Are Proplyds the Low-Energy Counterpart of Clouds Populating the AGNs Broad Line Region?

Science.gov (United States)

Dottori, H.

2000-11-01

The stability of the clouds producing the broadening of permitted lines in A GNs is a challenge for the persistence of these features during the galactic nucleus active fase lifetime. The formation of succesive generations of clouds in this very agressive enviroment, seems not to be the more adequated scenarion to explain this phenomenon. Why should new clouds be formed in regions where the UV radiation is so intense as to destroy the previously existing ones? The discovery of proplyds in Orion and NGC3603, as well as in 30Dor, shows that the formation of stars with protostars with surrounding disk is a common phenomenon in HII regions with very different radiation fields. We discuss that as a mechanism to explain the persistence of the clouds in the AGNs broad line regions.

Hidden Broad-line Regions in Seyfert 2 Galaxies: From the Spectropolarimetric Perspective

International Nuclear Information System (INIS)

Du, Pu; Wang, Jian-Min; Zhang, Zhi-Xiang

2017-01-01

The hidden broad-line regions (BLRs) in Seyfert 2 galaxies, which display broad emission lines (BELs) in their polarized spectra, are a key piece of evidence in support of the unified model for active galactic nuclei (AGNs). However, the detailed kinematics and geometry of hidden BLRs are still not fully understood. The virial factor obtained from reverberation mapping of type 1 AGNs may be a useful diagnostic of the nature of hidden BLRs in type 2 objects. In order to understand the hidden BLRs, we compile six type 2 objects from the literature with polarized BELs and dynamical measurements of black hole masses. All of them contain pseudobulges. We estimate their virial factors, and find the average value is 0.60 and the standard deviation is 0.69, which agree well with the value of type 1 AGNs with pseudobulges. This study demonstrates that (1) the geometry and kinematics of BLR are similar in type 1 and type 2 AGNs of the same bulge type (pseudobulges), and (2) the small values of virial factors in Seyfert 2 galaxies suggest that, similar to type 1 AGNs, BLRs tend to be very thick disks in type 2 objects.

Simulations of the broad line region of NGC 5548 with CLOUDY code: Temperature determination

Directory of Open Access Journals (Sweden)

Ilić D.

2007-01-01

Full Text Available In this paper an analysis of the physical properties of the Broad Line Region (BLR of the active galaxy NGC 5548 is presented. Using the photoionization code CLOUDY and the measurements of Peterson et al. (2002, the physical conditions of the BLR are simulated and the BLR temperature is obtained. This temperature was compared to the temperature estimated with the Boltzmann-Plot (BP method (Popović et al. 2007. It was shown that the measured variability in the BLR temperature could be due to the change in the hydrogen density.

REVERBERATION AND PHOTOIONIZATION ESTIMATES OF THE BROAD-LINE REGION RADIUS IN LOW-z QUASARS

Energy Technology Data Exchange (ETDEWEB)

Negrete, C. Alenka [Instituto Nacional de Astrofisica, Optica y Electronica (Mexico); Dultzin, Deborah [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico (Mexico); Marziani, Paola [INAF, Astronomical Observatory of Padova, I-35122 Padova (Italy); Sulentic, Jack W., E-mail: cnegrete@inaoep.mx, E-mail: deborah@astro.unam.mx, E-mail: paola.marziani@oapd.inaf.it, E-mail: sulentic@iaa.es [Instituto de Astrofisica de Andalucia, E-18008 Granada (Spain)

2013-07-01

Black hole mass estimation in quasars, especially at high redshift, involves the use of single-epoch spectra with signal-to-noise ratio and resolution that permit accurate measurement of the width of a broad line assumed to be a reliable virial estimator. Coupled with an estimate of the radius of the broad-line region (BLR) this yields the black hole mass M{sub BH}. The radius of the BLR may be inferred from an extrapolation of the correlation between source luminosity and reverberation-derived r{sub BLR} measures (the so-called Kaspi relation involving about 60 low-z sources). We are exploring a different method for estimating r{sub BLR} directly from inferred physical conditions in the BLR of each source. We report here on a comparison of r{sub BLR} estimates that come from our method and from reverberation mapping. Our ''photoionization'' method employs diagnostic line intensity ratios in the rest-frame range 1400-2000 A (Al III {lambda}1860/Si III] {lambda}1892, C IV {lambda}1549/Al III {lambda}1860) that enable derivation of the product of density and ionization parameter with the BLR distance derived from the definition of the ionization parameter. We find good agreement between our estimates of the density, ionization parameter, and r{sub BLR} and those from reverberation mapping. We suggest empirical corrections to improve the agreement between individual photoionization-derived r{sub BLR} values and those obtained from reverberation mapping. The results in this paper can be exploited to estimate M{sub BH} for large samples of high-z quasars using an appropriate virial broadening estimator. We show that the width of the UV intermediate emission lines are consistent with the width of H{beta}, thereby providing a reliable virial broadening estimator that can be measured in large samples of high-z quasars.

The Different Nature in Seyfert 2 Galaxies With and Without Hidden Broad-Line Regions

OpenAIRE

Wu, Yu-Zhong; Zhang, En-Peng; Liang, Yan-Chun; Zhang, Cheng-Min; Zhao, Yong-Heng

2011-01-01

We compile a large sample of 120 Seyfert 2 galaxies (Sy2s) which contains 49 hidden broad-line region (HBLR) Sy2s and 71 non-HBLR Sy2s. From the difference in the power sources between two groups, we test if HBLR Sy2s are dominated by active galactic nuclei (AGNs), and if non-HBLR Sy2s are dominated by starbursts. We show that: (1) HBLR Sy2s have larger accretion rates than non-HBLR Sy2s; (2) HBLR Sy2s have larger \\Nev $\\lambda 14.32$/\\Neii $\\lambda 12.81$ and \\oiv $\\lambda 25.89$/\\Neii $\\lam...

Probing the accretion flow and emission-line regions of M81, the nearest broad-lined low-luminosity AGN

Science.gov (United States)

Barth, Aaron

2017-08-01

The nucleus of M81 is an object of singular importance as a template for low-luminosity accretion flows onto supermassive black holes. We propose to obtain a complete, small-aperture, high S/N STIS UV/optical spectrum of the M81 nucleus and multi-filter WFC3 imaging covering the UV through near-IR. Such data have never previously been obtained with HST; the only prior archival UV/optical spectra of M81 have low S/N, incomplete wavelength coverage, and are strongly contaminated by starlight. Combined with new Chandra X-ray data, our proposed observations will comprise the definitive reference dataset on the spectral energy distribution of this benchmark low-luminosity AGN. These data will provide unique new constraints on the possible contribution of a truncated thin accretion disk to the AGN emission spectrum, clarifying a fundamental property of low-luminosity accretion flows. The data will additionally provide new insights into broad-line region structure and black hole mass scaling relationships at the lowest AGN luminosities, and spatially resolved diagnostics of narrow-line region excitation conditions at unprecedented spatial resolution to assess the impact of the AGN on the ionization state of the gas in the host galaxy bulge.

Spectrophotometry of six broad absorption line QSOs

Science.gov (United States)

Junkkarinen, Vesa T.; Burbidge, E. Margaret; Smith, Harding E.

1987-01-01

Spectrophotometric observations of six broad absorption-line QSOs (BALQSOs) are presented. The continua and emission lines are compared with those in the spectra of QSOs without BALs. A statistically significant difference is found in the emission-line intensity ratio for (N V 1240-A)/(C IV 1549-A). The median value of (N V)/(C IV) for the BALQSOs is two to three times the median for QSOs without BALs. The absorption features of the BALQSOs are described, and the column densities and limits on the ionization structure of the BAL region are discussed. If the dominant ionization mechanism is photoionization, then it is likely that either the ionizing spectrum is steep or the abundances are considerably different from solar. Collisional ionization may be a significant factor, but it cannot totally dominate the ionization rate.

Unusual broad-line Mg II emitters among luminous galaxies in the baryon oscillation spectroscopic survey

International Nuclear Information System (INIS)

Roig, Benjamin; Blanton, Michael R.; Ross, Nicholas P.

2014-01-01

Many classes of active galactic nuclei (AGNs) have been observed and recorded since the discovery of Seyfert galaxies. In this paper, we examine the sample of luminous galaxies in the Baryon Oscillation Spectroscopic Survey. We find a potentially new observational class of AGNs, one with strong and broad Mg II λ2799 line emission, but very weak emission in other normal indicators of AGN activity, such as the broad-line Hα, Hβ, and the near-ultraviolet AGN continuum, leading to an extreme ratio of broad Hα/Mg II flux relative to normal quasars. Meanwhile, these objects' narrow-line flux ratios reveal AGN narrow-line regions with levels of activity consistent with the Mg II fluxes and in agreement with that of normal quasars. These AGN may represent an extreme case of the Baldwin effect, with very low continuum and high equivalent width relative to typical quasars, but their ratio of broad Mg II to broad Balmer emission remains very unusual. They may also be representative of a class of AGN where the central engine is observed indirectly with scattered light. These galaxies represent a small fraction of the total population of luminous galaxies (≅ 0.1%), but are more likely (about 3.5 times) to have AGN-like nuclear line emission properties than other luminous galaxies. Because Mg II is usually inaccessible for the population of nearby galaxies, there may exist a related population of broad-line Mg II emitters in the local universe which is currently classified as narrow-line emitters (Seyfert 2 galaxies) or low ionization nuclear emission-line regions.

CHEMICAL EVOLUTION OF THE UNIVERSE AT 0.7 < z < 1.6 DERIVED FROM ABUNDANCE DIAGNOSTICS OF THE BROAD-LINE REGION OF QUASARS

Energy Technology Data Exchange (ETDEWEB)

Sameshima, H. [Laboratory of Infrared High-resolution Spectroscopy, Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555 (Japan); Yoshii, Y.; Kawara, K., E-mail: sameshima@cc.kyoto-su.ac.jp [Institute of Astronomy, School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan)

2017-01-10

We present an analysis of Mg ii λ 2798 and Fe ii UV emission lines for archival Sloan Digital Sky Survey (SDSS) quasars to explore the diagnostics of the magnesium-to-iron abundance ratio in a broad-line region cloud. Our sample consists of 17,432 quasars selected from the SDSS Data Release 7 with a redshift range of 0.72 <  z  < 1.63. A strong anticorrelation between the Mg ii equivalent width (EW) and the Eddington ratio is found, while only a weak positive correlation is found between the Fe ii EW and the Eddington ratio. To investigate the origin of these differing behaviors of Mg ii and Fe ii emission lines, we perform photoionization calculations using the Cloudy code, where constraints from recent reverberation mapping studies are considered. We find from calculations that (1) Mg ii and Fe ii emission lines are created at different regions in a photoionized cloud, and (2) their EW correlations with the Eddington ratio can be explained by just changing the cloud gas density. These results indicate that the Mg ii/Fe ii flux ratio, which has been used as a first-order proxy for the Mg/Fe abundance ratio in chemical evolution studies with quasar emission lines, depends largely on the cloud gas density. By correcting this density dependence, we propose new diagnostics of the Mg/Fe abundance ratio for a broad-line region cloud. In comparing the derived Mg/Fe abundance ratios with chemical evolution models, we suggest that α -enrichment by mass loss from metal-poor intermediate-mass stars occurred at z  ∼ 2 or earlier.

GAMMA–GAMMA ABSORPTION IN THE BROAD LINE REGION RADIATION FIELDS OF GAMMA-RAY BLAZARS

Energy Technology Data Exchange (ETDEWEB)

Böttcher, Markus; Els, Paul, E-mail: Markus.Bottcher@nwu.ac.za [Centre for Space Research, North-West University, Potchefstroom, 2531 (South Africa)

2016-04-20

The expected level of γγ absorption in the Broad Line Region (BLR) radiation field of γ -ray loud Flat Spectrum Radio Quasars (FSRQs) is evaluated as a function of the location of the γ -ray emission region. This is done self-consistently with parameters inferred from the shape of the spectral energy distribution (SED) in a single-zone leptonic EC-BLR model scenario. We take into account all geometrical effects both in the calculation of the γγ opacity and the normalization of the BLR radiation energy density. As specific examples, we study the FSRQs 3C279 and PKS 1510-089, keeping the BLR radiation energy density at the location of the emission region fixed at the values inferred from the SED. We confirm previous findings that the optical depth due to γγ absorption in the BLR radiation field exceeds unity for both 3C279 and PKS 1510-089 for locations of the γ -ray emission region inside the inner boundary of the BLR. It decreases monotonically, with distance from the central engine and drops below unity for locations within the BLR. For locations outside the BLR, the BLR radiation energy density required for the production of GeV γ -rays rapidly increases beyond observational constraints, thus making the EC-BLR mechanism implausible. Therefore, in order to avoid significant γγ absorption by the BLR radiation field, the γ -ray emission region must therefore be located near the outer boundary of the BLR.

A REVERBERATION LAG FOR THE HIGH-IONIZATION COMPONENT OF THE BROAD-LINE REGION IN THE NARROW-LINE SEYFERT 1 Mrk 335

International Nuclear Information System (INIS)

Grier, C. J.; Peterson, B. M.; Pogge, R. W.; Martini, Paul; Zu, Y.; Kochanek, C. S.; Shappee, B. J.; Stanek, K. Z.; Araya Salvo, C.; Beatty, T. G.; Bird, J. C.; Denney, K. D.; Bentz, M. C.; Sergeev, S. G.; Borman, G. A.; Kaspi, S.; Bord, D. J.; Che, X.; Chen, C.; Cohen, S. A.

2012-01-01

We present the first results from a detailed analysis of photometric and spectrophotometric data on the narrow-line Seyfert 1 (NLS1) galaxy Mrk 335, collected over a 120 day span in the fall of 2010. From these data we measure the lag in the He II λ4686 broad emission line relative to the optical continuum to be 2.7 ± 0.6 days and the lag in the Hβλ4861 broad emission line to be 13.9 ± 0.9 days. Combined with the line width, the He II lag yields a black hole mass M BH = (2.6 ± 0.8) × 10 7 M ☉ . This measurement is consistent with measurements made using the Hβλ4861 line, suggesting that the He II emission originates in the same structure as Hβ, but at a much smaller radius. This constitutes the first robust lag measurement for a high-ionization line in an NLS1 galaxy and supports a scenario in which the He II emission originates from gas in virial motion rather than outflow.

A REVERBERATION LAG FOR THE HIGH-IONIZATION COMPONENT OF THE BROAD-LINE REGION IN THE NARROW-LINE SEYFERT 1 Mrk 335

Energy Technology Data Exchange (ETDEWEB)

Grier, C. J.; Peterson, B. M.; Pogge, R. W.; Martini, Paul; Zu, Y.; Kochanek, C. S.; Shappee, B. J.; Stanek, K. Z.; Araya Salvo, C.; Beatty, T. G.; Bird, J. C. [Department of Astronomy, The Ohio State University, 140 W 18th Avenue, Columbus, OH 43210 (United States); Denney, K. D. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Bentz, M. C. [Department of Physics and Astronomy, Georgia State University, Astronomy Offices, One Park Place South SE, Suite 700, Atlanta, GA 30303 (United States); Sergeev, S. G.; Borman, G. A. [Crimean Astrophysical Observatory, P/O Nauchny Crimea 98409 (Ukraine); Kaspi, S. [School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel); Bord, D. J. [Department of Natural Sciences, The University of Michigan-Dearborn, 4901 Evergreen Rd, Dearborn, MI 48128 (United States); Che, X. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 41809 (United States); Chen, C.; Cohen, S. A. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); and others

2012-01-15

We present the first results from a detailed analysis of photometric and spectrophotometric data on the narrow-line Seyfert 1 (NLS1) galaxy Mrk 335, collected over a 120 day span in the fall of 2010. From these data we measure the lag in the He II {lambda}4686 broad emission line relative to the optical continuum to be 2.7 {+-} 0.6 days and the lag in the H{beta}{lambda}4861 broad emission line to be 13.9 {+-} 0.9 days. Combined with the line width, the He II lag yields a black hole mass M{sub BH} = (2.6 {+-} 0.8) Multiplication-Sign 10{sup 7} M{sub Sun }. This measurement is consistent with measurements made using the H{beta}{lambda}4861 line, suggesting that the He II emission originates in the same structure as H{beta}, but at a much smaller radius. This constitutes the first robust lag measurement for a high-ionization line in an NLS1 galaxy and supports a scenario in which the He II emission originates from gas in virial motion rather than outflow.

Correlation between the line width and the line flux of the double-peaked broad Hα of 3C390.3

Science.gov (United States)

Zhang, Xue-Guang

2013-03-01

In this paper, we carefully check the correlation between the line width (second moment) and the line flux of the double-peaked broad Hα of the well-known mapped active galactic nucleus (AGN) 3C390.3 in order to show some further distinctions between double-peaked emitters and normal broad-line AGN. Based on the virialization assumption MBH ∝ RBLR × V2(BLR) and the empirical relation RBLR ∝ L˜0.5, one strong negative correlation between the line width and the line flux of the double-peaked broad lines should be expected for 3C390.3, such as the negative correlation confirmed for the mapped broad-line object NGC 5548, RBLR × V2(BLR) ∝ L˜0.5 × σ2 = constant. Moreover, based on the public spectra around 1995 from the AGN WATCH project for 3C390.3, one reliable positive correlation is found between the line width and the line flux of the double-peaked broad Hα. In the context of the proposed theoretical accretion disc model for double-peaked emitters, the unexpected positive correlation can be naturally explained, due to different time delays for the inner and outer parts of the disc-like broad-line region (BLR) of 3C390.3. Moreover, the virialization assumption is checked and found to be still available for 3C390.3. However, the time-varying size of the BLR of 3C390.3 cannot be expected by the empirical relation RBLR ∝ L˜0.5. In other words, the mean size of the BLR of 3C390.3 can be estimated by the continuum luminosity (line luminosity), while the continuum emission strengthening leads to the size of BLR decreasing (not increasing) in different moments for 3C390.3. Then, we compared our results of 3C390.3 with the previous results reported in the literature for the other double-peaked emitters, and found that before to clearly correct the effects from disc physical parameters varying (such as the effects of disc precession) for long-term observed line spectra, it is not so meaningful to discuss the correlation of the line parameters of double

A REVISED BROAD-LINE REGION RADIUS AND BLACK HOLE MASS FOR THE NARROW-LINE SEYFERT 1 NGC 4051

International Nuclear Information System (INIS)

Denney, K. D.; Watson, L. C.; Peterson, B. M.

2009-01-01

We present the first results from a high sampling rate, multimonth reverberation mapping campaign undertaken primarily at MDM Observatory with supporting observations from telescopes around the world. The primary goal of this campaign was to obtain either new or improved Hβ reverberation lag measurements for several relatively low luminosity active galactic nuclei (AGNs). We feature results for NGC 4051 here because, until now, this object has been a significant outlier from AGN scaling relationships, e.g., it was previously a ∼2-3σ outlier on the relationship between the broad-line region (BLR) radius and the optical continuum luminosity-the R BLR -L relationship. Our new measurements of the lag time between variations in the continuum and Hβ emission line made from spectroscopic monitoring of NGC 4051 lead to a measured BLR radius of R BLR = 1.87 +0.54 -0.50 light days and black hole mass of M BH = (1.73 +0.55 -0.52 ) x 10 6 M sun . This radius is consistent with that expected from the R BLR -L relationship, based on the present luminosity of NGC 4051 and the most current calibration of the relation by Bentz et al.. We also present a preliminary look at velocity-resolved Hβ light curves and time delay measurements, although we are unable to reconstruct an unambiguous velocity-resolved reverberation signal.

An Intrinsic Baldwin Effect in the H Beta Broad Emission Line in the Spectrum of NGC 5548

Science.gov (United States)

Gilbert, Karoline M.; Peterson, Bradley M.

2003-01-01

We investigate the possibility of an intrinsic Baldwin effect (i.e., nonlinear emission-line response to continuum variations) in the broad HP emission line of the active galaxy NGC 5548 using crosscorrelation techniques to remove light-travel time effects from the data. We find a nonlinear relationship between the HP emission line and continuum fluxes that is in good agreement with theoretical predictions. We suggest that similar analysis of multiple lines might provide a useful diagnostic of physical conditions in the broad-line region.

Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution

Energy Technology Data Exchange (ETDEWEB)

Czerny, B.; Panda, S.; Wildy, C.; Sniegowska, M. [Center for Theoretical Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland); Li, Yan-Rong; Wang, J.-M. [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049 (China); Hryniewicz, K.; Sredzinska, J. [Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw (Poland); Karas, V., E-mail: bcz@cft.edu.pl [Astronomical Institute, Academy of Sciences, Bocni II 1401, CZ-141 00 Prague (Czech Republic)

2017-09-10

The physical origin of the broad line region in active galactic nuclei is still unclear despite many years of observational studies. The reason is that the region is unresolved, and the reverberation mapping results imply a complex velocity field. We adopt a theory-motivated approach to identify the principal mechanism responsible for this complex phenomenon. We consider the possibility that the role of dust is essential. We assume that the local radiation pressure acting on the dust in the accretion disk atmosphere launches the outflow of material, but higher above the disk the irradiation from the central parts causes dust evaporation and a subsequent fallback. This failed radiatively accelerated dusty outflow is expected to represent the material forming low ionization lines. In this paper we formulate simple analytical equations to describe the cloud motion, including the evaporation phase. The model is fully described just by the basic parameters of black hole mass, accretion rate, black hole spin, and viewing angle. We study how the spectral line generic profiles correspond to this dynamic. We show that the virial factor calculated from our model strongly depends on the black hole mass in the case of enhanced dust opacity, and thus it then correlates with the line width. This could explain why the virial factor measured in galaxies with pseudobulges differs from that obtained from objects with classical bulges, although the trend predicted by the current version of the model is opposite to the observed trend.

STAR FORMATION IN SELF-GRAVITATING DISKS IN ACTIVE GALACTIC NUCLEI. II. EPISODIC FORMATION OF BROAD-LINE REGIONS

International Nuclear Information System (INIS)

WangJianmin; Du Pu; Ge Junqiang; Hu Chen; Baldwin, Jack A.; Ferland, Gary J.

2012-01-01

This is the second in a series of papers discussing the process and effects of star formation in the self-gravitating disk around the supermassive black holes in active galactic nuclei (AGNs). We have previously suggested that warm skins are formed above the star-forming (SF) disk through the diffusion of warm gas driven by supernova explosions. Here we study the evolution of the warm skins when they are exposed to the powerful radiation from the inner part of the accretion disk. The skins initially are heated to the Compton temperature, forming a Compton atmosphere (CAS) whose subsequent evolution is divided into four phases. Phase I is the duration of pure accumulation supplied by the SF disk. During phase II clouds begin to form due to line cooling and sink to the SF disk. Phase III is a period of preventing clouds from sinking to the SF disk through dynamic interaction between clouds and the CAS because of the CAS overdensity driven by continuous injection of warm gas from the SF disk. Finally, phase IV is an inevitable collapse of the entire CAS through line cooling. This CAS evolution drives the episodic appearance of broad-line regions (BLRs). We follow the formation of cold clouds through the thermal instability of the CAS during phases II and III, using linear analysis. Since the clouds are produced inside the CAS, the initial spatial distribution of newly formed clouds and angular momentum naturally follow the CAS dynamics, producing a flattened disk of clouds. The number of clouds in phases II and III can be estimated, as well as the filling factor of clouds in the BLR. Since the cooling function depends on the metallicity, the metallicity gradients that originate in the SF disk give rise to different properties of clouds in different radial regions. We find from the instability analysis that clouds have column density N H ∼ 22 cm –2 in the metal-rich regions whereas they have N H ∼> 10 22 cm –2 in the metal-poor regions. The metal-rich clouds

Broad line NMR study of modified polypropylene fibres

International Nuclear Information System (INIS)

Olcak, D.; Sevcovic, L.; Mucha, L.

1999-01-01

Study of drawn fibres prepared from an isostatic polypropylene modified by an ethylene aminoalkylacrylate copolymer has been done using the broad line of 1 H NMR. NMR spectra were measured on the set of fibres prepared with a draw ratio λ from 1 to 5.5 at two temperatures, one of them corresponding to the onset of segmental motion and the other one is the minddle of the temperature interval as determined by decrease of the second moment M 2 . Decomposition of the spectra into elementary components related to the amorphous, intermediate and crystalline regions of partially crystalline polymers has been made. The drawing of the fibres was found to enhance the chain mobility in the amorphous region and to restrain the molecular motion in the intermediate region. Such behaviour well supports conclusions predicted in the earlier study based on the spin-lattice relaxation time T 1 and dynamic mechanical data treated using the WLF theory. (Authors)

Line Shape Variability in a Sample of AGN with Broad Lines

Indian Academy of Sciences (India)

2016-01-27

Jan 27, 2016 ... We give here a comparative review of the line shape variability in a sample of five type 1 AGNs, those with broad emission lines in their spectra, of the data obtained from the international long-term optical monitoring campaign coordinated by the Special Astrophysical Observatory of the Russian Academy ...

PG 1700 + 518 - a low-redshift, broad absorption line QSO

International Nuclear Information System (INIS)

Pettini, M.; Boksenberg, A.

1985-01-01

The first high-resolution optical spectra and lower resolution UV spectra of PG 1700 + 518, the only known broad-absorption-line (BAL) QSO at low emission redshift (0.288) are presented. The optical data were obtained with the Isaac Newton Telescope on the island of La Palma and the UV data with the International Ultraviolet Explorer satellite. The outstanding feature of the optical spectrum is a strong, broad Mg II absorption trough, detached from the Mg II emission line and indicative of ejection velocities of between 7000 and 18,000 km/s. Also detected were narrow (FWHM = 350 km/s) Mg II absorption lines at absolute z = 0.2698, which are probably related to the mass ejection phenomenon. It is concluded that the emission-line spectrum is similar to that of other low-redshift QSOs although there are some obvious differences from typical BAL QSOs, most notably in the unusually low level of ionization of both emission-line and broad absorption line gas. 21 references

THE LICK AGN MONITORING PROJECT: BROAD-LINE REGION RADII AND BLACK HOLE MASSES FROM REVERBERATION MAPPING OF Hβ

International Nuclear Information System (INIS)

Bentz, Misty C.; Walsh, Jonelle L.; Barth, Aaron J.; Baliber, Nairn; Bennert, Vardha Nicola; Greene, Jenny E.; Hidas, Marton G.; Canalizo, Gabriela; Hiner, Kyle D.; Filippenko, Alexei V.; Ganeshalingam, Mohan; Lee, Nicholas; Li, Weidong; Serduke, Frank J. D.; Silverman, Jeffrey M.; Steele, Thea N.; Gates, Elinor L.; Malkan, Matthew A.; Minezaki, Takeo; Sakata, Yu

2009-01-01

We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z 6 -10 7 M sun and also the well-studied nearby active galactic nucleus (AGN) NGC 5548. Nine of the objects in the sample (including NGC 5548) showed optical variability of sufficient strength during the monitoring campaign to allow for a time lag to be measured between the continuum fluctuations and the response to these fluctuations in the broad Hβ emission. We present here the light curves for all the objects in this sample and the subsequent Hβ time lags for the nine objects where these measurements were possible. The Hβ lag time is directly related to the size of the broad-line region (BLR) in AGNs, and by combining the Hβ lag time with the measured width of the Hβ emission line in the variable part of the spectrum, we determine the virial mass of the central supermassive black hole in these nine AGNs. The absolute calibration of the black hole masses is based on the normalization derived by Onken et al., which brings the masses determined by reverberation mapping into agreement with the local M BH -σ * relationship for quiescent galaxies. We also examine the time lag response as a function of velocity across the Hβ line profile for six of the AGNs. The analysis of four leads to rather ambiguous results with relatively flat time lags as a function of velocity. However, SBS 1116+583A exhibits a symmetric time lag response around the line center reminiscent of simple models for circularly orbiting BLR clouds, and Arp 151 shows an asymmetric profile that is most easily explained by a simple gravitational infall model. Further investigation will be necessary to fully understand the constraints placed on the physical models of the BLR by the velocity-resolved response in these objects.

Stability of the Broad-line Region Geometry and Dynamics in Arp 151 Over Seven Years

Science.gov (United States)

Pancoast, A.; Barth, A. J.; Horne, K.; Treu, T.; Brewer, B. J.; Bennert, V. N.; Canalizo, G.; Gates, E. L.; Li, W.; Malkan, M. A.; Sand, D.; Schmidt, T.; Valenti, S.; Woo, J.-H.; Clubb, K. I.; Cooper, M. C.; Crawford, S. M.; Hönig, S. F.; Joner, M. D.; Kandrashoff, M. T.; Lazarova, M.; Nierenberg, A. M.; Romero-Colmenero, E.; Son, D.; Tollerud, E.; Walsh, J. L.; Winkler, H.

2018-04-01

The Seyfert 1 galaxy Arp 151 was monitored as part of three reverberation mapping campaigns spanning 2008–2015. We present modeling of these velocity-resolved reverberation mapping data sets using a geometric and dynamical model for the broad-line region (BLR). By modeling each of the three data sets independently, we infer the evolution of the BLR structure in Arp 151 over a total of 7 yr and constrain the systematic uncertainties in nonvarying parameters such as the black hole mass. We find that the BLR geometry of a thick disk viewed close to face-on is stable over this time, although the size of the BLR grows by a factor of ∼2. The dynamics of the BLR are dominated by inflow, and the inferred black hole mass is consistent for the three data sets, despite the increase in BLR size. Combining the inference for the three data sets yields a black hole mass and statistical uncertainty of log10({M}BH}/{M}ȯ ) = {6.82}-0.09+0.09 with a standard deviation in individual measurements of 0.13 dex.

OPTICAL MONITORING OF THE BROAD-LINE RADIO GALAXY 3C 390.3

International Nuclear Information System (INIS)

Dietrich, Matthias; Peterson, Bradley M.; Grier, Catherine J.; Bentz, Misty C.; Eastman, Jason; Frank, Stephan; Gonzalez, Raymond; Marshall, Jennifer L.; DePoy, Darren L.; Prieto, Jose L.

2012-01-01

We have undertaken a new ground-based monitoring campaign on the broad-line radio galaxy 3C 390.3 to improve the measurement of the size of the broad emission-line region and to estimate the black hole mass. Optical spectra and g-band images were observed in late 2005 for three months using the 2.4 m telescope at MDM Observatory. Integrated emission-line flux variations were measured for the hydrogen Balmer lines Hα, Hβ, Hγ, and for the helium line He IIλ4686, as well as g-band fluxes and the optical active galactic nucleus (AGN) continuum at λ = 5100 Å. The g-band fluxes and the optical AGN continuum vary simultaneously within the uncertainties, τ cent (0.2 ± 1.1) days. We find that the emission-line variations are delayed with respect to the variable g-band continuum by τ(Hα) 56.3 +2.4 –6.6 days, τ(Hβ) = 44.3 +3.0 –3.3 days, τ(Hγ) = 58.1 +4.3 –6.1 days, and τ(He II 4686) = 22.3 +6.5 –3.8 days. The blue and red peaks in the double-peaked line profiles, as well as the blue and red outer profile wings, vary simultaneously within ±3 days. This provides strong support for gravitationally bound orbital motion of the dominant part of the line-emitting gas. Combining the time delay of the strong Balmer emission lines of Hα and Hβ and the separation of the blue and red peaks in the broad double-peaked profiles in their rms spectra, we determine M vir bh = 1.77 +0.29 –0.31 × 10 8 M ☉ and using σ line of the rms spectra M vir bh 2.60 +0.23 –0.31 × 10 8 M ☉ for the central black hole of 3C 390.3, respectively. Using the inclination angle of the line-emitting region which is measured from superluminal motion detected in the radio range, accretion disk models to fit the optical double-peaked emission-line profiles, and X-ray observations, the mass of the black hole amounts to M bh = 0.86 +0.19 –0.18 × 10 9 M ☉ (peak separation) and M bh 1.26 +0.21 –0.16 × 10 9 M ☉ (σ line ), respectively. This result is consistent with the black

Using the Properties of Broad Absorption Line Quasars to Illuminate Quasar Structure

Science.gov (United States)

Yong, Suk Yee; King, Anthea L.; Webster, Rachel L.; Bate, Nicholas F.; O'Dowd, Matthew J.; Labrie, Kathleen

2018-06-01

A key to understanding quasar unification paradigms is the emission properties of broad absorption line quasars (BALQs). The fact that only a small fraction of quasar spectra exhibit deep absorption troughs blueward of the broad permitted emission lines provides a crucial clue to the structure of quasar emitting regions. To learn whether it is possible to discriminate between the BALQ and non-BALQ populations given the observed spectral properties of a quasar, we employ two approaches: one based on statistical methods and the other supervised machine learning classification, applied to quasar samples from the Sloan Digital Sky Survey. The features explored include continuum and emission line properties, in particular the absolute magnitude, redshift, spectral index, line width, asymmetry, strength, and relative velocity offsets of high-ionisation C IV λ1549 and low-ionisation Mg II λ2798 lines. We consider a complete population of quasars, and assume that the statistical distributions of properties represent all angles where the quasar is viewed without obscuration. The distributions of the BALQ and non-BALQ sample properties show few significant differences. None of the observed continuum and emission line features are capable of differentiating between the two samples. Most published narrow disk-wind models are inconsistent with these observations, and an alternative disk-wind model is proposed. The key feature of the proposed model is a disk-wind filling a wide opening angle with multiple radial streams of dense clumps.

OPTICAL MONITORING OF THE BROAD-LINE RADIO GALAXY 3C 390.3

Energy Technology Data Exchange (ETDEWEB)

Dietrich, Matthias; Peterson, Bradley M.; Grier, Catherine J.; Bentz, Misty C.; Eastman, Jason; Frank, Stephan; Gonzalez, Raymond; Marshall, Jennifer L.; DePoy, Darren L.; Prieto, Jose L., E-mail: dietrich@astronomy.ohio-state.edu [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States)

2012-09-20

We have undertaken a new ground-based monitoring campaign on the broad-line radio galaxy 3C 390.3 to improve the measurement of the size of the broad emission-line region and to estimate the black hole mass. Optical spectra and g-band images were observed in late 2005 for three months using the 2.4 m telescope at MDM Observatory. Integrated emission-line flux variations were measured for the hydrogen Balmer lines H{alpha}, H{beta}, H{gamma}, and for the helium line He II{lambda}4686, as well as g-band fluxes and the optical active galactic nucleus (AGN) continuum at {lambda} = 5100 A. The g-band fluxes and the optical AGN continuum vary simultaneously within the uncertainties, {tau}{sub cent} (0.2 {+-} 1.1) days. We find that the emission-line variations are delayed with respect to the variable g-band continuum by {tau}(H{alpha}) 56.3{sup +2.4}{sub -6.6} days, {tau}(H{beta}) = 44.3{sup +3.0}{sub -3.3} days, {tau}(H{gamma}) = 58.1{sup +4.3}{sub -6.1} days, and {tau}(He II 4686) = 22.3{sup +6.5}{sub -3.8} days. The blue and red peaks in the double-peaked line profiles, as well as the blue and red outer profile wings, vary simultaneously within {+-}3 days. This provides strong support for gravitationally bound orbital motion of the dominant part of the line-emitting gas. Combining the time delay of the strong Balmer emission lines of H{alpha} and H{beta} and the separation of the blue and red peaks in the broad double-peaked profiles in their rms spectra, we determine M {sup vir}{sub bh} = 1.77{sup +0.29}{sub -0.31} Multiplication-Sign 10{sup 8} M{sub Sun} and using {sigma}{sub line} of the rms spectra M {sup vir}{sub bh} 2.60{sup +0.23}{sub -0.31} Multiplication-Sign 10{sup 8} M{sub Sun} for the central black hole of 3C 390.3, respectively. Using the inclination angle of the line-emitting region which is measured from superluminal motion detected in the radio range, accretion disk models to fit the optical double-peaked emission-line profiles, and X-ray observations

Optical Variability of Narrow-line and Broad-line Seyfert 1 Galaxies

Science.gov (United States)

Rakshit, Suvendu; Stalin, C. S.

2017-06-01

We studied the optical variability (OV) of a large sample of narrow-line Seyfert 1 (NLSy1) and broad-line Seyfert 1 (BLSy1) galaxies with z anti-correlated with Fe II strength but correlated with the width of the Hβ line. The well-known anti-correlation of variability-luminosity and the variability-Eddington ratio is present in our data. Among the radio-loud sample, variability amplitude is found to be correlated with radio-loudness and radio-power, suggesting that jets also play an important role in the OV in radio-loud objects, in addition to the Eddington ratio, which is the main driving factor of OV in radio-quiet sources.

