditions Involved in Obtaining a Stable Baseline Performance

    Garcia, Andres; Bohorquez, Cristobal; Perez, Vicente; Gutierrez, Maria Teresa; Gomez, Jesus; Luciano, Carmen; Wilson, Kelly

    2008-01-01

    Recent research has focused on the variables associated with equivalence-equivalence responding, in which participants match pairs of equivalent or nonequivalent stimuli. One such variable is the presence of response competition from nonarbitrary (physical) relational response options. In the current analysis, the experimenters examined the effect…

  13. The width of gamma-ray burst spectra

    Axelsson, Magnus

    2014-01-01

    The emission processes active in the highly relativistic jets of gamma-ray bursts (GRBs) remain unknown. In this paper we propose a new measure to describe spectra: the width of the $EF_E$ spectrum, a quantity dependent only on finding a good fit to the data. We apply this to the full sample of GRBs observed by Fermi/GBM and CGRO/BATSE. The results from the two instruments are fully consistent. We find that the median widths of spectra from long and short GRBs are significantly different (chance probability $<10^{-6}$). The width does not correlate with either duration or hardness, and this is thus a new, independent distinction between the two classes. Comparing the measured spectra with widths of spectra from fundamental emission processes -- synchrotron and blackbody radiation -- the results indicate that a large fraction of GRB spectra are too narrow to be explained by synchrotron radiation from a distribution of electron energies: for example, 78% of long GRBs and 85% of short GRBs are incompatible wi...

  14. Factors determining spectral width of HF echoes from high latitudes

    P. V. Ponomarenko

    2007-03-01

    Full Text Available Spectral width is one of the standard data types produced by the Super Dual Auroral Radar Network (SuperDARN. A pronounced latitudinal gradient in spectral width has been reported in the literature and is used as an empirical proxy for the ionospheric footprint of the open-closed field-line boundary. In this work we investigated the daytime radar echo properties near the spectral width boundary using a multi-frequency sounding regime. We have found that the relatively large spectral width values ≥150 m/s observed poleward of the boundary are produced by ionospheric irregularities with lifetime τl≃10–25 ms, which is essentially independent of the scale size. These irregularities are statistically co-located with low-energy (~100 eV electron precipitation, which may play a major role in producing F-region turbulence above 75 MLAT via restructuring the ionospheric plasma on time scales ~τl.

  15. Dynamical Screening of Atom Confined by Finite-Width Fullerene

    Lo, S; Korol, A. V.; Solov'yov, A V

    2007-01-01

    This is an investigation on the dynamical screening of an atom confined within a fullerene of finite width. The two surfaces of the fullerene lead to the presence of two surface plasmon eigenmodes. It is shown that, in the vicinity of these two eigenfrequencies, there is a large enhancement of the confined atom's photoabsorption rate.

  16. On the width of collective excitations in chiral soliton models

    In chiral soliton models for baryons the computation of hadronic decay widths of baryon resonances is a long standing problem. For the three flavor Skyrme model I present a solution to this problem that satisfies large-NC consistency conditions. As an application I focus on the hadronic decay of the ? and ?* pentaquarks. (author)

  17. Modelling the widths of fission observables in GEF

    The General Fission code GEF calculates a variety of observables such as fission-fragment yields, prompt-fission neutrons and gammas. In this contribution we present a modified application of the statistical model that is used in GEF for estimating the widths of the mass distributions of the fission channels. The widths of the mass distributions of the different fission channels are traced back to the probability distributions of the corresponding quantum oscillators that are coupled to the heat bath, which is formed by the intrinsic degrees of freedom of the fissioning system under the influence of pairing correlations and shell effects. Following conclusion from stochastic calculations of Adeev and Pashkevich, an early freezing due to dynamical effects is assumed. It is shown that the mass width of the fission channels in low-energy fission is strongly influenced by the zero-point motion of the corresponding quantum oscillator. The observed variation of the mass widths of the asymmetric fission channels with excitation energy is attributed to the energy-dependent properties of the heat bath and not to the population of excited states of the corresponding quantum oscillator

  18. Improved determination of the width of the top quark

    Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Aoki, M.; Askew, A.; sman, B.; Atkins, S.; Atramentov, O.; Augsten, K.; Avila, C.; BackusMayes, J.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Belanger-Champagne, C.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besanon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Bose, T.; Brandt, A.; Brandt, O.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Brown, J.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burnett, T. H.; Buszello, C. P.; Calpas, B.; Camacho-Prez, E.; Carrasco-Lizarraga, M. A.; Casey, B. C. K.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Chevalier-Thry, S.; Cho, D. K.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Croc, A.; Cutts, D.; Das, A.; Davies, G.; de Jong, S. J.; De La Cruz-Burelo, E.; Dliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dorland, T.; Dubey, A.; Dudko, L. V.; Duggan, D.; Duperrin, A.; Dutt, S.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Facini, G.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garcia-Bellido, A.; Garca-Guerra, G. A.; Gavrilov, V.; Gay, P.; Geng, W.; Gerbaudo, D.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Golovanov, G.; Goussiou, A.; Graf, C. P.; Grannis, P. D.; Greder, S.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grnendahl, S.; Grnewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hagopian, S.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffr, M.; Jamin, D.; Jayasinghe, A.; Jesik, R.; Johns, K.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kaadze, K.; Kajfasz, E.; Karmanov, D.; Kasper, P. A.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kulikov, S.; Kumar, A.; Kupco, A.; Kur?a, T.; Kuzmin, V. A.; Lammers, S.; Landsberg, G.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lellouch, J.; Li, H.; Li, L.; Li, Q. Z.; Lietti, S. M.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; Lopes de Sa, R.; Lubatti, H. J.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Madar, R.; Magaa-Villalba, R.; Malik, S.; Malyshev, V. L.; Maravin, Y.; Martnez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Miconi, F.; Mondal, N. K.; Muanza, G. S.; Mulhearn, M.; Nagy, E.; Naimuddin, M.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Novaes, S. F.; Nunnemann, T.; Obrant, G.; Orduna, J.; Osman, N.; Osta, J.; Otero y Garzn, G. J.; Padilla, M.; Pal, A.; Parashar, N.; Parihar, V.; Park, S. K.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Ptroff, P.; Piegaia, R.; Pleier, M.-A.; Podesta-Lerma, P. L. M.; Podstavkov, V. M.; Polozov, P.; Popov, A. V.; Prewitt, M.; Price, D.; Prokopenko, N.; Qian, J.; Quadt, A.; Quinn, B.; Rangel, M. S.; Ranjan, K.; Ratoff, P. N.; Razumov, I.; Renkel, P.; Rijssenbeek, M.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Safronov, G.; Sajot, G.; Salcido, P.; Snchez-Hernndez, A.; Sanders, M. P.; Sanghi, B.; Santos, A. S.; Savage, G.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schliephake, T.; Schlobohm, S.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shchukin, A. A.; Shivpuri, R. K.; Simak, V.; Sirotenko, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Smith, K. J.; Snow, G. R.; Snow, J.; Snyder, S.; Sldner-Rembold, S.; Sonnenschein, L.