Extreme Variability in a Broad Absorption Line Quasar

Energy Technology Data Exchange (ETDEWEB)

Stern, Daniel; Jun, Hyunsung D. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Mail Stop 169-221, Pasadena, CA 91109 (United States); Graham, Matthew J.; Djorgovski, S. G.; Donalek, Ciro; Drake, Andrew J.; Mahabal, Ashish A.; Steidel, Charles C. [California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125 (United States); Arav, Nahum; Chamberlain, Carter [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States); Barth, Aaron J. [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697 (United States); Glikman, Eilat, E-mail: daniel.k.stern@jpl.nasa.gov [Department of Physics, Middlebury College, Middlebury, VT 05753 (United States)

2017-04-20

CRTS J084133.15+200525.8 is an optically bright quasar at z = 2.345 that has shown extreme spectral variability over the past decade. Photometrically, the source had a visual magnitude of V ∼ 17.3 between 2002 and 2008. Then, over the following five years, the source slowly brightened by approximately one magnitude, to V ∼ 16.2. Only ∼1 in 10,000 quasars show such extreme variability, as quantified by the extreme parameters derived for this quasar assuming a damped random walk model. A combination of archival and newly acquired spectra reveal the source to be an iron low-ionization broad absorption line quasar with extreme changes in its absorption spectrum. Some absorption features completely disappear over the 9 years of optical spectra, while other features remain essentially unchanged. We report the first definitive redshift for this source, based on the detection of broad H α in a Keck/MOSFIRE spectrum. Absorption systems separated by several 1000 km s{sup −1} in velocity show coordinated weakening in the depths of their troughs as the continuum flux increases. We interpret the broad absorption line variability to be due to changes in photoionization, rather than due to motion of material along our line of sight. This source highlights one sort of rare transition object that astronomy will now be finding through dedicated time-domain surveys.

Evidence for Broad-Line Region Outflows and Their Impact on Black Hole Mass Measurements

DEFF Research Database (Denmark)

Denney, K. D.; Assef, R. J.; Horne, K.

2012-01-01

could not be fully and accurately interpreted from the 1D velocity-resolved reverberation signal. From the VDM, an outflow component to the emission remains possible but appears to be in addition to an underlying, disk-like BLR structure consistent in size with the measured reverberation lag. The black...... hole (BH) mass derived from this data is therefore secure from any uncertainties possibly derived from gravitationally unbound gas contributing to the emission. Additionally, we demonstrate that BLR emission from the C IV ¿1549 broad emission line can reliably be used as a virial BH mass estimator...

Optical Variability of Narrow-line and Broad-line Seyfert 1 Galaxies

Energy Technology Data Exchange (ETDEWEB)

Rakshit, Suvendu; Stalin, C. S., E-mail: suvenduat@gmail.com [Indian Institute of Astrophysics, Block II, Koramangala, Bangalore-560034 (India)

2017-06-20

We studied the optical variability (OV) of a large sample of narrow-line Seyfert 1 (NLSy1) and broad-line Seyfert 1 (BLSy1) galaxies with z < 0.8 to investigate any differences in their OV properties. Using archival optical V -band light curves from the Catalina Real Time Transient Survey that span 5–9 years and modeling them using damped random walk, we estimated the amplitude of variability. We found that NLSy1 galaxies as a class show lower amplitude of variability than their broad-line counterparts. In the sample of both NLSy1 and BLSy1 galaxies, radio-loud sources are found to have higher variability amplitude than radio-quiet sources. Considering only sources that are detected in the X-ray band, NLSy1 galaxies are less optically variable than BLSy1 galaxies. The amplitude of variability in the sample of both NLSy1 and BLSy1 galaxies is found to be anti-correlated with Fe ii strength but correlated with the width of the H β line. The well-known anti-correlation of variability–luminosity and the variability–Eddington ratio is present in our data. Among the radio-loud sample, variability amplitude is found to be correlated with radio-loudness and radio-power, suggesting that jets also play an important role in the OV in radio-loud objects, in addition to the Eddington ratio, which is the main driving factor of OV in radio-quiet sources.

Superluminous Transients at AGN Centers from Interaction between Black Hole Disk Winds and Broad-line Region Clouds

Energy Technology Data Exchange (ETDEWEB)

Moriya, Takashi J.; Tanaka, Masaomi; Ohsuga, Ken [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Morokuma, Tomoki, E-mail: takashi.moriya@nao.ac.jp [Institute of Astronomy, Graduate School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan)

2017-07-10

We propose that superluminous transients that appear at central regions of active galactic nuclei (AGNs) such as CSS100217:102913+404220 (CSS100217) and PS16dtm, which reach near- or super-Eddington luminosities of the central black holes, are powered by the interaction between accretion-disk winds and clouds in broad-line regions (BLRs) surrounding them. If the disk luminosity temporarily increases by, e.g., limit–cycle oscillations, leading to a powerful radiatively driven wind, strong shock waves propagate in the BLR. Because the dense clouds in the AGN BLRs typically have similar densities to those found in SNe IIn, strong radiative shocks emerge and efficiently convert the ejecta kinetic energy to radiation. As a result, transients similar to SNe IIn can be observed at AGN central regions. Since a typical black hole disk-wind velocity is ≃0.1 c , where c is the speed of light, the ejecta kinetic energy is expected to be ≃10{sup 52} erg when ≃1 M {sub ⊙} is ejected. This kinetic energy is transformed to radiation energy in a timescale for the wind to sweep up a similar mass to itself in the BLR, which is a few hundred days. Therefore, both luminosities (∼10{sup 44} erg s{sup −1}) and timescales (∼100 days) of the superluminous transients from AGN central regions match those expected in our interaction model. If CSS100217 and PS16dtm are related to the AGN activities triggered by limit–cycle oscillations, they become bright again in coming years or decades.

Study of the hydration of globular proteins by broad NMR lines method

Energy Technology Data Exchange (ETDEWEB)

Blicharska, B [Uniwersytet Jagiellonski, Krakow (Poland). Instytut Fizyki

1973-01-01

Spectra of proteins and polypeptides obtained by means of a NMR broad line spectrometer consist of broad and thin lines. These broad and thin lines are attributed to proteins and to water absorbed on the surfaces of proteins respectively. The behaviour of the thin line in the spectra of lyophilizated albumin of the egg white has been studied in the temperature range from -42 to 20/sup 0/C. The amount of water has been found by the simple method of weighing and has been equal about 7% of the total weight. It has been found that the water absorbed on the surface of the lyophilizated proteins gives a thinner line in comparison to the water absorbed on molecules of proteins in water solutions and that the correlation time is about 10/sup 3/ times greater.

Broad-line high-excitation gas in the elliptical galaxy NGC5128

International Nuclear Information System (INIS)

Phillips, M.M.; Taylor, K.; Axon, D.J.; Atherton, P.D.; Hook, R.N.

1984-01-01

A faint, but extensive component of broad-line ionized gas has been discovered in the peculiar giant elliptical galaxy NGC5128. This component has a radically different spatial distribution from the well-studied rotating photoionized gas associated with the dust lane although the velocity fields of the two components are similar. The origin of the broad-line gas is considered as its possible relation to the active nucleus and the X-ray jet discussed. (author)

Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database

DEFF Research Database (Denmark)

Peterson, B. M.; Ferrarese, L.; Gilbert, K. M.

2004-01-01

We present improved black hole masses for 35 active galactic nuclei (AGNs) based on a complete and consistent reanalysis of broad emission-line reverberation-mapping data. From objects with multiple line measurements, we find that the highest precision measure of the virial product is obtained...

Clues to quasar broad-line region geometry and kinematics

NARCIS (Netherlands)

Vestergaard, M; Wilkes, BJ; Barthel, PD

2000-01-01

We present evidence that the high-velocity C IV lambda 1549 emission-line gas of radio-loud quasars may originate in a disklike configuration, in close proximity to the accretion disk often assumed to emit the low-ionization lines. For a sample of 36 radio-loud z approximate to 2 quasars, we find

Dust inflated accretion disc as the origin of the broad line region in active galactic nuclei

Science.gov (United States)

Baskin, Alexei; Laor, Ari

2018-02-01

The broad line region (BLR) in active galactic nuclei (AGNs) is composed of dense gas (˜1011 cm-3) on sub-pc scale, which absorbs about 30 per cent of the ionizing continuum. The outer size of the BLR is likely set by dust sublimation, and its density by the incident radiation pressure compression (RPC). But, what is the origin of this gas, and what sets its covering factor (CF)? Czerny & Hryniewicz (2011) suggested that the BLR is a failed dusty wind from the outer accretion disc. We explore the expected dust properties, and the implied BLR structure. We find that graphite grains sublimate only at T ≃ 2000 K at the predicted density of ˜1011 cm-3, and therefore large graphite grains (≥0.3 μm) survive down to the observed size of the BLR, RBLR. The dust opacity in the accretion disc atmosphere is ˜50 times larger than previously assumed, and leads to an inflated torus-like structure, with a predicted peak height at RBLR. The illuminated surface of this torus-like structure is a natural place for the BLR. The BLR CF is mostly set by the gas metallicity, the radiative accretion efficiency, a dynamic configuration and ablation by the incident optical-UV continuum. This model predicts that the BLR should extend inwards of RBLR to the disc radius where the surface temperature is ≃2000 K, which occurs at Rin ≃ 0.18RBLR. The value of Rin can be tested by reverberation mapping of the higher ionization lines, predicted by RPC to peak well inside RBLR. The dust inflated disc scenario can also be tested based on the predicted response of RBLR and the CF to changes in the AGN luminosity and accretion rate.

A RADIAL VELOCITY TEST FOR SUPERMASSIVE BLACK HOLE BINARIES AS AN EXPLANATION FOR BROAD, DOUBLE-PEAKED EMISSION LINES IN ACTIVE GALACTIC NUCLEI

Energy Technology Data Exchange (ETDEWEB)

Liu, Jia; Halpern, Jules P. [Astronomy Department, Columbia University, 550 West 120th Street, New York, NY 10027 (United States); Eracleous, Michael [Department of Astronomy and Institute for Gravitation and The Cosmos, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States)

2016-01-20

One of the proposed explanations for the broad, double-peaked Balmer emission lines observed in the spectra of some active galactic nuclei (AGNs) is that they are associated with sub-parsec supermassive black hole (SMBH) binaries. Here, we test the binary broad-line region hypothesis through several decades of monitoring of the velocity structure of double-peaked Hα emission lines in 13 low-redshift, mostly radio-loud AGNs. This is a much larger set of objects compared to an earlier test by Eracleous et al. and we use much longer time series for the three objects studied in that paper. Although systematic changes in radial velocity can be traced in many of their lines, they are demonstrably not like those of a spectroscopic binary in a circular orbit. Any spectroscopic binary period must therefore be much longer than the span of the monitoring (assuming a circular orbit), which in turn would require black hole masses that exceed by 1–2 orders of magnitude the values obtained for these objects using techniques such as reverberation mapping and stellar velocity dispersion. Moreover, the response of the double-peaked Balmer line profiles to fluctuations of the ionizing continuum and the shape of the Lyα profiles are incompatible with an SMBH binary. The binary broad-line region hypothesis is therefore disfavored. Other processes evidently shape these line profiles and cause the long-term velocity variations of the double peaks.

Quasar outflow energetics from broad absorption line variability

Science.gov (United States)

McGraw, S. M.; Shields, J. C.; Hamann, F. W.; Capellupo, D. M.; Herbst, H.

2018-03-01

Quasar outflows have long been recognized as potential contributors to the co-evolution between supermassive black holes (SMBHs) and their host galaxies. The role of outflows in active galactic nucleus (AGN) feedback processes can be better understood by placing observational constraints on wind locations and kinetic energies. We utilize broad absorption line (BAL) variability to investigate the properties of a sample of 71 BAL quasars with P V broad absorption. The presence of P V BALs indicates that other BALs like C IV are saturated, such that variability in those lines favours clouds crossing the line of sight. We use these constraints with measurements of BAL variability to estimate outflow locations and energetics. Our data set consists of multiple-epoch spectra from the Sloan Digital Sky Survey and MDM Observatory. We detect significant (4σ) BAL variations from 10 quasars in our sample over rest-frame time-scales between ≤0.2-3.8 yr. Our derived distances for the 10 variable outflows are nominally ≲ 1-10 pc from the SMBH using the transverse-motion scenario, and ≲ 100-1000 pc from the central source using ionization-change considerations. These distances, in combination with the estimated high outflow column densities (i.e. NH ≳ 1022 cm-2), yield outflow kinetic luminosities between ˜ 0.001 and 1 times the bolometric luminosity of the quasar, indicating that many absorber energies within our sample are viable for AGN feedback.

Detection of broad ultraviolet Fe II lines in the spectrum of NGC 1068

International Nuclear Information System (INIS)

Snijders, M.A.J.; Netzer, Hagai; Boksenberg, A.

1986-01-01

Ultraviolet observations of the nucleus of NGC 1068, obtained by the IUE over a period of 5 yr, are combined to give a high signal-to-noise spectrum of this source. The ultraviolet stellar continuum, obtained by comparison with ground-based data, is subtracted to show the nuclear non-stellar component. The resulting spectrum shows clearly the presence of strong broad FeII emission bands similar to those observed in many broad-line objects. Broad profiles are also seen in other strong emission lines. These observations confirm the recent discovery of an optical Seyfert type 1 spectrum in NGC 1068. (author)

THE DIFFERENCES IN THE TORUS GEOMETRY BETWEEN HIDDEN AND NON-HIDDEN BROAD LINE ACTIVE GALACTIC NUCLEI

Energy Technology Data Exchange (ETDEWEB)

Ichikawa, Kohei; Ueda, Yoshihiro [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Packham, Christopher; Lopez-Rodriguez, Enrique; Alsip, Crystal D. [Department of Physics and Astronomy, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249 (United States); Almeida, Cristina Ramos; Ramos, Andrés Asensio; González-Martín, Omaira [Instituto de Astrofísica de Canarias, C/Vía Láctea, s/n, E-38205 La Laguna, Tenerife (Spain); Alonso-Herrero, Almudena [Instituto de Física de Cantabria, CSIC-Universidad de Cantabria, E-39005 Santander (Spain); Díaz-Santos, Tanio [Spitzer Science Center, California Institute of Technology, MS 220-6, Pasadena, CA 91125 (United States); Elitzur, Moshe [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506-0055 (United States); Hönig, Sebastian F. [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Imanishi, Masatoshi [Subaru Telescope, 650 North A’ohoku Place, Hilo, HI 96720 (United States); Levenson, Nancy A. [Gemini Observatory, Southern Operations Center, c/o AURA, Casilla 603, La Serena (Chile); Mason, Rachel E. [Gemini Observatory, Northern Operations Center, 670 N. A’ohoku Place, Hilo, HI 96720 (United States); Perlman, Eric S., E-mail: ichikawa@kusastro.kyoto-u.ac.jp [Department of Physics and Space Sciences, 150 W. University Blvd., Florida Institute of Technology, Melbourne, FL 32901 (United States)

2015-04-20

We present results from the fitting of infrared (IR) spectral energy distributions of 21 active galactic nuclei (AGNs) with clumpy torus models. We compiled high spatial resolution (∼0.3–0.7 arcsec) mid-IR (MIR) N-band spectroscopy, Q-band imaging, and nuclear near- and MIR photometry from the literature. Combining these nuclear near- and MIR observations, far-IR photometry, and clumpy torus models enables us to put constraints on the torus properties and geometry. We divide the sample into three types according to the broad line region (BLR) properties: type-1s, type-2s with scattered or hidden broad line region (HBLR) previously observed, and type-2s without any published HBLR signature (NHBLR). Comparing the torus model parameters gives us the first quantitative torus geometrical view for each subgroup. We find that NHBLR AGNs have smaller torus opening angles and larger covering factors than HBLR AGNs. This suggests that the chance to observe scattered (polarized) flux from the BLR in NHBLR could be reduced by the dual effects of (a) less scattering medium due to the reduced scattering volume given the small torus opening angle and (b) the increased torus obscuration between the observer and the scattering region. These effects give a reasonable explanation for the lack of observed HBLR in some type-2 AGNs.

Observing broad-absorption line quasars with Spectrum-Rontgen-Gamma

DEFF Research Database (Denmark)

Singh, K.P.; Schnopper, H.W.; Westergaard, Niels Jørgen Stenfeldt

1998-01-01

Broad-absorption line quasars are found to have extremely weak soft X-ray emission when compared with other optically selected quasars. In the only example of PHL 5200 for which a detailed X-ray spectrum has been obtained with ASCA, strong absorption in the source appears to be responsible...

Constraining The Abundance Of Massive Black Hole Binaries By Spectroscopic Monitoring Of Quasars With Offset Broad Emission Lines

Science.gov (United States)

Liu, Xin; Shen, Y.

2012-05-01

A fraction of quasars have long been known to show significant bulk velocity offsets (of a few hundred to thousands of km/s) in the broad permitted emission lines with respect to host galaxy systemic redshift. Various scenarios may explain these features such as massive black hole binaries or broad line region gas kinematics. As previously demonstrated by the dedicated work of Eracleous and colleagues, long-term spectroscopic monitoring provides a promising test to discriminate between alternative scenarios. Here, we present a sample of 300 shifted-line quasars homogeneously selected from the SDSS DR7. For 60 of them, we have conducted second-epoch optical spectra using MMT/BCS, ARC 3.5m/DIS, and/or FLWO 1.5m/FAST. These new observations, combined with the existing SDSS spectra, enable us to constrain the velocity drifts of these shifted broad lines with time baselines of a few years up to a decade. Previous work has been focusing on objects with extreme velocity offsets: > 1000 km/s. Our work extends to the parameter space of smaller velocity offsets, where larger velocity drifts would be expected in the binary scenario. Our results may be used to identify strong candidates for and to constrain the abundance of massive black hole binaries, which are expected in the hierarchical universe, but have so far been illusive.

Hidden Broad Line Seyfert 2 Galaxies in the CfA and 12micron Samples

OpenAIRE

Tran, Hien D.

2001-01-01

We report the results of a spectropolarimetric survey of the CfA and 12micron samples of Seyfert 2 galaxies (S2s). Polarized (hidden) broad line regions (HBLRs) are confirmed in a number of galaxies, and several new cases (F02581-1136, MCG -3-58-7, NGC 5995, NGC 6552, NGC 7682) are reported. The 12micron S2 sample shows a significantly higher incidence of HBLR (50%) than its CfA counterpart (30%), suggesting that the latter may be incomplete in hidden AGNs. Compared to the non-HBLR S2s, the H...

SN 2009bb: A PECULIAR BROAD-LINED TYPE Ic SUPERNOVA ,

International Nuclear Information System (INIS)

Pignata, Giuliano; Stritzinger, Maximilian; Phillips, M. M.; Morrell, Nidia; Boldt, Luis; Campillay, Abdo; Contreras, Carlos; Gonzalez, Sergio; Krzeminski, Wojtek; Roth, Miguel; Salgado, Francisco; Soderberg, Alicia; Mazzali, Paolo; Anderson, J. P.; Folatelli, Gaston; Foerster, Francisco; Hamuy, Mario; Maza, Jose; Levesque, Emily M.; Rest, Armin

2011-01-01

Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudobolometric light curve of SN 2009bb suggests that 4.1 ± 1.9 M sun of material was ejected with 0.22 ± 0.06 M sun of it being 56 Ni. The resulting kinetic energy is 1.8 ± 0.7 x 10 52 erg. This, together with an absolute peak magnitude of M B = -18.36 ± 0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission and high metallicity of its environment makes SN 2009bb a peculiar object. Similar to the case for gamma-ray bursts (GRBs), we find that the bulk explosion parameters of SN 2009bb cannot account for the copious energy coupled to relativistic ejecta, and conclude that another energy reservoir (a central engine) is required to power the radio emission. Nevertheless, the analysis of the SN 2009bb nebular spectrum suggests that the failed GRB detection is not imputable to a large angle between the line-of-sight and the GRB beamed radiation. Therefore, if a GRB was produced during the SN 2009bb explosion, it was below the threshold of the current generation of γ-ray instruments.

Simultaneous detection and analysis of optical and ultraviolet broad emission lines in quasars at z 2.2

Science.gov (United States)

Bisogni, S.; di Serego Alighieri, S.; Goldoni, P.; Ho, L. C.; Marconi, A.; Ponti, G.; Risaliti, G.

2017-06-01

We studied the spectra of six z 2.2 quasars obtained with the X-shooter spectrograph at the Very Large Telescope. The redshift of these sources and the X-shooter's spectral coverage allow us to cover the rest of the spectral range 1200-7000 Å for the simultaneous detection of optical and ultraviolet lines emitted by the broad-line region. Simultaneous measurements, avoiding issues related to quasars variability, help us understand the connection between the different broad-line region line profiles generally used as virial estimators of black hole masses in quasars. The goal of this work is to compare the different emission lines for each object to check on the reliability of Hα, Mg II and C iv with respect to Hβ. Hα and Mg II linewidths correlate well with Hβ, while C iv shows a poorer correlation, due to the presence of strong blueshifts and asymmetries in the profile. We compared our sample with the only other two whose spectra were taken with the same instrument and for all examined lines our results are in agreement with the ones obtained with X-shooter at z 1.5-1.7. We finally evaluate C III] as a possible substitute of C iv in the same spectral range and find that its behaviour is more coherent with those of the other lines: we believe that, when a high quality spectrum such as the ones we present is available and a proper modelization with the Fe II and Fe III emissions is performed, it is more appropriate to use this line than that of C iv if not corrected for the contamination by non-virialized components. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile, under programme 086.B-0320(A).The reduced spectra (FITS files) are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/603/A1

The case for cases B and C: intrinsic hydrogen line ratios of the broad-line region of active galactic nuclei, reddenings, and accretion disc sizes

Science.gov (United States)

Gaskell, C. Martin

2017-05-01

Low-redshift active galactic nuclei (AGNs) with extremely blue optical spectral indices are shown to have a mean, velocity-averaged, broad-line Hα/Hβ ratio of ≈2.72 ± 0.04, consistent with a Baker-Menzel Case B value. Comparison of a wide range of properties of the very bluest AGNs with those of a luminosity-matched subset of the Dong et al. blue AGN sample indicates that the only difference is the internal reddening. Ultraviolet fluxes are brighter for the bluest AGNs by an amount consistent with the flat AGN reddening curve of Gaskell et al. The lack of a significant difference in the GALEX (far-ultraviolet-near-ultraviolet) colour index strongly rules out a steep Small Magellanic Cloud-like reddening curve and also argues against an intrinsically harder spectrum for the bluest AGNs. For very blue AGNs, the Ly α/Hβ ratio is also consistent with being the Case B value. The Case B ratios provide strong support for the self-shielded broad-line model of Gaskell, Klimek & Nazarova. It is proposed that the greatly enhanced Ly α/Hβ ratio at very high velocities is a consequence of continuum fluorescence in the Lyman lines (Case C). Reddenings of AGNs mean that the far-UV luminosity is often underestimated by up to an order of magnitude. This is a major factor causing the discrepancies between measured accretion disc sizes and the predictions of simple accretion disc theory. Dust covering fractions for most AGNs are lower than has been estimated. The total mass in lower mass supermassive black holes must be greater than hitherto estimated.

Broad Absorption Line Quasar catalogues with Supervised Neural Networks

International Nuclear Information System (INIS)

Scaringi, Simone; Knigge, Christian; Cottis, Christopher E.; Goad, Michael R.

2008-01-01

We have applied a Learning Vector Quantization (LVQ) algorithm to SDSS DR5 quasar spectra in order to create a large catalogue of broad absorption line quasars (BALQSOs). We first discuss the problems with BALQSO catalogues constructed using the conventional balnicity and/or absorption indices (BI and AI), and then describe the supervised LVQ network we have trained to recognise BALQSOs. The resulting BALQSO catalogue should be substantially more robust and complete than BI-or AI-based ones.

Partial dust obscuration in active galactic nuclei as a cause of broad-line profile and lag variability, and apparent accretion disc inhomogeneities

Science.gov (United States)

Gaskell, C. Martin; Harrington, Peter Z.

2018-04-01

The profiles of the broad emission lines of active galactic nuclei (AGNs) and the time delays in their response to changes in the ionizing continuum ("lags") give information about the structure and kinematics of the inner regions of AGNs. Line profiles are also our main way of estimating the masses of the supermassive black holes (SMBHs). However, the profiles often show ill-understood, asymmetric structure and velocity-dependent lags vary with time. Here we show that partial obscuration of the broad-line region (BLR) by outflowing, compact, dusty clumps produces asymmetries and velocity-dependent lags similar to those observed. Our model explains previously inexplicable changes in the ratios of the hydrogen lines with time and velocity, the lack of correlation of changes in line profiles with variability of the central engine, the velocity dependence of lags, and the change of lags with time. We propose that changes on timescales longer than the light-crossing time do not come from dynamical changes in the BLR, but are a natural result of the effect of outflowing dusty clumps driven by radiation pressure acting on the dust. The motion of these clumps offers an explanation of long-term changes in polarization. The effects of the dust complicate the study of the structure and kinematics of the BLR and the search for sub-parsec SMBH binaries. Partial obscuration of the accretion disc can also provide the local fluctuations in luminosity that can explain sizes deduced from microlensing.

Broad-lined Supernova 2016coi with a Helium Envelope

Energy Technology Data Exchange (ETDEWEB)

Yamanaka, Masayuki [Department of Physics, Faculty of Science and Engineering, Konan University, Okamoto, Kobe, Hyogo 658-8501 (Japan); Nakaoka, Tatsuya; Kawabata, Miho [Department of Physical Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan); Tanaka, Masaomi [National Astronomical Observatory of Japan, National Institutes of Natural Sciences, Osawa, Mitaka, Tokyo 181-8588 (Japan); Maeda, Keiichi [Department of Astronomy, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); Honda, Satoshi; Hosoya, Kensuke; Karita, Mayu; Morihana, Kumiko [Nishi-Harima Astronomical Observatory, Center for Astronomy, University of Hyogo, 407-2 Nishigaichi, Sayo-cho, Sayo, Hyogo 679-5313 (Japan); Hanayama, Hidekazu [Ishigakijima Astronomical Observatory, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 1024-1 Arakawa, Ishigaki, Okinawa 907-0024 (Japan); Morokuma, Tomoki [Institute of Astronomy, Graduate School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Imai, Masataka [Department of Cosmosciences, Graduate School of Science, Hokkaido University, Kita 10 Nishi8, Kita-ku, Sapporo 060-0810 (Japan); Kinugasa, Kenzo [Nobeyama Radio Observatory, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 462-2 Nobeyama, Minamimaki, Minamisaku, Nagano 384-1305 (Japan); Murata, Katsuhiro L. [Department of Astrophysics, Nagoya University, Chikusa-ku, Nagoya 464-8602 (Japan); Nishimori, Takefumi; Gima, Hirotaka; Ito, Ayano; Morikawa, Yuto; Murakami, Kotone [Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065 (Japan); Hashimoto, Osamu, E-mail: yamanaka@center.konan-u.ac.jp [Gunma Astronomical Observatory, Takayama, Gunma 377-0702 (Japan); and others

2017-03-01

We present the early-phase spectra and the light curves of the broad-lined (BL) supernova (SN) 2016coi from t = 7 to 67 days after the estimated explosion date. This SN was initially reported as a BL Type SN Ic (SN Ic-BL). However, we found that spectra up to t = 12 days exhibited the He i λ 5876, λ 6678, and λ 7065 absorption lines. We show that the smoothed and blueshifted spectra of normal SNe Ib are remarkably similar to the observed spectrum of SN 2016coi. The line velocities of SN 2016coi were similar to those of SNe Ic-BL and significantly faster than those of SNe Ib. Analyses of the line velocity and light curve suggest that the kinetic energy and the total ejecta mass of SN 2016coi are similar to those of SNe Ic-BL. Together with BL SNe 2009bb and 2012ap, for which the detection of He i was also reported, these SNe could be transitional objects between SNe Ic-BL and SNe Ib, and be classified as BL Type “Ib” SNe (SNe “Ib”-BL). Our work demonstrates the diversity of the outermost layer in BL SNe, which should be related to the variety of the evolutionary paths.

EVOLUTION AND HYDRODYNAMICS OF THE VERY BROAD X-RAY LINE EMISSION IN SN 1987A

Energy Technology Data Exchange (ETDEWEB)

Dewey, D.; Canizares, C. R. [MIT Kavli Institute, Cambridge, MA 02139 (United States); Dwarkadas, V. V. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Haberl, F.; Sturm, R., E-mail: dd@space.mit.edu, E-mail: vikram@oddjob.uchicago.edu [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, Garching D-85748 (Germany)

2012-06-20

Observations of SN 1987A by the Chandra High Energy Transmission Grating (HETG) in 1999 and the XMM-Newton Reflection Grating Spectrometer (RGS) in 2003 show very broad (v-b) lines with a full width at half-maximum (FWHM) of order 10{sup 4} km s{sup -1}; at these times the blast wave (BW) was primarily interacting with the H II region around the progenitor. Since then, the X-ray emission has been increasingly dominated by narrower components as the BW encounters dense equatorial ring (ER) material. Even so, continuing v-b emission is seen in the grating spectra suggesting that the interaction with H II region material is ongoing. Based on the deep HETG 2007 and 2011 data sets, and confirmed by RGS and other HETG observations, the v-b component has a width of 9300 {+-} 2000 km s{sup -1} FWHM and contributes of order 20% of the current 0.5-2 keV flux. Guided by this result, SN 1987A's X-ray spectra are modeled as the weighted sum of the non-equilibrium-ionization emission from two simple one-dimensional hydrodynamic simulations; this '2 Multiplication-Sign 1D' model reproduces the observed radii, light curves, and spectra with a minimum of free parameters. The interaction with the H II region ({rho}{sub init} Almost-Equal-To 130 amu cm{sup -3}, {+-} 15 Degree-Sign opening angle) produces the very broad emission lines and most of the 3-10 keV flux. Our ER hydrodynamics, admittedly a crude approximation to the multi-D reality, gives ER densities of {approx}10{sup 4} amu cm{sup -3}, requires dense clumps ( Multiplication-Sign 5.5 density enhancement in {approx}30% of the volume), and predicts that the 0.5-2 keV flux will drop at a rate of {approx}17% per year once no new dense ER material is being shocked.

RELATIVISTIC PLASMA AS THE DOMINANT SOURCE OF THE OPTICAL CONTINUUM EMISSION IN THE BROAD-LINE RADIO GALAXY 3C 120

International Nuclear Information System (INIS)

Leon-Tavares, J.; Lobanov, A. P.; Arshakian, T. G.; Chavushyan, V. H.; Doroshenko, V. T.; Sergeev, S. G.; Efimov, Y. S.; Nazarov, S. V.

2010-01-01

We report a relation between radio emission in the inner jet of the Seyfert galaxy 3C 120 and optical continuum emission in this galaxy. Combining the optical variability data with multi-epoch high-resolution very long baseline interferometry observations reveals that an optical flare rises when a superluminal component emerges into the jet, and its maxima is related to the passage of such component through the location of a stationary feature at a distance of ∼1.3 pc from the jet origin. This indicates that a significant fraction of the optical continuum produced in 3C 120 is non-thermal, and it can ionize material in a sub-relativistic wind or outflow. We discuss implications of this finding for the ionization and structure of the broad emission line region, as well as for the use of broad emission lines for determining black hole masses in radio-loud active galactic nucleus.

DISCOVERY OF BROAD MOLECULAR LINES AND OF SHOCKED MOLECULAR HYDROGEN FROM THE SUPERNOVA REMNANT G357.7+0.3: HHSMT, APEX, SPITZER , AND SOFIA OBSERVATIONS

Energy Technology Data Exchange (ETDEWEB)

Rho, J. [SETI Institute, 189 N. Bernardo Ave., Mountain View, CA 94043 (United States); Hewitt, J. W. [CRESST/University of Maryland, Baltimore County, Baltimore, MD 21250 and NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Bieging, J. [Steward Observatory, The University of Arizona, Tucson AZ 85721 (United States); Reach, W. T. [Universities Space Research Association, SOFIA Science Center, NASA Ames Research Center, MS 232, Moffett Field, CA 94034 (United States); Andersen, M. [Gemini Observatory, Casilla 603, La Serena (Chile); Güsten, R., E-mail: jrho@seti.org, E-mail: john.w.hewitt@unf.edu, E-mail: jbieging@as.arizona.edu, E-mail: wreach@sofia.usra.edu, E-mail: manderse@gemini.edu, E-mail: guesten@mpifr-bonn.mpg.de [Max Planck Institut für Radioastronomie, Auf dem Hugel 69, D-53121 Bonn (Germany)

2017-01-01

We report a discovery of shocked gas from the supernova remnant (SNR) G357.7+0.3. Our millimeter and submillimeter observations reveal broad molecular lines of CO(2-1), CO(3-2), CO(4-3), {sup 13}CO (2-1), and {sup 13}CO (3-2), HCO{sup +}, and HCN using the Heinrich Hertz Submillimeter Telescope, the Arizona 12 m Telescope, APEX, and the MOPRA Telescope. The widths of the broad lines are 15–30 km s{sup −1}, and the detection of such broad lines is unambiguous, dynamic evidence showing that the SNR G357.7+0.3 is interacting with molecular clouds. The broad lines appear in extended regions (>4.′5 × 5′). We also present the detection of shocked H{sub 2} emission in the mid-infrared but lacking ionic lines using Spitzer /IRS observations to map a few-arcminute area. The H{sub 2} excitation diagram shows a best fit with a two-temperature local thermal equilibrium model with the temperatures of ∼200 and 660 K. We observed [C ii] at 158 μ m and high- J CO(11-10) with the German Receiver for Astronomy at Terahertz Frequencies (GREAT) on the Stratospheric Observatory for Infrared Astronomy. The GREAT spectrum of [C ii], a 3 σ detection, shows a broad line profile with a width of 15.7 km{sup −1} that is similar to those of broad CO molecular lines. The line width of [C ii] implies that ionic lines can come from a low-velocity C-shock. Comparison of H{sub 2} emission with shock models shows that a combination of two C-shock models is favored over a combination of C- and J-shocks or a single shock. We estimate the CO density, column density, and temperature using a RADEX model. The best-fit model with n (H{sub 2}) = 1.7 × 10{sup 4} cm{sup −3}, N(CO) = 5.6 × 10{sup 16} cm{sup −2}, and T  = 75 K can reproduce the observed millimeter CO brightnesses.

The size of the narrow-line-emitting region in the Seyfert 1 galaxy NGC 5548 from emission-line variability

International Nuclear Information System (INIS)

Peterson, B. M.; Denney, K. D.; De Rosa, G.; Grier, C. J.; Pogge, R. W.; Kochanek, C. S.; Bentz, M. C.; Vestergaard, M.; Kilerci-Eser, E.; G. Galilei, Università di Padova, Vicolo dell'Osservatorio 3 I-35122, Padova (Italy))" data-affiliation=" (Dipartimento di Fisica e Astronomia G. Galilei, Università di Padova, Vicolo dell'Osservatorio 3 I-35122, Padova (Italy))" >Dalla Bontà, E.; G. Galilei, Università di Padova, Vicolo dell'Osservatorio 3 I-35122, Padova (Italy))" data-affiliation=" (Dipartimento di Fisica e Astronomia G. Galilei, Università di Padova, Vicolo dell'Osservatorio 3 I-35122, Padova (Italy))" >Ciroi, S.

2013-01-01

The narrow [O III] λλ4959, 5007 emission-line fluxes in the spectrum of the well-studied Seyfert 1 galaxy NGC 5548 are shown to vary with time. From this we show that the narrow-line-emitting region has a radius of only 1-3 pc and is denser (n e ∼ 10 5 cm –3 ) than previously supposed. The [O III] line width is consistent with virial motions at this radius given previous determinations of the black hole mass. Since the [O III] emission-line flux is usually assumed to be constant and is therefore used to calibrate spectroscopic monitoring data, the variability has ramifications for the long-term secular variations of continuum and emission-line fluxes, though it has no effect on shorter-term reverberation studies. We present corrected optical continuum and broad Hβ emission-line light curves for the period 1988-2008.

The size of the narrow-line-emitting region in the Seyfert 1 galaxy NGC 5548 from emission-line variability

Energy Technology Data Exchange (ETDEWEB)

Peterson, B. M.; Denney, K. D.; De Rosa, G.; Grier, C. J.; Pogge, R. W.; Kochanek, C. S. [Department of Astronomy, The Ohio State University, 140 W 18th Avenue, Columbus, OH 43210 (United States); Bentz, M. C. [Department of Physics and Astronomy, Georgia State University, 25 Park Place, Suite 610, Atlanta, GA 30303 (United States); Vestergaard, M.; Kilerci-Eser, E. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Dalla Bontà, E.; Ciroi, S. [Dipartimento di Fisica e Astronomia " G. Galilei," Università di Padova, Vicolo dell' Osservatorio 3 I-35122, Padova (Italy)

2013-12-20

The narrow [O III] λλ4959, 5007 emission-line fluxes in the spectrum of the well-studied Seyfert 1 galaxy NGC 5548 are shown to vary with time. From this we show that the narrow-line-emitting region has a radius of only 1-3 pc and is denser (n {sub e} ∼ 10{sup 5} cm{sup –3}) than previously supposed. The [O III] line width is consistent with virial motions at this radius given previous determinations of the black hole mass. Since the [O III] emission-line flux is usually assumed to be constant and is therefore used to calibrate spectroscopic monitoring data, the variability has ramifications for the long-term secular variations of continuum and emission-line fluxes, though it has no effect on shorter-term reverberation studies. We present corrected optical continuum and broad Hβ emission-line light curves for the period 1988-2008.

Line profile variations in selected Seyfert galaxies

International Nuclear Information System (INIS)

Kollatschny, W; Zetzl, M; Ulbrich, K

2010-01-01

Continua as well as the broad emission lines in Seyfert 1 galaxies vary in different galaxies with different amplitudes on typical timescales of days to years. We present the results of two independent variability campaigns taken with the Hobby-Eberly Telescope. We studied in detail the integrated line and continuum variations in the optical spectra of the narrow-line Seyfert galaxy Mrk 110 and the very broad-line Seyfert galaxy Mrk 926. The broad-line emitting region in Mrk 110 has radii of four to 33 light-days as a function of the ionization degree of the emission lines. The line-profile variations are matched by Keplerian disk models with some accretion disk wind. The broad-line region in Mrk 926 is very small showing an extension of two to three light-days only. We could detect a structure in the rms line-profiles as well as in the response of the line profile segments of Mrk 926 indicating the BLR is structured.

Radio ejection and broad forbidden emission lines in the Seyfert galaxy NGC 7674

International Nuclear Information System (INIS)

Unger, S.W.; Pedlar, A.; Axon, D.J.

1988-01-01

The Seyfert nucleus in NGC7674 (Mkn533) is remarkable for its broad asymmetric forbidden line profiles, which extend 2000 kms -1 blueward of the systemic velocity. The galaxy also has a compact nuclear radio source. We have obtained new high-resolution radio observations of NGC7674, using the European VLBI network and the VLA, and optical spectroscopic observations using the Isaac Newton Telescope. The radio maps reveal a triple radio source with a total angular extent of about 0.7 arcsec, and provide evidence that the radio emission is powered by collimated ejection. In the plane of the sky, the ejection axis appears roughly perpendicular to the galactic rotation axis. Although the dominant radio components are separated by 0.5 arcsec, the broad [OIII]λ5007 line emission is confined to within about 0.25 arcsec of the continuum nucleus. (author)

THE COMPLEX CIRCUMNUCLEAR ENVIRONMENT OF THE BROAD-LINE RADIO GALAXY 3C 390.3 REVEALED BY CHANDRA HETG

Energy Technology Data Exchange (ETDEWEB)

Tombesi, F.; Kallman, T.; Leutenegger, M. A. [X-ray Astrophysics Laboratory, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Reeves, J. N. [Center for Space Science and Technology, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States); Reynolds, C. S.; Mushotzky, R. F.; Behar, E. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Braito, V. [INAF—Osservatorio Astronomico di Brera, Via Bianchi 46, I-23807 Merate (Italy); Cappi, M., E-mail: francesco.tombesi@nasa.gov, E-mail: ftombesi@astro.umd.edu [Department of Physics, Technion 32000, Haifa 32000 (Israel)

2016-10-20

We present the first high spectral resolution X-ray observation of the broad-line radio galaxy 3C 390.3 obtained with the high-energy transmission grating spectrometer on board the Chandra X-ray Observatory . The spectrum shows complex emission and absorption features in both the soft X-rays and Fe K band. We detect emission and absorption lines in the energy range E = 700–1000 eV associated with ionized Fe L transitions (Fe XVII–XX). An emission line at the energy of E ≃ 6.4 keV consistent with the Fe K α is also observed. Our best-fit model requires at least three different components: (i) a hot emission component likely associated with the hot interstellar medium in this elliptical galaxy with temperature kT = 0.5 ± 0.1 keV; (ii) a warm absorber with ionization parameter log ξ = 2.3 ± 0.5 erg s{sup −1} cm, column density log N {sub H} = 20.7 ± 0.1 cm{sup −2}, and outflow velocity v {sub out} < 150 km s{sup −1}; and (iii) a lowly ionized reflection component in the Fe K band likely associated with the optical broad-line region or the outer accretion disk. These evidences suggest the possibility that we are looking directly down the ionization cone of this active galaxy and that the central X-ray source only photoionizes along the unobscured cone. This is overall consistent with the angle-dependent unified picture of active galactic nuclei.

THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: RAPID C iv BROAD ABSORPTION LINE VARIABILITY

International Nuclear Information System (INIS)

Grier, C. J.; Brandt, W. N.; Trump, J. R.; Schneider, D. P.; Hall, P. B.; Shen, Yue; Vivek, M.; Dawson, K. S.; Ak, N. Filiz; Chen, Yuguang; Denney, K. D.; Kochanek, C. S.; Peterson, B. M.; Green, Paul J.; Jiang, Linhua; McGreer, Ian D.; Pâris, I.; Tao, Charling; Wood-Vasey, W. M.; Bizyaev, Dmitry

2015-01-01

We report the discovery of rapid variations of a high-velocity C iv broad absorption line trough in the quasar SDSS J141007.74+541203.3. This object was intensively observed in 2014 as a part of the Sloan Digital Sky Survey Reverberation Mapping Project, during which 32 epochs of spectroscopy were obtained with the Baryon Oscillation Spectroscopic Survey spectrograph. We observe significant (>4σ) variability in the equivalent width (EW) of the broad (∼4000 km s −1 wide) C iv trough on rest-frame timescales as short as 1.20 days (∼29 hr), the shortest broad absorption line variability timescale yet reported. The EW varied by ∼10% on these short timescales, and by about a factor of two over the duration of the campaign. We evaluate several potential causes of the variability, concluding that the most likely cause is a rapid response to changes in the incident ionizing continuum. If the outflow is at a radius where the recombination rate is higher than the ionization rate, the timescale of variability places a lower limit on the density of the absorbing gas of n e ≳ 3.9 × 10 5 cm −3 . The broad absorption line variability characteristics of this quasar are consistent with those observed in previous studies of quasars, indicating that such short-term variability may in fact be common and thus can be used to learn about outflow characteristics and contributions to quasar/host-galaxy feedback scenarios

DETERMINING QUASAR BLACK HOLE MASS FUNCTIONS FROM THEIR BROAD EMISSION LINES: APPLICATION TO THE BRIGHT QUASAR SURVEY

International Nuclear Information System (INIS)

Kelly, Brandon C.; Fan Xiaohui; Vestergaard, Marianne

2009-01-01

We describe a Bayesian approach to estimating quasar black hole mass functions (BHMF) using the broad emission lines to estimate black hole mass. We show how using the broad-line mass estimates in combination with statistical techniques developed for luminosity function estimation (e.g., the 1/V a correction) leads to statistically biased results. We derive the likelihood function for the BHMF based on the broad-line mass estimates, and derive the posterior distribution for the BHMF, given the observed data. We develop our statistical approach for a flexible model where the BHMF is modeled as a mixture of Gaussian functions. Statistical inference is performed using Markov chain Monte Carlo (MCMC) methods, and we describe a Metropolis-Hastings algorithm to perform the MCMC. The MCMC simulates random draws from the probability distribution of the BHMF parameters, given the data, and we use a simulated data set to show how these random draws may be used to estimate the probability distribution for the BHMF. In addition, we show how the MCMC output may be used to estimate the probability distribution of any quantities derived from the BHMF, such as the peak in the space density of quasars. Our method has the advantage that it is able to constrain the BHMF even beyond the survey detection limits at the adopted confidence level, accounts for measurement errors and the intrinsic uncertainty in broad-line mass estimates, and provides a natural way of estimating the probability distribution of any quantities derived from the BHMF. We conclude by using our method to estimate the local active BHMF using the z BH ∼> 10 8 M sun . Our analysis implies that at a given M BH , z < 0.5 broad-line quasars have a typical Eddington ratio of ∼0.4 and a dispersion in Eddington ratio of ∼<0.5 dex.

EXTREMELY BROAD RADIO RECOMBINATION MASER LINES TOWARD THE HIGH-VELOCITY IONIZED JET IN CEPHEUS A HW2

International Nuclear Information System (INIS)

Jimenez-Serra, I.; Patel, N.; Martin-Pintado, J.; Baez-Rubio, A.; Thum, C.

2011-01-01

We present the first detection of the H40α, H34α, and H31α radio recombination lines (RRLs) at millimeter wavelengths toward the high-velocity ionized jet in the Cepheus A HW2 star-forming region. From our single-dish and interferometric observations, we find that the measured RRLs show extremely broad asymmetric line profiles with zero-intensity line widths of ∼1100 km s -1 . From the line widths, we estimate a terminal velocity for the ionized gas in the jet of ≥500 km s -1 , consistent with that obtained from the proper motions of the HW2 radio jet. The total integrated line-to-continuum flux ratios of the H40α, H34α, and H31α lines are 43, 229, and 280 km s -1 , clearly deviating from LTE predictions. These ratios are very similar to those observed for the RRL masers toward MWC349A, suggesting that the intensities of the RRLs toward HW2 are affected by maser emission. Our radiative transfer modeling of the RRLs shows that their asymmetric profiles could be explained by maser emission arising from a bi-conical radio jet with a semi-opening angle of 18 deg., electron density distribution varying as r -2.11 , and turbulent and expanding wind velocities of 60 and 500 km s -1 .

THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: RAPID C iv BROAD ABSORPTION LINE VARIABILITY

Energy Technology Data Exchange (ETDEWEB)

Grier, C. J.; Brandt, W. N.; Trump, J. R.; Schneider, D. P. [Department of Astronomy and Astrophysics and Institute for Gravitation and the Cosmos, The Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, Toronto, ON M3J 1P3 (Canada); Shen, Yue [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Vivek, M.; Dawson, K. S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Ak, N. Filiz [Faculty of Sciences, Department of Astronomy and Space Sciences, Erciyes University, 38039 Kayseri (Turkey); Chen, Yuguang [Department of Astronomy, School of Physics, Peking University, Beijing 100871 (China); Denney, K. D.; Kochanek, C. S.; Peterson, B. M. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Green, Paul J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Jiang, Linhua [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); McGreer, Ian D. [Steward Observatory, The University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Pâris, I. [INAF-Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, I-34131 Trieste (Italy); Tao, Charling [Centre de Physique des Particules de Marseille, Aix-Marseille Universite, CNRS /IN2P3, 163, avenue de Luminy, Case 902, F-13288 Marseille Cedex 09 (France); Wood-Vasey, W. M. [PITT PACC, Department of Physics and Astronomy, University of Pittsburgh, 3941 O’Hara Street, Pittsburgh, PA 15260 (United States); Bizyaev, Dmitry, E-mail: grier@psu.edu [Apache Point Observatory and New Mexico State University, P.O. Box 59, Sunspot, NM, 88349-0059 (United States); and others

2015-06-10

We report the discovery of rapid variations of a high-velocity C iv broad absorption line trough in the quasar SDSS J141007.74+541203.3. This object was intensively observed in 2014 as a part of the Sloan Digital Sky Survey Reverberation Mapping Project, during which 32 epochs of spectroscopy were obtained with the Baryon Oscillation Spectroscopic Survey spectrograph. We observe significant (>4σ) variability in the equivalent width (EW) of the broad (∼4000 km s{sup −1} wide) C iv trough on rest-frame timescales as short as 1.20 days (∼29 hr), the shortest broad absorption line variability timescale yet reported. The EW varied by ∼10% on these short timescales, and by about a factor of two over the duration of the campaign. We evaluate several potential causes of the variability, concluding that the most likely cause is a rapid response to changes in the incident ionizing continuum. If the outflow is at a radius where the recombination rate is higher than the ionization rate, the timescale of variability places a lower limit on the density of the absorbing gas of n{sub e} ≳ 3.9 × 10{sup 5} cm{sup −3}. The broad absorption line variability characteristics of this quasar are consistent with those observed in previous studies of quasars, indicating that such short-term variability may in fact be common and thus can be used to learn about outflow characteristics and contributions to quasar/host-galaxy feedback scenarios.

Discovery of an X-ray Violently Variable Broad Absorption Line Quasar

Science.gov (United States)

Ghosh, Kajal K.; Gutierrez, Carlos M.; Punsly, Brian; Chevallier, Loic; Goncalves, Anabela C.

2006-01-01

In this letter, we report on a quasar that is violently variable in the X-rays, XVV. It is also a broad absorption line quasar (BALQSO) that exhibits both high ionization and low ionization UV absorption lines (LoBALQSO). It is very luminous in the X-rays (approximately 10(exp 46) ergs s(sup -l) over the entire X-ray band). Surprisingly, this does not over ionize the LoBAL outflow. The X-rays vary by a factor of two within minutes in the quasar rest frame, which is shorter than 1/30 of the light travel time across a scale length equal to the black hole radius. We concluded that the X-rays are produced in a relativistic jet beamed toward earth in which variations in the Doppler enhancement produce the XVV behavior.

Application of the spine-layer jet radiation model to outbursts in the broad-line radio galaxy 3C 120

Science.gov (United States)

Janiak, M.; Sikora, M.; Moderski, R.

2016-05-01

We present a detailed Fermi/LAT data analysis for the broad-line radio galaxy 3C 120. This source has recently entered into a state of increased γ-ray activity which manifested itself in two major flares detected by Fermi/LAT in 2014 September and 2015 April with no significant flux changes reported in other wavelengths. We analyse available data focusing our attention on aforementioned outbursts. We find very fast variability time-scale during flares (of the order of hours) together with a significant γ-ray flux increase. We show that the ˜6.8 yr averaged γ-ray emission of 3C 120 is likely a sum of the external radiation Compton and the synchrotron self-Compton radiative components. To address the problem of violent γ-ray flares and fast variability we model the jet radiation dividing the jet structure into two components: the wide and relatively slow outer layer and the fast, narrow spine. We show that with the addition of the fast spine occasionally bent towards the observer we are able to explain observed spectral energy distribution of 3C 120 during flares with the Compton upscattered broad-line region and dusty torus photons as main γ-rays emission mechanism.

Outflow and hot dust emission in broad absorption line quasars

Energy Technology Data Exchange (ETDEWEB)

Zhang, Shaohua; Zhou, Hongyan [Polar Research Institute of China, 451 Jinqiao Road, Shanghai 200136 (China); Wang, Huiyuan; Wang, Tinggui; Xing, Feijun; Jiang, Peng [Key Laboratory for Research in Galaxies and Cosmology, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, Anhui 230026 (China); Zhang, Kai, E-mail: zhangshaohua@pric.gov.cn, E-mail: whywang@mail.ustc.edu.cn [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China)

2014-05-01

We have investigated a sample of 2099 broad absorption line (BAL) quasars with z = 1.7-2.2 built from the Sloan Digital Sky Survey Data Release Seven and the Wide-field Infrared Survey. This sample is collected from two BAL quasar samples in the literature and is refined by our new algorithm. Correlations of outflow velocity and strength with a hot dust indicator (β{sub NIR}) and other quasar physical parameters—such as an Eddington ratio, luminosity, and a UV continuum slope—are explored in order to figure out which parameters drive outflows. Here β{sub NIR} is the near-infrared continuum slope, which is a good indicator of the amount of hot dust emission relative to the accretion disk emission. We confirm previous findings that outflow properties moderately or weakly depend on the Eddington ratio, UV slope, and luminosity. For the first time, we report moderate and significant correlations of outflow strength and velocity with β{sub NIR} in BAL quasars. It is consistent with the behavior of blueshifted broad emission lines in non-BAL quasars. The statistical analysis and composite spectra study both reveal that outflow strength and velocity are more strongly correlated with β{sub NIR} than the Eddington ratio, luminosity, and UV slope. In particular, the composites show that the entire C IV absorption profile shifts blueward and broadens as β{sub NIR} increases, while the Eddington ratio and UV slope only affect the high and low velocity part of outflows, respectively. We discuss several potential processes and suggest that the dusty outflow scenario, i.e., that dust is intrinsic to outflows and may contribute to the outflow acceleration, is most likely.

EMISSION SIGNATURES FROM SUB-PARSEC BINARY SUPERMASSIVE BLACK HOLES. I. DIAGNOSTIC POWER OF BROAD EMISSION LINES

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Khai; Bogdanović, Tamara [Center for Relativistic Astrophysics, School of Physics, Georgia Institute of Technology, Atlanta GA 30332 (United States)

2016-09-10

Motivated by advances in observational searches for sub-parsec supermassive black hole binaries (SBHBs) made in the past few years, we develop a semi-analytic model to describe spectral emission-line signatures of these systems. The goal of this study is to aid the interpretation of spectroscopic searches for binaries and to help test one of the leading models of binary accretion flows in the literature: SBHB in a circumbinary disk. In this work, we present the methodology and a comparison of the preliminary model with the data. We model SBHB accretion flows as a set of three accretion disks: two mini-disks that are gravitationally bound to the individual black holes and a circumbinary disk. Given a physically motivated parameter space occupied by sub-parsec SBHBs, we calculate a synthetic database of nearly 15 million broad optical emission-line profiles and explore the dependence of the profile shapes on characteristic properties of SBHBs. We find that the modeled profiles show distinct statistical properties as a function of the semimajor axis, mass ratio, eccentricity of the binary, and the degree of alignment of the triple disk system. This suggests that the broad emission-line profiles from SBHB systems can in principle be used to infer the distribution of these parameters and as such merit further investigation. Calculated profiles are more morphologically heterogeneous than the broad emission lines in observed SBHB candidates and we discuss improved treatment of radiative transfer effects, which will allow a direct statistical comparison of the two groups.

EMISSION SIGNATURES FROM SUB-PARSEC BINARY SUPERMASSIVE BLACK HOLES. I. DIAGNOSTIC POWER OF BROAD EMISSION LINES

International Nuclear Information System (INIS)

Nguyen, Khai; Bogdanović, Tamara

2016-01-01

Motivated by advances in observational searches for sub-parsec supermassive black hole binaries (SBHBs) made in the past few years, we develop a semi-analytic model to describe spectral emission-line signatures of these systems. The goal of this study is to aid the interpretation of spectroscopic searches for binaries and to help test one of the leading models of binary accretion flows in the literature: SBHB in a circumbinary disk. In this work, we present the methodology and a comparison of the preliminary model with the data. We model SBHB accretion flows as a set of three accretion disks: two mini-disks that are gravitationally bound to the individual black holes and a circumbinary disk. Given a physically motivated parameter space occupied by sub-parsec SBHBs, we calculate a synthetic database of nearly 15 million broad optical emission-line profiles and explore the dependence of the profile shapes on characteristic properties of SBHBs. We find that the modeled profiles show distinct statistical properties as a function of the semimajor axis, mass ratio, eccentricity of the binary, and the degree of alignment of the triple disk system. This suggests that the broad emission-line profiles from SBHB systems can in principle be used to infer the distribution of these parameters and as such merit further investigation. Calculated profiles are more morphologically heterogeneous than the broad emission lines in observed SBHB candidates and we discuss improved treatment of radiative transfer effects, which will allow a direct statistical comparison of the two groups.

Formation of broad Balmer wings in symbiotic stars

International Nuclear Information System (INIS)

Chang, Seok-Jun; Heo, Jeong-Eun; Hong, Chae-Lin; Lee, Hee-Won

2016-01-01

Symbiotic stars are binary systems composed of a hot white dwarf and a mass losing giant. In addition to many prominent emission lines symbiotic stars exhibit Raman scattered O VI features at 6825 and 7088 Å. Another notable feature present in the spectra of many symbiotics is the broad wings around Balmer lines. Astrophysical mechanisms that can produce broad wings include Thomson scattering by free electrons and Raman scattering of Ly,β and higher series by neutral hydrogen. In this poster presentation we produce broad wings around Hα and H,β adopting a Monte Carlo techinique in order to make a quantitative comparison of these two mechanisms. Thomson wings are characterized by the exponential cutoff given by the termal width whereas the Raman wings are dependent on the column density and continuum shape in the far UV region. A brief discussion is provided. (paper)

Narrow absorption lines complex I: one form of broad absorption line

Science.gov (United States)

Lu, Wei-Jian; Lin, Ying-Ru

2018-03-01

We discover that some of the broad absorption lines (BALs) are actually a complex of narrow absorption lines (NALs). As a pilot study of this type of BAL, we show this discovery through a typical example in this paper. Utilizing the two-epoch observations of J002710.06-094435.3 (hereafter J0027-0944) from the Sloan Digital Sky Survey (SDSS), we find that each of the C IV and Si IV BAL troughs contains at least four NAL doublets. By resolving the Si IV BAL into multiple NALs, we present the following main results and conclusions. First, all these NALs show coordinated variations between the two-epoch SDSS observations, suggesting that they all originate in the quasar outflow, and that their variations are due to global changes in the ionization condition of the absorbing gas. Secondly, a BAL consisting of a number of NAL components indicates that this type of BAL is basically the same as the intrinsic NAL, which tends to support the inclination model rather than the evolution model. Thirdly, although both the C IV and Si IV BALs originate from the same clumpy substructures of the outflow, they show different profile shapes: multiple absorption troughs for the Si IV BAL in a wider velocity range, while P-Cygni for the C IV BAL in a narrower velocity range. This can be interpreted by the substantial differences in fine structure and oscillator strength between the Si IVλλ1393, 1402 and C IVλλ1548, 1551 doublets. Based on the above conclusions, we consider that the decomposition of a BAL into NALs can serve as a way to resolve the clumpy structure for outflows, and it can be used to learn more about characteristics of the clumpy structure and to test the outflow model, when utilizing high-resolution spectra and photoionization model.

The near-infrared broad emission line region of active galactic nuclei - II. The 1-μm continuum

Science.gov (United States)

Landt, Hermine; Elvis, Martin; Ward, Martin J.; Bentz, Misty C.; Korista, Kirk T.; Karovska, Margarita

2011-06-01

We use quasi-simultaneous near-infrared (near-IR) and optical spectroscopy from four observing runs to study the continuum around 1 μm in 23 well-known broad emission line active galactic nuclei (AGN). We show that, after correcting the optical spectra for host galaxy light, the AGN continuum around this wavelength can be approximated by the sum of mainly two emission components, a hot dust blackbody and an accretion disc. The accretion disc spectrum appears to dominate the flux at ˜ 1 μm, which allows us to derive a relation for estimating AGN black hole masses based on the near-IR virial product. This result also means that a near-IR reverberation programme can determine the AGN state independent of simultaneous optical spectroscopy. On average we derive hot dust blackbody temperatures of ˜1400 K, a value close to the sublimation temperature of silicate dust grains, and relatively low hot dust covering factors of ˜7 per cent. Our preliminary variability studies indicate that in most sources, the hot dust emission responds to changes in the accretion disc flux with the expected time lag; however, a few sources show a behaviour that can be attributed to dust destruction.

Genetic analysis of a novel broad-spectrum powdery mildew resistance gene from the wheat-Agropyron cristatum introgression line Pubing 74.

Science.gov (United States)

Lu, Yuqing; Yao, Miaomiao; Zhang, Jinpeng; Song, Liqiang; Liu, Weihua; Yang, Xinming; Li, Xiuquan; Li, Lihui

2016-09-01

A novel broad-spectrum powdery mildew resistance gene PmPB74 was identified in wheat- Agropyron cristatum introgression line Pubing 74. Development of wheat cultivars with broad-spectrum, durable resistance to powdery mildew has been restricted by lack of superior genetic resources. In this study, a wheat-A. cristatum introgression line Pubing 74, originally selected from a wide cross between the common wheat cultivar Fukuhokomugi (Fukuho) and Agropyron cristatum (L.) Gaertn (2n = 4x = 28; genome PPPP), displayed resistance to powdery mildew at both the seedling and adult stages. The putative alien chromosomal fragment in Pubing 74 was below the detection limit of genomic in situ hybridization (GISH), but evidence for other non-GISH-detectable introgressions was provided by the presence of three STS markers specific to A. cristatum. Genetic analysis indicated that Pubing 74 carried a single dominant gene for powdery mildew resistance, temporarily designated PmPB74. Molecular mapping showed that PmPB74 was located on wheat chromosome arm 5DS, and flanked by markers Xcfd81 and HRM02 at genetic distances of 2.5 and 1.7 cM, respectively. Compared with other lines with powdery mildew resistance gene(s) on wheat chromosome arm 5DS, Pubing 74 was resistant to all 28 Blumeria graminis f. sp tritici (Bgt) isolates from different wheat-producing regions of northern China. Allelism tests indicated that PmPB74 was not allelic to PmPB3558 or Pm2. Our work showed that PmPB74 is a novel gene with broad resistance to powdery mildew, and hence will be helpful in broadening the genetic basis of powdery mildew resistance in wheat.

The emission-line regions in the nucleus of NGC 1313 probed with GMOS-IFU: a supergiant/hypergiant candidate and a kinematically cold nucleus

Science.gov (United States)

Menezes, R. B.; Steiner, J. E.

2017-04-01

NGC 1313 is a bulgeless nearby galaxy, classified as SB(s)d. Its proximity allows high spatial resolution observations. We performed the first detailed analysis of the emission-line properties in the nuclear region of NGC 1313, using an optical data cube obtained with the Gemini Multi-object Spectrograph. We detected four main emitting areas, three of them (regions 1, 2 and 3) having spectra typical of H II regions. Region 1 is located very close to the stellar nucleus and shows broad spectral features characteristic of Wolf-Rayet stars. Our analysis revealed the presence of one or two WC4-5 stars in this region, which is compatible with results obtained by previous studies. Region 4 shows spectral features (as a strong Hα emission line, with a broad component) typical of a massive emission-line star, such as a luminous blue variable, a B[e] supergiant or a B hypergiant. The radial velocity map of the ionized gas shows a pattern consistent with rotation. A significant drop in the values of the gas velocity dispersion was detected very close to region 1, which suggests that the young stars there were formed from this cold gas, possibly keeping low values of velocity dispersion. Therefore, although detailed measurements of the stellar kinematics were not possible (due to the weak stellar absorption spectrum of this galaxy), we predict that NGC 1313 may also show a drop in the values of the stellar velocity dispersion in its nuclear region.

VT Biodiversity Project - Biophysical Regions boundary lines

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This dataset divides Vermont into eight sub-regions on the basis of bedrock geology, gross physiography, climate, and broad-scale patterns of...

NuSTAR reveals an intrinsically x-ray weak broad absorption line quasar in the ultraluminous infrared galaxy Markarian 231

DEFF Research Database (Denmark)

Teng, Stacy H.; Brandt, W. N.; Harrison, F. A.

2014-01-01

-ionization broad absorption line quasar that is intrinsically X-ray weak. The weak ionizing continuum may explain the lack of mid-infrared [O IV], [Ne V], and [Ne VI] fine-structure emission lines which are present in sources with otherwise similar AGN properties. We argue that the intrinsic X-ray weakness may...

Marketing the `Broad Line': Invitations to STEM education in a Swedish recruitment campaign

Science.gov (United States)

Andrée, Maria; Hansson, Lena

2013-01-01

In many Western societies, there is a concern about the tendency of young people not choosing Science, Technology, Engineering, and Mathematics (STEM) education and occupations. In response, different initiatives have been launched. If one believes that science should have a place in more young people's lives, an important question is to what extent recruitment campaigns communicate messages that open up for STEM education to become relevant in young people's identity formation. Here, we analyse a Swedish government-initiated, primarily Internet-based recruitment attempt ('The Broad Line Campaign') aimed at increasing the number of young people choosing the natural science programme in upper secondary school. The campaign is based on marketing principles and deliberately draws on identity issues. The data analysed consists of campaign films and written resources describing the campaign. Data are analysed by use of the constant comparative approach in order to produce categories describing different messages about why to engage in STEM education. These messages are then analysed from an identity perspective using the concept of subjective values. Our results show that the messages communicated in the Broad Line campaign emphasise utility value, attainment value and relative cost rather than interest-enjoyment. The campaign communicates that the natural science programme is to be associated with a high attainment value without establishing relations to the field of science. Finally, potential consequences of the communicated messages in the campaign are discussed in light of previous research.

MULTIWAVELENGTH VARIABILITY OF THE BROAD LINE RADIO GALAXY 3C 120

International Nuclear Information System (INIS)

Marshall, Kevin; Ryle, Wesley T.; Miller, H. Richard; Marscher, Alan P.; Jorstad, Svetlana G.; Chicka, Benjamin; McHardy, Ian M.

2009-01-01

We present results from a multiyear monitoring campaign of the broad-line radio galaxy 3C 120, using the Rossi X-ray Timing Explorer for nearly five years of observations. Additionally, we present coincident optical monitoring using data from several ground-based observatories. Both the X-ray and optical emission are highly variable and appear to be strongly correlated, with the X-ray emission leading the optical by 28 days. The X-ray power density spectrum is best fit by a broken power law, with a low-frequency slope of -1.2, breaking to a high-frequency slope of -2.1, and a break frequency of log ν b = -5.75 Hz, or 6.5 days. This value agrees well with the value expected based on 3C 120's mass and accretion rate. We find no evidence for a second break in the power spectrum. Combined with a moderately soft X-ray spectrum (Γ = 1.8) and a moderately high accretion rate, this indicates that 3C 120 fits in well with the high/soft variability state found in most other active galactic nuclei. Previous studies have shown that the spectrum has a strong Fe Kα line, which may be relativistically broadened. The presence of this line, combined with a power spectrum similar to that seen in Seyfert galaxies, suggests that the majority of the X-ray emission in this object arises in or near the disk, and not in the jet.

The Of emission lines near 4650 A

International Nuclear Information System (INIS)

Underhill, A.B.; Gilroy, K.K.; Hill, G.M.

1989-01-01

Rectified, normalized, high S/N intensity tracings of nine Of stars were obtained from Reticon spectra in the 4550-4800-A region. The well-known relatively sharp Of emission lines are seen to stand on pedestals of broad weak emission somewhat like the broad emission lines from WR stars. It is suggested that cascades following dielectronic recombination may be an important process driving some lines of N III, C III, and C IV into the emission of Of stars, and that the sharp Of lines come from plasma that is stationary with respect to the star. The broad emission features show an extensive low-density wind from each star. The results imply that the detection of two, more or less equal, broad jumps in the rest spectra of galaxies at about 4640 and 4686 A is more indicative of Of stars than of WR stars. 32 refs

FLARE-LIKE VARIABILITY OF THE Mg II {lambda}2800 EMISSION LINE IN THE {gamma}-RAY BLAZAR 3C 454.3

Energy Technology Data Exchange (ETDEWEB)

Leon-Tavares, J. [Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Vaeisaelaentie 20, FI-21500 Piikkioe (Finland); Chavushyan, V.; Patino-Alvarez, V.; Carraminana, A.; Carrasco, L. [Instituto Nacional de Astrofisica Optica y Electronica (INAOE), Apartado Postal 51 y 216, 72000 Puebla (Mexico); Valtaoja, E. [Tuorla Observatory, Department of Physics and Astronomy, University of Turku, FI-20100 Turku (Finland); Arshakian, T. G. [I. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln (Germany); Popovic, L. C. [Astronomical Observatory, Volgina 7, 11160 Belgrade 74 (Serbia); Tornikoski, M.; Laehteenmaeki, A. [Aalto University Metsaehovi Radio Observatory, Metsaehovintie 114, FI-02540 Kylmaelae (Finland); Lobanov, A. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany)

2013-02-01

We report the detection of a statistically significant flare-like event in the Mg II {lambda}2800 emission line of 3C 454.3 during the outburst of autumn 2010. The highest levels of emission line flux recorded over the monitoring period (2008-2011) coincide with a superluminal jet component traversing through the radio core. This finding crucially links the broad emission line fluctuations to the non-thermal continuum emission produced by relativistically moving material in the jet and hence to the presence of broad-line region clouds surrounding the radio core. If the radio core were located at several parsecs from the central black hole, then our results would suggest the presence of broad-line region material outside the inner parsec where the canonical broad-line region is envisaged to be located. We briefly discuss the implications of broad emission line material ionized by non-thermal continuum in the context of virial black hole mass estimates and gamma-ray production mechanisms.

Broad absorption line symbiotic stars: highly ionized species in the fast outflow from MWC 560

Science.gov (United States)

Lucy, Adrian B.; Knigge, Christian; Sokoloski, J. L.

2018-04-01

In symbiotic binaries, jets and disk winds may be integral to the physics of accretion onto white dwarfs from cool giants. The persistent outflow from symbiotic star MWC 560 (≡V694 Mon) is known to manifest as broad absorption lines (BALs), most prominently at the Balmer transitions. We report the detection of high-ionization BALs from C IV, Si IV, N V, and He II in International Ultraviolet Explorer spectra obtained on 1990 April 29 - 30, when an optical outburst temporarily erased the obscuring `iron curtain' of absorption troughs from Fe II and similar ions. The C IV and Si IV BALs reached maximum radial velocities at least 1000 km s-1 higher than contemporaneous Mg II and He II BALs; the same behaviors occur in the winds of quasars and cataclysmic variables. An iron curtain lifts to unveil high-ionization BALs during the P Cygni phase observed in some novae, suggesting by analogy a temporary switch in MWC 560 from persistent outflow to discrete mass ejection. At least three more symbiotic stars exhibit broad absorption with blue edges faster than 1500 km s-1; high-ionization BALs have been reported in AS 304 (≡V4018 Sgr), while transient Balmer BALs have been reported in Z And and CH Cyg. These BAL-producing fast outflows can have wider opening angles than has been previously supposed. BAL symbiotics are short-timescale laboratories for their giga-scale analogs, broad absorption line quasars (BALQSOs), which display a similarly wide range of ionization states in their winds.

THE INTRINSIC FRACTIONS AND RADIO PROPERTIES OF LOW-IONIZATION BROAD ABSORPTION LINE QUASARS

International Nuclear Information System (INIS)

Dai Xinyu; Shankar, Francesco; Sivakoff, Gregory R.

2012-01-01

Low-ionization (Mg II, Fe II, and Fe III) broad absorption line quasars (LoBALs) probe a relatively obscured quasar population and could be at an early evolutionary stage for quasars. We study the intrinsic fractions of LoBALs using the Sloan Digital Sky Survey (SDSS), Two Micron All Sky Survey, and Faint Images of the Radio Sky at Twenty cm survey. We find that the LoBAL fractions of the near-infrared (NIR) and radio samples are approximately 5-7 times higher than those measured in the optical sample. This suggests that the fractions measured in the NIR and radio bands are closer to the intrinsic fractions of the populations, and that the optical fractions are significantly biased due to obscuration effects, similar to high-ionization broad absorption line quasars (HiBALs). Considering a population of obscured quasars that do not enter the SDSS, which could have a much higher LoBAL fraction, we expect that the intrinsic fraction of LoBALs could be even higher. We also find that the LoBAL fractions decrease with increasing radio luminosities, again, similarly to HiBALs. In addition, we find evidence for increasing fractions of LoBALs toward higher NIR luminosities, especially for FeLoBALs with a fraction of ∼18% at M K s < -31 mag. This population of NIR-luminous LoBALs may be at an early evolutionary stage of quasar evolution. To interpret the data, we use a luminosity-dependent model for LoBALs that yields significantly better fits than those from a pure geometric model.

Broad line and pulsed NMR study of molecular motion in furfuryl alcohol resins

International Nuclear Information System (INIS)

Glowinkowski, S.; Pajak, Z.

1978-01-01

Broad line and pulsed nuclear magnetic resonance studies are carried out on a number of furfuryl alcohol resins differentiated by viscosity. Proton NMR spectra and relaxation times T 1 and Tsub(1rho) are measured over a wide temperature range and the results are interpreted in terms of molecular motion. The marked decrease in second moment and existence of high temperature spin-lattice relaxation times minima are presumed to result from rotational motion of polymer chains. The relaxation processes at low temperature are believed to be due to rotational motion of methyl endgroup and paramagnetic centres. (author)

An optical and near-infrared polarization survey of Seyfert and broad-line radio galaxies. Pt. 2

International Nuclear Information System (INIS)

Brindle, C.; Hough, J.H.; Bailey, J.A.; Axon, D.J.; Ward, M.J.; McLean, I.S.