    2012-05-01

    We present an improved determination of the total width of the top quark, ?t, using 5.4fb-1 of integrated luminosity collected by the D0 Collaboration at the Tevatron pp Collider. The total width ?t is extracted from the partial decay width ?(t?Wb) and the branching fraction B(t?Wb). ?(t?Wb) is obtained from the t-channel single top-quark production cross section and B(t?Wb) is measured in tt events. For a top mass of 172.5 GeV, the resulting width is ?t=2.00-0.43+0.47GeV. This translates to a top-quark lifetime of ?t=(3.29-0.63+0.90)10-25s. We also extract an improved direct limit on the Cabibbo-Kobayashi-Maskawa quark-mixing matrix element 0.81<|Vtb|?1 at 95% C.L. and a limit of |Vtb'|<0.59 for a high-mass fourth-generation bottom quark assuming unitarity of the fourth-generation quark-mixing matrix.

  19. Improved determination of the width of the top quark

    Abazov V. M.; Abbott B.; Acharya B. S.; Adams M.; Adams T.; Alexeev G. D.; Alkhazov G.; Alton A.; Alverson G.; Aoki M.; Askew A.; Asman B.; Atkins S.; Atramentov O.; Augsten K.; Avila C.; BackusMayes J.; Badaud F.; Bagby L.; Baldin B.; Bandurin D. V.; Banerjee S.; Barberis E.; Baringer P.; Barreto J.; Bartlett J. F.; Bassler U.; Bazterra V.; Bean A.; Begalli M.; Belanger-Champagne C.; Bellantoni L.; Beri S. B.; Bernardi G.; Bernhard R.; Bertram I.; Besancon M.; Beuselinck R.; Bezzubov V. A.; Bhat P. C.; Bhatia S.; Bhatnagar V.; Blazey G.; Blessing S.; Bloom K.; Boehnlein A.; Boline D.; Boos E. E.; Borissov G.; Bose T.; Brandt A.; Brandt O.; Brock R.; Brooijmans G.; Bross A.; Brown D.; Brown J.; Bu X. B.; Buehler M.; Buescher V.; Bunichev V.; Burdin S.; Burnett T. H.; Buszello C. P.; Calpas B.; Camacho-Perez E.; Carrasco-Lizarraga M. A.; Casey C. K.; Castilla-Valdez H.; Chakrabarti S.; Chakraborty D.; Chan M.; Chandra A.; Chapon E.; Chen G.; Chevalier-Thery S.; Cho D. K.; Cho S. W.; Choi S.; Choudhary B.; Cihangir S.; Claes D.; Clutter J.; Cooke M.; Cooper W. E.; Corcoran M.; Couderc F.; Cousinou M. -C.; Croc A.; Cutts D.; Das A.; Davies G.; de Jong S. J.; De La Cruz-Burelo E.; Deliot F.; Demina R.; Denisov D.; Denisov S. P.; Desai S.; Deterre C.; DeVaughan K.; Diehl H. T.; Diesburg M.; Ding P. F.; Dominguez A.; Dorland T.; Dubey A.; Dudko L. V.; Duggan D.; Duperrin A.; Dutt S.; Dyshkant A.; Eads M.; Edmunds D.; Ellison J.; Elvira V. D.; Enari Y.; Evans H.; Evdokimov A.; Evdokimov V. N.; Facini G.; Ferbel T.; Fiedler F.; Filthaut F.; Fisher W.; Fisk H. E.; Fortner M.; Fox H.; Fuess S.; Garcia-Bellido A.; Garcia-Guerra G. A.; Gavrilov V.; Gay P.; Geng W.; Gerbaudo D.; Gerber C. E.; Gershtein Y.; Ginther G.; Golovanov G.; Goussiou A.; Graf C. P.; Grannis P. D.; Greder S.; Greenlee H.; Greenwood Z. D.; Gregores E. M.; Grenier G.; Gris Ph.; Grivaz J. -F.; Grohsjean A.; Gruenendahl S.; Gruenewald M. W.; Guillemin T.; Gutierrez G.; Gutierrez P.; Haas A.; Hagopian S.; Haley J.; Han L.; Harder K.; Harel A.; Hauptman J. M.; Hays J.; Head T.; Hebbeker T.; Hedin D.; Hegab H.; Heinson A. P.; Heintz U.; Hensel C.; La Cruz I. Heredia-De; Herner K.; Hesketh G.; Hildreth M. D.; Hirosky R.; Hoang T.; Hobbs J. D.; Hoeneisen B.; Hohlfeld M.; Hubacek Z.; Hynek V.; Iashvili I.; Ilchenko Y.; Illingworth R.; Ito A. S.; Jabeen S.; Jaffre M.; Jamin D.; Jayasinghe A.; Jesik R.; Johns K.; Johnson M.; Jonckheere A.; Jonsson P.; Joshi J.; Jung A. W.; Juste A.; Kaadze K.; Kajfasz E.; Karmanov D.; Kasper P. A.; Katsanos I.; Kehoe R.; Kermiche S.; Khalatyan N.; Khanov A.; Kharchilava A.; Kharzheev Y. N.; Kohli J. M.; Kozelov A. V.; Kraus J.; Kulikov S.; Kumar A.; Kupco A.; Kurca T.; Kuzmin V. A.; Lammers S.; Landsberg G.; Lebrun P.; Lee H. S.; Lee S. W.; Lee W. M.; Lellouch J.; Li H.; Li L.; Li Q. Z.; Lietti S. M.; Lim J. K.; Lincoln D.; Linnemann J.; Lipaev V. V.; Lipton R.; Liu Y.; Lobodenko A.; Lokajicek M.; de Sa R. Lopes; Lubatti H. J.; Luna-Garcia R.; Lyon A. L.; Maciel A. K. A.; Mackin D.; Madar R.; Magana-Villalba R.; Malik S.; Malyshev V. L.; Maravin Y.; Martinez-Ortega J.; McCarthy R.; McGivern C. L.; Meijer M. M.; Melnitchouk A.; Menezes D.; Mercadante P. G.; Merkin M.; et al.

    2012-05-04

    We present an improved determination of the total width of the top quark, {Gamma}{sub t}, using 5.4 fb{sup -1} of integrated luminosity collected by the D0 Collaboration at the Tevatron p{bar p} Collider. The total width {Gamma}{sub t} is extracted from the partial decay width {Gamma}(t {yields} Wb) and the branching fraction {Beta}(t {yields} Wb). {Gamma}(t {yields} Wb) is obtained from the t-channel single top-quark production cross section and {Beta}(t {yields} Wb) is measured in t{bar t} events. For a top mass of 172.5 GeV, the resulting width is {Gamma}{sub t} = 2.00{sub -0.43}{sup +0.47} GeV. This translates to a top-quark lifetime of {tau}{sub t} = (3.29{sub -0.63}{sup +0.90}) x 10{sup -25} s. We also extract an improved direct limit on the Cabibbo-Kobayashi-Maskawa quark-mixing matrix element 0.81 < |V{sub tb}| {le} 1 at 95% C.L. and a limit of |V{sub tb}| < 0.59 for a high-mass fourth-generation bottom quark assuming unitarity of the fourth-generation quark-mixing matrix.

  20. Spreading width of Gamow-Teller resonances in 208Bi

    The spreading width of the Gamow-Teller resonance in 208Bi is studied in the self-consistent TDA with the Skyrme interaction. Coupling between 1p1h states and 2p2h states are included in the TDA linear response function. (orig.)