1990-01-01

We discuss the wavelength dependence (0.44-2.2 μm) of polarization of the sample of 71 Seyfert and three broad-line radio galaxies presented in a previous paper. For four galaxies, 3A 0557-383, Fairall 51, IC 4392A and NGC 3783, we also present spectropolarimetry covering the wavelength range of 0.4-0.6 μm. (author)

Surprises from a Deep ASCA Spectrum of the Broad Absorption Line Quasar PHL 5200

Science.gov (United States)

Mathur, Smita; Matt, G.; Green, P. J.; Elvis, M.; Singh, K. P.

2002-01-01

We present a deep (approx. 85 ks) ASCA observation of the prototype broad absorption line quasar (BALQSO) PHL 5200. This is the best X-ray spectrum of a BALQSO yet. We find the following: (1) The source is not intrinsically X-ray weak. (2) The line-of-sight absorption is very strong, with N(sub H) = 5 x 10(exp 23)/sq cm. (3) The absorber does not cover the source completely; the covering fraction is approx. 90%. This is consistent with the large optical polarization observed in this source, implying multiple lines of sight. The most surprising result of this observation is that (4) the spectrum of this BALQSO is not exactly similar to other radio-quiet quasars. The hard X-ray spectrum of PHL 5200 is steep, with the power-law spectral index alpha approx. 1.5. This is similar to the steepest hard X-ray slopes observed so far. At low redshifts, such steep slopes are observed in narrow-line Seyfert 1 (NLS1) galaxies, believed to be accreting at a high Eddington rate. This observation strengthens the analogy between BALQSOs and NLS1 galaxies and supports the hypothesis that BALQSOs represent an early evolutionary state of quasars. It is well accepted that the orientation to the line of sight determines the appearance of a quasar: age seems to play a significant role as well.

A Revised Broad-line Region Radius and Black Hole Mass for the Narrow-line Seyfert 1 NGC 4051

DEFF Research Database (Denmark)

Denney, K. D.; Watson, L. C.; Peterson, B. M.

2009-01-01

) radius and the optical continuum luminosity—the R BLR-L relationship. Our new measurements of the lag time between variations in the continuum and Hß emission line made from spectroscopic monitoring of NGC 4051 lead to a measured BLR radius of R BLR = 1.87+0.54 -0.50 light days and black hole mass of M...

Extended Emission-Line Regions: Remnants of Quasar Superwinds?

Science.gov (United States)

Fu, Hai; Stockton, Alan

2009-01-01

We give an overview of our recent integral-field-unit spectroscopy of luminous extended emission-line regions (EELRs) around low-redshift quasars, including new observations of five fields. Previous work has shown that the most luminous EELRs are found almost exclusively around steep-spectrum radio-loud quasars, with apparently disordered global velocity fields, and little, if any, morphological correlation with either the host galaxy or the radio structure. Our new observations confirm and expand these results. The EELRs often show some clouds with velocities exceeding 500 km s-1, ranging up to 1100 km s-1, but the velocity dispersions, with few exceptions, are in the 30-100 km s-1 range. Emission-line ratios show that the EELRs are clearly photoionized by the quasars. Masses of the EELRs range up to 1010Msun. Essentially all of the EELRs show relatively low metallicities, and they are associated with quasars that, in contrast to most, show similarly low metallicities in their broad-line regions. The two objects in our sample that do not have classical double-lobed radio morphologies (3C 48, with a compact-steep-spectrum source; Mrk 1014, radio quiet, but with a weak compact-steep-spectrum source) are the only ones that appear to have recent star formation. While some of the less luminous EELRs may have other origins, the most likely explanation for those in our sample is that they are examples of gas swept out of the host galaxy by a large-solid-angle blast wave accompanying the production of the radio jets. The triggering of the quasar activity is almost certainly the result of the merger of a gas-rich galaxy with a massive, gas-poor galaxy hosting the supermassive black hole. Based in part on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the

An optical and near-infrared polarization survey of Seyfert and broad-line radio galaxies. Pt. 1

International Nuclear Information System (INIS)

Brindle, C.; Hough, J.H.; Bailey, J.A.; Axon, D.J.; Ward, M.J.; McLean, I.S.

1990-01-01

We present new broad-band optical and near-infrared (0.44-2.2 μm) flux density and polarization measurements of a sample of 71 Seyfert galaxies and three broad-line radio galaxies. We confirm the results of earlier studies which show that the polarization of Seyferts is generally low in the V-band and at longer wavelengths, but in the B-band somewhat higher polarizations are commonly found. After correction has been made for the effects of stellar dilution, we find that Seyfert 2 nuclei are probably more highly polarized than Seyfert 1's. The small sample of Seyfert 2's selected using the 'warm' IRAS colour criterion tend to be more highly polarised than those selected by optical techniques. (author)

The broad component of hydrogen emission lines in nuclei of Seyfert galaxies: Comments on a charge exchange model

International Nuclear Information System (INIS)

Katz, A.

1975-01-01

A model to account for the broad hydrogen line emission from the nuclei of Seyfert galaxies based on charge exchange and collisional processes, as proposed by Ptak and Stoner, is investigated. The model consists of a source of fast (E approx. 10 5 eV) protons streaming through a medium of quiescent gas. One of the major problems that results from such a model concerns the strong narrow hydrogen line core that would be produced, in direct conflict with the observations. The lines cannot arise from gas arranged throughout a spherical volume surrounding the source of the fast particles because the fast protons would produce far more ionizations than the possible number of recombinations. A very dense shell source of less than 1 AU in thickness and at least several tens of parsecs in radius must be invoked to reproduce the asymmetric broad profiles observed. There must be absorption throughout the center of the shell to account for the line profiles. The gas cannot be arranged in dense clumps throughout a large volume because momentum exchange of the gas with the primary particles would quickly accelerate any clumps. The energy balance and energy requirements of such a model are investigated, and it is found that an energy equal to or greater than the total luminosity of most Seyfert galaxies is required to produce the hydrogen line alone. The gas must be mostly neutral and den []e (N approx. 10 7 ) if a reasonable temperature is to be maintained

Testing Event Discrimination over Broad Regions using the Historical Borovoye Observatory Explosion Dataset

Science.gov (United States)

Pasyanos, Michael E.; Ford, Sean R.; Walter, William R.

2014-03-01

We test the performance of high-frequency regional P/S discriminants to differentiate between earthquakes and explosions at test sites and over broad regions using a historical dataset of explosions recorded at the Borovoye Observatory in Kazakhstan. We compare these explosions to modern recordings of earthquakes at the same location. We then evaluate the separation of the two types of events using the raw measurements and those where the amplitudes are corrected for 1-D and 2-D attenuation structure. We find that high-frequency P/S amplitudes can reliably identify earthquakes and explosions, and that the discriminant is applicable over broad regions as long as propagation effects are properly accounted for. Lateral attenuation corrections provide the largest improvement in the 2-4 Hz band, the use of which may successfully enable the identification of smaller, distant events that have lower signal-to-noise at higher frequencies. We also find variations in P/S ratios among the three main nuclear testing locations within the Semipalatinsk Test Site which, due to their nearly identical paths to BRVK, must be a function of differing geology and emplacement conditions.

THE STRUCTURE OF THE BROAD-LINE REGION IN ACTIVE GALACTIC NUCLEI. I. RECONSTRUCTED VELOCITY-DELAY MAPS

International Nuclear Information System (INIS)

Grier, C. J.; Peterson, B. M.; Pogge, R. W.; De Rosa, G.; Martini, Paul; Kochanek, C. S.; Zu, Y.; Shappee, B.; Beatty, T. G.; Salvo, C. Araya; Bird, J. C.; Horne, Keith; Bentz, M. C.; Denney, K. D.; Siverd, R.; Sergeev, S. G.; Borman, G. A.; Kaspi, S.; Bord, D. J.; Che, X.

2013-01-01

We present velocity-resolved reverberation results for five active galactic nuclei. We recovered velocity-delay maps using the maximum entropy method for four objects: Mrk 335, Mrk 1501, 3C 120, and PG 2130+099. For the fifth, Mrk 6, we were only able to measure mean time delays in different velocity bins of the Hβ emission line. The four velocity-delay maps show unique dynamical signatures for each object. For 3C 120, the Balmer lines show kinematic signatures consistent with both an inclined disk and infalling gas, but the He II λ4686 emission line is suggestive only of inflow. The Balmer lines in Mrk 335, Mrk 1501, and PG 2130+099 show signs of infalling gas, but the He II emission in Mrk 335 is consistent with an inclined disk. We also see tentative evidence of combined virial motion and infalling gas from the velocity-binned analysis of Mrk 6. The maps for 3C 120 and Mrk 335 are two of the most clearly defined velocity-delay maps to date. These maps constitute a large increase in the number of objects for which we have resolved velocity-delay maps and provide evidence supporting the reliability of reverberation-based black hole mass measurements.

THE STRUCTURE OF THE BROAD-LINE REGION IN ACTIVE GALACTIC NUCLEI. I. RECONSTRUCTED VELOCITY-DELAY MAPS

Energy Technology Data Exchange (ETDEWEB)

Grier, C. J.; Peterson, B. M.; Pogge, R. W.; De Rosa, G.; Martini, Paul; Kochanek, C. S.; Zu, Y.; Shappee, B.; Beatty, T. G.; Salvo, C. Araya; Bird, J. C. [Department of Astronomy, The Ohio State University, 140 W 18th Ave, Columbus, OH 43210 (United States); Horne, Keith [SUPA Physics and Astronomy, University of St. Andrews, Fife, KY16 9SS Scotland (United Kingdom); Bentz, M. C. [Department of Physics and Astronomy, Georgia State University, Astronomy Offices, One Park Place South SE, Suite 700, Atlanta, GA 30303 (United States); Denney, K. D. [Marie Curie Fellow at the Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Siverd, R. [Department of Physics and Astronomy, Vanderbilt University, 5301 Stevenson Center, Nashville, TN 37235 (United States); Sergeev, S. G.; Borman, G. A. [Crimean Astrophysical Observatory, P/O Nauchny Crimea 98409 (Ukraine); Kaspi, S. [School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel); Bord, D. J. [Department of Natural Sciences, The University of Michigan - Dearborn, 4901 Evergreen Rd, Dearborn, MI 48128 (United States); Che, X. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 41809 (United States); and others

2013-02-10

We present velocity-resolved reverberation results for five active galactic nuclei. We recovered velocity-delay maps using the maximum entropy method for four objects: Mrk 335, Mrk 1501, 3C 120, and PG 2130+099. For the fifth, Mrk 6, we were only able to measure mean time delays in different velocity bins of the H{beta} emission line. The four velocity-delay maps show unique dynamical signatures for each object. For 3C 120, the Balmer lines show kinematic signatures consistent with both an inclined disk and infalling gas, but the He II {lambda}4686 emission line is suggestive only of inflow. The Balmer lines in Mrk 335, Mrk 1501, and PG 2130+099 show signs of infalling gas, but the He II emission in Mrk 335 is consistent with an inclined disk. We also see tentative evidence of combined virial motion and infalling gas from the velocity-binned analysis of Mrk 6. The maps for 3C 120 and Mrk 335 are two of the most clearly defined velocity-delay maps to date. These maps constitute a large increase in the number of objects for which we have resolved velocity-delay maps and provide evidence supporting the reliability of reverberation-based black hole mass measurements.

Reddening and He i{sup ∗} λ 10830 Absorption Lines in Three Narrow-line Seyfert 1 Galaxies

Energy Technology Data Exchange (ETDEWEB)

Zhang, Shaohua; Zhou, Hongyan; Shi, Xiheng; Pan, Xiang; Ji, Tuo; Jiang, Peng; Wang, Shufen [Polar Research Institute of China, 451 Jinqiao Road, Shanghai, 200136 (China); Liu, Wenjuan [Key Laboratory for the Structure and Evolution of Celestial Objects, Yunnan Observatories, Chinese Academy of Sciences, Kunming, Yunnan 650011 (China); Jiang, Ning, E-mail: zhangshaohua@pric.org.cn, E-mail: zhouhongyan@pric.org.cn [Key Laboratory for Researches in Galaxies and Cosmology, Department of Astronomy, University of Sciences and Technology of China, Chinese Academy of Sciences, Hefei, Anhui, 230026 (China)

2017-08-20

We report the detection of heavy reddening and the He i* λ 10830 absorption lines at the active galactic nucleus (AGN) redshift in three narrow-line Seyfert 1 galaxies: SDSS J091848.61+211717.0, SDSS J111354.66+124439.0, and SDSS J122749.13+321458.9. They exhibit very red optical to near-infrared colors, narrow Balmer/Paschen broad emission lines and He i* λ 10830 absorption lines. The ultraviolet-optical-infrared nucleus continua are reddened by the SMC extinction law of E ( B − V ) ∼ 0.74, 1.17, and 1.24 mag for three objects, which are highly consistent with the values obtained from the broad-line Balmer decrements, but larger than those of narrow emission lines. The reddening analysis suggests that the extinction dust simultaneously obscures the accretion disk, the broad emission-line region, and the hot dust from the inner edge of the torus. It is possible that the dust obscuring the AGN structures is the dusty torus itself. Furthermore, the Cloudy analysis of the He i* λ 10830 absorption lines proposes the distance of the absorption materials to be the extend scale of the torus, which greatly increases probabilities of the obscure and absorption materials being the dusty torus.

EDDINGTON RATIO DISTRIBUTION OF X-RAY-SELECTED BROAD-LINE AGNs AT 1.0 < z < 2.2

International Nuclear Information System (INIS)

Suh, Hyewon; Hasinger, Günther; Steinhardt, Charles; Silverman, John D.; Schramm, Malte

2015-01-01

We investigate the Eddington ratio distribution of X-ray-selected broad-line active galactic nuclei (AGNs) in the redshift range 1.0 < z < 2.2, where the number density of AGNs peaks. Combining the optical and Subaru/Fiber Multi Object Spectrograph near-infrared spectroscopy, we estimate black hole masses for broad-line AGNs in the Chandra Deep Field South (CDF-S), Extended Chandra Deep Field South (E-CDF-S), and the XMM-Newton Lockman Hole (XMM-LH) surveys. AGNs with similar black hole masses show a broad range of AGN bolometric luminosities, which are calculated from X-ray luminosities, indicating that the accretion rate of black holes is widely distributed. We find a substantial fraction of massive black holes accreting significantly below the Eddington limit at z ≲ 2, in contrast to what is generally found for luminous AGNs at high redshift. Our analysis of observational selection biases indicates that the “AGN cosmic downsizing” phenomenon can be simply explained by the strong evolution of the comoving number density at the bright end of the AGN luminosity function, together with the corresponding selection effects. However, one might need to consider a correlation between the AGN luminosity and the accretion rate of black holes, in which luminous AGNs have higher Eddington ratios than low-luminosity AGNs, in order to understand the relatively small fraction of low-luminosity AGNs with high accretion rates in this epoch. Therefore, the observed downsizing trend could be interpreted as massive black holes with low accretion rates, which are relatively fainter than less-massive black holes with efficient accretion

Neutrino-heated stars and broad-line emission from active galactic nuclei

Science.gov (United States)

Macdonald, James; Stanev, Todor; Biermann, Peter L.

1991-01-01

Nonthermal radiation from active galactic nuclei indicates the presence of highly relativistic particles. The interaction of these high-energy particles with matter and photons gives rise to a flux of high-energy neutrinos. In this paper, the influence of the expected high neutrino fluxes on the structure and evolution of single, main-sequence stars is investigated. Sequences of models of neutrino-heated stars in thermal equilibrium are presented for masses 0.25, 0.5, 0.8, and 1.0 solar mass. In addition, a set of evolutionary sequences for mass 0.5 solar mass have been computed for different assumed values for the incident neutrino energy flux. It is found that winds driven by the heating due to high-energy particles and hard electromagnetic radiation of the outer layers of neutrino-bloated stars may satisfy the requirements of the model of Kazanas (1989) for the broad-line emission clouds in active galactic nuclei.

Water line positions in the 782–840 nm region

International Nuclear Information System (INIS)

Hu, S.-M.; Chen, B.; Tan, Y.; Wang, J.; Cheng, C.-F.; Liu, A.-W.

2015-01-01

A set of water transitions in the 782–840 nm region, including 38 H 2 16 O lines, 12 HD 16 O lines, and 30 D 2 16 O lines, were recorded with a cavity ring-down spectrometer calibrated using precise atomic lines. Absolute frequencies of the lines were determined with an accuracy of about 5 MHz. Systematic shifts were found in the line positions given in the HITRAN database and the upper energy levels given in recent MARVEL studies. - Highlights: • Cavity ring-down spectra of H 2 16 O, HD 16 O, and D 2 16 O lines in the 782–840 nm region were measured. • Absolute line positions of 80 water lines were determined with an accuracy of about 5 MHz. • The H 2 16 O positions given in HITRAN have a systematic shift of 0.001 cm −1 in the 796–840 nm region. • MARVEL D 2 16 O energies have a systematic deviation of about −0.008 cm −1

A Test of the Formation Mechanism of the Broad Line Region in Active Galactic Nuclei

Czech Academy of Sciences Publication Activity Database

Czerny, B.; Du, P.; Wang, J.-M.; Karas, Vladimír

2016-01-01

Roč. 832, č. 1 (2016), 15/1-15/11 ISSN 0004-637X Institutional support: RVO:67985815 Keywords : galaxies * emission lines * active galaxies Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.533, year: 2016

Collision-induced stimulated photon echo generated at transition 0-1 on broad spectral line conditions

Science.gov (United States)

Rubtsova, N. N.; Gol'dort, V. G.; Ishchenko, V. N.; Khvorostov, E. B.; Kochubei, S. A.; Borisov, G. M.; Ledovskikh, D. V.; Reshetov, V. A.

2018-04-01

For the first time, the collision induced stimulated photon echo generated at transition 1S0 → 3 P1 of 174Yb (type 0-1) in the mixture of gases Yb  +  Xe was investigated in the presence of weak longitudinal magnetic field, with experimental parameters corresponding to broad spectral line conditions. Comparison of the experimental echo amplitude versus magnetic field strength dependence with the theoretical curve shows a very good agreement, giving rise to an improved estimate for the difference between alignment and orientation decay rates.

C IV BROAD ABSORPTION LINE ACCELERATION IN SLOAN DIGITAL SKY SURVEY QUASARS

Energy Technology Data Exchange (ETDEWEB)

Grier, C. J.; Brandt, W. N.; Trump, J. R.; Schneider, D. P.; Sun, M.; Beatty, T. G. [Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, Toronto, ON M3J 1P3 (Canada); Filiz Ak, N. [Faculty of Sciences, Department of Astronomy and Space Sciences, Erciyes University, 38039 Kayseri (Turkey); Anderson, S. F. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Green, Paul J. [Harvard Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138 (United States); Vivek, M.; Brownstein, Joel R. [Department of Physics and Astronomy, University of Utah, 115 S. 1400 E., Salt Lake City, UT 84112 (United States); Roman-Lopes, Alexandre, E-mail: grier@psu.edu [Departamento de Fisica, Facultad de Ciencias, Universidad de La Serena, Cisternas 1200, La Serena (Chile)

2016-06-20

We present results from the largest systematic investigation of broad absorption line (BAL) acceleration to date. We use spectra of 140 quasars from three Sloan Digital Sky Survey programs to search for global velocity offsets in BALs over timescales of ≈2.5–5.5 years in the quasar rest frame. We carefully select acceleration candidates by requiring monolithic velocity shifts over the entire BAL trough, avoiding BALs with velocity shifts that might be caused by profile variability. The C iv BALs of two quasars show velocity shifts consistent with the expected signatures of BAL acceleration, and the BAL of one quasar shows a velocity-shift signature of deceleration. In our two acceleration candidates, we see evidence that the magnitude of the acceleration is not constant over time; the magnitudes of the change in acceleration for both acceleration candidates are difficult to produce with a standard disk-wind model or via geometric projection effects. We measure upper limits to acceleration and deceleration for 76 additional BAL troughs and find that the majority of BALs are stable to within about 3% of their mean velocities. The lack of widespread acceleration/deceleration could indicate that the gas producing most BALs is located at large radii from the central black hole and/or is not currently strongly interacting with ambient material within the host galaxy along our line of sight.

On the Intermediate Line Region in AGNs

Energy Technology Data Exchange (ETDEWEB)

Adhikari, Tek P.; Różańska, Agata; Hryniewicz, Krzysztof [Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, Warsaw (Poland); Czerny, Bozena [Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, Warsaw (Poland); Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland); Ferland, Gary J., E-mail: tek@camk.edu.pl [Department of Physics and Astronomy, The University of Kentucky, Lexington, KY (United States)

2017-09-29

In this paper we explore the intermediate line region (ILR) by using the photoionisation simulations of the gas clouds present at different radial distances from the center, corresponding to the locations from BLR out to NLR in four types of AGNs. We let for the presence of dust whenever conditions allow for dust existence. All spectral shapes are taken from the recent multi-wavelength campaigns. The cloud density decreases with distance as a power law. We found that the slope of the power law density profile does not affect the line emissivity radial profiles of major emission lines: Hβ, He II, Mg II, C III, and O III. When the density of the cloud at the sublimation radius is as high as 10{sup 11.5} cm{sup −3}, the ILR should clearly be seen in the observations independently of the shape of the illuminating radiation. Moreover, our result is valid for low ionization nuclear emission regions of active galaxies.

Radio recombination lines from H II regions

International Nuclear Information System (INIS)

Silverglate, P.R.

1978-01-01

Radio recombination lines have been observed from forty-six H II regions. The Arecibo 1000-foot radio telescope was used to provide high sensitivity and high angular resolution at 1400 MHz (gain approx. 7.7 0 K/Jy, HPBW = 3:2) and 2372 MHZ (gain approx. 6.3 0 K/Jy, HPBW = 2'). Observations were made at 1400 MHz in the frequency switching mode, and at 2372 MHz in the total power mode. Gaussians were fit to be observed lines to derive velocities, line widths, and line temperatures. From the velocities kinematic distances were derived. For eleven sources H I absorption measurements were also made. The absorption spectra enabled the kinematic distance ambiguity to be resolved for some sources. The absorption spectra themselves were found to have extremely sharp, non-gaussian edges. One explanation for these is a model where the interstellar medium contains many H I cloudlets with T/sub s/less than or equal to 100 0 K and turbulent velocities less than or equal to 3 km/s. The H I absorption spectrum is then a superposition of many narrow gaussian profiles. It was also found from a comparison of H I absorption velocities with radio recombination line velocities that peculiar motions exist in the interstellar medium with velocities of up to 10 km/s. Using the measured line temperatures and continuum temperatures, estimates were desired of emission measures, electron temperatures, and electron densities, using a non-LTE analysis. Non-LTE effects were important only for the hottest and densest H II regions. The non-LTE calculations were checked through a comparison derivation of electron temperatures using hydrogen beta lines

Clustering Measurements of broad-line AGNs: Review and Future

Directory of Open Access Journals (Sweden)

Mirko Krumpe

2014-12-01

Full Text Available Despite substantial effort, the precise physical processes that lead to the growth of super-massive black holes in the centers of galaxies are still not well understood. These phases of black hole growth are thought to be of key importance in understanding galaxy evolution. Forthcoming missions such as eROSITA, HETDEX, eBOSS, BigBOSS, LSST, and Pan-STARRS will compile by far the largest ever Active Galactic Nuclei (AGNs catalogs which will allow us to measure the spatial distribution of AGNs in the universe with unprecedented accuracy. For the first time, AGN clustering measurements will reach a level of precision that will not only allow for an alternative approach to answering open questions in AGN and galaxy co-evolution but will open a new frontier, allowing us to precisely determine cosmological parameters. This paper reviews large-scale clustering measurements of broad line AGNs. We summarize how clustering is measured and which constraints can be derived from AGN clustering measurements, we discuss recent developments, and we briefly describe future projects that will deliver extremely large AGN samples which will enable AGN clustering measurements of unprecedented accuracy. In order to maximize the scientific return on the research fields of AGN and galaxy evolution and cosmology, we advise that the community develops a full understanding of the systematic uncertainties which will, in contrast to today’s measurement, be the dominant source of uncertainty.

INVESTIGATING THE COMPLEX X-RAY SPECTRUM OF A BROAD-LINE 2MASS RED QUASAR: XMM-NEWTON OBSERVATION OF FTM 0830+3759

International Nuclear Information System (INIS)

Piconcelli, Enrico; Nicastro, Fabrizio; Fiore, Fabrizio; Vignali, Cristian; Bianchi, Stefano; Miniutti, Giovanni

2010-01-01

We report results from a 50 ks XMM-Newton observation of the dust-reddened broad-line quasar FTM 0830+3759 (z = 0.413) selected from the Faint Images of the Radio Sky at Twenty cm/Two Micron All Sky Survey red quasar survey. For this active galactic nucleus (AGN), a very short 9 ks Chandra exposure had suggested a feature-rich X-ray spectrum and Hubble Space Telescope images revealed a very disturbed host galaxy morphology. Contrary to classical, optically selected quasars, the X-ray properties of red (i.e., with J - K s > 1.7 and R - K s > 4.0) broad-line quasars are still quite unexplored, although there is a growing consensus that, due to moderate obscuration, these objects can offer a unique view of spectral components typically swamped by the AGN light in normal, blue quasars. The XMM-Newton observation discussed here has definitely confirmed the complexity of the X-ray spectrum revealing the presence of a cold (or mildly ionized) absorber with N H ∼ 10 22 cm -2 along the line of sight to the nucleus and a Compton reflection component accompanied by an intense Fe Kα emission line in this quasar with a L 2-10 k eV ∼ 5 x 10 44 erg s -1 . A soft-excess component is also required by the data. The match between the column density derived by our spectral analysis and that expected on the basis of reddening due to the dust suggests the possibility that both absorptions occur in the same medium. FTM 0830+3759 is characterized by an extinction/absorption-corrected X-ray-to-optical flux ratio α ox = -2.3, which is steeper than expected on the basis of its UV luminosity. These findings indicate that the X-ray properties of FTM 0830+3759 differ from those typically observed for optically selected broad-line quasars with comparable hard X-ray luminosity.

Line-shape asymmetry of water vapor absorption lines in the 720-nm wavelength region

Science.gov (United States)

Grossmann, Benoist E.; Browell, Edward V.

1991-01-01

Spectral line-shape analyses were performed for water vapor lines broadened by argon, oxygen, and xenon in the 720-nm wavelength region. A line-shape asymmetry was observed, which is attributed to statistical dependence or correlation between velocity- and state-changing collisions. The generalized (asymmetric) Galatry profile, which results from the soft-collision profile and includes correlation between velocity- and state-changing collisions, was fitted to the observed line shapes and was found to compare favorably with the observed data. The most prominent asymmetries were observed with xenon as the buffer gas.

A Broad 22 Micron Emission Feature in the Carina Nebula H ii Region.

Science.gov (United States)

Chan; Onaka

2000-04-10

We report the detection of a broad 22 µm emission feature in the Carina Nebula H ii region by the Infrared Space Observatory (ISO) short-wavelength spectrometer. The feature shape is similar to that of the 22 µm emission feature of newly synthesized dust observed in the Cassiopeia A supernova remnant. This finding suggests that both of the features are arising from the same carrier and that supernovae are probably the dominant production sources of this new interstellar grain. A similar broad emission dust feature is also found in the spectra of two starburst galaxies from the ISO archival data. This new dust grain could be an abundant component of interstellar grains and can be used to trace the supernova rate or star formation rate in external galaxies. The existence of the broad 22 µm emission feature complicates the dust model for starburst galaxies and must be taken into account correctly in the derivation of dust color temperature. Mg protosilicate has been suggested as the carrier of the 22 µm emission dust feature observed in Cassiopeia A. The present results provide useful information in studies on the chemical composition and emission mechanism of the carrier.

Thomson Thick X-Ray Absorption in a Broad Absorption Line Quasar, PG 0946+301.

Science.gov (United States)

Mathur; Green; Arav; Brotherton; Crenshaw; deKool; Elvis; Goodrich; Hamann; Hines; Kashyap; Korista; Peterson; Shields; Shlosman; van Breugel W; Voit

2000-04-20

We present a deep ASCA observation of a broad absorption line quasar (BALQSO) PG 0946+301. The source was clearly detected in one of the gas imaging spectrometers, but not in any other detector. If BALQSOs have intrinsic X-ray spectra similar to normal radio-quiet quasars, our observations imply that there is Thomson thick X-ray absorption (NH greater, similar1024 cm-2) toward PG 0946+301. This is the largest column density estimated so far toward a BALQSO. The absorber must be at least partially ionized and may be responsible for attenuation in the optical and UV. If the Thomson optical depth toward BALQSOs is close to 1, as inferred here, then spectroscopy in hard X-rays with large telescopes like XMM would be feasible.

BROAD-LINE REVERBERATION IN THE KEPLER-FIELD SEYFERT GALAXY Zw 229-015

International Nuclear Information System (INIS)

Barth, Aaron J.; Nguyen, My L.; Malkan, Matthew A.; Filippenko, Alexei V.; Li, Weidong; Cenko, S. Bradley; Choi, Jieun; Duchene, Gaspard; Ganeshalingam, Mohan; Gorjian, Varoujan; Joner, Michael D.; Bennert, Vardha Nicola; Botyanszki, Janos; Childress, Michael; Cucciara, Antonino; Comerford, Julia M.; Da Silva, Robert; Fumagalli, Michele; Gates, Elinor L.; Gerke, Brian F.

2011-01-01

The Seyfert 1 galaxy Zw 229-015 is among the brightest active galaxies being monitored by the Kepler mission. In order to determine the black hole mass in Zw 229-015 from Hβ reverberation mapping, we have carried out nightly observations with the Kast Spectrograph at the Lick 3 m telescope during the dark runs from 2010 June through December, obtaining 54 spectroscopic observations in total. We have also obtained nightly V-band imaging with the Katzman Automatic Imaging Telescope at Lick Observatory and with the 0.9 m telescope at the Brigham Young University West Mountain Observatory over the same period. We detect strong variability in the source, which exhibited more than a factor of two change in broad Hβ flux. From cross-correlation measurements, we find that the Hβ light curve has a rest-frame lag of 3.86 +0.69 -0.90 days with respect to the V-band continuum variations. We also measure reverberation lags for Hα and Hγ and find an upper limit to the Hδ lag. Combining the Hβ lag measurement with a broad Hβ width of σ line = 1590 ± 47 km s -1 measured from the rms variability spectrum, we obtain a virial estimate of M BH = 1.00 +0.19 -0.24 x 10 7 M sun for the black hole in Zw 229-015. As a Kepler target, Zw 229-015 will eventually have one of the highest-quality optical light curves ever measured for any active galaxy, and the black hole mass determined from reverberation mapping will serve as a benchmark for testing relationships between black hole mass and continuum variability characteristics in active galactic nuclei.

Extended Narrow-Line Region in Seyfert Galaxies

Energy Technology Data Exchange (ETDEWEB)

Congiu, Enrico [Dipartimento di Fisica e Astronomia “G. Galilei”, Università di Padova, Padova (Italy); Astronomical Observatory of Brera, National Institute for Astrophysics, Milan (Italy); Contini, Marcella [School of Physics and Astronomy, Tel Aviv University, Tel Aviv (Israel); Ciroi, Stefano; Cracco, Valentina [Dipartimento di Fisica e Astronomia “G. Galilei”, Università di Padova, Padova (Italy); Di Mille, Francesco [Las Campanas Observatory, La Serena (Chile); Berton, Marco [Dipartimento di Fisica e Astronomia “G. Galilei”, Università di Padova, Padova (Italy); Astronomical Observatory of Brera, National Institute for Astrophysics, Milan (Italy); Frezzato, Michele; La Mura, Giovanni; Rafanelli, Piero, E-mail: enrico.congiu@phd.unipd.it [Dipartimento di Fisica e Astronomia “G. Galilei”, Università di Padova, Padova (Italy)

2017-10-24

We present our recent results about the extended narrow-line region (ENLR) of two nearby Seyfert 2 galaxies (IC 5063 and NGC 7212) obtained by modeling the observed line profiles and spectra with composite models (photoionization+shocks) in the different regions surrounding the AGN. Then, we compare the Seyfert 2 ENLRs with the very extended one recently discovered in the narrow-line Seyfert 1 (NLS1) galaxy Mrk 783. We have found several evidences of interaction between the ISM of the galaxies and their radio jets, such as (a) the contribution of shocks in ionizing the high velocity gas, (b) the complex kinematics showed by the profile of the emission lines, (c) the high fragmentation of matter, etc. The results suggest that the ENLR of IC 5063 have a hollow bi-conical shape, with one edge aligned to the galaxy disk, which may cause some kind of dependence on velocity of the ionization parameter. Regarding the Mrk 783 properties, it is found that the extension of the optical emission is almost twice the size of the radio one and it seems due to the AGN activity, although there is contamination by star formation around 12 arcsec from the nucleus. Diagnostic diagrams excluded the contribution of star formation in IC 5063 and NGC 7212, while the shock contribution was used to explain the spectra emitted by their high velocity gas.

Extended Narrow-Line Region in Seyfert Galaxies

International Nuclear Information System (INIS)

Congiu, Enrico; Contini, Marcella; Ciroi, Stefano; Cracco, Valentina; Di Mille, Francesco; Berton, Marco; Frezzato, Michele; La Mura, Giovanni; Rafanelli, Piero

2017-01-01

We present our recent results about the extended narrow-line region (ENLR) of two nearby Seyfert 2 galaxies (IC 5063 and NGC 7212) obtained by modeling the observed line profiles and spectra with composite models (photoionization+shocks) in the different regions surrounding the AGN. Then, we compare the Seyfert 2 ENLRs with the very extended one recently discovered in the narrow-line Seyfert 1 (NLS1) galaxy Mrk 783. We have found several evidences of interaction between the ISM of the galaxies and their radio jets, such as (a) the contribution of shocks in ionizing the high velocity gas, (b) the complex kinematics showed by the profile of the emission lines, (c) the high fragmentation of matter, etc. The results suggest that the ENLR of IC 5063 have a hollow bi-conical shape, with one edge aligned to the galaxy disk, which may cause some kind of dependence on velocity of the ionization parameter. Regarding the Mrk 783 properties, it is found that the extension of the optical emission is almost twice the size of the radio one and it seems due to the AGN activity, although there is contamination by star formation around 12 arcsec from the nucleus. Diagnostic diagrams excluded the contribution of star formation in IC 5063 and NGC 7212, while the shock contribution was used to explain the spectra emitted by their high velocity gas.

Broad band seismology in the Scotia region. The base Esperanza seismological observatory

International Nuclear Information System (INIS)

Russi, M.; Costa, G.; Febrer, J.

1995-08-01

The lithospheric study and the identification of relevant lateral heterogeneities in the Antarctic continent and borderlands, is essential to understand the geodynamic evolution both of the continental and oceanic bordering regions. The complexity of the geological evolution and the structural properties of the lithosphere in the Scotia area have been stressed by many authors. The present setting of the area is the result of the mutual interaction among the Antarctic, South American and several minor plants whose geodynamic history and actual boundaries are still partially unknown. The intense seismic activity that characterizes the region encourages the use of the seismological approach to investigate the lithospheric structure of the area. Since January 1992 a broad band three components station is operating at the Antarctic base Esperanza in the NE area of Antarctic Peninsula. The station has been installed with financial support of the Italian Programma Nazionale di Ricerche in Antartide (PNRA) by Osservatorio Geofisico Sperimentale (OGS) and Instituto Antartico Argentino (IAA). Russi et al. (1994) have analyzed selected recordings using the frequency-time analysis (FTAN) method obtaining some relevant information on the large scale structure of the lithosphere in the Scotia region even if data recorded by a single station were available. The extension of our analysis to further events and to horizontal component records is here presented. Within the framework of the international co-operation to the Antarctic Seismographic Network, the OGS and the IAA are upgrading the Esperanza station and installing an additional broad band station near the town of Ushuaia (Tierra del Fuego, Argentina) with the financial support of PNRA. The inversion of the dispersion curves through the FTAN of the signals recorded by an increased number of stations and generated by events with source-station paths spanning the region will allow us to extract the elastic and anelastic

Non-Maxwellian Analysis of the Transition-region Line Profiles Observed by the Interface Region Imaging Spectrograph

Energy Technology Data Exchange (ETDEWEB)

Dudík, Jaroslav; Dzifčáková, Elena [Astronomical Institute of the Czech Academy of Sciences, Fričova 298, 251 65 Ondřejov (Czech Republic); Polito, Vanessa; Testa, Paola [Smithsonian Astrophysical Observatory, 60 Garden Street, MS 58, Cambridge, MA 02138 (United States); Zanna, Giulio Del, E-mail: dudik@asu.cas.cz [Department of Applied Mathematics and Theoretical Physics, CMS, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

2017-06-10

We investigate the nature of the spectral line profiles for transition-region (TR) ions observed with the Interface Region Imaging Spectrograph (IRIS) . In this context, we analyzed an active-region observation performed by IRIS in its 1400 Å spectral window. The TR lines are found to exhibit significant wings in their spectral profiles, which can be well fitted with a non-Maxwellian κ distribution. The fit with a κ distribution can perform better than a double-Gaussian fit, especially for the strongest line, Si iv 1402.8 Å. Typical values of κ found are about 2, occurring in a majority of spatial pixels where the TR lines are symmetric, i.e., the fit can be performed. Furthermore, all five spectral lines studied (from Si iv, O iv, and S iv) appear to have the same full-width at half-maximum irrespective of whether the line is an allowed or an intercombination transition. A similar value of κ is obtained for the electron distribution by the fitting of the line intensities relative to Si iv 1402.8 Å, if photospheric abundances are assumed. The κ distributions, however, do not remove the presence of non-thermal broadening. Instead, they actually increase the non-thermal width. This is because, for κ distributions, TR ions are formed at lower temperatures. The large observed non-thermal width lowers the opacity of the Si iv line sufficiently enough for this line to become optically thin.

Broad Halpha Wing Formation in the Planetary Nebula IC 4997.

Science.gov (United States)

Lee; Hyung

2000-02-10

The young and compact planetary nebula IC 4997 is known to exhibit very broad wings with a width exceeding 5000 km s-1 around Halpha. We propose that the broad wings are formed through Rayleigh-Raman scattering that involves atomic hydrogen, by which Lybeta photons with a velocity width of a few 102 km s-1 are converted to optical photons and fill the Halpha broad wing region. The conversion efficiency reaches 0.6 near the line center, where the scattering optical depth is much larger than 1, and rapidly decreases in the far wings. Assuming that close to the central star there exists an unresolved inner compact core of high density, nH approximately 109-1010 cm-3, we use the photoionization code "CLOUDY" to show that sufficient Lybeta photons for scattering are produced. Using a top-hat-incident profile for the Lybeta flux and a scattering region with a H i column density NHi=2x1020 cm-2 and a substantial covering factor, we perform a profile-fitting analysis in order to obtain a satisfactory fit to the observed flux. We briefly discuss the astrophysical implications of the Rayleigh-Raman processes in planetary nebulae and other emission objects.

Extended Narrow-Line Region in Seyfert Galaxies

Directory of Open Access Journals (Sweden)

Enrico Congiu

2017-10-01

Full Text Available We present our recent results about the extended narrow-line region (ENLR of two nearby Seyfert 2 galaxies (IC 5063 and NGC 7212 obtained by modeling the observed line profiles and spectra with composite models (photoionization+shocks in the different regions surrounding the AGN. Then, we compare the Seyfert 2 ENLRs with the very extended one recently discovered in the narrow-line Seyfert 1 (NLS1 galaxy Mrk 783. We have found several evidences of interaction between the ISM of the galaxies and their radio jets, such as (a the contribution of shocks in ionizing the high velocity gas, (b the complex kinematics showed by the profile of the emission lines, (c the high fragmentation of matter, etc. The results suggest that the ENLR of IC 5063 have a hollow bi-conical shape, with one edge aligned to the galaxy disk, which may cause some kind of dependence on velocity of the ionization parameter. Regarding the Mrk 783 properties, it is found that the extension of the optical emission is almost twice the size of the radio one and it seems due to the AGN activity, although there is contamination by star formation around 12 arcsec from the nucleus. Diagnostic diagrams excluded the contribution of star formation in IC 5063 and NGC 7212, while the shock contribution was used to explain the spectra emitted by their high velocity gas.

MISALIGNMENT OF THE JET AND THE NORMAL TO THE DUSTY TORUS IN THE BROAD ABSORPTION LINE QSO FIRST J155633.8+351758

International Nuclear Information System (INIS)

Reynolds, Cormac; Punsly, Brian; O'Dea, Christopher P.

2013-01-01

We performed Very Long Baseline Array observations of the broad absorption line quasar FIRST J155633.8+351758, ''the first radio loud BALQSO''. Our observations at 15.3 GHz partially resolved a secondary component at position angle (P.A.) ≈35°. We combine this determination of the radio jet projection on the sky plane, with the constraint that the jet is viewed within 14.°3 of the line of sight (as implied by the high variability brightness temperature) and with the P.A. of the optical/UV continuum polarization in order to study the quasar geometry. Within the context of the standard model, the data indicates a ''dusty torus'' (scattering surface) with a symmetry axis tilted relative to the accretion disk normal and a polar broad absorption line outflow aligned with the accretion disk normal. We compare this geometry to that indicated by the higher resolution radio data, brightness temperature, and optical/UV continuum polarization P.A. of a similar high optical polarization BALQSO, Mrk 231. A qualitatively similar geometry is found in these two polar BALQSOs; the continuum polarization is determined primarily by the tilt of the dusty torus

THE LICK AGN MONITORING PROJECT 2011: SPECTROSCOPIC CAMPAIGN AND EMISSION-LINE LIGHT CURVES

Energy Technology Data Exchange (ETDEWEB)

Barth, Aaron J. [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA, 92697-4575 (United States); Bennert, Vardha N. [Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407 (United States); Canalizo, Gabriela [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Filippenko, Alexei V.; Li, Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Gates, Elinor L. [Lick Observatory, P.O. Box 85, Mount Hamilton, CA 95140 (United States); Greene, Jenny E. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Malkan, Matthew A.; Treu, Tommaso [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States); Pancoast, Anna [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Sand, David J. [Texas Tech University, Physics Department, Box 41051, Lubbock, TX 79409-1051 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Boulevard, Pasadena, CA 91109 (United States); Woo, Jong-Hak [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Assef, Roberto J. [Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago (Chile); Bae, Hyun-Jin [Department of Astronomy and Center for Galaxy Evolution Research, Yonsei University, Seoul 120-749 (Korea, Republic of); Brewer, Brendon J. [Department of Statistics, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Cenko, S. Bradley [Astrophysics Science Division, NASA Goddard Space Flight Center, MC 661, Greenbelt, MD 20771 (United States); and others

2015-04-15

In the Spring of 2011 we carried out a 2.5 month reverberation mapping campaign using the 3 m Shane telescope at Lick Observatory, monitoring 15 low-redshift Seyfert 1 galaxies. This paper describes the observations, reductions and measurements, and data products from the spectroscopic campaign. The reduced spectra were fitted with a multicomponent model in order to isolate the contributions of various continuum and emission-line components. We present light curves of broad emission lines and the active galactic nucleus (AGN) continuum, and measurements of the broad Hβ line widths in mean and rms spectra. For the most highly variable AGNs we also measured broad Hβ line widths and velocity centroids from the nightly spectra. In four AGNs exhibiting the highest variability amplitudes, we detect anticorrelations between broad Hβ width and luminosity, demonstrating that the broad-line region “breathes” on short timescales of days to weeks in response to continuum variations. We also find that broad Hβ velocity centroids can undergo substantial changes in response to continuum variations; in NGC 4593, the broad Hβ velocity shifted by ∼250 km s{sup −1} over a 1 month period. This reverberation-induced velocity shift effect is likely to contribute a significant source of confusion noise to binary black hole searches that use multi-epoch quasar spectroscopy to detect binary orbital motion. We also present results from simulations that examine biases that can occur in measurement of broad-line widths from rms spectra due to the contributions of continuum variations and photon-counting noise.

Aperture synthesis observations of recombination lines from compact HII regions

International Nuclear Information System (INIS)

Gorkom, J.H. van.

1980-01-01

This thesis describes a continuation of early attempts to attain a high spectral dynamic range in general and to study recombination lines from compact HII regions in particular. These observations are made with the WSRT, until recently, the only instrument with sufficient angular resolution and sensitivity to provide at 6 cm detailed line maps of compact HII regions. An investigation into the spectral stability of the WSRT is described. Chromatic errors were found and their effects on maps are shown. These errors were found in the 80 channel filter spectrometer which was still in use at that time. The advent of the digital line backend (DLB) improved the dynamic range by an order of magnitude. An experiment is described which was partially aimed at testing the spectral stability of the DLB. It concerns a search for HI emission from the high velocity system of NGC 1275. Recombination line observations of the compact components in five giant HII regions are presented. The author discusses the radiative transfer problem in recombination lines and shows that non-LTE effects and pressure broadening can be of importance in compact HII regions. Observations obtained with the DLB are also presented. Because of the much better instrumental quality and improved insight into calibration procedures, mapping the H110α emission of DR21 and both the H110α and H166α emission of W3 was succeeded. (Auth.)

BROAD ABSORPTION LINE DISAPPEARANCE ON MULTI-YEAR TIMESCALES IN A LARGE QUASAR SAMPLE

Energy Technology Data Exchange (ETDEWEB)

Filiz Ak, N.; Brandt, W. N.; Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, Ontario M3J 1P3 (Canada); Anderson, S. F.; Gibson, R. R. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Lundgren, B. F. [Department of Physics, Yale University, New Haven, CT 06511 (United States); Myers, A. D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Petitjean, P. [Institut d' Astrophysique de Paris, Universite Paris 6, F-75014, Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 92420 (United States); Shen Yue [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, MA 02138 (United States); York, D. G. [Department of Astronomy and Astrophysics, and Enrico Fermi Institute, University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637 (United States); Bizyaev, D.; Brinkmann, J.; Malanushenko, E.; Oravetz, D. J.; Pan, K.; Simmons, A. E. [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059 (United States); Weaver, B. A., E-mail: nfilizak@astro.psu.edu [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States)

2012-10-01

We present 21 examples of C IV broad absorption line (BAL) trough disappearance in 19 quasars selected from systematic multi-epoch observations of 582 bright BAL quasars (1.9 < z < 4.5) by the Sloan Digital Sky Survey-I/II (SDSS-I/II) and SDSS-III. The observations span 1.1-3.9 yr rest-frame timescales, longer than have been sampled in many previous BAL variability studies. On these timescales, Almost-Equal-To 2.3% of C IV BAL troughs disappear and Almost-Equal-To 3.3% of BAL quasars show a disappearing trough. These observed frequencies suggest that many C IV BAL absorbers spend on average at most a century along our line of sight to their quasar. Ten of the 19 BAL quasars showing C IV BAL disappearance have apparently transformed from BAL to non-BAL quasars; these are the first reported examples of such transformations. The BAL troughs that disappear tend to be those with small-to-moderate equivalent widths, relatively shallow depths, and high outflow velocities. Other non-disappearing C IV BALs in those nine objects having multiple troughs tend to weaken when one of them disappears, indicating a connection between the disappearing and non-disappearing troughs, even for velocity separations as large as 10,000-15,000 km s{sup -1}. We discuss possible origins of this connection including disk-wind rotation and changes in shielding gas.

Spectroscopic observations of Nova Cygni 1975: The coronal line region revisited

International Nuclear Information System (INIS)

Ferland, G.J.; Lambert, D.L.; Woodman, J.H.

1986-01-01

A synopsis of the McDonald Observatory spectrophotometric observations of Nova Cyg 1975 (V1500 Cyg) is presented. We present these data in a form in which they can be readily accessed in the future, and also study the continous spectrum during the early nebular phase. We show that (1) the remnant probably maintained a luminosity at or above the Eddington limit for at least a year after outburst, (2) free-free emission from the coronal line region made a significant contribution to the optical continuum, and (3) the coronal line region was probably a significant source of ionizing radiation. The energetics of this nova appear to be dominated by the lift-off energy from the white dwarf and radiation from the coronal line region. Thus the light curve of Nova Cyg may tell more about the cooling of the coronal line region than about the decline of the central object. In appendices we discuss the argon abundance of Nova Cyg (less than 8 times solar) and describe how to obtain copies of the McDonald nova data

X-RAYS FROM A RADIO-LOUD COMPACT BROAD ABSORPTION LINE QUASAR 1045+352 AND THE NATURE OF OUTFLOWS IN RADIO-LOUD BROAD ABSORPTION LINE QUASARS

International Nuclear Information System (INIS)

Kunert-Bajraszewska, Magdalena; Katarzynski, Krzysztof; Siemiginowska, Aneta; Janiuk, Agnieszka

2009-01-01

We present new results on X-ray properties of radio-loud broad absorption line (BAL) quasars and focus on broadband spectral properties of a high-ionization BAL (HiBAL) compact steep spectrum (CSS) radio-loud quasar 1045+352. This HiBAL quasar has a very complex radio morphology indicating either strong interactions between a radio jet and the surrounding interstellar medium or a possible re-start of the jet activity. We detected 1045+352 quasar in a short 5 ksec Chandra ACIS-S observation. We applied theoretical models to explain spectral energy distribution of 1045+352 and argue that non-thermal, inverse-Compton (IC) emission from the innermost parts of the radio jet can account for a large fraction of the observed X-ray emission. In our analysis, we also consider a scenario in which the observed X-ray emission from radio-loud BAL quasars can be a sum of IC jet X-ray emission and optically thin corona X-ray emission. We compiled a sample of radio-loud BAL quasars that were observed in X-rays to date and report no correlation between their X-ray and radio luminosity. However, the radio-loud BAL quasars show a large range of X-ray luminosities and absorption columns. This is consistent with the results obtained earlier for radio-quiet BAL quasars and may indicate an orientation effect in BAL quasars or more complex dependence between X-ray emission, radio emission, and an orientation based on the radio morphology.

Spectral properties of the narrow-line region in Seyfert galaxies selected from the SDSS-DR7

Science.gov (United States)

Vaona, L.; Ciroi, S.; Di Mille, F.; Cracco, V.; La Mura, G.; Rafanelli, P.

2012-12-01

Although the properties of the narrow-line region (NLR) of active galactic nuclei (AGN) have been deeply studied by many authors in the past three decades, many questions are still open. The main goal of this work is to explore the NLR of Seyfert galaxies by collecting a large statistical spectroscopic sample of Seyfert 2 and Intermediate-type Seyfert galaxies having a high signal-to-noise ratio in order to take advantage of a high number of emission lines to be accurately measured. 2153 Seyfert 2 and 521 Intermediate-type Seyfert spectra were selected from Sloan Digital Sky Survey Data Release 7 (SDSS-DR7) with a diagnostic diagram based on the oxygen emission-line ratios. All the emission lines, broad components included, were measured by means of a self-developed code, after the subtraction of the stellar component. Physical parameters, such as internal reddening, ionization parameter, temperature, density, gas and stellar velocity dispersion were determined for each object. Furthermore, we estimated mass and radius of the NLR, kinetic energy of the ionized gas and black hole accretion rate. From the emission-line analysis and the estimated physical properties, it appears that the NLR is similar in Seyfert 2 and Intermediate-Seyfert galaxies. The only differences, lower extinction, gas kinematics in general not dominated by the host galaxy gravitational potential and higher percentage of [O III]λ5007 blue asymmetries in Intermediate-Seyfert, can be ascribed to an effect of inclination of our line of sight with respect to the torus axis.

Broad-Band Spectroscopy of Hercules X-1 with Suzaku

Science.gov (United States)

Asami, Fumi; Enoto, Teruaki; Iwakiri, Wataru; Yamada, Shin'ya; Tamagawa, Toru; Mihara, Tatehiro; Nagase, Fumiaki

2014-01-01

Hercules X-1 was observed with Suzaku in the main-on state from 2005 to 2010. The 0.4- 100 keV wide-band spectra obtained in four observations showed a broad hump around 4-9 keV in addition to narrow Fe lines at 6.4 and 6.7 keV. The hump was seen in all the four observations regardless of the selection of the continuum models. Thus it is considered a stable and intrinsic spectral feature in Her X-1. The broad hump lacked a sharp structure like an absorption edge. Thus it was represented by two different spectral models: an ionized partial covering or an additional broad line at 6.5 keV. The former required a persistently existing ionized absorber, whose origin was unclear. In the latter case, the Gaussian fitting of the 6.5-keV line needs a large width of sigma = 1.0-1.5 keV and a large equivalent width of 400-900 eV. If the broad line originates from Fe fluorescence of accreting matter, its large width may be explained by the Doppler broadening in the accretion flow. However, the large equivalent width may be inconsistent with a simple accretion geometry.

[NEII] Line Velocity Structure of Ultracompact HII Regions

Science.gov (United States)

Okamoto, Yoshiko K.; Kataza, Hirokazu; Yamashita, Takuya; Miyata, Takashi; Sako, Shigeyuki; Honda, Mitsuhiko; Onaka, Takashi; Fujiyoshi, Takuya

Newly formed massive stars are embedded in their natal molecular clouds and are observed as ultracompact HII regions. They emit strong ionic lines such as [NeII] 12.8 micron. Since Ne is ionized by UV photons of E>21.6eV which is higher than the ionization energy of hydrogen atoms the line probes the ionized gas near the ionizing stars. This enables to probe gas motion in the vicinity of recently-formed massive stars. High angular and spectral resolution observations of the [NeII] line will thus provide siginificant information on structures (e.g. disks and outflows) generated through massive star formation. We made [NeII] spectroscopy of ultracompact HII regions using the Cooled Mid-Infrared Camera and Spectrometer (COMICS) on the 8.2m Subaru Telescope in July 2002. Spatial and spectral resolutions were 0.5"" and 10000 respectively. Among the targets G45.12+0.13 shows the largest spatial variation in velocity. The brightest area of G45.12+0.13 has the largest line width in the object. The total velocity deviation amounts to 50km/s (peak to peak value) in the observed area. We report the velocity structure of [NeII] emission of G45.12+0.13 and discuss the gas motion near the ionizing star.

Can double-peaked lines indicate merging effects in AGNs?

Directory of Open Access Journals (Sweden)

Popović L.Č.

2000-01-01

Full Text Available The influence of merging effects in the central part of an Active Galactic Nucleus (AGN on the emission spectral line shapes are discussed. We present a model of close binary Broad Line Region. The numerical experiments show that the merging effects can explain double peaked lines. The merging effects may also be present in the center of AGNs, although they emit slightly asymmetric as well as symmetric and relatively stable (in profile shape spectral lines. Depending on the black hole masses and their orbit elements such model may explain some of the line profile shapes observed in AGNs. This work shows that if one is looking for the merging effects in the central region as well as in the wide field structure of AGNs, he should first pay attention to objects which have double peaked lines.

FERO (Finding Extreme Relativistic Objects): statistics of relativistic broad Fe Kalpha lines in AGN

Czech Academy of Sciences Publication Activity Database

Longinotti, A. L.; de La Calle, I.; Bianchi, S.; Guainazzi, M.; Dovčiak, Michal

2008-01-01

Roč. 32, - (2008), s. 62-64 ISSN 1405-2059. [The Nuclear Region, Host Galaxy and Environment of Active Galaxies: A symposium to celebrate the 60th birthday of Deborah Dultzin. Huatulco, Oaxaca, 18.04.2007-20.04.2007] Institutional research plan: CEZ:AV0Z10030501 Keywords : active galaxies * line profiles * X-rays Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

DISCOVERY OF ULTRA-FAST OUTFLOWS IN A SAMPLE OF BROAD-LINE RADIO GALAXIES OBSERVED WITH SUZAKU

International Nuclear Information System (INIS)

Tombesi, F.; Sambruna, R. M.; Mushotzky, R. F.; Reeves, J. N.; Gofford, J.; Braito, V.; Ballo, L.; Cappi, M.

2010-01-01

We present the results of a uniform and systematic search for blueshifted Fe K absorption lines in the X-ray spectra of five bright broad-line radio galaxies observed with Suzaku. We detect, for the first time in radio-loud active galactic nuclei (AGNs) at X-rays, several absorption lines at energies greater than 7 keV in three out of five sources, namely, 3C 111, 3C 120, and 3C 390.3. The lines are detected with high significance according to both the F-test and extensive Monte Carlo simulations. Their likely interpretation as blueshifted Fe XXV and Fe XXVI K-shell resonance lines implies an origin from highly ionized gas outflowing with mildly relativistic velocities, in the range v ≅ 0.04-0.15c. A fit with specific photoionization models gives ionization parameters in the range log ξ ≅ 4-5.6 erg s -1 cm and column densities of N H ≅ 10 22 -10 23 cm -2 . These characteristics are very similar to those of the ultra-fast outflows (UFOs) previously observed in radio-quiet AGNs. Their estimated location within ∼0.01-0.3 pc of the central super-massive black hole suggests a likely origin related with accretion disk winds/outflows. Depending on the absorber covering fraction, the mass outflow rate of these UFOs can be comparable to the accretion rate and their kinetic power can correspond to a significant fraction of the bolometric luminosity and is comparable to their typical jet power. Therefore, these UFOs can play a significant role in the expected feedback from the AGN to the surrounding environment and can give us further clues on the relation between the accretion disk and the formation of winds/jets in both radio-quiet and radio-loud AGNs.

An emission-line model for AM Herculis systems

International Nuclear Information System (INIS)

Ferrario, L.; Tuohy, I.R.; Wickramasinghe, D.T.; Australian National Univ., Canberra)

1989-01-01

The optical spectra of the AM Herculis binaries are characterized by extremely complex emission lines whose profiles can be resolved into at least three components which are formed in different regions of the accretion stream leading from the companion star toward the magnetic white dwarf. A theoretical model is presented for the radial velocity and velocity dispersion of the broad emission line component assuming that it originates mainly in the gas which is diverted out of the orbital plane and funneled onto the white dwarf surface along magnetic field lines. The model is used to locate the line-forming region in three AM Her variables: E1405-451, CW 1103+254, and EXO 033319-2554.2, using as constraints the radial velocity and velocity dispersion data. The analyses of these systems show that the material is threaded by the magnetic field in a very azimuthally extended coupling region located 0.5-0.75 of the way between the white dwarf and the inner Lagrange point. 36 refs

A Survey of X-Ray Variability in Seyfert 1 Galaxies with XMM-Newton to study the soft excess and the broad Fe lines

Science.gov (United States)

Ponti, Gabriele

The nature of the soft excess and the presence of the broad Fe lines is still nowadays highly debated because the different absorption/emission models are degenerate. Spectral variability studies have the potential to break this degeneracy. I will present the results of a spectral variability RMS survey of the 36 brightest type 1 Seyfert galaxies observed by XMM-Newton for more than 30 ks. More than 80 as already measured, on longer timescales, with RXTE (Markowitz et al. 2004). About half of the sample show lower variability in the soft energy band, indicating that the emission from the soft excess is more stable than the one of the continuum. While the other sources show a soft excess that is as variable as the continuum. About half of the sample do not show an excess of variability where the warm absorber component imprints its stronger features, suggesting that for these sources the soft excess is not produced by a relativistic absorbing wind. In a few bright and well exposed sources it has been possible to measure an excess of variability at the energy of the broad component of the Fe K line, in agreement with the broad emission line interpretation. For the sources where more than one observation was available the stability of the shape of the RMS spectrum has been investigated. Moreover, it will be presented the results of the computation of the excess variance of all the radio quiet type 1 AGN of the XMM-Newton database. The relations between variability, black hole mass, accretion rate and luminosity are investigated and their scatter measured.

Broad-band properties of the CfA Seyfert galaxies. III - Ultraviolet variability

Science.gov (United States)

Edelson, R. A.; Pike, G. F.; Krolik, J. H.

1990-01-01

A total of 657 archived IUE spectra are used to study the UV variability properties of six members of the CfA Seyfert I galaxy sample. All show strong evidence for continuum and line variations and a tendency for less luminous objects to be more strongly variable. Most objects show a clear correlation at zero lag between UV spectral index and luminosity, evidence that the variable component is an accretion disk around a black hole which is systematically smaller in less luminous sources. No correlation is seen between the continuum luminosity and equivalent width of the C IV, Mg II, and semiforbidden C III emission lines when the entire sample is examined, but a clear anticorrelation is present when only repeated observations of individual objects are considered. This is due to a combination of light-travel time effects in the broad-line region and the nonlinear responses of lines to continuum fluctuations.

BROAD ABSORPTION LINE VARIABILITY ON MULTI-YEAR TIMESCALES IN A LARGE QUASAR SAMPLE

Energy Technology Data Exchange (ETDEWEB)

Filiz Ak, N.; Brandt, W. N.; Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, Ontario, M3J 1P3 (Canada); Anderson, S. F. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Hamann, F. [Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States); Lundgren, B. F. [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Pâris, I. [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Petitjean, P. [Universite Paris 6, Institut d' Astrophysique de Paris, 75014, Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 92420 (United States); Shen, Yue [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-51, Cambridge, MA 02138 (United States); York, Don, E-mail: nfilizak@astro.psu.edu [The University of Chicago, Department of Astronomy and Astrophysics, Chicago, IL 60637 (United States)

2013-11-10

We present a detailed investigation of the variability of 428 C IV and 235 Si IV broad absorption line (BAL) troughs identified in multi-epoch observations of 291 quasars by the Sloan Digital Sky Survey-I/II/III. These observations primarily sample rest-frame timescales of 1-3.7 yr over which significant rearrangement of the BAL wind is expected. We derive a number of observational results on, e.g., the frequency of BAL variability, the velocity range over which BAL variability occurs, the primary observed form of BAL-trough variability, the dependence of BAL variability upon timescale, the frequency of BAL strengthening versus weakening, correlations between BAL variability and BAL-trough profiles, relations between C IV and Si IV BAL variability, coordinated multi-trough variability, and BAL variations as a function of quasar properties. We assess implications of these observational results for quasar winds. Our results support models where most BAL absorption is formed within an order-of-magnitude of the wind-launching radius, although a significant minority of BAL troughs may arise on larger scales. We estimate an average lifetime for a BAL trough along our line-of-sight of a few thousand years. BAL disappearance and emergence events appear to be extremes of general BAL variability, rather than being qualitatively distinct phenomena. We derive the parameters of a random-walk model for BAL EW variability, finding that this model can acceptably describe some key aspects of EW variability. The coordinated trough variability of BAL quasars with multiple troughs suggests that changes in 'shielding gas' may play a significant role in driving general BAL variability.

SN 2010ay IS A LUMINOUS AND BROAD-LINED TYPE Ic SUPERNOVA WITHIN A LOW-METALLICITY HOST GALAXY

Energy Technology Data Exchange (ETDEWEB)

Sanders, N. E.; Soderberg, A. M.; Foley, R. J.; Chornock, R.; Chomiuk, L.; Berger, E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Valenti, S.; Smartt, S.; Botticella, M. T. [Astrophysics Research Centre, School of Maths and Physics, Queen' s University, Belfast BT7 1NN (United Kingdom); Hurley, K. [Space Sciences Laboratory, University of California Berkeley, 7 Gauss Way, Berkeley, CA 94720 (United States); Barthelmy, S. D.; Gehrels, N.; Cline, T. [NASA Goddard Space Flight Center, Code 661, Greenbelt, MD 20771 (United States); Levesque, E. M. [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Narayan, G. [Department of Physics, Harvard University, Cambridge, MA 02138 (United States); Briggs, M. S.; Connaughton, V. [CSPAR, University of Alabama in Huntsville, Huntsville, AL (United States); Terada, Y. [Department of Physics, Saitama University, Shimo-Okubo, Sakura-ku, Saitama-shi, Saitama 338-8570 (Japan); Golenetskii, S.; Mazets, E., E-mail: nsanders@cfa.harvard.edu [Ioffe Physico-Technical Institute, Laboratory for Experimental Astrophysics, 26 Polytekhnicheskaya, St. Petersburg 194021 (Russian Federation); and others

2012-09-10

We report on our serendipitous pre-discovery detection and follow-up observations of the broad-lined Type Ic supernova (SN Ic) 2010ay at z = 0.067 imaged by the Pan-STARRS1 3{pi} survey just {approx}4 days after explosion. The supernova (SN) had a peak luminosity, M{sub R} Almost-Equal-To -20.2 mag, significantly more luminous than known GRB-SNe and one of the most luminous SNe Ib/c ever discovered. The absorption velocity of SN 2010ay is v{sub Si} Almost-Equal-To 19 Multiplication-Sign 10{sup 3} km s{sup -1} at {approx}40 days after explosion, 2-5 times higher than other broad-lined SNe and similar to the GRB-SN 2010bh at comparable epochs. Moreover, the velocity declines {approx}2 times slower than other SNe Ic-BL and GRB-SNe. Assuming that the optical emission is powered by radioactive decay, the peak magnitude implies the synthesis of an unusually large mass of {sup 56}Ni, M{sub Ni} = 0.9 M{sub Sun }. Applying scaling relations to the light curve, we estimate a total ejecta mass, M{sub ej} Almost-Equal-To 4.7 M{sub Sun }, and total kinetic energy, E{sub K} Almost-Equal-To 11 Multiplication-Sign 10{sup 51} erg. The ratio of M{sub Ni} to M{sub ej} is {approx}2 times as large for SN 2010ay as typical GRB-SNe and may suggest an additional energy reservoir. The metallicity (log (O/H){sub PP04} + 12 = 8.19) of the explosion site within the host galaxy places SN 2010ay in the low-metallicity regime populated by GRB-SNe, and {approx}0.5(0.2) dex lower than that typically measured for the host environments of normal (broad-lined) SNe Ic. We constrain any gamma-ray emission with E{sub {gamma}} {approx}< 6 Multiplication-Sign 10{sup 48} erg (25-150 keV), and our deep radio follow-up observations with the Expanded Very Large Array rule out relativistic ejecta with energy E {approx}> 10{sup 48} erg. We therefore rule out the association of a relativistic outflow like those that accompanied SN 1998bw and traditional long-duration gamma-ray bursts (GRBs), but we place less

Parsec-Scale Radio Structure and Broad Optical Emission Lines in a Complete Sample of 3CR Lobe-dominated Quasars

Science.gov (United States)

Hough, D. H.; Vermeulen, R. C.; Readhead, A. C. S.; Cross, L. L.; Barth, E. L.; Yu, L. H.; Beyer, P. J.; Phifer, E. M.

2002-03-01

-dominated quasars. We have also defined a new postulated measure of orientation, based on both prominence of the radio nucleus and projected linear size, that correlates very well with properties predicted to have strong orientation dependence on beaming models. Finally, we confirm earlier studies demonstrating an anticorrelation between the prominence of the radio nucleus and the width of broad Mg II λ2798 optical emission lines; we also extend this result to C III] λ1909 and, more generally, to all broad lines by simple scaling and normalization methods. This relationship suggests a restricted range of orientations for LDQs, and that the broad-line clouds may have a flattened distribution associated with the accretion zone surrounding a central supermassive black hole.

WHY IS NON-THERMAL LINE BROADENING OF SPECTRAL LINES IN THE LOWER TRANSITION REGION OF THE SUN INDEPENDENT OF SPATIAL RESOLUTION?

International Nuclear Information System (INIS)

De Pontieu, B.; Martinez-Sykora, J.; McIntosh, S.; Peter, H.; Pereira, T. M. D.

2015-01-01

Spectral observations of the solar transition region (TR) and corona show broadening of spectral lines beyond what is expected from thermal and instrumental broadening. The remaining non-thermal broadening is significant (5–30 km s −1 ) and correlated with intensity. Here we study spectra of the TR Si iv 1403 Å line obtained at high resolution with the Interface Region Imaging Spectrograph (IRIS). We find that the large improvement in spatial resolution (0.″33) of IRIS compared to previous spectrographs (2″) does not resolve the non-thermal line broadening which, in most regions, remains at pre-IRIS levels of about 20 km s −1 . This invariance to spatial resolution indicates that the processes behind the broadening occur along the line-of-sight (LOS) and/or on spatial scales (perpendicular to the LOS) smaller than 250 km. Both effects appear to play a role. Comparison with IRIS chromospheric observations shows that, in regions where the LOS is more parallel to the field, magneto-acoustic shocks driven from below impact the TR and can lead to significant non-thermal line broadening. This scenario is supported by MHD simulations. While these do not show enough non-thermal line broadening, they do reproduce the long-known puzzling correlation between non-thermal line broadening and intensity. This correlation is caused by the shocks, but only if non-equilibrium ionization is taken into account. In regions where the LOS is more perpendicular to the field, the prevalence of small-scale twist is likely to play a significant role in explaining the invariance and correlation with intensity. (letters)

Molecular and Recombination Lines in the Central Region of Sagittarius B2

Science.gov (United States)

Curtis, J.; Langston, G.

2005-12-01

We present observations of recombination and molecular lines towards Sgr B2 in the frequency range 12.4 to 15.0 GHz. In this frequency range, Hα , β , and γ lines, Heα recombination lines and emission from the SO molecule are detected. Molecular absorption lines from OH, H2CO, and CH3CO are detected at velocity 62±3 km/s. Measurements of the line widths and intensities are presented for the central region of Sgr B2. We detect two previously un-reported molecular absorption lines at 12388.0 and 14625.8 MHz (v=0. in LSR Frame). For selected recombination and molecular lines, we present images of a 10x10 arc-minute region centered on Sgr B2(M). We discuss the sources of three H2CO absorption features detected at 62±3, 6±5, and 100±10 km/s. This was done as a summer REU project in 2005 at the National Radio Astronomy Observatory's Green Bank site, and was funded by the National Science Foundation's REU program.

Modeling the Broad-Band Emission from the Gamma-Ray Emitting Narrow-Line Seyfert-1 Galaxies 1H 0323+342 and B2 0954+25A

International Nuclear Information System (INIS)

Arrieta-Lobo, Maialen; Boisson, Catherine; Zech, Andreas

2017-01-01

Prior to the Fermi-LAT era, only two classes of Active Galactic Nuclei (AGN) were thought to harbor relativistic jets that radiate up to gamma-ray energies: blazars and radio galaxies. The detection of variable gamma-ray emission from Narrow Line Seyfert 1 (NLSy1) galaxies has put them on the spotlight as a new class of gamma-ray emitting AGN. In this respect, gamma-ray emitting NLSy1s seem to be situated between blazars (dominated by non-thermal emission) and Seyferts (accretion disc dominated). In this work, we model the Spectral Energy Distribution (SED) of two gamma-loud NLSy1s, 1H 0323+342 and B2 0954+25A, during quiescent and flaring episodes via a multi-component radiative model that features a relativistic jet and external photon fields from the torus, disc, corona and Broad Line Region (BLR). We find that the interpretation of the high-energy emission of jetted NLSy1s requires taking into account Inverse Compton emission from particles in the relativistic jet that interact with external photon fields. Minimal changes are applied to the model parameters to transition from average to flaring states. In this scenario, the observed variability is explained mainly by means of changes in the jet density and Doppler factor.

Modeling the Broad-Band Emission from the Gamma-Ray Emitting Narrow-Line Seyfert-1 Galaxies 1H 0323+342 and B2 0954+25A

Energy Technology Data Exchange (ETDEWEB)

Arrieta-Lobo, Maialen; Boisson, Catherine; Zech, Andreas, E-mail: maialen.arrieta@obspm.fr [Laboratoire Univers et Theories, Observatoire de Paris, CNRS, Université Paris-Diderot, PSL Research University, Meudon (France)

2017-12-08

Prior to the Fermi-LAT era, only two classes of Active Galactic Nuclei (AGN) were thought to harbor relativistic jets that radiate up to gamma-ray energies: blazars and radio galaxies. The detection of variable gamma-ray emission from Narrow Line Seyfert 1 (NLSy1) galaxies has put them on the spotlight as a new class of gamma-ray emitting AGN. In this respect, gamma-ray emitting NLSy1s seem to be situated between blazars (dominated by non-thermal emission) and Seyferts (accretion disc dominated). In this work, we model the Spectral Energy Distribution (SED) of two gamma-loud NLSy1s, 1H 0323+342 and B2 0954+25A, during quiescent and flaring episodes via a multi-component radiative model that features a relativistic jet and external photon fields from the torus, disc, corona and Broad Line Region (BLR). We find that the interpretation of the high-energy emission of jetted NLSy1s requires taking into account Inverse Compton emission from particles in the relativistic jet that interact with external photon fields. Minimal changes are applied to the model parameters to transition from average to flaring states. In this scenario, the observed variability is explained mainly by means of changes in the jet density and Doppler factor.