  1. Sinusoidal and Space Vector Pulse Width Modulation for Inverter

    K. Mounika#1 , B. Kiran Babu

    2013-04-01

    Full Text Available Inverters inherently have the property of controlling output frequency but the output voltage cant be varied. Usually to vary output voltage we have to vary supply voltage which is not always possible for this reason PWM techniques gained momentum. Basic aim of PWM technique is to control output voltage and harmonic reduction. Pulse-width modulation (PWM, or pulseduration modulation (PDM, is a commonly used technique for controlling power to inertial electrical devices, made practical by modern electronic power switches. Here we apply PWM techniques like Sinusoidal pulse width modulation (SPWM and Space Vector Pulse width Modulation (SVPWM to inverter and study its performance. In Sinusoidal Pulse width modulation (SPWM we generate the gating signals by comparing a sinusoidal reference signal with a triangular carrier wave. In Space vector Modulation (SVPWM we consider a rotating phased which is obtained by adding all the three voltages. Modulation is accomplished by switching state of an inverter. Thus by comparing these two techniques we study the performance of our inverter.

  2. Harmonic orientation of pulse width modulation technique in multilevel inverters

    Urmila Bandaru; Subba D Rayudu

    2011-01-01

    The Multilevel Inverter topology gives the advantages of usage in high power and high voltage application with reduced harmonic distortion without a transformer. This paper presents a comparative study of orientation of higher ordered harmonics with increase in switching frequency around the frequency modulation index of nine level diode clamped inverter for different Switching frequency Multicarrier Pulse width Modulation.

  3. The Height + Width Rule in Children's Judgments of Quantity.

    Anderson, Norman H.; Cuneo, Diane O.

    1978-01-01

    In eight experiments, judgments of rectangle area by five-year-olds followed a reliable adding rule: height + width. In collateral work, the children judged the amount of liquid in a glass by a height-only rule. Implications for the Piagetian theories of centration and compensation are drawn. (SJL)

  4. Intrinsic propagation of magnetic island with finite width

    Full text: The modified Rutherford equation is used as a model equation which is describing temporal evolution of the neoclassical tearing mode (NTM). The often-used polarization term plays a stabilizing role on the NTM when the magnetic island rotates in the direction of the ion diamagnetic drift, therefore it is important to determine the direction of island propagation to estimate the threshold of island width for the NTM onset. The NTM is essentially the nonlinear instability, hence it is useful to perform numerical calculations for determining the propagation direction of island with finite width where nonlinearity becomes to be important. In this work, the dependence of island width on the direction of island propagation is investigated in two dimensional slab geometry by using a two-fluid model including both diamagnetic drifts of ions and electrons. When equilibrium current profile is unstable for the tearing mode, it is found that the magnetic island rotates toward the direction of the electron diamagnetic drift in so far as the island width is small comparable to the ion Larmor radius ρi. The threshold where the propagation direction turns into the direction of ion diamagnetic drift is found to large comparable to the island saturation width. We also found that the threshold becomes lower as the temperature ratio between ion and electron fluid becomes large or the poloidal beta becomes lower. The island is found to rotate toward the direction of the ion diamagnetic drift as the viscosity becomes small. The physical mechanism of determining the propagation direction is discussed in the presentation. (author)

  5. FREQUENCY DEPENDENCE OF PULSE WIDTH FOR 150 RADIO NORMAL PULSARS

    Chen, J. L. [Department of Physics and Electronic Engineering, Yuncheng University, 044000, Yuncheng, Shanxi (China); Wang, H. G., E-mail: hgwang.gz@gmail.com [Center for Astrophysics, Guangzhou University, 510006, Guangzhou (China)

    2014-11-01

    The frequency dependence of the pulse width is studied for 150 normal pulsars, mostly selected from the European Pulsar Network, for which the 10% multifrequency pulse widths can be well fit with the Thorsett relationship W {sub 10} = Aν{sup μ} + W {sub 10,} {sub min}. The relative fraction of pulse width change between 0.4 GHz and 4.85 GHz, η = (W {sub 4.85} – W {sub 0.4})/W {sub 0.4}, is calculated in terms of the best-fit relationship for each pulsar. It is found that 81 pulsars (54%) have η < –10% (group A), showing considerable profile narrowing at high frequencies, 40 pulsars (27%) have –10% ≤η ≤ 10% (group B), meaning a marginal change in pulse width, and 29 pulsars (19%) have η > 10% (group C), showing a remarkable profile broadening at high frequencies. The fractions of the group-A and group-C pulsars suggest that the profile narrowing phenomenon at high frequencies is more common than the profile broadening phenomenon, but a large fraction of the group-B and group-C pulsars (a total of 46%) is also revealed. The group-C pulsars, together with a portion of group-B pulsars with slight pulse broadening, can hardly be explained using the conventional radius-to-frequency mapping, which only applies to the profile narrowing phenomenon. Based on a recent version of the fan beam model, a type of broadband emission model, we propose that the diverse frequency dependence of pulse width is a consequence of different types of distribution of emission spectra across the emission region. The geometrical effect predicting a link between the emission beam shrinkage and spectrum steepening is tested but disfavored.

  6. FREQUENCY DEPENDENCE OF PULSE WIDTH FOR 150 RADIO NORMAL PULSARS

    The frequency dependence of the pulse width is studied for 150 normal pulsars, mostly selected from the European Pulsar Network, for which the 10% multifrequency pulse widths can be well fit with the Thorsett relationship W 10 = Aνμ + W 10, min. The relative fraction of pulse width change between 0.4 GHz and 4.85 GHz, η = (W 4.85 – W 0.4)/W 0.4, is calculated in terms of the best-fit relationship for each pulsar. It is found that 81 pulsars (54%) have η < –10% (group A), showing considerable profile narrowing at high frequencies, 40 pulsars (27%) have –10% ≤η ≤ 10% (group B), meaning a marginal change in pulse width, and 29 pulsars (19%) have η > 10% (group C), showing a remarkable profile broadening at high frequencies. The fractions of the group-A and group-C pulsars suggest that the profile narrowing phenomenon at high frequencies is more common than the profile broadening phenomenon, but a large fraction of the group-B and group-C pulsars (a total of 46%) is also revealed. The group-C pulsars, together with a portion of group-B pulsars with slight pulse broadening, can hardly be explained using the conventional radius-to-frequency mapping, which only applies to the profile narrowing phenomenon. Based on a recent version of the fan beam model, a type of broadband emission model, we propose that the diverse frequency dependence of pulse width is a consequence of different types of distribution of emission spectra across the emission region. The geometrical effect predicting a link between the emission beam shrinkage and spectrum steepening is tested but disfavored

  7. Conditions on Ramsey non-equivalence

    Axenovich, Maria; Rollin, Jonathan; Ueckerdt, Torsten

    2015-01-01

    Given a graph H, a graph G is called a Ramsey graph of H if there is a monochromatic copy of H in every coloring of the edges of G with two colors. Two graphs G, H are called Ramsey equivalent if they have the same set of Ramsey graphs. Fox et al. [J. Combin. Theory Ser. B 109 (2014), 120--133] asked whether there are two non-isomorphic connected graphs that are Ramsey equivalent. They proved that a clique is not Ramsey equivalent to any other connected graph. Results of Nesetril et al. showe...

  8. On the width of the full-critical region for thermal fluctuations around the superconducting transition in layered superconductors

    The crossover temperature between the mean-field and the full-critical regions for the thermal fluctuations around the superconducting transition is calculated for the first time in single-layered and bilayered (with two different distances and tunneling couplings between adjacent layers) superconductors at zero applied magnetic field. These results show, in particular, that the width of the full-critical region is somewhat smaller in layered superconductors than in equivalent bulk materials. These results are then discussed in connection with the superconducting transition of the high-Tc copper oxide superconductors. (orig.)

  9. On the width of the full-critical region for thermal fluctuations around the superconducting transition in layered superconductors

    Ramallo, M.V. [Univ. de Santiago de Compostela (Spain). Lab. de Bajas Temperaturas y Superconduct.; Vidal, F. [Univ. de Santiago de Compostela (Spain). Lab. de Bajas Temperaturas y Superconduct.

    1997-07-15

    The crossover temperature between the mean-field and the full-critical regions for the thermal fluctuations around the superconducting transition is calculated for the first time in single-layered and bilayered (with two different distances and tunneling couplings between adjacent layers) superconductors at zero applied magnetic field. These results show, in particular, that the width of the full-critical region is somewhat smaller in layered superconductors than in equivalent bulk materials. These results are then discussed in connection with the superconducting transition of the high-T{sub c} copper oxide superconductors. (orig.).

  10. Be Stars in the Open Cluster NGC 6830

    Yu, Po-Chieh; Lin, Hsing-Wen; Lee, Chien-De; Konidaris, Nick; Ngeow, Chow-Choong; Ip, Wing-Huen; Chen, Wen-Ping; Chen, Hui-Chen; Malkan, Matthew A; Chang, Chan-Kao; Laher, Russ; Huang, Li-Ching; Cheng, Yu-Chi; Edelson, Rick; Ritter, Andreas; Quimby, Robert; Ben-Ami, Sagi; Ofek, Eran O; Surace, Jason; Kulkarni, Shrinivas R

    2016-01-01

    We report the discovery of 2 new Be stars, and re-identify one known Be star in the open cluster NGC 6830. Eleven H-alpha emitters were discovered using the H-alpha imaging photometry of the Palomar Transient Factory Survey. Stellar membership of the candidates was verified with photometric and kinematic information using 2MASS data and proper motions. The spectroscopic confirmation was carried out by using the Shane 3-m telescope at Lick observatory. Based on their spectral types, three H-alpha emitters were confirmed as Be stars with H-alpha equivalent widths > -10 Angstrom. Two objects were also observed by the new spectrograph SED-Machine on the Palomar 60 inch Telescope. The SED-Machine results show strong H-alpha emission lines, which are consistent with the results of the Lick observations. The high efficiency of the SED-Machine can provide rapid observations for Be stars in a comprehensive survey in the future.

  11. The principle of equivalence at finite temperature

    It is demonstrated that the equivalence principle is violated by radiative corrections to the gravitational and inertial masses at finite temperature. It is argued that this result can be attributed to the Lorentz noninvariance of the finite temperature vacuum. (author)

  12. Equivalence relations and the reinforcement contingency.

    Sidman, M

    2000-07-01

    Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second-order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that participate in the contingency. This conception of the origin of equivalence relations leads to a number of new and verifiable ways of conceptualizing equivalence relations and, more generally, the stimulus control of operant behavior. The theory is also capable of experimental disproof. PMID:10966100

  13. Quantum equivalence principle without mass superselection

    Hernandez-Coronado, H., E-mail: hcoronado@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Av. Universidad, Del. Coyoacán, México (Mexico); Okon, E., E-mail: eokon@filosoficas.unam.mx [Instituto de Investigaciones Filosóficas, Universidad Nacional Autónoma de México, Av. Universidad, Del. Coyoacán, México (Mexico)

    2013-11-08

    The standard argument for the validity of Einstein's equivalence principle in a non-relativistic quantum context involves the application of a mass superselection rule. The objective of this work is to show that, contrary to widespread opinion, the compatibility between the equivalence principle and quantum mechanics does not depend on the introduction of such a restriction. For this purpose, we develop a formalism based on the extended Galileo group, which allows for a consistent handling of superpositions of different masses, and show that, within such scheme, mass superpositions behave as they should in order to obey the equivalence principle. - Highlights: • We propose a formalism for consistently handling, within a non-relativistic quantum context, superpositions of states with different masses. • The formalism utilizes the extended Galileo group, in which mass is a generator. • The proposed formalism allows for the equivalence principle to be satisfied without the need of imposing a mass superselection rule.

  14. ICD-10 Oregon-Specific Equivalence Map

    U.S. Department of Health & Human Services — DISCLAIMER: The Oregon-Specific Equivalence Map includes ICD-9 codes translated to ICD-10 based on a clinical and policy analysis of each code. It is not intended...

  15. Equivalence Principle, Higgs Boson and Cosmology

    Mauro Francaviglia

    2013-05-01

    Full Text Available We discuss here possible tests for Palatini f(R-theories together with their implications for different formulations of the Equivalence Principle. We shall show that Palatini f(R-theories obey the Weak Equivalence Principle and violate the Strong Equivalence Principle. The violations of the Strong Equivalence Principle vanish in vacuum (and purely electromagnetic solutions as well as on short time scales with respect to the age of the universe. However, we suggest that a framework based on Palatini f(R-theories is more general than standard General Relativity (GR and it sheds light on the interpretation of data and results in a way which is more model independent than standard GR itself.

  16. On the off-diagonal operator equivalents

    A closed polynomial formula for the qth component of any off-diagonal operator equivalent of order k (integer or half-integer) is derived in terms of two-dimensional harmonic oscillator creation and annihilation operators. (Auth.)

  17. Dosimetry with tissue equivalent plastic ionization chamber

    Tissue equivalent plastics have been widely used as the materials for radiation detectors and phantoms, and their muscle equivalency is reasonable for the radiation beam for radiotherapy. As the kerma factor for light elements is not known well above 30 MeV, it is desirable to make a tissue equivalent plastic, in which oxygen content is improved rather than that in present tissue equivalent plastics. One of the difficulties in the standardization of neutron dosimetry arised from that the different dosimetric constants have been used at respective institutions, and this is clear from the results of intercomparison of some neutron doses. The pair chamber method is valid for mixed fields, bacause neutron and ?-ray doses can be measured separately. However, the saturation characteristic of carbon chambers is very poor, therefore the correction factor must be determined experimentally for each individual ionization chamber. (Kobatake, H.)

  18. Nuclear Regulatory Commission equivalency evaluation report

    This paper provides the basis for concluding that using the seismic design criteria, defined in DOE order 4580.28, Natural Phenomena Hazards Mitigation, and its implementing standards provides safety equivalent to NRC criteria

  19. [Therapeutic equivalence of the new oral anticoagulants].

    Moreno Villar, A; Nacle López, I; Barbero Hernández, M J; Lizan Tudela, L

    2015-10-01

    In an attempt to minimize the economic impact due to the incorporation of innovative drugs, health authorities have promoted and supported the evaluation and market positioning of drugs, as equivalent therapeutic alternatives. This issue has recently gained importance, possibly due to the current economic crisis. The equivalent therapeutic alternatives are justified by the need to compete on price, and by the authorities recommendation to establish therapeutic equivalence, price and financing of medicinal products at the same time. The establishment of the new oral anticoagulants and the equivalent therapeutic alternatives is a problematic issue if it is based on the absence of direct comparisons between different drugs and the questionable methodology used in the current indirect comparisons. Currently, it is difficult to determine when a new oral anticoagulant is more recommendable than others, but efforts are being made in order to propose alternatives for the decision based on patient characteristics. PMID:26146035

  20. Agency Full Time Equivalency Reporting System

    US Agency for International Development — AFTERS provides an automated means for the Agency to report its full time equivalency work years to the Office of Management and Budget (OMB) and Office of...