Extreme Emission Line Galaxies in CANDELS: Broad-Band Selected, Star-Bursting Dwarf Galaxies at Z greater than 1

Science.gov (United States)

vanderWel, A.; Straughn, A. N.; Rix, H.-W.; Finkelstein, S. L.; Koekemoer, A. M.; Weiner, B. J.; Wuyts, S.; Bell, E. F.; Faber, S. M.; Trump, J. R.;

DETECTION OF REST-FRAME OPTICAL LINES FROM X-SHOOTER SPECTROSCOPY OF WEAK EMISSION-LINE QUASARS

International Nuclear Information System (INIS)

Plotkin, Richard M.; Gallo, Elena; Shemmer, Ohad; Trakhtenbrot, Benny; Anderson, Scott F.; Brandt, W. N.; Luo, Bin; Schneider, Donald P.; Fan, Xiaohui; Lira, Paulina; Richards, Gordon T.; Strauss, Michael A.; Wu, Jianfeng

2015-01-01

Over the past 15 yr, examples of exotic radio-quiet quasars with intrinsically weak or absent broad emission line regions (BELRs) have emerged from large-scale spectroscopic sky surveys. Here, we present spectroscopy of seven such weak emission line quasars (WLQs) at moderate redshifts (z = 1.4–1.7) using the X-shooter spectrograph, which provides simultaneous optical and near-infrared spectroscopy covering the rest-frame ultraviolet (UV) through optical. These new observations effectively double the number of WLQs with spectroscopy in the optical rest-frame, and they allow us to compare the strengths of (weak) high-ionization emission lines (e.g., C iv) to low-ionization lines (e.g., Mg ii, Hβ, Hα) in individual objects. We detect broad Hβ and Hα emission in all objects, and these lines are generally toward the weaker end of the distribution expected for typical quasars (e.g., Hβ has rest-frame equivalent widths ranging from 15–40 Å). However, these low-ionization lines are not exceptionally weak, as is the case for high-ionization lines in WLQs. The X-shooter spectra also display relatively strong optical Fe ii emission, Hβ FWHM ≲ 4000 km s −1 , and significant C iv blueshifts (≈1000–5500 km s −1 ) relative to the systemic redshift; two spectra also show elevated UV Fe ii emission, and an outflowing component to their (weak) Mg ii emission lines. These properties suggest that WLQs are exotic versions of “wind-dominated” quasars. Their BELRs either have unusual high-ionization components, or their BELRs are in an atypical photoionization state because of an unusually soft continuum

Morphology of AGN Emission Line Regions in SDSS-IV MaNGA Survey

Science.gov (United States)

He, Zhicheng; Sun, Ai-Lei; Zakamska, Nadia L.; Wylezalek, Dominika; Kelly, Michael; Greene, Jenny E.; Rembold, Sandro B.; Riffel, Rogério; Riffel, Rogemar A.

2018-05-01

Extended narrow-line regions (NLRs) around active galactic nuclei (AGN) are shaped by the distribution of gas in the host galaxy and by the geometry of the circumnuclear obscuration, and thus they can be used to test the AGN unification model. In this work, we quantify the morphologies of the narrow-line regions in 308 nearby AGNs (z = 0 - 0.14, Lbol˜1042.4 - 44.1 erg s-1) from the MaNGA survey. Based on the narrow-line region maps, we find that a large fraction (81%) of these AGN have bi-conical NLR morphology. The distribution of their measured opening angles suggests that the intrinsic opening angles of the ionization cones has a mean value of 85-98° with a finite spread of 39-44° (1-σ). Our inferred opening angle distribution implies a number ratio of type I to type II AGN of 1:1.6-2.3, consistent with other measurements of the type I / type II ratio at low AGN luminosities. Combining these measurements with the WISE photometry data, we find that redder mid-IR color (lower effective temperature of dust) corresponds to stronger and narrower photo-ionized bicones. This relation is in agreement with the unification model that suggests that the bi-conical narrow-line regions are shaped by a toroidal dusty structure within a few pc from the AGN. Furthermore, we find a significant alignment between the minor axis of host galaxy disks and AGN ionization cones. Together, these findings suggest that obscuration on both circumnuclear (˜pc) and galactic (˜ kpc) scales are important in shaping and orienting the AGN narrow-line regions.

Peculiar A star HD 43819 - A photographic region line-identification study

International Nuclear Information System (INIS)

Adelman, S.J.; The Citadel, Charleston, SC)

1985-01-01

A line identification study of the sharp-lined silicon star HD 43819 has been performed for the photographic region 3759-4924 A. Comparison of this star's spectrum with those of other silicon stars shows that it shares many of their apparent abundance anomalies. The TiII, CrII, FeI, and FeII spectra are well represented while the singly ionized rare earths are represented by at best a few lines per species. 21 references

Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution

Czech Academy of Sciences Publication Activity Database

Czerny, B.; Li, Y.-R.; Hryniewicz, K.; Panda, S.; Wildy, C.; Sniegowska, M.; Wang, J.-M.; Sredzinska, J.; Karas, Vladimír

2017-01-01

Roč. 846, č. 2 (2017), 154/1-154/13 ISSN 0004-637X R&D Projects: GA MŠk LD15061 Institutional support: RVO:67985815 Keywords : accretion disks * active galaxies * line formation Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics OBOR OECD: Astronomy (including astrophysics,space science) Impact factor: 5.533, year: 2016

DISSECTING THE POWER SOURCES OF LOW-LUMINOSITY EMISSION-LINE GALAXY NUCLEI VIA COMPARISON OF HST-STIS AND GROUND-BASED SPECTRA

Energy Technology Data Exchange (ETDEWEB)

Constantin, Anca; Castillo, Christopher A. [Department of Physics and Astronomy, James Madison University, Harrisonburg, VA 22807 (United States); Shields, Joseph C. [Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Barth, Aaron J. [Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)

2015-12-01

Using a sample of ∼100 nearby line-emitting galaxy nuclei, we have built the currently definitive atlas of spectroscopic measurements of Hα and neighboring emission lines at subarcsecond scales. We employ these data in a quantitative comparison of the nebular emission in Hubble Space Telescope (HST) and ground-based apertures, which offer an order-of-magnitude difference in contrast, and provide new statistical constraints on the degree to which transition objects and low-ionization nuclear emission-line regions (LINERs) are powered by an accreting black hole at ≲10 pc. We show that while the small-aperture observations clearly resolve the nebular emission, the aperture dependence in the line ratios is generally weak, and this can be explained by gradients in the density of the line-emitting gas: the higher densities in the more nuclear regions potentially flatten the excitation gradients, suppressing the forbidden emission. The transition objects show a threefold increase in the incidence of broad Hα emission in the high-resolution data, as well as the strongest density gradients, supporting the composite model for these systems as accreting sources surrounded by star-forming activity. The narrow-line LINERs appear to be the weaker counterparts of the Type 1 LINERs, where the low accretion rates cause the disappearance of the broad-line component. The enhanced sensitivity of the HST observations reveals a 30% increase in the incidence of accretion-powered systems at z ≈ 0. A comparison of the strength of the broad-line emission detected at different epochs implies potential broad-line variability on a decade-long timescale, with at least a factor of three in amplitude.

A GRB and Broad-lined Type Ic Supernova from a Single Central Engine

Science.gov (United States)

Barnes, Jennifer; Duffell, Paul C.; Liu, Yuqian; Modjaz, Maryam; Bianco, Federica B.; Kasen, Daniel; MacFadyen, Andrew I.

2018-06-01

Unusually high velocities (≳0.1c) and correspondingly high kinetic energies have been observed in a subset of Type Ic supernovae (so-called “broad-lined Ic” supernovae; SNe Ic-BL), prompting a search for a central engine model capable of generating such energetic explosions. A clue to the explosion mechanism may lie in the fact that all supernovae that accompany long-duration gamma-ray bursts (GRBs) belong to the SN Ic-BL class. Using a combination of two-dimensional relativistic hydrodynamics and radiation transport calculations, we demonstrate that the central engine responsible for long GRBs can also trigger an SN Ic-BL. We find that a reasonable GRB engine injected into a stripped Wolf–Rayet progenitor produces a relativistic jet with energy ∼1051 erg, as well as an SN whose synthetic light curves and spectra are fully consistent with observed SNe Ic-BL during the photospheric phase. As a result of the jet’s asymmetric energy injection, the SN spectra and light curves depend on viewing angle. The impact of viewing angle on the spectrum is particularly pronounced at early times, while the viewing-angle dependence for the light curves (∼10% variation in bolometric luminosity) persists throughout the photospheric phase.

Regional seismic lines reprocessed using post-stack processing techniques; National Petroleum Reserve, Alaska

Science.gov (United States)

Miller, John J.; Agena, W.F.; Lee, M.W.; Zihlman, F.N.; Grow, J.A.; Taylor, D.J.; Killgore, Michele; Oliver, H.L.

2000-01-01

This CD-ROM contains stacked, migrated, 2-Dimensional seismic reflection data and associated support information for 22 regional seismic lines (3,470 line-miles) recorded in the National Petroleum Reserve ? Alaska (NPRA) from 1974 through 1981. Together, these lines constitute about one-quarter of the seismic data collected as part of the Federal Government?s program to evaluate the petroleum potential of the Reserve. The regional lines, which form a grid covering the entire NPRA, were created by combining various individual lines recorded in different years using different recording parameters. These data were reprocessed by the USGS using modern, post-stack processing techniques, to create a data set suitable for interpretation on interactive seismic interpretation computer workstations. Reprocessing was done in support of ongoing petroleum resource studies by the USGS Energy Program. The CD-ROM contains the following files: 1) 22 files containing the digital seismic data in standard, SEG-Y format; 2) 1 file containing navigation data for the 22 lines in standard SEG-P1 format; 3) 22 small scale graphic images of each seismic line in Adobe Acrobat? PDF format; 4) a graphic image of the location map, generated from the navigation file, with hyperlinks to the graphic images of the seismic lines; 5) an ASCII text file with cross-reference information for relating the sequential trace numbers on each regional line to the line number and shotpoint number of the original component lines; and 6) an explanation of the processing used to create the final seismic sections (this document). The SEG-Y format seismic files and SEG-P1 format navigation file contain all the information necessary for loading the data onto a seismic interpretation workstation.

Variation of nuclear radii in the drip line regions

CERN Document Server

Beiner, M; Mas, D

1976-01-01

The authors are concerned with predictions of the energy density method with respect to the nuclear sizes (RMS radii). It is known that the commonly accepted A/sup 1/3/-type laws are only approximative and deviations are expected to grow significantly as one goes away from the beta -stability region. Particular attention is paid to the variation of nuclear radii in the drip line regions. Implications of the resulting large total Coulomb energy variations between neighbouring nuclei will be emphasized.

Crossing a Broad Gray Line to Help Children

Science.gov (United States)

Allen, Megan M.

2015-01-01

Helping students with mental health issues sometimes presents teachers with the dilemma of following the letter of school rules or doing what is best for the child. One teacher tells her story of crossing such lines, but only in service to children. She also outlines what teachers can and should do to help students who need mental health services.

Detailed observations of NGC 4151 with IUE-III. Variability of the strong emission lines from 1978 February to 1980 May

International Nuclear Information System (INIS)

Ulrich, M.H.; Boksenberg, A.; Bromage, G.E.

1983-11-01

Observations of the variability of the three strong ultraviolet emission lines in the Seyfert galaxy NGC 4151 (CIV, CIII, and MgII) are used to study the structure of the broad line region and the nuclear energy source of this active galaxy. (author)

Investigating the reasons of variability in Si IV and C IV broad absorption line troughs of quasars

Science.gov (United States)

Stathopoulos, Dimitrios; Lyratzi, Evangelia; Danezis, Emmanuel; Antoniou, Antonios; Tzimeas, Dimitrios

2017-09-01

In this paper we analyze the C IV and Si IV broad absorption troughs of two BALQSOs (J101056.69+355833.3, J114548.38+393746.6) to the individual components they consist of. By analyzing a BAL trough to its components we have the advantage to study the variations of the individual absorbing systems in the line of sight and not just the variations of the whole absorption trough or the variations of selected portions of BAL troughs exhibiting changes. We find that the velocity shifts and FWHMs (Full Width at Half Maximum) of the individual components do not vary between an interval of six years. All variable components show changes in the optical depths at line centers which are manifested as variations in the EW (Equivalent Width) of the components. In both BALQSOs, over corresponding velocities, Si IV has higher incidence of variability than C IV. From our analysis, evidence is in favour of different covering fractions between C IV and Si IV. Finally, although most of our results favour the crossing cloud scenario as the cause of variability, there is also strong piece of evidence indicating changing ionization as the source of variability. Thus, a mixed situation where both physical mechanisms contribute to BAL variability is the most possible scenario.

Line formation in the solar chromosphere. II - An optically thick region of the chromosphere-corona transition region observed with OSO 8

Science.gov (United States)

Lites, B. W.; Hansen, E. R.; Shine, R. A.

1980-01-01

The University of Colorado ultraviolet spectrometer aboard the Orbiting Solar Observatory 8(OSO 8) has measured self-reversed profiles of the resonance line of C IV lamda 1548.2 at the limb passage of an active region. The degree of the self-reversal together with the absolute intensity of the line profile determine the electron density in the active region at 10 to the 10th/cu cm at temperatures where the C IV line is formed. The nonthermal component of the broadening velocity is no more than 14km/s, and the physical thickness of an equivalent plane-parallel slab in hydrostatic equilibrium that would give rise to the observed line profiles is about 430 km.

Weak Hard X-Ray Emission from Broad Absorption Line Quasars: Evidence for Intrinsic X-Ray Weakness

DEFF Research Database (Denmark)

Luo, B.; Brandt, W. N.; Alexander, D. M.

2014-01-01

We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z 330 times weaker than...... expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL...... quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with ≲ 45 counts in the 3-24 keV band, and the other three...

Line Shifts, Broad-line Region Inflow, and the Feeding of Active Galactic Nuclei

Czech Academy of Sciences Publication Activity Database

Gaskell, C. M.; Goosmann, René

2013-01-01

Roč. 769, č. 1 (2013), 30/1-30/10 ISSN 0004-637X R&D Projects: GA MŠk(CZ) LC06014 Institutional research plan: CEZ:AV0Z10030501 Keywords : accretion * accretion disks * black hole physics Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 6.280, year: 2013

Observations of far-infrared line profiles in the Orion-KL region

International Nuclear Information System (INIS)

Crawford, M.K.; Lugten, J.B.; Fitelson, W.; Genzel, R.; Melnick, G.; Harvard-Smithsonian Center for Astrophysics, Cambridge, MA)

1986-01-01

Measurements of several far-infrared emission line profiles in the Orion-KL region are reported. The emission from the CO, OH, and forbidden O I emission lines toward the BN-KL and H2 peak 1 positions probably comes from dense, hot molecular gas in the Orion-KL shock. The CO and forbidden O I lines have similar profiles, suggesting that the high-velocity forbidden O I emission also arises in magnetohydrodynamic cloud shocks. The velocity centroids of the lines are somewhat blueshifted. The far-infrared data thus support the interpretation that the blue asymmetry of the H2 2 micron lines is not mainly due to differential dust extinction, but rather to the kinematics and geometry of the shocked gas in the Orion-KL outflow. The forbidden O I and CO lines, however, have significantly less extreme blueshifted emission than the H2 lines. Both the forbidden O I 63 micron and forbidden C II 158 micron lines have features strongly supporting a common origin near the surface of the Orion molecular cloud. 28 references

THE DEMOGRAPHICS OF BROAD-LINE QUASARS IN THE MASS-LUMINOSITY PLANE. II. BLACK HOLE MASS AND EDDINGTON RATIO FUNCTIONS

Energy Technology Data Exchange (ETDEWEB)

Kelly, Brandon C. [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93107 (United States); Shen, Yue [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, MA 02138 (United States)

2013-02-10

We employ a flexible Bayesian technique to estimate the black hole (BH) mass and Eddington ratio functions for Type 1 (i.e., broad line) quasars from a uniformly selected data set of {approx}58, 000 quasars from the Sloan Digital Sky Survey (SDSS) DR7. We find that the SDSS becomes significantly incomplete at M {sub BH} {approx}< 3 Multiplication-Sign 10{sup 8} M {sub Sun} or L/L {sub Edd} {approx}< 0.07, and that the number densities of Type 1 quasars continue to increase down to these limits. Both the mass and Eddington ratio functions show evidence of downsizing, with the most massive and highest Eddington ratio BHs experiencing Type 1 quasar phases first, although the Eddington ratio number densities are flat at z < 2. We estimate the maximum Eddington ratio of Type 1 quasars in the observable universe to be L/L {sub Edd} {approx} 3. Consistent with our results in Shen and Kelly, we do not find statistical evidence for a so-called sub-Eddington boundary in the mass-luminosity plane of broad-line quasars, and demonstrate that such an apparent boundary in the observed distribution can be caused by selection effect and errors in virial BH mass estimates. Based on the typical Eddington ratio in a given mass bin, we estimate growth times for the BHs in Type 1 quasars and find that they are comparable to or longer than the age of the universe, implying an earlier phase of accelerated (i.e., with higher Eddington ratios) and possibly obscured growth. The large masses probed by our sample imply that most of our BHs reside in what are locally early-type galaxies, and we interpret our results within the context of models of self-regulated BH growth.

The Relationship between Mg ii Broad Emission and Quasar Inclination Angle

Directory of Open Access Journals (Sweden)

Conor Wildy

2017-11-01

Full Text Available Several observed spectral properties of quasars are believed to be influenced by quasar orientation. In this investigation we examine the effect of orientation on the Mg ii line located at 2,798 Å in a sample of 36 radio-loud quasars, with orientation angles having been obtained in a previous study using radio observations. We find no significant relationship between orientation angle and either Mg ii line full-width at half-maximum or equivalent width. The lack of correlation with inclination angle contradicts previous studies which also use radio data as a proxy for inclination angle and suggests the Mg ii emission region does not occupy a disk-like geometry. The lack of correlation with Mg ii equivalent width, however, is reported in at least one previous study. Although the significance is not very strong (86%, there is a possible negative relationship between inclination angle and Fe ii strength which, if true, could explain the Fe ii anti-correlation with [O iii] strength associated with Eigenvector 1. Interestingly, there are objects having almost edge-on inclinations while still exhibiting broad lines. This could be explained by a torus which is either clumpy (allowing sight lines to the central engine or mis-aligned with the accretion disk.

The Relationship between Mg ii Broad Emission and Quasar Inclination Angle

Energy Technology Data Exchange (ETDEWEB)

Wildy, Conor; Czerny, Bozena, E-mail: wildy@cft.edu.pl [Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland)

2017-11-14

Several observed spectral properties of quasars are believed to be influenced by quasar orientation. In this investigation we examine the effect of orientation on the Mg ii line located at 2,798 Å in a sample of 36 radio-loud quasars, with orientation angles having been obtained in a previous study using radio observations. We find no significant relationship between orientation angle and either Mg ii line full-width at half-maximum or equivalent width. The lack of correlation with inclination angle contradicts previous studies which also use radio data as a proxy for inclination angle and suggests the Mg ii emission region does not occupy a disk-like geometry. The lack of correlation with Mg ii equivalent width, however, is reported in at least one previous study. Although the significance is not very strong (86%), there is a possible negative relationship between inclination angle and Fe ii strength which, if true, could explain the Fe ii anti-correlation with [O iii] strength associated with Eigenvector 1. Interestingly, there are objects having almost edge-on inclinations while still exhibiting broad lines. This could be explained by a torus which is either clumpy (allowing sight lines to the central engine) or mis-aligned with the accretion disk.

Emission-line diagnostics of nearby H II regions including interacting binary populations

Science.gov (United States)

Xiao, Lin; Stanway, Elizabeth R.; Eldridge, J. J.

2018-06-01

We present numerical models of the nebular emission from H II regions around young stellar populations over a range of compositions and ages. The synthetic stellar populations include both single stars and interacting binary stars. We compare these models to the observed emission lines of 254 H II regions of 13 nearby spiral galaxies and 21 dwarf galaxies drawn from archival data. The models are created using the combination of the BPASS (Binary Population and Spectral Synthesis) code with the photoionization code CLOUDY to study the differences caused by the inclusion of interacting binary stars in the stellar population. We obtain agreement with the observed emission line ratios from the nearby star-forming regions and discuss the effect of binary-star evolution pathways on the nebular ionization of H II regions. We find that at population ages above 10 Myr, single-star models rapidly decrease in flux and ionization strength, while binary-star models still produce strong flux and high [O III]/H β ratios. Our models can reproduce the metallicity of H II regions from spiral galaxies, but we find higher metallicities than previously estimated for the H II regions from dwarf galaxies. Comparing the equivalent width of H β emission between models and observations, we find that accounting for ionizing photon leakage can affect age estimates for H II regions. When it is included, the typical age derived for H II regions is 5 Myr from single-star models, and up to 10 Myr with binary-star models. This is due to the existence of binary-star evolution pathways, which produce more hot Wolf-Rayet and helium stars at older ages. For future reference, we calculate new BPASS binary maximal starburst lines as a function of metallicity, and for the total model population, and present these in Appendix A.

Synthesis method based on solution regions for planar four bar straight line linkages

International Nuclear Information System (INIS)

Lai Rong, Yin; Cong, Mao; Jian you, Han; Tong, Yang; Juan, Huang

2012-01-01

An analytical method for synthesizing and selecting desired four-bar straight line mechanisms based on solution regions is presented. Given two fixed pivots, the point position and direction of the target straight line, an infinite number of mechanism solutions can be produced by employing this method, both in the general case and all three special cases. Unifying the straight line direction and the displacement from the given point to the instant center into the same form with different angles as parameters, infinite mechanism solutions can be expressed with different solution region charts. The mechanism property graphs have been computed to enable the designers to find out the involved mechanism information more intuitively and avoid aimlessness in selecting optimal mechanisms

Gene mutation in ATM/PI3K region of nasopharyngeal carcinoma cell lines

International Nuclear Information System (INIS)

Wang Hongmei; Wu Xinyao; Xia Yunfei

2002-01-01

Objective: To define the correlation between nasopharyngeal carcinoma (NPC) cell radiosensitivity and gene mutation in the ATM/PI3K coding region. Methods: The gene mutation in the ATM/PI3K region of nasopharyngeal carcinoma cell lines which vary in radiosensitivity, was monitored by reverse transcription-polymerase chain reaction (RT-PCR) and fluorescence-marked ddNTP cycle sequencing technique. Results: No gene mutation was detected in the ATM/PI3K region of either CNE1 or CNE2. Conclusion: Disparity in intrinsic radiosensitivity between different NPC cell lines depends on some other factors and mechanism without being related to ATM/PI3K mutations

Development of Elite BPH-Resistant Wide-Spectrum Restorer Lines for Three and Two Line Hybrid Rice.

Science.gov (United States)

Fan, Fengfeng; Li, Nengwu; Chen, Yunping; Liu, Xingdan; Sun, Heng; Wang, Jie; He, Guangcun; Zhu, Yingguo; Li, Shaoqing

2017-01-01

Hybrid rice has contributed significantly to the world food security. Breeding of elite high-yield, strong-resistant broad-spectrum restorer line is an important strategy for hybrid rice in commercial breeding programs. Here, we developed three elite brown planthopper (BPH)-resistant wide-spectrum restorer lines by pyramiding big-panicle gene Gn8.1 , BPH-resistant genes Bph6 and Bph9 , fertility restorer genes Rf3, Rf4, Rf5 , and Rf6 through molecular marker assisted selection. Resistance analysis revealed that the newly developed restorer lines showed stronger BPH-resistance than any of the single-gene donor parent Luoyang-6 and Luoyang-9. Moreover, the three new restorer lines had broad spectrum recovery capabilities for Honglian CMS, Wild abortive CMS and two-line GMS sterile lines, and higher grain yields than that of the recurrent parent 9,311 under nature field conditions. Importantly, the hybrid crosses also showed good performance for grain yield and BPH-resistance. Thus, the development of elite BPH-resistant wide-spectrum restorer lines has a promising future for breeding of broad spectrum BPH-resistant high-yield varieties.

Diffusion effects on the line intensities of He I and He II in the solar transition region

International Nuclear Information System (INIS)

Shine, R.; Gerola, H.; Linsky, J.L.

1975-01-01

A heuristic treatment of diffusion in the solar chromosphere-corona transition region is developed. Diffusion becomes increasingly important with steeper temperature gradients, in active and quiet regions relative to coronal holes, and with increasing excitation potential. Numerical calculations are made for the resonance lines of He i and He ii and show that diffusion can enhance these lines. Thus the helium lines may appear relatively weak in coronal holes due to a weakening of the enhancement mechanism. Most transition region lines will be less affected by diffusion than He i or He ii

African Journals Online: General Science (broad subject range)

African Journals Online (AJOL)

Items 51 - 86 of 86 ... The Journal of Science and Technology (JUST) aims principally at publishing articles ... basic sciences, public health, social medicine and medical politics. .... The SWJ is a peer review on-line international journal of broad ...

Electron density in the emission-line region of Wolf-Rayet stars

International Nuclear Information System (INIS)

Varshni, Y.P.

1978-01-01

The Inglis-Teller relation, generalized for a hydrogen-like or alkali-like ion with an arbitrary core charge, is used to estimate the electron density in the emission-like region of Wolf-Rayet stars. It is found that the electron density in the region which gives rise to He II emission lines is approximately = 4 x 10 14 cm -3 . (Auth.)

Why is observable radio recombination line emission from galactic HII regions always close to LTE

International Nuclear Information System (INIS)

Shaver, P.A.

1980-01-01

There is no evidence for significant deviations from LTE in single-dish observations of radio recombination line emission from galactic HII regions. This is in agreement with the known properties of HII regions, particularly their density variations and limited range of excitation parameters; the optimum configuration for strong observable non-LTE effects, low electron density and high emission measure, simply does not exist in galactic HII regions, and the observed lines are emitted under near-LTE conditions. Models of the Orion Nebulae and NGC 6604 are presented which fit all available data and show only weak stimulated emission. It is concluded that reliable electron temperatures can indeed be obtained from straightforward analysis of appropriate radio recombination lines. (orig.)

Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission

Energy Technology Data Exchange (ETDEWEB)

Kataoka, J.; /Waseda U., RISE; Stawarz, L.; /JAXA, Sagamihara /Jagiellonian U., Astron. Observ.; Takahashi, Y.; /Waseda U., RISE; Cheung, C.C.; /Natl. Acad. Sci. /Naval Research Lab, Wash., D.C.; Hayashida, M.; /SLAC /Stanford U., HEPL /KIPAC, Menlo Park; Grandi, P.; /Bologna Observ.; Burnett, T.H.; /Washington U., Seattle; Celotti, A.; /SISSA, Trieste; Fegan, S.J.; Fortin, P.; /Ecole Polytechnique; Maeda, K.; Nakamori, T.; /Waseda U., RISE; Taylor, G.B.; /New Mexico U.; Tosti, G.; /INFN, Perugia /Perugia U.; Digel, S.W.; /SLAC /Stanford U., HEPL /KIPAC, Menlo Park; McConville, W.; /NASA, Goddard /Maryland U.; Finke, J.; /Naval Research Lab, Wash., D.C.; D' Ammando, F.; /IASF, Palermo /INAF, Rome

2012-06-07

We report on a detailed investigation of the {gamma}-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed {gamma}-ray emission reveals in addition possible flux variability in both sources. No statistically significant {gamma}-ray detection of the other BLRGs was however found in the considered dataset. Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in {gamma}-rays is the particularly strong nuclear radio flux. This finding, together with the indications of the {gamma}-ray flux variability and a number of other arguments presented, indicate that the GeV emission of BLRGs is most likely dominated by the beamed radiation of relativistic jets observed at intermediate viewing angles. In this paper we also analyzed a comparison sample of high accretion-rate Seyfert 1 galaxies, which can be considered radio-quiet counterparts of BLRGs, and found none were detected in {gamma}-rays. A simple phenomenological hybrid model applied for the broad-band emission of the discussed radio-loud and radio-quiet type 1 active galaxies suggests that the relative contribution of the nuclear jets to the accreting matter is {ge} 1% on average for BLRGs, while {le} 0.1% for Seyfert 1 galaxies.

NuSTAR reveals the Comptonizing corona of the broad-line radio galaxy 3C 382

Energy Technology Data Exchange (ETDEWEB)

Ballantyne, D. R.; Bollenbacher, J. M. [Center for Relativistic Astrophysics, School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Brenneman, L. W. [Harvard-Smithsonian CfA, 60 Garden Street MS-67, Cambridge, MA 02138 (United States); Madsen, K. K.; Baloković, M.; Harrison, F. A.; Walton, D. J. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Boggs, S. E. [Space Science Laboratory, University of California, Berkeley, CA 94720 (United States); Christensen, F. E.; Craig, W. W. [DTU SpaceNational Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Gandhi, P. [Department of Physics, University of Durham, South Road, Durham DH1 3LE (United Kingdom); Hailey, C. J. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Lohfink, A. M. [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Marinucci, A. [Dipartimento di Matematica e Fisica, Università degli Studi Roma Tre, via della Vasca Navale 84, I-00146 Roma (Italy); Markwardt, C. B.; Zhang, W. W. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Stern, D., E-mail: david.ballantyne@physics.gatech.edu [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

2014-10-10

Broad-line radio galaxies (BLRGs) are active galactic nuclei that produce powerful, large-scale radio jets, but appear as Seyfert 1 galaxies in their optical spectra. In the X-ray band, BLRGs also appear like Seyfert galaxies, but with flatter spectra and weaker reflection features. One explanation for these properties is that the X-ray continuum is diluted by emission from the jet. Here, we present two NuSTAR observations of the BLRG 3C 382 that show clear evidence that the continuum of this source is dominated by thermal Comptonization, as in Seyfert 1 galaxies. The two observations were separated by over a year and found 3C 382 in different states separated by a factor of 1.7 in flux. The lower flux spectrum has a photon-index of Γ=1.68{sub −0.02}{sup +0.03}, while the photon-index of the higher flux spectrum is Γ=1.78{sub −0.03}{sup +0.02}. Thermal and anisotropic Comptonization models provide an excellent fit to both spectra and show that the coronal plasma cooled from kT{sub e} = 330 ± 30 keV in the low flux data to 231{sub −88}{sup +50} keV in the high flux observation. This cooling behavior is typical of Comptonizing corona in Seyfert galaxies and is distinct from the variations observed in jet-dominated sources. In the high flux observation, simultaneous Swift data are leveraged to obtain a broadband spectral energy distribution and indicates that the corona intercepts ∼10% of the optical and ultraviolet emitting accretion disk. 3C 382 exhibits very weak reflection features, with no detectable relativistic Fe Kα line, that may be best explained by an outflowing corona combined with an ionized inner accretion disk.

The 2 mrad crossing-angle ILC interaction region and extraction line

CERN Document Server

Appleby, Robert; Bambade, Philip; Dadoun, Olivier; Parker, Brett; Keller, Lewis; Moffeit, Kenneth C; Nosochkov, Yuri; Seryi, Andrei; Spencer, Cherrill M; Carter, John; Napoly, Olivier

2006-01-01

A complete optics design for the 2mrad crossing angle interaction region and extraction line was presented at Snowmass 2005. Since this time, the design task force has been working on developing and improving the performance of the extraction line. The work has focused on optimising the final doublet parameters and on reducing the power losses resulting from the disrupted beam transport. In this paper, the most recent status of the 2mrad layout and the corresponding performance are presented.

Identification of new solar OH lines in the 10--12 micron region

International Nuclear Information System (INIS)

Goldman, A.; Murcray, F.J.; Gillis, J.R.; Murcray, D.G.

1981-01-01

High-resolution (0.02 cm -1 ) infrared solar spectra obtained with a balloon-borne interferometer reveal new solar absorption features, which appear as regularly spaced quartets, in the 825--960 cm -1 region. The lines are interpreted as high N'' (25--33) pure rotation lines of solar OH. An effective amount of approx.8 x 10 15 molecules cm -2 of OH is estimated from the spectra

Time variations of oxygen emission lines and solar wind dynamic parameters in low latitude region

Science.gov (United States)

Jamlongkul, P.; Wannawichian, S.; Mkrtichian, D.; Sawangwit, U.; A-thano, N.

2017-09-01

Aurora phenomenon is an effect of collision between precipitating particles with gyromotion along Earth’s magnetic field and Earth’s ionospheric atoms or molecules. The particles’ precipitation occurs normally around polar regions. However, some auroral particles can reach lower latitude regions when they are highly energetic. A clear emission from Earth’s aurora is mostly from atomic oxygen. Moreover, the sun’s activities can influence the occurrence of the aurora as well. This work studies time variations of oxygen emission lines and solar wind parameters, simultaneously. The emission’s spectral lines were observed by Medium Resolution Echelle Spectrograph (MRES) along with 2.4 meters diameter telescope at Thai National Observatory, Intanon Mountain, Chiang Mai, Thailand. Oxygen (OI) emission lines were calibrated by Dech-Fits spectra processing program and Dech95 2D image processing program. The correlations between oxygen emission lines and solar wind dynamics will be analyzed. This result could be an evidence of the aurora in low latitude region.

Temperature Measurements in the Solar Transition Region Using N III Line Intensity Ratios

Science.gov (United States)

Doron, R.; Doschek, G. A.; Laming, J. M.; Feldman, U.; Bhatia, A. K.

2003-01-01

UV emission from B-like N and O ions a rather rare opportunity for recording spectral lines in a narrow wavelength range that can potentially be used to derive temperatures relevant to the solar transition region. In these ions, the line intensity ratios of the type (2s2p(sup 2) - 2p(sup 3)) / (2s(sup 2)2p - 2s2p(sup 2)) are very sensitive to the electron temperature. Additionally, the lines involving the ratios fall within a range of only - 12 A; in N III the lines fall in the 980 - 992 A range and in O IV in the 780 - 791 A range. In this work, we explore the use of these atomic systems, primarily in N III, for temperature diagnostics of the transition region by analyzing UV spectra obtained by the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer flown on the Solar and Heliospheric Observatory (SOHO). The N III temperature-sensitive line ratios are measured in more than 60 observations. Most of the measured ratios correspond to temperatures in the range 5.7x10(exp 4) - 6.7x10(exp 4) K. This range is considerably lower than the calculated temperature of maximum abundance of N III, which is approx. 7.6x10(exp 4) K. Detailed analysis of the spectra further indicates that the measured ratios are probably somewhat overestimated due to resonant scattering effects in the 2s(sup 2)2p - 2s2p(sup 2) lines and small blends in the 2s2p(sup 2) - 2p3 lines. Actual lower ratios would only increase the disagreement between the ionization balance calculations and present temperature measurements based on a collisional excitation model. In the case of the O IV spectra, we determined that due to the close proximity in wavelength of the weak line (2s2p(sup 2)-2p3 transitions) to a strong Ne VIII line, sufficiently accurate ratio measurements cannot be obtained. Subject headings: atomic data --- atomic processes --- Sun: transition region --- Sun: U V radiation --- techniques: spectroscopic

DISCOVERY OF THE BROAD-LINED TYPE Ic SN 2013cq ASSOCIATED WITH THE VERY ENERGETIC GRB 130427A

Energy Technology Data Exchange (ETDEWEB)

Xu, D.; Krühler, T.; Hjorth, J.; Malesani, D.; Fynbo, J. P. U.; Watson, D. J.; Geier, S. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 København Ø (Denmark); De Ugarte Postigo, A.; Thöne, C. C.; Sánchez-Ramírez, R. [Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomía s/n, E-18008 Granada (Spain); Leloudas, G. [The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Cano, Z.; Jakobsson, P. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, IS-107 Reykjavik (Iceland); Schulze, S. [Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile); Kaper, L. [Astronomical Institute Anton Pannekoek, University of Amsterdam, Science Park 904, NL-1098 XH Amsterdam (Netherlands); Sollerman, J. [The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Cabrera-Lavers, A. [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Cao, C. [Department of Space Science and Physics, Shandong University at Weihai, Weihai, Shandong 264209 (China); Covino, S. [INAF/Brera Astronomical Observatory, via Bianchi 46, I-23807 Merate (Italy); Flores, H., E-mail: dong@dark-cosmology.dk [Laboratoire Galaxies Etoiles Physique et Instrumentation, Observatoire de Paris, 5 place Jules Janssen, F-92195 Meudon (France); and others

2013-10-20

Long-duration gamma-ray bursts (GRBs) at z < 1 are found in most cases to be accompanied by bright, broad-lined Type Ic supernovae (SNe Ic-BL). The highest-energy GRBs are mostly located at higher redshifts, where the associated SNe are hard to detect observationally. Here, we present early and late observations of the optical counterpart of the very energetic GRB 130427A. Despite its moderate redshift, z = 0.3399 ± 0.0002, GRB 130427A is at the high end of the GRB energy distribution, with an isotropic-equivalent energy release of E{sub iso} ∼ 9.6 × 10{sup 53} erg, more than an order of magnitude more energetic than other GRBs with spectroscopically confirmed SNe. In our dense photometric monitoring, we detect excess flux in the host-subtracted r-band light curve, consistent with that expected from an emerging SN, ∼0.2 mag fainter than the prototypical SN 1998bw. A spectrum obtained around the time of the SN peak (16.7 days after the GRB) reveals broad undulations typical of SNe Ic-BL, confirming the presence of an SN, designated SN 2013cq. The spectral shape and early peak time are similar to those of the high expansion velocity SN 2010bh associated with GRB 100316D. Our findings demonstrate that high-energy, long-duration GRBs, commonly detected at high redshift, can also be associated with SNe Ic-BL, pointing to a common progenitor mechanism.