  1. The equivalent fundamental-mode source

    In 1960, Hansen analyzed the problem of assembling fissionable material in the presence of a weak neutron source. Using point kinetics, he defined the weak source condition and analyzed the consequences of delayed initiation during ramp reactivity additions. Although not clearly stated in Hansen's work, the neutron source strength that appears in the weak source condition corresponds to the equivalent fundamental-mode source. In this work, we describe the concept of an equivalent fundamental-mode source and we derive a deterministic expression for a factor, g*, that converts any arbitrary source distribution to an equivalent fundamental-mode source. We also demonstrate a simplified method for calculating g* in subcritical systems. And finally, we present a new experimental method that can be employed to measure the equivalent fundamental-mode source strength in a multiplying assembly. We demonstrate the method on the zero-power, XIX-1 assembly at the Fast Critical Assembly (FCA) Facility, Japan Atomic Energy Research Institute (JAERI)

  2. Dose equivalent index for fast electrons

    Monte Carlo calculations of the deep and shallow dose equivalent index produced by electron beams in the energy region 5-22 MeV have been performed for unidirectional, opposing, rotating and isotropic irradiations of the spherical tissue equivalent phantom. The observed dose maxima are attributed to multiple scattering and range effects and occur in the outer 10 mm shell. The isotropy factor varies from 2.48 at 5 MeV to 1.89 at 22 MeV. The signal of a detector with isotropic response and wall thickness 0.5 g/cm2 is shown to be a suitable measure of dose equivalent index for fast electrons. The average dose equivalent in the spherical phantom is discussed as an alternative concept. (author)

  3. The first spectra for the RX J0440.9+4431 from 2m Terskol telescope

    Simon, Andrew; Bondar, A. V.; Reshetnyk, V. M.

    2012-01-01

    We present the first results on the spectra of Be/X-ray binary RX J0440.9+4431 obtained with the 2m Ritchey-Cretein-Coude telescope with Cassegrain Multi Mode Spectrograph (CMMS) (with R = 14000) at Terskol observatory. The H-alpha line profile indicates that the new episode of the V/R variability is occuring in the system. The profiles of the H-alpha, H-beta and HeI 7065.71, 6678.15, 5875.97 lines were analyzed and equivalent width were determined. We compared our H-alpha line profile parame...

  4. Equivalent Scale on Food Consumption in Turkey

    Haydar Sengul

    2006-01-01

    This study investigates effect of household composition and size on food consumption in the rural and urban areas of Turkey through equivalence scales that vary by household member age. Food consumption studies on Turkey have tended to ignore the impact of household composition in consumption traditionally analyses of food consumption are conducted on a per capita basis. Equivalence scales were estimated by Engel method using Household Consumption Expenditure Survey (HCES) data of the State I...

  5. The equivalence principle and spatial curvature

    An examination is made of the connection between the equivalence principle of general relativity and the non-Euclidean properties of space. The arguments commonly advanced to suggest a necessary connection between these two features of general relativity are reviewed and critically discussed. It is shown that although gravitational time dilation is an immediate consequence of the equivalence principle the corresponding effects on space are not such immediate or logically necessary consequences of this principle. (author)

  6. The endotopism semigroups of an equivalence relation

    Zhuchok, Yu V [National Taras Shevchenko University of Kiev (Ukraine); Toichkina, E A [Lugansk Taras Shevchenko National University, Lugansk (Ukraine)

    2014-05-31

    In this work we investigate six types of endotopism semigroups for a given equivalence relation. Necessary and sufficient conditions for the existence of all such endotopisms are presented. Conditions for the regularity and coregularity of each of the endotopism semigroups of agiven type are established. The notion of the endotype of abinary relation with respect to its endotopisms is introduced and the endotype of an arbitrary equivalence relation is calculated. Bibliography: 26 titles.

  7. Equivalence relations and the reinforcement contingency.

    Sidman, M

    2000-01-01

    Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second-order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that...

  8. Robust stochastic control and equivalent martingale measures

    ØKSENDAL, BERNT; Sulem, Agnès

    2011-01-01

    We study a class of robust, or worst case scenario, optimal control problems for jump diffusions. The scenario is represented by a probability measure equivalent to the initial probability law. We show that if there exists a control that annihilates the noise coefficients in the state equation and a scenario which is an equivalent martingale measure for a specific process which is related to the control-derivative of the state process, then this control and this probability measure are optima...

  9. Quantitative and methodological aspects of stimulus equivalence

    O'Mara, Henry

    1991-01-01

    The number of different ways of linking stimuli in the training phase of a conditional discrimination procedure designed to teach equivalence relations has hitherto been underestimated. An algorithm from graph theory that produces the correct number of such different ways is given. The establishment of equivalence relations requires transitive stimulus control. A misconception in a previous analysis of the conditions necessary for demonstrating transitive stimulus control is indicated. This m...

  10. Dark matter and the equivalence principle

    Frieman, Joshua A.; Gradwohl, Ben-Ami

    1993-01-01

    A survey is presented of the current understanding of dark matter invoked by astrophysical theory and cosmology. Einstein's equivalence principle asserts that local measurements cannot distinguish a system at rest in a gravitational field from one that is in uniform acceleration in empty space. Recent test-methods for the equivalence principle are presently discussed as bases for testing of dark matter scenarios involving the long-range forces between either baryonic or nonbaryonic dark matter and ordinary matter.

  11. Personnel monitors utilizing tissue equivalent proportional counters

    The U.S. Department of Energy has established a program to improve neutron dosimetry at facilities where a significant number of workers are exposed to fast neutrons from handling isotopic neutron sources. One facet of this program is the development of small, lightweight personnel monitors to determine dose equivalent as the workers are exposed. These instruments use small cylindrical tissue equivalent proportional counters to detect neutrons, and a microprocessor to determine absorbed dose and dose equivalent. A Pocket REM Meter containing three cylindrical tissue equivalent proportional counters 1.9-cm in diameter and 13-cm long is developed. The instrument utilizes hybrid circuitry and a 256 channel analog to digital converter to supply signals to a CMOS microprocessor, which calculates absorbed dose and dose equivalent for neutrons and displays the results on a liquid crystal display. Independent measurements at the Pacific Northwest Laboratory verified that the Pocket REM Meter is accurate within 20% for determining neutron dose equivalent when exposed to unmoderated or slightly moderated Cf-252 sources, which have been calibrated by the U.S. National Bureau of Standards. The Laboratory is developing a Total Dose Meter to measure absorbed dose and determine dose equivalent from mixed radiation fields of neutrons and gamma rays. Using a single tissue equivalent proportional counter with two amplifiers operated at different gains. Using empirical algorithms derived from exposures to monoenergetic neutrons, it is possible to determine quality factors within about 7% for neutrons with energies between 200 KeV and 7.5 MeV

  12. Income Dependent Equivalence Scales, Inequality, and Poverty

    Dudel, Christian; Garbuszus, Jan Marvin; Ott, Notburga; Werding, Martin

    2015-01-01

    Most equivalence scales which are applied in research on poverty and inequality do not depend on income, although there is strong empirical evidence that equivalence scales in fact are income dependent. This paper explores the consistency of results derived from income independent and income dependent scales. It is shown that scales of both types inevitably lead to differing assessments of poverty and inequality under quite general conditions. German microdata will be used to demonstrate and ...

  13. S-equivalents lagrangians in generalized mechanics

    The problem of s-equivalent lagrangians is considered in the realm of generalized mechanics. Some results corresponding to the ordinary (non-generalized) mechanics are extended to the generalized case. A theorem for the reduction of the higher order lagrangian description to the usual order is found to be useful for the analysis of generalized mechanical systems and leads to a new class of equivalence between lagrangian functions. Some new perspectives are pointed out. (Author)

  14. Algebraic method for finding equivalence groups

    Bihlo, Alexander; Cardoso-Bihlo, Elsa Dos Santos; Popovych, Roman O.

    2015-01-01

    The algebraic method for computing the complete point symmetry group of a system of differential equations is extended to finding the complete equivalence group of a class of such systems. The extended method uses the knowledge of the corresponding equivalence algebra. Two versions of the method are presented, where the first involves the automorphism group of this algebra and the second is based on a list of its megaideals. We illustrate the megaideal-based version of the method with the com...

  15. On the generation of equivalent hamiltonians

    A new approach to the equivalence problem (in phase space) is presented. Given a Hamiltonian describing a system of particles with two degrees of freedom (and the corresponding Hamilton-Jacobi equation), it is shown how to find the most general family of Hamiltonian functions that generates new Hamilton-Jacobi equation with the following (and essential) characteristic, here defined as equivalence: every new solution is also a solution of the original Hamilton-Jacobi equation and vice-versa. (Author)

  16. Determination of total and partial widths of unbound states

    Observations of the ?-ray decay between unbound states and the subsequent decay of the lower state have enabled the determination of the relative proton and ?-radiation widths of the lower state. These measurements together with a determination of the resonance strength of the lower state make it possible, in some cases, to deduce the total and all partial decay widths of this state. These measurements are clearly restricted in application to nuclei with low lying states which are unbound against proton decay. Nevertheless there are several nuclei in particular those with 2n neutrons and 2n+1 protons for which useful information can be extracted by this method. Applications of this method to states in the nuclei 59Cu, 41Sc and 29P are discussed

  17. Finite pion width effects on the rho-meson

    We study the influence of the finite damping width of pions on the in-medium properties of the ρ-meson in an interacting meson-gas model at finite temperature. Using vector dominance also implications on the resulting dilepton spectra from the decay of the ρ-meson are presented. A set of coupled Dyson equations with self-energies up to the sunset diagram level is solved self-consistently. Following a PHI-derivable scheme the self-energies are dynamically determined by the self-consistent propagators. Some problems concerning the self-consistent treatment of vector or gauge bosons on the propagator level, in particular, if coupled to currents arising from particles with a sizable damping width, are discussed

  18. Finite pion width effects on the $\\rho$-meson

    Van Hees, H; Knoll, Joern

    2000-01-01

    We study the influence of the finite damping width of pions on the in-medium properties of the rho-meson in an interacting meson gas model at finite temperature. Using vector dominance also implications on the resulting dilepton spectra from the decay of the rho-meson are presented. A set of coupled Dyson equations with self energies up to the sunset diagram level is solved self consistently. Following a Phi-derivable scheme the self energies are dynamically determined by the self consistent propagators. Some problems concerning the self consistent treatment of vector or gauge bosons on the propagator level, in particular, if coupled to currents arising from particles with a sizable damping width, are discussed.

  19. The SOL width and the MHD interchange instability in tokamaks

    Instabilities in the SOL plasma can strongly influence the SOL plasma behaviour and in particular the SOL width. The SOL stability analysis shows that there exists a critical ratio of the thermal energy and the magnetic energy. If the SOL beta is greater than this critical value, the magnetic field cannot prevent the plasma displacement and a strong MHD instability in the SOL occurs. In the opposite case only slower resistive instabilities can develop. A theoretical investigation of the SOL plasma stability is presented for JET single-null and double-null divertor configurations. The dependence of the stability threshold on the SOL beta and on the sheath resistance is established. Applying a simple mixing length argument gives the scaling of the SOL width. 5 refs., 2 figs

  20. The SOL width and the MHD interchange instability in tokamaks

    Kerner, W. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Pogutse, O. [Kurchatov institute, Moscow (Russian Federation)

    1994-07-01

    Instabilities in the SOL plasma can strongly influence the SOL plasma behaviour and in particular the SOL width. The SOL stability analysis shows that there exists a critical ratio of the thermal energy and the magnetic energy. If the SOL beta is greater than this critical value, the magnetic field cannot prevent the plasma displacement and a strong MHD instability in the SOL occurs. In the opposite case only slower resistive instabilities can develop. A theoretical investigation of the SOL plasma stability is presented for JET single-null and double-null divertor configurations. The dependence of the stability threshold on the SOL beta and on the sheath resistance is established. Applying a simple mixing length argument gives the scaling of the SOL width. 5 refs., 2 figs.

  1. Stark widths and oscillator strengths of Xe III lines

    In order to test the reliability of the configuration interaction (CI) method to predict the atomic parameters viz oscillator strengths of complex ions, we measured the profiles of forty (40) strong 6s-6p transitions of Xe III emitted by a pulsed capillary discharge. After deconvoluting the experimental shapes, Stark widths and relative oscillator strengths were obtained. When least square fitted (LSF) parameters were used in addition to extensive CI (CI + LSF), the agreement between theory and experiment for the gf's is within a factor two for the whole of the lines. Concerning the widths, the semiempirical approach provides values also within a factor two when the Gaunt factor is taken to be g(x) ? 0.30. (orig.)

  2. The complexity of the fermionant, and immanants of constant width

    Mertens, Stephan

    2011-01-01

    In the context of statistical physics, Chandrasekharan and Wiese recently introduced the \\emph{fermionant} $\\Ferm_k$, a determinant-like quantity where each permutation $\\pi$ is weighted by $-k$ raised to the number of cycles in $\\pi$. We show that computing $\\Ferm_k$ is #P-hard under Turing reductions for any constant $k > 2$, and is $\\oplusP$-hard for $k=2$, even for the adjacency matrices of planar graphs. As a consequence, unless the polynomial hierarchy collapses, it is impossible to compute the immanant $\\Imm_\\lambda \\,A$ as a function of the Young diagram $\\lambda$ in polynomial time, even if the width of $\\lambda$ is restricted to be at most 2. In particular, if $\\Ferm_2$ is in P, or if $\\Imm_\\lambda$ is in P for all $\\lambda$ of width 2, then $\\NP \\subseteq \\RP$ and there are randomized polynomial-time algorithms for NP-complete problems.

  3. Statistical analysis of P-wave neutron reduced widths

    The fluctuations of the p-wave neutron reduced widths for fifty one nuclei have been analyzed with emphasis on recent measurements by a statistical procedure which is based on the method of maximum likelihood. It is shown that the p-wave neutron reduced widths of even-even nuclei fallow single channel Porter Thomas distribution (χ2-distribution with degree of freedom ν=1) for most of the cases where there are no intermediate structure. It is emphasized that the distribution in nuclei other than even-even may differ from a χ2-distribution with one degree of freedom. Possible explanation and significance of this deviation from ν=1 is given. (author)