The Frequency of Intrinsic X-Ray Weakness among Broad Absorption Line Quasars

Science.gov (United States)

Liu, Hezhen; Luo, B.; Brandt, W. N.; Gallagher, S. C.; Garmire, G. P.

2018-06-01

We present combined ≈14–37 ks Chandra observations of seven z = 1.6–2.7 broad absorption line (BAL) quasars selected from the Large Bright Quasar Survey (LBQS). These seven objects are high-ionization BAL (HiBAL) quasars, and they were undetected in the Chandra hard band (2–8 keV) in previous observations. The stacking analyses of previous Chandra observations suggested that these seven objects likely contain some candidates for intrinsically X-ray weak BAL quasars. With the new Chandra observations, six targets are detected. We calculate their effective power-law photon indices and hard-band flux weakness, and find that two objects, LBQS 1203+1530 and LBQS 1442–0011, show soft/steep spectral shapes ({{{Γ }}}eff}={2.2}-0.9+0.9 and {1.9}-0.8+0.9) and significant X-ray weakness in the hard band (by factors of ≈15 and 12). We conclude that the two HiBAL quasars are good candidates for intrinsically X-ray weak BAL quasars. The mid-infrared-to-ultraviolet spectral energy distributions of the two candidates are consistent with those of typical quasars. We constrain the fraction of intrinsically X-ray weak active galactic nuclei (AGNs) among HiBAL quasars to be ≈7%–10% (2/29–3/29), and we estimate it is ≈6%–23% (2/35–8/35) among the general BAL quasar population. Such a fraction is considerably larger than that among non-BAL quasars, and we suggest that intrinsically X-ray weak quasars are preferentially observed as BAL quasars. Intrinsically X-ray weak AGNs likely comprise a small minority of the luminous type 1 AGN population, and they should not affect significantly the completeness of these AGNs found in deep X-ray surveys.

DETECTION OF BROAD Hα EMISSION LINES IN THE LATE-TIME SPECTRA OF A HYDROGEN-POOR SUPERLUMINOUS SUPERNOVA

Energy Technology Data Exchange (ETDEWEB)

Yan, Lin; Masci, F. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Quimby, R. [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); Ofek, E.; Gal-Yam, A.; Vreeswijk, P. M.; Leloudas, G.; Cia, A. de; Yaron, O. [Department of Particle Physics and Astrophysics, Faculty of Physics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Mazzali, P. [Astrophysics Research Institute, Liverpool John Moores University, IC2, Liverpool Science Park, 146 Brownlow Hill, Liverpool L3 5RF (United Kingdom); Perley, D. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Cao, Y.; Kulkarni, S. R. [Astronomy Department, California Institute of Technology, Pasadena, CA 91125 (United States); Nugent, P. E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Rebbapragada, Umaa D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Woźniak, P. R., E-mail: lyan@ipac.caltech.edu [Space and Remote Sensing, ISR-2, MS-B244 Los Alamos National Laboratory Los Alamos, NM 87545 (United States)

2015-12-01

iPTF13ehe is a hydrogen-poor superluminous supernova (SLSN) at z = 0.3434, with a slow-evolving light curve and spectral features similar to SN2007bi. It rises in 83–148 days to reach a peak bolometric luminosity of ∼1.3 × 10{sup 44} erg s{sup −1}, then decays slowly at 0.015 mag day{sup −1}. The measured ejecta velocity is ∼ 13,000 km s{sup −1}. The inferred explosion characteristics, such as the ejecta mass (70–220 M{sub ⊙}), and the total radiative and kinetic energy (E{sub rad} ∼ 10{sup 51} erg, E{sub kin} ∼ 2 × 10{sup 53} erg), are typical of slow-evolving H-poor SLSN events. However, the late-time spectrum taken at +251 days (rest, post-peak) reveals a Balmer Hα 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 ∼4500 km s{sup −1} and a ∼300 km s{sup −1} blueward shift relative to the narrow component. We interpret this broad Hα emission with a luminosity of ∼2 × 10{sup 41} erg s{sup −1} as resulting from the interaction between the supernova ejecta and a discrete H-rich shell, located at a distance of ∼4 × 10{sup 16} cm from the explosion site. This interaction causes the rest-frame r-band LC to brighten at late times. The fact that the late-time spectra are not completely absorbed by the shock-ionized H-shell implies that its Thomson scattering optical depth is likely ≤1, thus setting upper limits on the shell mass ≤30 M{sub ⊙}. Of the existing models, a Pulsational Pair Instability supernova model can naturally explain the observed 30 M{sub ⊙} H-shell, ejected from a progenitor star with an initial mass of (95–150) M{sub ⊙} about 40 years ago. We estimate that at least ∼15% of all SLSNe-I may have late-time Balmer emission lines.

Biogas infrastructure from farm-scale to regional scale, line-pack storage in biogas grids

NARCIS (Netherlands)

Hengeveld, Evert Jan

2016-01-01

Biogas infrastructure from farm-scale to regional scale, line-pack storage in biogas grids. The number of local and regional initiatives encouraging the production and use of regional produced energy grows. In these new developments biogas can play a role, as a producer of energy, but also in

The Southern H ii Region Discovery Survey (SHRDS): Pilot Survey

Energy Technology Data Exchange (ETDEWEB)

Brown, C.; Dickey, John M. [School of Physical Sciences, Private Bag 37, University of Tasmania, Hobart, TAS, 7001 (Australia); Jordan, C. [International Centre for Radio Astronomy Research, Curtin University, Perth, WA, 6845 (Australia); Anderson, L. D.; Armentrout, W. P. [Department of Physics and Astronomy, West Virginia University, P.O. Box 6315, Morgantown, WV 26506 (United States); Balser, Dana S.; Wenger, Trey V. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22904 (United States); Bania, T. M. [Institute for Astrophysical Research, Department of Astronomy, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States); Dawson, J. R. [Department of Physics and Astronomy and MQ Research Centre in Astronomy, Astrophysics and Astrophotonics, Macquarie University, NSW, 2109 (Australia); Mc Clure-Griffiths, N. M. [Research School of Astronomy and Astrophysics, The Australian National University, Canberra ACT 2611 (Australia)

2017-07-01

The Southern H ii Region Discovery Survey is a survey of the third and fourth quadrants of the Galactic plane that will detect radio recombination line (RRL) and continuum emission at cm-wavelengths from several hundred H ii region candidates using the Australia Telescope Compact Array. The targets for this survey come from the WISE Catalog of Galactic H ii Regions and were identified based on mid-infrared and radio continuum emission. In this pilot project, two different configurations of the Compact Array Broad Band receiver and spectrometer system were used for short test observations. The pilot surveys detected RRL emission from 36 of 53 H ii region candidates, as well as seven known H ii regions that were included for calibration. These 36 recombination line detections confirm that the candidates are true H ii regions and allow us to estimate their distances.

The Southern H ii Region Discovery Survey (SHRDS): Pilot Survey

International Nuclear Information System (INIS)

Brown, C.; Dickey, John M.; Jordan, C.; Anderson, L. D.; Armentrout, W. P.; Balser, Dana S.; Wenger, Trey V.; Bania, T. M.; Dawson, J. R.; Mc Clure-Griffiths, N. M.

2017-01-01

The Southern H ii Region Discovery Survey is a survey of the third and fourth quadrants of the Galactic plane that will detect radio recombination line (RRL) and continuum emission at cm-wavelengths from several hundred H ii region candidates using the Australia Telescope Compact Array. The targets for this survey come from the WISE Catalog of Galactic H ii Regions and were identified based on mid-infrared and radio continuum emission. In this pilot project, two different configurations of the Compact Array Broad Band receiver and spectrometer system were used for short test observations. The pilot surveys detected RRL emission from 36 of 53 H ii region candidates, as well as seven known H ii regions that were included for calibration. These 36 recombination line detections confirm that the candidates are true H ii regions and allow us to estimate their distances.

The peculiar A star HD 110066: a photographic region line identification study

International Nuclear Information System (INIS)

Adelman, S.J.

1988-01-01

A line identification study of the very sharp-lined peculiar A star HD 110066 has been performed using four high dispersion photographic region spectrograms. New species found include Al I, Si I, S II, Ti I, Co II, Zr II, Cd I, La II, Ce III, Gd III, Dy II, Er II and Tm II. The presence of these species is in accord with the continuity of the magnetic Ap star sequence. (author)

A study of the structure and kinematics of the narrow-line region in Seyfert galaxies

International Nuclear Information System (INIS)

Veilleux, S.

1989-01-01

The results of a high resolution study of the narrow emission line profiles of 16 Seyfert galaxies are presented. It is shown that the line profile parameters published in earlier low resolution studies are sometimes strongly influenced by resolution effects. In spite of these important systematic errors, many of the results derived from low resolution data are confirmed in the high resolution data. The narrow line profiles of Seyfert galaxies have a stronger base relative to core than a Gaussian. Most of the emission lines present a blueward asymmetry in the lower portion of their profile. In some galaxies, the line widths and/or line asymmetries are correlated with the ionization potential and/or critical density of the lines. There is a weak correlation between the line asymmetry and the dust content of the narrow line region (NLR). The large scatter in this relation, the absence of a similar correlation in Seyfert 1 to 1.5 galaxies, and the presence of a blue asymmetry in galaxies with dustfree line-emitting regions suggest that dust obscuration is not the only mechanism responsible for the line asymmetry in active galaxies. An optically-thick disk close to the nucleus is proposed as the other source of line asymmetry. An important result is that the host galaxy is probably playing a role in the kinematics of some of the gas in the NLR. A multicomponent model of the NLR is proposed to explain these results

INTERACTION BETWEEN THE BROAD-LINED TYPE Ic SUPERNOVA 2012ap AND CARRIERS OF DIFFUSE INTERSTELLAR BANDS

International Nuclear Information System (INIS)

Milisavljevic, Dan; Margutti, Raffaella; Crabtree, Kyle N.; Soderberg, Alicia M.; Sanders, Nathan E.; Drout, Maria R.; Kamble, Atish; Chakraborti, Sayan; Kirshner, Robert P.; Foster, Jonathan B.; Fesen, Robert A.; Parrent, Jerod T.; Pickering, Timothy E.; Cenko, S. Bradley; Silverman, Jeffrey M.; Marion, G. H. Howie; Vinko, Jozsef; Filippenko, Alexei V.; Mazzali, Paolo; Maeda, Keiichi

2014-01-01

Diffuse interstellar bands (DIBs) are absorption features observed in optical and near-infrared spectra that are thought to be associated with carbon-rich polyatomic molecules in interstellar gas. However, because the central wavelengths of these bands do not correspond to electronic transitions of any known atomic or molecular species, their nature has remained uncertain since their discovery almost a century ago. Here we report on unusually strong DIBs in optical spectra of the broad-lined Type Ic supernova SN 2012ap that exhibit changes in equivalent width over short (≲ 30 days) timescales. The 4428 Å and 6283 Å DIB features get weaker with time, whereas the 5780 Å feature shows a marginal increase. These nonuniform changes suggest that the supernova is interacting with a nearby source of DIBs and that the DIB carriers possess high ionization potentials, such as small cations or charged fullerenes. We conclude that moderate-resolution spectra of supernovae with DIB absorptions obtained within weeks of outburst could reveal unique information about the mass-loss environment of their progenitor systems and provide new constraints on the properties of DIB carriers

INTERACTION BETWEEN THE BROAD-LINED TYPE Ic SUPERNOVA 2012ap AND CARRIERS OF DIFFUSE INTERSTELLAR BANDS

Energy Technology Data Exchange (ETDEWEB)

Milisavljevic, Dan; Margutti, Raffaella; Crabtree, Kyle N.; Soderberg, Alicia M.; Sanders, Nathan E.; Drout, Maria R.; Kamble, Atish; Chakraborti, Sayan; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Foster, Jonathan B. [Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06520 (United States); Fesen, Robert A.; Parrent, Jerod T. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Lab, Hanover, NH 03755 (United States); Pickering, Timothy E. [Southern African Large Telescope, P.O. Box 9, Observatory 7935, Cape Town (South Africa); Cenko, S. Bradley [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Silverman, Jeffrey M.; Marion, G. H. Howie; Vinko, Jozsef [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Mazzali, Paolo [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5RF (United Kingdom); Maeda, Keiichi, E-mail: dmilisav@cfa.harvard.edu [Department of Astronomy, Kyoto University Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); and others

2014-02-10

Diffuse interstellar bands (DIBs) are absorption features observed in optical and near-infrared spectra that are thought to be associated with carbon-rich polyatomic molecules in interstellar gas. However, because the central wavelengths of these bands do not correspond to electronic transitions of any known atomic or molecular species, their nature has remained uncertain since their discovery almost a century ago. Here we report on unusually strong DIBs in optical spectra of the broad-lined Type Ic supernova SN 2012ap that exhibit changes in equivalent width over short (≲ 30 days) timescales. The 4428 Å and 6283 Å DIB features get weaker with time, whereas the 5780 Å feature shows a marginal increase. These nonuniform changes suggest that the supernova is interacting with a nearby source of DIBs and that the DIB carriers possess high ionization potentials, such as small cations or charged fullerenes. We conclude that moderate-resolution spectra of supernovae with DIB absorptions obtained within weeks of outburst could reveal unique information about the mass-loss environment of their progenitor systems and provide new constraints on the properties of DIB carriers.

High-Performance 1.55-µm Superluminescent Diode Based on Broad Gain InAs/InGaAlAs/InP Quantum Dash Active Region

KAUST Repository

Khan, Mohammed Zahed Mustafa

2014-08-01

We report on the high-performance characteristics from superluminescent diodes (SLDs) based on four-stack InAs/InGaAlAs chirped-barrier thickness quantum dash (Qdash) in a well structure. The active region exhibits a measured broad gain spectrum of 140 nm, with a peak modal gain of ~41 cm-1. The noncoated two-section gainabsorber broad-area and ridge-waveguide device configuration exhibits an output power of > 20 mW and > 12 mW, respectively. The corresponding -3-dB bandwidths span ~82 nm and ~72 nm, with a small spectral ripple of <; 0.2 dB, related largely to the contribution from dispersive height dash ensembles of the highly inhomogeneous active region. These C-L communication band devices will find applications in various cross-disciplinary fields of optical metrology, optical coherent tomography, etc.

DETECTION OF EXTREMELY BROAD WATER EMISSION FROM THE MOLECULAR CLOUD INTERACTING SUPERNOVA REMNANT G349.7+0.2

Energy Technology Data Exchange (ETDEWEB)

Rho, J. [SETI Institute, 189 N. Bernardo Avenue, Mountain View, CA 94043 (United States); Hewitt, J. W. [CRESST/University of Maryland, Baltimore County, Baltimore, MD 21250 (United States); Boogert, A. [SOFIA Science Center, NASA Ames Research Center, MS 232-11, Moffett Field, CA 94035 (United States); Kaufman, M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192-0106 (United States); Gusdorf, A., E-mail: jrho@seti.org, E-mail: john.w.hewitt@nasa.gov, E-mail: aboogert@sofia.usra.edu, E-mail: michael.kaufman@sjsu.edu, E-mail: antoine.gusdorf@lra.ens.fr [LERMA, UMR 8112 du CNRS, Observatoire de Paris, École Normale Suprieure, 24 rue Lhomond, F-75231 Paris Cedex 05 (France)

2015-10-10

We performed Herschel HIFI, PACS, and SPIRE observations toward the molecular cloud interacting supernova remnant G349.7+0.2. An extremely broad emission line was detected at 557 GHz from the ground state transition 1{sub 10}-1{sub 01} of ortho-water. This water line can be separated into three velocity components with widths of 144, 27, and 4 km s{sup −1}. The 144 km s{sup −1} component is the broadest water line detected to date in the literature. This extremely broad line width shows the importance of probing shock dynamics. PACS observations revealed three additional ortho-water lines, as well as numerous high-J carbon monoxide (CO) lines. No para-water lines were detected. The extremely broad water line is indicative of a high velocity shock, which is supported by the observed CO rotational diagram that was reproduced with a J-shock model with a density of 10{sup 4} cm{sup −3} and a shock velocity of 80 km s{sup −1}. Two far-infrared fine-structure lines, [O i] at 145 μm and [C ii] line at 157 μm, are also consistent with the high velocity J-shock model. The extremely broad water line could be simply from short-lived molecules that have not been destroyed in high velocity J-shocks; however, it may be from more complicated geometry such as high-velocity water bullets or a shell expanding in high velocity. We estimate the CO and H{sub 2}O densities, column densities, and temperatures by comparison with RADEX and detailed shock models.

NARROW-LINE-WIDTH UV BURSTS IN THE TRANSITION REGION ABOVE SUNSPOTS OBSERVED BY IRIS

Energy Technology Data Exchange (ETDEWEB)

Hou, Zhenyong; Huang, Zhenghua; Xia, Lidong; Li, Bo; Madjarska, Maria S.; Fu, Hui; Mou, Chaozhou; Xie, Haixia, E-mail: z.huang@sdu.edu.cn, E-mail: xld@sdu.edu.cn [Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai, 264209 Shandong (China)

2016-10-01

Various small-scale structures abound in the solar atmosphere above active regions, playing an important role in the dynamics and evolution therein. We report on a new class of small-scale transition region structures in active regions, characterized by strong emissions but extremely narrow Si iv line profiles as found in observations taken with the Interface Region Imaging Spectrograph (IRIS). Tentatively named as narrow-line-width UV bursts (NUBs), these structures are located above sunspots and comprise one or multiple compact bright cores at sub-arcsecond scales. We found six NUBs in two data sets (a raster and a sit-and-stare data set). Among these, four events are short-lived with a duration of ∼10 minutes, while two last for more than 36 minutes. All NUBs have Doppler shifts of 15–18 km s{sup −1}, while the NUB found in sit-and-stare data possesses an additional component at ∼50 km s{sup −1} found only in the C ii and Mg ii lines. Given that these events are found to play a role in the local dynamics, it is important to further investigate the physical mechanisms that generate these phenomena and their role in the mass transport in sunspots.

TIME DEPENDENT NONEQUILIBRIUM IONIZATION OF TRANSITION REGION LINES OBSERVED WITH IRIS

Energy Technology Data Exchange (ETDEWEB)

Martínez-Sykora, Juan; Pontieu, Bart De; Hansteen, Viggo H. [Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 (United States); Gudiksen, Boris, E-mail: j.m.sykora@astro.uio.no [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway)

2016-01-20

The properties of nonstatistical equilibrium ionization of silicon and oxygen ions are analyzed in this work. We focus on five solar targets (quiet Sun; coronal hole; plage; quiescent active region, AR; and flaring AR) as observed with the Interface Region Imaging Spectrograph (IRIS). IRIS is best suited for this work owing to the high cadence (up to 0.5 s), high spatial resolution (up to 0.″32), and high signal-to-noise ratios for O iv λ1401 and Si iv λ1402. We find that the observed intensity ratio between lines of three times ionized silicon and oxygen ions depends on their total intensity and that this correlation varies depending on the region observed (quiet Sun, coronal holes, plage, or active regions) and on the specific observational objects present (spicules, dynamic loops, jets, microflares, or umbra). In order to interpret the observations, we compare them with synthetic profiles taken from 2D self-consistent radiative MHD simulations of the solar atmosphere, where the statistical equilibrium or nonequilibrium treatment of silicon and oxygen is applied. These synthetic observations show vaguely similar correlations to those in the observations, i.e., between the intensity ratios and their intensities, but only in the nonequilibrium case do we find that (some of) the observations can be reproduced. We conclude that these lines are formed out of statistical equilibrium. We use our time-dependent nonequilibrium ionization simulations to describe the physical mechanisms behind these observed properties.

HIGH-VELOCITY LINE FORMING REGIONS IN THE TYPE Ia SUPERNOVA 2009ig

International Nuclear Information System (INIS)

Marion, G. H.; Foley, Ryan J.; Challis, Peter; Kirshner, Robert P.; Vinko, Jozsef; Wheeler, J. Craig; Silverman, Jeffrey M.; Hsiao, Eric Y.; Brown, Peter J.; Filippenko, Alexei V.; Garnavich, Peter; Landsman, Wayne B.; Parrent, Jerod T.; Pritchard, Tyler A.; Roming, Peter W. A.; Wang, Xiaofeng

2013-01-01

We report measurements and analysis of high-velocity (HVF) (>20,000 km s –1 ) and photospheric absorption features in a series of spectra of the Type Ia supernova (SN) 2009ig obtained between –14 days and +13 days with respect to the time of maximum B-band luminosity (B-max). We identify lines of Si II, Si III, S II, Ca II, and Fe II that produce both HVF and photospheric-velocity (PVF) absorption features. SN 2009ig is unusual for the large number of lines with detectable HVF in the spectra, but the light-curve parameters correspond to a slightly overluminous but unexceptional SN Ia (M B = –19.46 mag and Δm 15 (B) = 0.90 mag). Similarly, the Si II λ6355 velocity at the time of B-max is greater than 'normal' for an SN Ia, but it is not extreme (v Si = 13,400 km s –1 ). The –14 days and –13 days spectra clearly resolve HVF from Si II λ6355 as separate absorptions from a detached line forming region. At these very early phases, detached HVF are prevalent in all lines. From –12 days to –6 days, HVF and PVF are detected simultaneously, and the two line forming regions maintain a constant separation of about 8000 km s –1 . After –6 days all absorption features are PVF. The observations of SN 2009ig provide a complete picture of the transition from HVF to PVF. Most SNe Ia show evidence for HVF from multiple lines in spectra obtained before –10 days, and we compare the spectra of SN 2009ig to observations of other SNe. We show that each of the unusual line profiles for Si II λ6355 found in early-time spectra of SNe Ia correlate to a specific phase in a common development sequence from HVF to PVF

HIGH-REDSHIFT SDSS QUASARS WITH WEAK EMISSION LINES

International Nuclear Information System (INIS)

Diamond-Stanic, Aleksandar M.; Fan Xiaohui; Jiang Linhua; Kim, J. Serena; Schmidt, Gary D.; Smith, Paul S.; Vestergaard, Marianne; Young, Jason E.; Brandt, W. N.; Shemmer, Ohad; Gibson, Robert R.; Schneider, Donald P.; Strauss, Michael A.; Shen Yue; Anderson, Scott F.; Carilli, Christopher L.; Richards, Gordon T.

2009-01-01

We identify a sample of 74 high-redshift quasars (z > 3) with weak emission lines from the Fifth Data Release of the Sloan Digital Sky Survey and present infrared, optical, and radio observations of a subsample of four objects at z > 4. These weak emission-line quasars (WLQs) constitute a prominent tail of the Lyα + N v equivalent width distribution, and we compare them to quasars with more typical emission-line properties and to low-redshift active galactic nuclei with weak/absent emission lines, namely BL Lac objects. We find that WLQs exhibit hot (T ∼ 1000 K) thermal dust emission and have rest-frame 0.1-5 μm spectral energy distributions that are quite similar to those of normal quasars. The variability, polarization, and radio properties of WLQs are also different from those of BL Lacs, making continuum boosting by a relativistic jet an unlikely physical interpretation. The most probable scenario for WLQs involves broad-line region properties that are physically distinct from those of normal quasars.

Raft cultivation area extraction from high resolution remote sensing imagery by fusing multi-scale region-line primitive association features

Science.gov (United States)

Wang, Min; Cui, Qi; Wang, Jie; Ming, Dongping; Lv, Guonian

2017-01-01

In this paper, we first propose several novel concepts for object-based image analysis, which include line-based shape regularity, line density, and scale-based best feature value (SBV), based on the region-line primitive association framework (RLPAF). We then propose a raft cultivation area (RCA) extraction method for high spatial resolution (HSR) remote sensing imagery based on multi-scale feature fusion and spatial rule induction. The proposed method includes the following steps: (1) Multi-scale region primitives (segments) are obtained by image segmentation method HBC-SEG, and line primitives (straight lines) are obtained by phase-based line detection method. (2) Association relationships between regions and lines are built based on RLPAF, and then multi-scale RLPAF features are extracted and SBVs are selected. (3) Several spatial rules are designed to extract RCAs within sea waters after land and water separation. Experiments show that the proposed method can successfully extract different-shaped RCAs from HR images with good performance.

Quasar Black Hole Mass Estimates from High-Ionization Lines: Breaking a Taboo?

Directory of Open Access Journals (Sweden)

Paola Marziani

2017-09-01

Full Text Available Can high ionization lines such as CIV λ 1549 provide useful virial broadening estimators for computing the mass of the supermassive black holes that power the quasar phenomenon? The question has been dismissed by several workers as a rhetorical one because blue-shifted, non-virial emission associated with gas outflows is often prominent in CIV λ 1549 line profiles. In this contribution, we first summarize the evidence suggesting that the FWHM of low-ionization lines like H β and MgII λ 2800 provide reliable virial broadening estimators over a broad range of luminosity. We confirm that the line widths of CIV λ 1549 is not immediately offering a virial broadening estimator equivalent to the width of low-ionization lines. However, capitalizing on the results of Coatman et al. (2016 and Sulentic et al. (2017, we suggest a correction to FWHM CIV λ 1549 for Eddington ratio and luminosity effects that, however, remains cumbersome to apply in practice. Intermediate ionization lines (IP ∼ 20–30 eV; AlIII λ 1860 and SiIII] λ 1892 may provide a better virial broadening estimator for high redshift quasars, but larger samples are needed to assess their reliability. Ultimately, they may be associated with the broad-line region radius estimated from the photoionization method introduced by Negrete et al. (2013 to obtain black hole mass estimates independent from scaling laws.

Broad-band beam buncher

International Nuclear Information System (INIS)

Goldberg, D.A.; Flood, W.S.; Arthur, A.A.; Voelker, F.

1986-01-01

This patent describes a broad-band beam buncher. This beam buncher consists of: a housing adapted to be eacuated, an electron gun in the housing for producing a beam of electrons, buncher means in the housing forming a buncher cavity which has an entrance opening for receiving the electron beam and an exit opening through which the electron beam passes out of the buncher cavity, a drift tube electrode in the buncher cavity and disposed between the entrance opening and the exit opening with first and second gaps between the drift tube electrode and the entrance and exit openings, the drift tube electrode which has a first drift space through which the electron beam passes in traveling between the entrance and exit openings, modulating means for supplying an ultrahigh frequeny modulating signal to the drift tube electrode for producing velocity modulation of the electrons in the electron beam as the electrons pass through the buncher cavity and the drift tube electrode between the entrance opening and the exit opening, drift space means in the housing forming a second drift space for receiving the velocity modulated electron beam from the exit opening, the velocity modulated electron beam being bunched as it passes along the second drift space, the drift space means has a discharge opening through which the electron beam is discharged from the second drift space after being bunched therein, the modulating means containing a signal source for producing an ultrahigh frequency signal, a transmission line connected between the signal source and the drift tube electrode, and terminating means connected to the drift tube electrode for terminating the transmission line in approximately its characteristic impedance to afford a broad response band with minimum 6 variations therein

Optical emission line spectra of Seyfert galaxies and radio galaxies

International Nuclear Information System (INIS)

Osterbrock, D.E.

1978-01-01

Many radio galaxies have strong emission lines in their optical spectra, similar to the emission lines in the spectra of Seyfert galaxies. The range of ionization extends from [O I] and [N I] through [Ne V] and [Fe VII] to [Fe X]. The emission-line spectra of radio galaxies divide into two types, narrow-line radio galaxies whose spectra are indistinguishable from Seyfert 2 galaxies, and broad-line radio galaxies whose spectra are similar to Seyfert 1 galaxies. However on the average the broad-line radio galaxies have steeper Balmer decrements, stronger [O III] and weaker Fe II emission than the Seyfert 1 galaxies, though at least one Seyfert 1 galaxy not known to be a radio source has a spectrum very similar to typical broad-line radio galaxies. Intermediate-type Seyfert galaxies exist that show various mixtures of the Seyfert 1 and Seyfert 2 properties, and the narrow-line or Seyfert 2 property seems to be strongly correlated with radio emission. (Auth.)

Line profile studies of hydrodynamical models of cometary compact H II regions

International Nuclear Information System (INIS)

Zhu, Feng-Yao; Zhu, Qing-Feng

2015-01-01

We simulate the evolution of cometary H II regions based on several champagne flow models and bow shock models, and calculate the profiles of the [Ne II] fine-structure line at 12.81 μm, the H30α recombination line and the [Ne III] fine-structure line at 15.55 μm for these models at different inclinations of 0°, 30° and 60°. We find that the profiles in the bow shock models are generally different from those in the champagne flow models, but the profiles in the bow shock models with lower stellar velocity (≤ 5 km s −1 ) are similar to those in the champagne flow models. In champagne flow models, both the velocity of peak flux and the flux weighted central velocities of all three lines point outward from molecular clouds. In bow shock models, the directions of these velocities depend on the speed of stars. The central velocities of these lines are consistent with the stellar motion in the high stellar speed cases, but they are opposite directions from the stellar motion in the low speed cases. We notice that the line profiles from the slit along the symmetrical axis of the projected 2D image of these models are useful for distinguishing bow shock models from champagne flow models. It is also confirmed by the calculation that the flux weighted central velocity and the line luminosity of the [Ne III] line can be estimated from the [Ne II] line and the H30α line. (paper)

QSOs with narrow emission lines

International Nuclear Information System (INIS)

Baldwin, J.A.; Mcmahon, R.; Hazard, C.; Williams, R.E.

1988-01-01

Observations of two new high-redshift, narrow-lined QSOs (NLQSOs) are presented and discussed together with observations of similar objects reported in the literature. Gravitational lensing is ruled out as a possible means of amplifying the luminosity for one of these objects. It is found that the NLQSOs have broad bases on their emission lines as well as the prominent narrow cores which define this class. Thus, these are not pole-on QSOs. The FWHM of the emission lines fits onto the smoothly falling tail of the lower end of the line-width distribution for complete QSO samples. The equivalent widths of the combined broad and narrow components of the lines are normal for QSOs of the luminosity range under study. However, the NLQSOs do show ionization differences from broader-lined QSOs; most significant, the semiforbidden C III/C IV intensity ratio is unusually low. The N/C abundance ratio in these objects is found to be normal; the Al/C abundance ratio may be quite high. 38 references

H α and H β Raman scattering line profiles of the symbiotic star AG Pegasi

Science.gov (United States)

Lee, Seong-Jae; Hyung, Siek

2018-04-01

The H α and H β line profiles of the symbiotic star AG Pegasi, observed in 1998 September (phase ϕ = 10.24), display top narrow double Gaussian components and bottom broad components (FWHM = 200-400 km s-1). The photoionization model indicates that the ionized zone, responsible for the hydrogen Balmer and Lyman lines, is radiation-bounded, with a hydrogen gas number density of nH ˜ 109.85 cm-3 and a gas temperature of Te = 12 000-15 000 K. We have carried out Monte Carlo simulations to fit the Raman scattering broad wings, assuming that the hydrogen Ly β and Ly γ lines emitted within the radiation-bounded H II zone around a white dwarf have the same double Gaussian line profile shape as the hydrogen Balmer lines. The simulation shows that the scattering H I zones are attached to (or located just outside) the inner H II shells. The best fit to the observed broad H I line profiles indicates that the column density of the scattering neutral zone is NH ≃ 3-5 × 1019 cm-2. We have examined whether the geometrical structure responsible for the observed H α and H β line profiles is a bipolar conical shell structure, consisting of the radiation-bounded ionized zone and the outer material bounded neutral zone. The expanding bipolar structure might be two opposite regions of the common envelope or the outer shell of the Roche lobe around the hot white dwarf, formed through the mass inflows from the giant star and pushed out by the fast winds from the hot white dwarf.

Crowdsourcing Broad Absorption Line Properties and Other Features of Quasar Outflow Using Zooniverse Citizen Science Project Platform

Science.gov (United States)

Crowe, Cassie; Lundgren, Britt; Grier, Catherine

2018-01-01

The Sloan Digital Sky Survey (SDSS) regularly publishes vast catalogs of quasars and other astronomical objects. Previously, the SDSS collaboration has used visual inspection to check quasar redshift validity and flag instances of broad absorption lines (BALs). This information helps researchers to easily single out the quasars with BAL properties and study their outflows and other intervening gas clouds. Due to the ever-growing number of new SDSS quasar observations, visual inspections are no longer possible using previous methods. Currently, BAL information is being determined entirely computationally, and the accuracy of that information is not precisely known. This project uses the Zooniverse citizen science platform to visually inspect quasar spectra for BAL properties, to check the accuracy of the current autonomous methods, and to flag multi-phase outflows and find candidates for in-falling gas into the quasar central engine. The layout and format of a Zooniverse project provides an easier way to inspect and record data on each spectrum and share the workload via crowdsourcing. Work done by the SDSS collaboration members is serving as a beta test for a public project upon the official release of the DR14 quasar catalog by SDSS.

The Size of Narrow Line Region and [OIII] Luminosity Analyzed from ...

Indian Academy of Sciences (India)

Abstract. In this work, we constructed a sample of 4002 quasars from. SDSS DR7 quasar catalogue to calculate the electron density and size of narrow line region. We find that the electron densities are ∼103/cm3, and the sizes are between 27 and 775 pc. We also find that, in the ionization cone, the sizes are tightly ...

A VERY LARGE ARRAY STUDY OF ULTRACOMPACT AND HYPERCOMPACT H II REGIONS FROM 0.7 TO 3.6 cm

International Nuclear Information System (INIS)

Sewilo, M.; Churchwell, E.; Kurtz, S.; Goss, W. M.; Hofner, P.

2011-01-01

We report multi-frequency Very Large Array observations of three massive star formation regions (MSFRs) containing radio continuum components that were identified as broad radio recombination line (RRL) sources and hypercompact (HC) H II region candidates in our previous H92α and H76α study: G10.96+0.01 (component W), G28.20-0.04 (N), and G34.26+0.15 (B). An additional HC H II region candidate, G45.07+0.13, known to have broad H66α and H76α lines, small size, high electron density, and emission measure, was also included. We observed with high spatial resolution (0.''9-2.''3) the H53α, H66α, H76α, and H92α RRLs and the radio continuum at the corresponding wavelengths (0.7-3.6 cm). The motivation for these observations was to obtain RRLs over a range of principal quantum states to look for signatures of pressure broadening and macroscopic velocity structure. We find that pressure broadening contributes significantly to the linewidths, but it is not the sole cause of the broad lines. We compare radio continuum and dust emission distributions and find a good correspondence. We also discuss maser emission and multi-wavelength observations reported in the literature for these MSFRs.

ESSEA On-Line Courses and the WestEd Eisenhower Regional Consortium (WERC)

Science.gov (United States)

Rognier, E.