  4. Determination of the width of the top quark

    Abazov, V M; Abolins, M; Acharya, B S; Adams, M; Adams, T; Alexeev, G D; Alkhazov, G; Altona, A; Alverson, G; Alves, G A; Ancu, L S; Aoki, M; Arnoud, Y; Arov, M; Askew, A; \\degAsman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bazterra, V; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besan?con, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brandt, O; Brock, R; Brooijmans, G; Bross, A; Brown, D; Brown, J; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdinb, S; Burnett, T H; Buszello, C P; Calpas, B; Camacho-P?erez, E; Carrasco-Lizarraga, M A; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chen, G; Chevalier-Th?ery, S; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M -C; Croc, A; Cutts, D; ?Cwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; D?eliot, F; Demarteau, M; Demina, 47 R; Denisov, D; Denisov, S P; Desai, S; DeVaughan, K; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerbaudo, D; Gerber, C E; Gershtein, Y; Ginther, G; Golovanov, G; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J -F; Grohsjean, A; Gr?unendahl, S; Gr?unewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haasc, A; Hagopian, S; Haley, J; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Head, T; Hebbeker, T; Hedin, D; Hegab, H; Heinson, A P; Heintz, U; Hensel, C; La Cruz, I Heredia-De; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffr?e, M; Jain, S; Jamin, D; Jesik, R; Johns, K; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Joshi, J; Justed, A; Kaadze, K; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kohli, J M; Kozelov, A V; Kraus, J; Kumar, A; Kupco, A; Kur?ca, T; Kuzmin, V A; Kvita, J; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, S W; Lee, W M; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garciae, R; Lyon, A L; Maciel, A K A; Mackin, D; Madar, R; Maga?na-Villalba, R; Malik, S; Malyshev, V L; Maravin, Y; Mart?\\inez-Ortega, J; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Muanza, G S; Mulhearn, M; Nagy, E; Naimuddin, M; Narain, M; Nayyar, R; Neal, H A; Negret, J P; Neustroev, P; Novaes, S F; Nunnemann, T; Obrant, G; Orduna, J; Osman, N; Osta, J; Garz?on, G J Otero y; Owen, 1 M; Padilla, M; Pangilinan, M; Parashar, N; Parihar, V; Park, S K; Parsons, J; Partridgec, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Petrillo, G; P?etroff, P; Piegaia, R; Piper, J; Pleier, M -A; Podesta-Lermaf, P L M; Podstavkov, V M; Pol, M -E; Polozov, P; Popov, A V; Prewitt, M; Price, D; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Ranjan, K; Ratoff, P N; Razumov, I; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; S?anchez-Hern?andez, A; Sanders, M P; Sanghi, B; Santos, A S; Savage, G; Sawyer, L; Scanlon, T; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shary, V; Shchukin, A A; Shivpuri, R K; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Smith, K J; Snow, G R; Snow, J; Snyder, S; S?oldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strauss, E; Strauss, M; Strom, D; Stutte, L; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Titov, M; Tokmenin, V V; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Uvarov, L; Uzunyan, S Uvarov S; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S; Verzocchi, M; Vesterinen, M; Vilanova, D; Vint, P; Vokac, P; Wahl, H D; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weberg, M; Welty-Rieger, L; Wetstein, M; White, A; Williams, D Wicke M R J; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Xu, C; Yacoob, S; Yamada, R; Yang, W -C; Yasuda, T; Yatsunenko, Y A; Ye, Z; Yin, H; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zelitch, S; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zivkovic, L

    2010-01-01

    We extract the total width of the top quark, Gamma_t, from the partial decay width Gamma(t -> W b) measured using the t-channel cross section for single top quark production and from the branching fraction B(t -> W b) measured in ttbar events using up to 2.3 fb^-1 of integrated luminosity collected by the D0 Collaboration at the Tevatron ppbar Collider. The result is Gamma_t = 1.99 +0.69 -0.55 GeV, which translates to a top-quark lifetime of tau_t = (3.3 +1.3 -0.9) x 10^-25 s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |Vtb'| < 0.63 at 95% C.L.

  5. The excision width in surgical treatment of basal cell carcinoma

    Mališ M.

    2006-01-01

    Full Text Available Basal cell carcinoma originates from pluripotent cells of basal layer of epiderm, external covering of hair follicles, sebaceous glands or other skin adnexa. It is characterized by local infiltrating and sometimes destructive growth. There are several types of basal cell carcinomas that may be manifested in over 12 clinical forms. Surgical treatment depends to a large extent on the histological type, localization and its clinical manifestation. The analysis included 250 patients of both gender and different age, operated for basal cell carcinoma. Clinical characteristics of basal cell carcinoma and the width of the excision were described. It was concluded that the width of the excision of basal cell cancer was in relation to histological type. .

  6. Determination of the width of the top quark.

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Aoki, M; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bazterra, V; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brandt, O; Brock, R; Brooijmans, G; Bross, A; Brown, D; Brown, J; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calpas, B; Camacho-Pérez, E; Carrasco-Lizarraga, M A; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chen, G; Chevalier-Théry, S; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Croc, A; Cutts, D; Ćwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De la Cruz-Burelo, E; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; DeVaughan, K; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerbaudo, D; Gerber, C E; Gershtein, Y; Ginther, G; Golovanov, G; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hagopian, S; Haley, J; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Head, T; Hebbeker, T; Hedin, D; Hegab, H; Heinson, A P; Heintz, U; Hensel, C; Heredia-De la Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jamin, D; Jesik, R; Johns, K; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Joshi, J; Juste, A; Kaadze, K; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kohli, J M; Kozelov, A V; Kraus, J; Kumar, A; Kupco, A; Kurča, T; Kuzmin, V A; Kvita, J; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, S W; Lee, W M; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Madar, R; Magaña-Villalba, R; Malik, S; Malyshev, V L; Maravin, Y; Martínez-Ortega, J; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Muanza, G S; Mulhearn, M; Nagy, E; Naimuddin, M; Narain, M; Nayyar, R; Neal, H A; Negret, J P; Neustroev, P; Novaes, S F; Nunnemann, T; Obrant, G; Orduna, J; Osman, N; Osta, J; Otero y Garzón, G J; Owen, M; Padilla, M; Pangilinan, M; Parashar, N; Parihar, V; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Petrillo, G; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pol, M-E; Polozov, P; Popov, A V; Prewitt, M; Price, D; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Ranjan, K; Ratoff, P N; Razumov, I; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Santos, A S; Savage, G; Sawyer, L; Scanlon, T; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shary, V; Shchukin, A A; Shivpuri, R K; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Smith, K J; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strauss, E; Strauss, M; Strom, D; Stutte, L; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Titov, M; Tokmenin, V V; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Uvarov, L; Uvarov, S; Uzunyan, S; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S; Verzocchi, M; Vesterinen, M; Vilanova, D; Vint, P; Vokac, P; Wahl, H D; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, M; Welty-Rieger, L; Wetstein, M; White, A; Wicke, D; Williams, M R J; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Xu, C; Yacoob, S; Yamada, R; Yang, W-C; Yasuda, T; Yatsunenko, Y A; Ye, Z; Yin, H; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zelitch, S; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zivkovic, L

    2011-01-14

    We extract the total width of the top quark, Γ(t), from the partial decay width Γ(t → Wb) measured using the t-channel cross section for single top-quark production and from the branching fraction B(t → Wb) measured in tt events using up to 2.3  fb(-1) of integrated luminosity collected by the D0 Collaboration at the Tevatron pp Collider. The result is Γ(t) = 1.99(-0.55)(+0.69)  GeV, which translates to a top-quark lifetime of τ(t) = (3.3(-0.9)(+1.3)) × 10(-25)   s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |V(tb')| < 0.63 at 95% C.L. PMID:21405220

  7. The Definition of Mass and Width of Relativistic Resonances

    For relativistic resonances, the lineshape alone does not uniquely determine the resonance parameters, namely the mass (M) and width (?). A unique definition of the resonance parameters is given if one uses a broader theory of quasistable particles, i.e. which unifies resonances and decaying states. The theory of quasistable particles is developed in analogy to that of stable particles: Wigner's Unitary Irreducible representations of the Poincare group characterize stable particles by mass (M) and spin (j), whereas quasistable particles will be characterized by mass squared sR = (MR - i?R/2) and spin (j). It follows that the resonance width ?R is related to the lifetime of the state by ?R = 1/?. The Z-boson is used as an example

  8. Mass spectra and leptonic decay widths of heavy quarkonia

    Motyka, L; Motyka, Leszek; Zalewski, Kacper

    1998-01-01

    A nonrelativistic Hamiltonian with plausible spin dependent corrections is proposed for the quarkonia below their respective strong decay thresholds. With only six free parameters this model reproduces the nine known masses of the bottomonia within about 1 MeV, the six known masses of the charmonia within a few MeV and the five known leptonic decay widths of the ${}^3S_1$ states within about \\mbox{20 \\%}. The model is then used to predict the masses of the remaining 43 quarkonia (some of them for the first time) and of the leptonic decay widths of the two ${}^1S_0(\\overline{b}c)$ states. Comparison with some other models is made.

  9. A Direct Measurement of the $W$ Decay Width

    Vine, Troy; /University Coll. London

    2008-08-01

    A direct measurement of the W boson total decay width is presented in proton-antiproton collisions at {radical}s = 1.96 TeV using data collected by the CDF II detector. The measurement is made by fitting a simulated signal to the tail of the transverse mass distribution in the electron and muon decay channels. An integrated luminosity of 350 pb{sup -1} is used, collected between February 2002 and August 2004. Combining the results from the separate decay channels gives the decay width as 2.038 {+-} 0.072 GeV in agreement with the theoretical prediction of 2.093 {+-} 0.002 GeV. A system is presented for the management of detector calibrations using a relational database schema. A description of the implementation and monitoring of a procedure to provide general users with a simple interface to the complete set of calibrations is also given.

  10. Conjugacy Growth and Conjugacy Width of Certain Branch Groups

    Fink, Elisabeth

    2014-01-01

    The conjugacy growth function counts the number of distinct conjugacy classes in a ball of radius $n$. We give a lower bound for the conjugacy growth of certain branch groups, among them the Grigorchuk group. This bound is a function of intermediate growth. We further proof that certain branch groups have the property that every element can be expressed as a product of uniformly boundedly many conjugates of the generators. We call this property bounded conjugacy width. We also show how bounde...

  11. Characterizing the width of amphibian movements during postbreeding migration.

    Coster, Stephanie S; Veysey Powell, Jessica S; Babbitt, Kimberly J

    2014-06-01

    Habitat linkages can help maintain connectivity of animal populations in developed landscapes. However, the lack of empirical data on the width of lateral movements (i.e., the zigzagging of individuals as they move from one point to point another) makes determining the width of such linkages challenging. We used radiotracking data from wood frogs (Lithobates sylvaticus) and spotted salamanders (Ambystoma maculatum) in a managed forest in Maine (U.S.A.) to characterize movement patterns of populations and thus inform planning for the width of wildlife corridors. For each individual, we calculated the polar coordinates of all locations, estimated the vector sum of the polar coordinates, and measured the distance from each location to the vector sum. By fitting a Gaussian distribution over a histogram of these distances, we created a population-level probability density function and estimated the 50th and 95th percentiles to determine the width of lateral movement as individuals progressed from the pond to upland habitat. For spotted salamanders 50% of lateral movements were ≤13 m wide and 95% of movements were ≤39 m wide. For wood frogs, 50% of lateral movements were ≤17 m wide and 95% of movements were ≤ 51 m wide. For both species, those individuals that traveled the farthest from the pond also displayed the greatest lateral movement. Our results serve as a foundation for spatially explicit conservation planning for pond-breeding amphibians in areas undergoing development. Our technique can also be applied to movement data from other taxa to aid in designing habitat linkages. PMID:24423254

  12. D* width and the study of F and F*

    Recent results on the D*, F, and F* production in e+e- from HRS and MARK III are summarized. An improved upper limit on the decay width of D* is reported. A brief review of the characteristics of F and the updated data of the F production in e+e- are given. A new measurement on F* is made using the associated production method in the reaction e+e- → FF*

  13. Widths of Isobaric Analog Resonances: a microscopic approach

    G. Colo'; Sagawa, H.; N. Van Giai(Institut de Physique Nucleaire, Orsay, France); Bortignon, P. F.; Suzuki, T.

    1998-01-01

    A self-consistent particle-phonon coupling model is used to investigate the properties of the isobaric analog resonance in $^{208}$Bi. It is shown that quantitative agreement with experimental data for the energy and the width can be obtained if the effects of isospin-breaking nuclear forces are included, in addition to the Coulomb force effects. A connection between microscopic model predictions and doorway state approaches which make use of the isovector monopole resonance, is established v...

  14. Pulse-Width-Modulating Driver for Brushless dc Motor

    Salomon, Phil M.

    1991-01-01

    High-current pulse-width-modulating driver for brushless dc motor features optical coupling of timing signals from low-current control circuitry to high-current motor-driving circuitry. Provides high electrical isolation of motor-power supply, helping to prevent fast, high-current motor-driving pulses from being coupled through power supplies into control circuitry, where they interfere with low-current control signals.

  15. Some Statistical Properties of Partial Radiation Widths in Tungsten

    High-resolution gamma-ray specta from six resonances in 182W, three resonances in 184W and five resonances in 186W have been obtained. By using the method of maximum likelihood, the properties of the reduced widths have been compared with those expected from a random distribution. There is no convincing discrepancy between the data and that expected from a random distribution. (author)

  16. Total Width of 125 GeV Higgs Boson

    Barger, Vernon; Ishida, Muneyuki; Keung, Wai-Yee

    2012-01-01

    By using the LHC and Tevatron measurements of the cross sections to various decay channels relative to the standard model Higgs boson, the total width of the putative 125 GeV Higgs boson is determined as 6.1 +7.7-2.9 MeV. We describe a way to estimate the branching fraction for Higgs decay to dark matter. We also discuss a No-Go theorem for the gammagamma signal of the Higgs boson at the LHC.

  17. Porous Alumina Films with Width-Controllable Alumina Stripes

    Huang Shi-Ming

    2010-01-01

    Full Text Available Abstract Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

  18. Soft-switching techniques for pulse-width-modulated converters

    Hua, Guichao

    1994-01-01

    The concept of soft-switching pulse-width-modulated (PWM) technique was proposed aimed at combining the advantages of both the conventional PWM technique and the resonant technique. This work presents four new families of soft-switching PWM converters: the zero-voltage-switched (ZVS) PWM converters, the zero-current-switched (ZCS) PWM converters, the zerovoltage- transition (ZVT) PWM converters, and the zero-current-transition (ZCT) PWM converters. The family of ZVS- and ...

  19. Influence of pulse width and detuning on coherent phonon generation

    Kazutaka G. Nakamura; Shikano, Yutaka; Kayanuma, Yosuke

    2015-01-01

    We investigated the coherent phonon generation mechanism by irradiation of an ultrashort pulse with a simple two-level model. Our derived formulation shows that both impulsive stimulated Raman scattering (ISRS) and impulsive absorption (IA) simultaneously occur, and phonon wave packets are generated in the electronic ground and excited states by ISRS and IA, respectively. We identify the dominant process from the amplitude of the phonon oscillation. For short pulse widths, ISRS is very small ...

  20. Influence of Doppler Bin Width on GNSS Detection Probabilities

    Geiger, Bernhard C

    2011-01-01

    The acquisition stage in GNSS receivers determines Doppler shifts and code phases of visible satellites. Acquisition is thus a search in two continuous dimensions, where the digital algorithms require a partitioning of the search space into cells. We present analytic expressions for the acquisition performance depending on the partitioning of the Doppler frequency domain. In particular, the impact of the number and width of Doppler bins is analyzed. The presented results are verified by simulations.