2001-12-01

The WestEd Eisenhower Regional Consortium (WERC) is in its second year of offering two Earth Systems Science On-line Graduate courses from IGES - one for High School teachers, and one for Middle School teachers. These high-quality courses support WERC's commitment to "supporting increased scientific and mathematical literacy among our nation's youth through services and other support aimed at enhancing the efforts of those who provide K-12 science and mathematics education." WERC has been able to use its EdGateway online community network to offer these courses to environmental education and science teachers nationwide. Through partnerships with the North American Association for Environmental Education (NAAEE), the National Environmental Education Advancement Project (NEEAP), and other regional, state and local science and environmental education organizations, WERC has a broad reach in connecting with science educators nationwide. WERC manages several state and national listservs, which enable us to reach thousands of educators with information about the courses. EdGateway also provides a private online community in which we offer the courses. WERC partners with two Master Teachers from Utah, who facilitate the courses, and with the Center for Science and Mathematics Education at Weber State University, who provides low-cost graduate credit for the courses. Our students have included classroom teachers from upper elementary through high school, community college science teachers, and environmental science center staff who provide inservice for teachers. Educators from Hawaii to New Jersey have provided diverse personal experiences of Earth Systems Science events, and add richness to the online discussions. Two Earth Science Experts, Dr. Rick Ford from Weber State University, and Dr. Art Sussman from WestEd also contribute to the high caliber of learning the students experience in the courses. (Dr. Sussman's book, Dr. Art's Guide to Planet Earth, is used as one of

The dependence of C IV broad absorption line properties on accompanying Si IV and Al III absorption: relating quasar-wind ionization levels, kinematics, and column densities

Energy Technology Data Exchange (ETDEWEB)

Filiz Ak, N.; Brandt, W. N.; Schneider, D. P.; Trump, J. R. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele Street, Toronto, Ontario M3J 1P3 (Canada); Anderson, S. F. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Hamann, F. [Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Pâris, I. [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Petitjean, P. [Institut d' Astrophysique de Paris, Universite Paris 6, F-75014 Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Shen, Yue [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); York, Don, E-mail: nfilizak@astro.psu.edu [Department of Astronomy and Astrophysics, The University of Chicago, Chicago, IL 60637 (United States)

2014-08-20

We consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the line of sight intercepts at least some lower ionization gas. We derive a number of observational results for C IV BALs separated according to the presence or absence of accompanying lower ionization transitions, including measurements of composite profile shapes, equivalent width (EW), characteristic velocities, composite variation profiles, and EW variability. We also measure the correlations between EW and fractional-EW variability for C IV, Si IV, and Al III. Our measurements reveal the basic correlated changes between ionization level, kinematics, and column density expected in accretion-disk wind models; e.g., lines of sight including lower ionization material generally show deeper and broader C IV troughs that have smaller minimum velocities and that are less variable. Many C IV BALs with no accompanying Si IV or Al III BALs may have only mild or no saturation.

Radio/X-ray monitoring of the broad-line radio galaxy 3C 382. High-energy view with XMM-Newtonand NuSTAR

Science.gov (United States)

Ursini, F.; Petrucci, P.-O.; Matt, G.; Bianchi, S.; Cappi, M.; Dadina, M.; Grandi, P.; Torresi, E.; Ballantyne, D. R.; De Marco, B.; De Rosa, A.; Giroletti, M.; Malzac, J.; Marinucci, A.; Middei, R.; Ponti, G.; Tortosa, A.

2018-05-01

We present the analysis of five joint XMM-Newton/NuSTARobservations, 20 ks each and separated by 12 days, of the broad-line radio galaxy 3C 382. The data were obtained as part of a campaign performed in September-October 2016 simultaneously with VLBA. The radio data and their relation with the X-ray ones will be discussed in a following paper. The source exhibits a moderate flux variability in the UV/X-ray bands, and a limited spectral variability especially in the soft X-ray band. In agreement with past observations, we find the presence of a warm absorber, an iron Kα line with no associated Compton reflection hump, and a variable soft excess well described by a thermal Comptonization component. The data are consistent with a "two-corona" scenario, in which the UV emission and soft excess are produced by a warm (kT ≃ 0.6 keV), optically thick (τ ≃ 20) corona consistent with being a slab fully covering a nearly passive accretion disc, while the hard X-ray emission is due to a hot corona intercepting roughly 10% of the soft emission. These results are remarkably similar to those generally found in radio-quiet Seyferts, thus suggesting a common accretion mechanism.

Marketing plan for Pharmacare product line in the Moscow region Case Oriola-KD

OpenAIRE

Mashkilleyson, Peter

2012-01-01

The thesis was commissioned by Oriola-KD. It deals with a marketing plan for a product line called Pharmacare. The product line will be launched in 2012 in the Moscow region in the Russian Federation. The purpose of this thesis was to acquire useful information about the Moscow market for the target company and produce a marketing plan that they can implement. The research question was how to create an effective marketing plan and what it entails. The literary review consisted of the theo...

Fingerprinting of cell lines by directed amplification of minisatellite-region DNA (DAMD

Directory of Open Access Journals (Sweden)

Silva L.M.

2001-01-01

Full Text Available The development of in vitro propagation of cells has been an extraordinary technical advance for several biological studies. The correct identification of the cell line used, however, is crucial, as a mistaken identity or the presence of another contaminating cell may lead to invalid and/or erroneous conclusions. We report here the application of a DNA fingerprinting procedure (directed amplification of minisatellite-region DNA, developed by Heath et al. [Nucleic Acids Research (1993 21: 5782-5785], to the characterization of cell lines. Genomic DNA of cells in culture was extracted and amplified by PCR in the presence of VNTR core sequences, and the amplicons were separated by agarose gel electrophoresis. After image capture with a digital camera, the banding profiles obtained were analyzed using a software (AnaGel specially developed for the storage and analysis of electrophoretic fingerprints. The fingerprints are useful for construction of a data base for identification of cell lines by comparison to reference profiles as well as comparison of similar lines from different sources and periodic follow-up of cells in culture.

A DEEP X-RAY VIEW OF THE BARE AGN ARK 120. I. REVEALING THE SOFT X-RAY LINE EMISSION

Energy Technology Data Exchange (ETDEWEB)

Reeves, J. N.; Braito, V. [Center for Space Science and Technology, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States); Porquet, D. [Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, F-67000 Strasbourg (France); Nardini, E. [Astrophysics Group, School of Physical and Geographical Sciences, Keele University, Keele, Staffordshire, ST5 5BG (United Kingdom); Lobban, A. [Dept of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Turner, T. J., E-mail: jreeves@umbc.edu, E-mail: j.n.reeves@keele.ac.uk [Department of Physics, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States)

2016-09-10

The Seyfert 1 galaxy Ark 120 is a prototype example of the so-called class of bare nucleus active galactic nuclei (AGNs), whereby there is no known evidence for the presence of ionized gas along the direct line of sight. Here deep (>400 ks exposure), high-resolution X-ray spectroscopy of Ark 120 is presented from XMM-Newton observations that were carried out in 2014 March, together with simultaneous Chandra /High Energy Transmission Grating exposures. The high-resolution spectra confirmed the lack of intrinsic absorbing gas associated with Ark 120, with the only X-ray absorption present originating from the interstellar medium (ISM) of our own Galaxy, with a possible slight enhancement of the oxygen abundance required with respect to the expected ISM values in the solar neighborhood. However, the presence of several soft X-ray emission lines are revealed for the first time in the XMM-Newton RGS spectrum, associated with the AGN and arising from the He- and H-like ions of N, O, Ne, and Mg. The He-like line profiles of N, O, and Ne appear velocity broadened, with typical FWHMs of ∼5000 km s{sup −1}, whereas the H-like profiles are unresolved. From the clean measurement of the He-like triplets, we deduce that the broad lines arise from a gas of density n {sub e} ∼ 10{sup 11} cm{sup −3}, while the photoionization calculations infer that the emitting gas covers at least 10% of 4 π steradian. Thus the broad soft X-ray profiles appear coincident with an X-ray component of the optical–UV broad-line region on sub-parsec scales, whereas the narrow profiles originate on larger parsec scales, perhaps coincident with the AGN narrow-line region. The observations show that Ark 120 is not intrinsically bare and substantial X-ray-emitting gas exists out of our direct line of sight toward this AGN.

Spectral properties of X-ray selected narrow emission line galaxies

Science.gov (United States)

Romero-Colmenero, E.

1998-03-01

This thesis reports a study of the X-ray and optical properties of two samples of X-ray selected Narrow Emission Line Galaxies (NELGs), and their comparison with the properties of broad line Active Galactic Nuclei (AGN). One sample (18 NELGs) is drawn from the ROSAT International X-ray Optical Survey (RIXOS), the other (19 NELGs and 33 AGN) from the ROSAT UK Deep Survey. ROSAT multi-channel X-ray spectra have been extracted and fitted with power-law, bremsstrahlung and black body models for the brighter RIXOS sources. In most cases, power-law and bremsstrahlung models provide the best results. The average spectral energy index, alpha, of the RIXOS NELGs is 0.96 +/- 0.07, similar to that of AGN (alpha~1). For the fainter RIXOS NELGs, as well as for all the UK Deep Survey sources, counts in three spectral bands have been extracted and fitted with a power-law model, assuming the Galactic value for N_H. The brighter RIXOS sources demonstrated that the results obtained by these two different extraction and fitting procedures provide consistent results. Two average X-ray spectra, one for the NELGs and another for the AGN, were created from the UK Deep Survey sources. The power-law slope of the average NELG is alpha = 0.45 +/- 0.09, whilst that of the AGN is alpha = 0.96 +/- 0.03. ROSAT X-ray surveys have shown that the fractional surface density of NELGs increases with respect to AGN at faint fluxes (case for NELGs to be major contributors to the XRB at the fainter fluxes. The analysis of optical spectroscopy, obtained on La Palma and Hawaii, shows that NELGs form a very heterogeneous group, made up of a mixture of Seyfert 2, LINER and HII-region like galaxies. Seyfert 2 galaxies are found to possess in general the steepest X-ray slopes. Ways to explain this in the context of the unified model of AGN are discussed. The FWHM of some emission lines (Halpha, Hbeta, [NII]) in the NELGs appears to increase with steepening X-ray spectral slope. In the case of the Balmer lines

Study of NH3 Line Intensities in the THz and Far-IR Region

Science.gov (United States)

Yu, Shanshan

Ammonia (NH3) exists in the interstellar medium, late-type stars and giant planets of our solar system. Its temperature and abundance profiles in these environments, which are derived with its line parameters as fixed input , are commonly used to provide constraints on retrieving minor species. Therefore NH3 line parameters are essential for interpreting astrophysical and planetary spectra from Herschel, SOFIA, ALMA and JWST. However, our work under a predecessor grant with the APRA program revealed significant deficiencies in NH3 intensities in the terahertz and FIR region, including some weak Delta(K)=3 forbidden transitions predicted to be 100 times stronger. The Delta(K)=3 transitions are the ones connecting levels with different K values and therefore the only way other than collisions and l-doubled states to excite NH3 to K>0 levels. Their intensities have to be corrected to explain the observed high K excitation, such as the detection of NH3 (J,K) = (1,1), (2,2)&(14,14) and (18,18) transitions toward the galactic center star forming region Sgr B2, and to provide insights into the radiative- transfer vs. collision excitation mechanics of interstellar NH3. This proposal will remedy the serious deficiencies in the current databases involving NH3 line parameters in the terahertz and FIR region. We will target transitions with intensities greater than 10^{-23} cm-1/ (molecule/cm2) at 296 K, which will be among new astrophysical detections made by SOFIA, ALMA and JWST, and are 1000 times weaker than the strongest ground state transitions. We will retrieve new positions and intensities from existing laboratory spectra, use them to evaluate the current databases and ab initio calculations, and repair the line positions and intensities by replacing poorly calculated values with our new measurements. The proposed research will result in (1) a validated linelist containing the positions, intensities and lower state energies for the very important Delta(K)=3 NH3 FIR

Properties of Narrow line Seyfert 1 galaxies

Science.gov (United States)

Rakshit, Suvendu; Stalin, Chelliah Subramonian; Chand, Hum; Zhang, Xue-Guang

2018-04-01

Narrow line Seyfert 1 (NLSy1) galaxies constitute a class of active galactic nuclei characterized by the full width at half maximum (FWHM) of the Hα broad emission line 10 pixel-1. A strong correlation between the Hα and Hα emission lines is found both in the FWHM and flux. The nuclear continuum luminosity is found to be strongly correlated with the luminosity of Hα, Hα and [O III] emission lines. The black hole mass in NLSy1 galaxies is lower compared to their broad line counterparts. Compared to BLSy1 galaxies, NLSy1 galaxies have a stronger FeII emission and a higher Eddington ratio that place them in the extreme upper right corner of the R4570 - λEdd diagram. The distribution of the radio-loudness parameter (R) in NLSy1 galaxies drops rapidly at R>10 compared to the BLSy1 galaxies that have powerful radio jets. The soft X-ray photon index in NLSy1 galaxies is on average higher (2.9 ± 0.9) than BLSy1 galaxies (2.4 ± 0.8). It is anti-correlated with the Hα width but correlated with the FeII strength. NLSy1 galaxies on average have a lower amplitude of optical variability compared to their broad lines counterparts. These results suggest Eddington ratio as the main parameter that drives optical variability in these sources.

Genome-wide characterization of genetic variants and putative regions under selection in meat and egg-type chicken lines.

Science.gov (United States)

Boschiero, Clarissa; Moreira, Gabriel Costa Monteiro; Gheyas, Almas Ara; Godoy, Thaís Fernanda; Gasparin, Gustavo; Mariani, Pilar Drummond Sampaio Corrêa; Paduan, Marcela; Cesar, Aline Silva Mello; Ledur, Mônica Corrêa; Coutinho, Luiz Lehmann

2018-01-25

Meat and egg-type chickens have been selected for several generations for different traits. Artificial and natural selection for different phenotypes can change frequency of genetic variants, leaving particular genomic footprints throghtout the genome. Thus, the aims of this study were to sequence 28 chickens from two Brazilian lines (meat and white egg-type) and use this information to characterize genome-wide genetic variations, identify putative regions under selection using Fst method, and find putative pathways under selection. A total of 13.93 million SNPs and 1.36 million INDELs were identified, with more variants detected from the broiler (meat-type) line. Although most were located in non-coding regions, we identified 7255 intolerant non-synonymous SNPs, 512 stopgain/loss SNPs, 1381 frameshift and 1094 non-frameshift INDELs that may alter protein functions. Genes harboring intolerant non-synonymous SNPs affected metabolic pathways related mainly to reproduction and endocrine systems in the white-egg layer line, and lipid metabolism and metabolic diseases in the broiler line. Fst analysis in sliding windows, using SNPs and INDELs separately, identified over 300 putative regions of selection overlapping with more than 250 genes. For the first time in chicken, INDEL variants were considered for selection signature analysis, showing high level of correlation in results between SNP and INDEL data. The putative regions of selection signatures revealed interesting candidate genes and pathways related to important phenotypic traits in chicken, such as lipid metabolism, growth, reproduction, and cardiac development. In this study, Fst method was applied to identify high confidence putative regions under selection, providing novel insights into selection footprints that can help elucidate the functional mechanisms underlying different phenotypic traits relevant to meat and egg-type chicken lines. In addition, we generated a large catalog of line-specific and common

CHEERS Results from NGC 3393. II. Investigating the Extended Narrow-line Region Using Deep Chandra Observations and Hubble Space Telescope Narrow-line Imaging

Energy Technology Data Exchange (ETDEWEB)

Maksym, W. Peter; Fabbiano, Giuseppina; Elvis, Martin; Karovska, Margarita; Paggi, Alessandro; Raymond, John [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Wang, Junfeng [Department of Astronomy, Physics Building, Xiamen University Xiamen, Fujian, 361005 (China); Storchi-Bergmann, Thaisa, E-mail: walter.maksym@cfa.harvard.edu [Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, IF, CP 15051, 91501-970 Porto Alegre, RS (Brazil)

2017-07-20

The CHandra Extended Emission Line Region Survey (CHEERS) is an X-ray study of nearby active galactic nuclei (AGNs) designed to take full advantage of Chandra 's unique angular resolution by spatially resolving feedback signatures and effects. In the second paper of a series on CHEERS target NGC 3393, we examine deep high-resolution Chandra images and compare them with Hubble Space Telescope narrow-line images of [O iii], [S ii], and H α , as well as previously unpublished mid-ultraviolet (MUV) images. The X-rays provide unprecedented evidence that the S-shaped arms that envelope the nuclear radio outflows extend only ≲0.″2 (≲50 pc) across. The high-resolution multiwavelength data suggest that the extended narrow-line region is a complex multiphase structure in the circumnuclear interstellar medium (ISM). Its ionization structure is highly stratified with respect to outflow-driven bubbles in the bicone and varies dramatically on scales of ∼10 pc. Multiple findings show likely contributions from shocks to the feedback in regions where radio outflows from the AGN most directly influence the ISM. These findings include H α evidence for gas compression and extended MUV emission and are in agreement with existing STIS kinematics. Extended filamentary structure in the X-rays and optical suggests the presence of an undetected plasma component, whose existence could be tested with deeper radio observations.

CHEERS Results from NGC 3393. II. Investigating the Extended Narrow-line Region Using Deep Chandra Observations and Hubble Space Telescope Narrow-line Imaging

Science.gov (United States)

Maksym, W. Peter; Fabbiano, Giuseppina; Elvis, Martin; Karovska, Margarita; Paggi, Alessandro; Raymond, John; Wang, Junfeng; Storchi-Bergmann, Thaisa

2017-07-01

The CHandra Extended Emission Line Region Survey (CHEERS) is an X-ray study of nearby active galactic nuclei (AGNs) designed to take full advantage of Chandra's unique angular resolution by spatially resolving feedback signatures and effects. In the second paper of a series on CHEERS target NGC 3393, we examine deep high-resolution Chandra images and compare them with Hubble Space Telescope narrow-line images of [O III], [S II], and Hα, as well as previously unpublished mid-ultraviolet (MUV) images. The X-rays provide unprecedented evidence that the S-shaped arms that envelope the nuclear radio outflows extend only ≲0.″2 (≲50 pc) across. The high-resolution multiwavelength data suggest that the extended narrow-line region is a complex multiphase structure in the circumnuclear interstellar medium (ISM). Its ionization structure is highly stratified with respect to outflow-driven bubbles in the bicone and varies dramatically on scales of ˜10 pc. Multiple findings show likely contributions from shocks to the feedback in regions where radio outflows from the AGN most directly influence the ISM. These findings include Hα evidence for gas compression and extended MUV emission and are in agreement with existing STIS kinematics. Extended filamentary structure in the X-rays and optical suggests the presence of an undetected plasma component, whose existence could be tested with deeper radio observations.

CHEERS Results from NGC 3393. II. Investigating the Extended Narrow-line Region Using Deep Chandra Observations and Hubble Space Telescope Narrow-line Imaging

International Nuclear Information System (INIS)

Maksym, W. Peter; Fabbiano, Giuseppina; Elvis, Martin; Karovska, Margarita; Paggi, Alessandro; Raymond, John; Wang, Junfeng; Storchi-Bergmann, Thaisa

2017-01-01

The CHandra Extended Emission Line Region Survey (CHEERS) is an X-ray study of nearby active galactic nuclei (AGNs) designed to take full advantage of Chandra 's unique angular resolution by spatially resolving feedback signatures and effects. In the second paper of a series on CHEERS target NGC 3393, we examine deep high-resolution Chandra images and compare them with Hubble Space Telescope narrow-line images of [O iii], [S ii], and H α , as well as previously unpublished mid-ultraviolet (MUV) images. The X-rays provide unprecedented evidence that the S-shaped arms that envelope the nuclear radio outflows extend only ≲0.″2 (≲50 pc) across. The high-resolution multiwavelength data suggest that the extended narrow-line region is a complex multiphase structure in the circumnuclear interstellar medium (ISM). Its ionization structure is highly stratified with respect to outflow-driven bubbles in the bicone and varies dramatically on scales of ∼10 pc. Multiple findings show likely contributions from shocks to the feedback in regions where radio outflows from the AGN most directly influence the ISM. These findings include H α evidence for gas compression and extended MUV emission and are in agreement with existing STIS kinematics. Extended filamentary structure in the X-rays and optical suggests the presence of an undetected plasma component, whose existence could be tested with deeper radio observations.

BROAD Lyα EMISSION FROM THREE NEARBY BL LACERTAE OBJECTS

International Nuclear Information System (INIS)

Stocke, John T.; Danforth, Charles W.; Perlman, Eric S.

2011-01-01

We present far-UV HST/COS spectra of four nearby BL Lac objects. BL Lac spectra are dominated by a smooth, power-law continuum which arises in a relativistic jet. However, the spectra are not necessarily featureless; weak, broad- and/or narrow-line emission is sometimes seen in high-quality optical spectra. We present detections of Lyα emission in HST/COS spectra of Mrk 421 (z = 0.030) and PKS 2005-489 (z = 0.071) as well as an archival HST/GHRS observation of Mrk 501 (z = 0.0337). Archival HST/STIS observations of PKS 2155-304 (z = 0.116) show no Lyα emission to a very low upper limit. Using the assumption that the broad-line region (BLR) clouds are symmetrically placed around the active galactic nucleus (AGN), we use these measured Lyα emission features to constrain either the relativistic Γ values for the ionizing continuum produced by the jet (in the ionization-bounded case) or the mass of warm gas (in the density-bounded case). While realistic Γ values can be obtained for all four cases, the values for Mrk 421 and PKS 2155-304 are high enough to suggest that covering factors of BLR clouds of ∼1%-2% might be required to provide consistency with earlier values of Doppler boosting and viewing angles suggested for this class of BL Lacs. This discrepancy also exists in the case of M 87, where the amount of Doppler boosting in our direction is expected to be minimal, again suggestive of a small covering factor of BLR clouds. If, as these small covering factors might suggest, the assumptions of a density-bounded model could be more correct, then the observed Lyα luminosities require that BL Lac/FR 1 nuclei possess very little warm gas (10 -4 to 10 -5 M sun ) as suggested by Guilbert et al. If these clouds are in pressure balance with a hotter (∼10 6 K) gas, the BLR contains too little mass to power the AGN by accretion alone.

Singular surfaces in the open field line region of a diverted tokamak

International Nuclear Information System (INIS)

Reiman, A.

1996-01-01

The structure of the open field lines of a slightly nonaxisymmetric, poloidally diverted tokamak is explored by numerical integration of the field line equations for a simple model field. In practice, the nonaxisymmetry could be produced self-consistently by the nonlinear evolution of a free-boundary magnetohydrodynamic (MHD) mode, or it could be produced by field errors, or it could be imposed externally by design. In the presence of a nonaxisymmetric perturbation, the tokamak is shown to develop open field line regions of differing topology separated by singular surfaces. It is argued that the singular surfaces can be expected to play a role analogous to that of rational toroidal flux surfaces, in terms of constraining ideal MHD perturbations and thus constraining the free-energy that can be tapped by ideal MHD instabilities. The possibility of active control of free-boundary instabilities by means of currents driven on the open singular surfaces, which are directly accessible from the divertor plates, is discussed. copyright 1996 American Institute of Physics

CONSTRAINING JET PRODUCTION SCENARIOS BY STUDIES OF NARROW-LINE RADIO GALAXIES

Energy Technology Data Exchange (ETDEWEB)

Sikora, Marek [Nicolaus Copernicus Astronomical Center, Bartycka 18, 00-716 Warsaw (Poland); Stasinska, Grazyna [LUTH, Observatoire de Paris, CNRS, Universite Paris Diderot, Place Jules Janssen, F-92190 Meudon (France); Koziel-Wierzbowska, Dorota [Astronomical Observatory, Jagiellonian University, ul. Orla 171, 30-244 Krakow (Poland); Madejski, Greg M. [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305 (United States); Asari, Natalia V., E-mail: sikora@camk.edu.pl [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)

2013-03-01

We study a large sample of narrow-line radio galaxies (NLRGs) with extended radio structures. Using 1.4 GHz radio luminosities L {sub 1.4}, narrow optical emission line luminosities L {sub [OIII]} and L{sub H{sub {alpha}}}, as well as black hole masses M {sub BH} derived from stellar velocity dispersions measured from the optical spectra obtained with the Sloan Digital Sky Survey, we find that (1) NLRGs cover about four decades of the Eddington ratio, {lambda} {identical_to} L {sub bol}/L {sub Edd}{proportional_to}L {sub line}/M {sub BH}; (2) L {sub 1.4}/M {sub BH} strongly correlates with {lambda}; and (3) radio loudness, R{identical_to}L{sub 1.4}/L{sub line}, strongly anti-correlates with {lambda}. A very broad range of the Eddington ratio indicates that the parent population of NLRGs includes both radio-loud quasars (RLQs) and broad-line radio galaxies (BLRGs). The correlations they obey and their high jet production efficiencies favor a jet production model which involves the so-called magnetically choked accretion scenario. In this model, production of the jet is dominated by the Blandford-Znajek mechanism, and the magnetic fields in the vicinity of the central black hole are confined by the ram pressure of the accretion flow. Since large net magnetic flux accumulated in central regions of the accretion flow required by the model can take place only via geometrically thick accretion, we speculate that the massive, 'cold' accretion events associated with luminous emission-line active galactic nucleus can be accompanied by an efficient jet production only if preceded by a hot, very sub-Eddington accretion phase.

Nustar Reveals an Intrinsically X-ray Weak Broad Absorption Line Quasar in the Ultraluminous Infrared Galaxy Markarian 231

Science.gov (United States)

Teng, Stacy H.; Brandt. W. N.; Harrison, F. A.; Luo, B.; Alexander, D. M.; Bauer, F. E.; Boggs, S. E.; Christensen, F. E.; Comastri, A.; Craig, W. W.;

Unshifted Metastable He I* Mini-broad Absorption Line System in the Narrow-line Type 1 Quasar SDSS J080248.18+551328.9

Science.gov (United States)

Ji, Tuo; Zhou, Hongyan; Jiang, Peng; Wang, Tinggui; Ge, Jian; Wang, Huiyuan; Komossa, S.; Hamann, Fred; Zuther, Jens; Liu, Wenjuan; Lu, Honglin; Zuo, Wenwen; Yang, Chenwei; Yuan, Weimin

2015-02-01

We report the identification of an unusual absorption-line system in the quasar SDSS J080248.18+551328.9 and present a detailed study of the system, incorporating follow-up optical and near-IR spectroscopy. A few tens of absorption lines are detected, including He I*, Fe II*, and Ni II*, which arise from metastable or excited levels, as well as resonant lines in Mg I, Mg II, Fe II, Mn II, and Ca II. All of the isolated absorption lines show the same profile of width Δv ~ 1500 km s-1 centered at a common redshift as that of the quasar emission lines, such as [O II], [S II], and hydrogen Paschen and Balmer series. With narrow Balmer lines, strong optical Fe II multiplets, and weak [O III] doublets, its emission-line spectrum is typical for that of a narrow-line Seyfert 1 galaxy (NLS1). We have derived reliable measurements of the gas-phase column densities of the absorbing ions/levels. Photoionization modeling indicates that the absorber has a density of n H ~ (1.0-2.5) × 105 cm-3 and a column density of N H ~ (1.0-3.2) × 1021 cm-2 and is located at R ~100-250 pc from the central supermassive black hole. The location of the absorber, the symmetric profile of the absorption lines, and the coincidence of the absorption- and emission-line centroid jointly suggest that the absorption gas originates from the host galaxy and is plausibly accelerated by stellar processes, such as stellar winds and/or supernova explosions. The implications for the detection of such a peculiar absorption-line system in an NLS1 are discussed in the context of coevolution between supermassive black hole growth and host galaxy buildup.

Assessing regional and interspecific variation in threshold responses of forest breeding birds through broad scale analyses.

Directory of Open Access Journals (Sweden)

Yntze van der Hoek

Full Text Available BACKGROUND: Identifying persistence and extinction thresholds in species-habitat relationships is a major focal point of ecological research and conservation. However, one major concern regarding the incorporation of threshold analyses in conservation is the lack of knowledge on the generality and transferability of results across species and regions. We present a multi-region, multi-species approach of modeling threshold responses, which we use to investigate whether threshold effects are similar across species and regions. METHODOLOGY/PRINCIPAL FINDINGS: We modeled local persistence and extinction dynamics of 25 forest-associated breeding birds based on detection/non-detection data, which were derived from repeated breeding bird atlases for the state of Vermont. We did not find threshold responses to be particularly well-supported, with 9 species supporting extinction thresholds and 5 supporting persistence thresholds. This contrasts with a previous study based on breeding bird atlas data from adjacent New York State, which showed that most species support persistence and extinction threshold models (15 and 22 of 25 study species respectively. In addition, species that supported a threshold model in both states had associated average threshold estimates of 61.41% (SE = 6.11, persistence and 66.45% (SE = 9.15, extinction in New York, compared to 51.08% (SE = 10.60, persistence and 73.67% (SE = 5.70, extinction in Vermont. Across species, thresholds were found at 19.45-87.96% forest cover for persistence and 50.82-91.02% for extinction dynamics. CONCLUSIONS/SIGNIFICANCE: Through an approach that allows for broad-scale comparisons of threshold responses, we show that species vary in their threshold responses with regard to habitat amount, and that differences between even nearby regions can be pronounced. We present both ecological and methodological factors that may contribute to the different model results, but propose that

Assessing regional and interspecific variation in threshold responses of forest breeding birds through broad scale analyses.

Science.gov (United States)

van der Hoek, Yntze; Renfrew, Rosalind; Manne, Lisa L

2013-01-01

Identifying persistence and extinction thresholds in species-habitat relationships is a major focal point of ecological research and conservation. However, one major concern regarding the incorporation of threshold analyses in conservation is the lack of knowledge on the generality and transferability of results across species and regions. We present a multi-region, multi-species approach of modeling threshold responses, which we use to investigate whether threshold effects are similar across species and regions. We modeled local persistence and extinction dynamics of 25 forest-associated breeding birds based on detection/non-detection data, which were derived from repeated breeding bird atlases for the state of Vermont. We did not find threshold responses to be particularly well-supported, with 9 species supporting extinction thresholds and 5 supporting persistence thresholds. This contrasts with a previous study based on breeding bird atlas data from adjacent New York State, which showed that most species support persistence and extinction threshold models (15 and 22 of 25 study species respectively). In addition, species that supported a threshold model in both states had associated average threshold estimates of 61.41% (SE = 6.11, persistence) and 66.45% (SE = 9.15, extinction) in New York, compared to 51.08% (SE = 10.60, persistence) and 73.67% (SE = 5.70, extinction) in Vermont. Across species, thresholds were found at 19.45-87.96% forest cover for persistence and 50.82-91.02% for extinction dynamics. Through an approach that allows for broad-scale comparisons of threshold responses, we show that species vary in their threshold responses with regard to habitat amount, and that differences between even nearby regions can be pronounced. We present both ecological and methodological factors that may contribute to the different model results, but propose that regardless of the reasons behind these differences, our results merit a warning that

Observations and Simulations of Formation of Broad Plasma Depletions Through Merging Process

Science.gov (United States)

Huang, Chao-Song; Retterer, J. M.; Beaujardiere, O. De La; Roddy, P. A.; Hunton, D.E.; Ballenthin, J. O.; Pfaff, Robert F.

2012-01-01

Broad plasma depletions in the equatorial ionosphere near dawn are region in which the plasma density is reduced by 1-3 orders of magnitude over thousands of kilometers in longitude. This phenomenon is observed repeatedly by the Communication/Navigation Outage Forecasting System (C/NOFS) satellite during deep solar minimum. The plasma flow inside the depletion region can be strongly upward. The possible causal mechanism for the formation of broad plasma depletions is that the broad depletions result from merging of multiple equatorial plasma bubbles. The purpose of this study is to demonstrate the feasibility of the merging mechanism with new observations and simulations. We present C/NOFS observations for two cases. A series of plasma bubbles is first detected by C/NOFS over a longitudinal range of 3300-3800 km around midnight. Each of the individual bubbles has a typical width of approx 100 km in longitude, and the upward ion drift velocity inside the bubbles is 200-400 m/s. The plasma bubbles rotate with the Earth to the dawn sector and become broad plasma depletions. The observations clearly show the evolution from multiple plasma bubbles to broad depletions. Large upward plasma flow occurs inside the depletion region over 3800 km in longitude and exists for approx 5 h. We also present the numerical simulations of bubble merging with the physics-based low-latitude ionospheric model. It is found that two separate plasma bubbles join together and form a single, wider bubble. The simulations show that the merging process of plasma bubbles can indeed occur in incompressible ionospheric plasma. The simulation results support the merging mechanism for the formation of broad plasma depletions.

Singular surfaces in the open field line region of a diverted tokamak

International Nuclear Information System (INIS)

Reiman, A.

1995-05-01

The structure of the open field lines of a slightly nonaxisymmetric, poloidally diverted tokamak is explored by numerical integration of the field line equations for a simple model field. In practice, the nonaxisymmetry could be produced self-consistently by the nonlinear evolution of a free-boundary MHD mode, or it could be produced by field errors, or it could be imposed externally by design. In the presence of a nonaxisymmetric perturbation, the tokamak is shown to develop open field line regions of differing topology separated by singular surfaces. It is argued that the singular surfaces can be expected to play a role analogous to that of rational toroidal flux surfaces, in terms of constraining ideal MHD perturbations and thus constraining the free-energy that can be tapped by ideal MHD instabilities. The possibility of active control of free-boundary instabilities by means of currents driven on the open singular surfaces, which are directly accessible from the divertor plates, is discussed. Also discussed is the possibility of early detection of imminent disruptions through localized measurement of the singular surface currents

THE BROAD-LINED Type Ic SN 2012ap AND THE NATURE OF RELATIVISTIC SUPERNOVAE LACKING A GAMMA-RAY BURST DETECTION

Energy Technology Data Exchange (ETDEWEB)

Milisavljevic, D.; Margutti, R.; Parrent, J. T.; Soderberg, A. M.; Sanders, N. E.; Kamble, A.; Chakraborti, S.; Drout, M. R.; Kirshner, R. P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Fesen, R. A. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); Mazzali, P. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5RF (United Kingdom); Maeda, K. [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Silverman, J. M. [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Filippenko, A. V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Pickering, T. E. [Southern African Large Telescope, P.O. Box 9, Observatory 7935, Cape Town (South Africa); Kawabata, K. [Hiroshima Astrophysical Science Center, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Hattori, T. [Subaru Telescope, National Astronomical Observatory of Japan, Hilo, HI 96720 (United States); Hsiao, E. Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Stritzinger, M. D., E-mail: dmilisav@cfa.harvard.edu [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, DK-8000 Aarhus C (Denmark); and others

2015-01-20

We present ultraviolet, optical, and near-infrared observations of SN 2012ap, a broad-lined Type Ic supernova in the galaxy NGC 1729 that produced a relativistic and rapidly decelerating outflow without a gamma-ray burst signature. Photometry and spectroscopy follow the flux evolution from –13 to +272 days past the B-band maximum of –17.4 ± 0.5 mag. The spectra are dominated by Fe II, O I, and Ca II absorption lines at ejecta velocities of v ≈ 20,000 km s{sup –1} that change slowly over time. Other spectral absorption lines are consistent with contributions from photospheric He I, and hydrogen may also be present at higher velocities (v ≳ 27,000 km s{sup –1}). We use these observations to estimate explosion properties and derive a total ejecta mass of ∼2.7 M {sub ☉}, a kinetic energy of ∼1.0 × 10{sup 52} erg, and a {sup 56}Ni mass of 0.1-0.2 M {sub ☉}. Nebular spectra (t > 200 days) exhibit an asymmetric double-peaked [O I] λλ6300, 6364 emission profile that we associate with absorption in the supernova interior, although toroidal ejecta geometry is an alternative explanation. SN 2012ap joins SN 2009bb as another exceptional supernova that shows evidence for a central engine (e.g., black hole accretion or magnetar) capable of launching a non-negligible portion of ejecta to relativistic velocities without a coincident gamma-ray burst detection. Defining attributes of their progenitor systems may be related to notable observed properties including environmental metallicities of Z ≳ Z {sub ☉}, moderate to high levels of host galaxy extinction (E(B – V) > 0.4 mag), detection of high-velocity helium at early epochs, and a high relative flux ratio of [Ca II]/[O I] >1 at nebular epochs. These events support the notion that jet activity at various energy scales may be present in a wide range of supernovae.

The Broad-Lined Type Ic SN 2012ap and the Nature of Relativistic Supernovae Lacking a Gamma-Ray Burst Detection

Science.gov (United States)

Milisavljevic, D.; Margutti, R.; Parrent, J. T.; Soderberg, A. M.; Fesen, R. A.; Mazzali, P.; Maeda, K.; Sanders, N. E.; Cenko, S. B.; Silverman, J. M.

2014-01-01

We present ultraviolet, optical, and near-infrared observations of SN2012ap, a broad-lined Type Ic supernova in the galaxy NGC 1729 that produced a relativistic and rapidly decelerating outflow without a gamma-ray burst signature. Photometry and spectroscopy follow the flux evolution from -13 to +272 days past the B-band maximum of -17.4 +/- 0.5 mag. The spectra are dominated by Fe II, O I, and Ca II absorption lines at ejecta velocities of v approx. 20,000 km s(exp. -1) that change slowly over time. Other spectral absorption lines are consistent with contributions from photospheric He I, and hydrogen may also be present at higher velocities (v approx. greater than 27,000 km s(exp. -1)). We use these observations to estimate explosion properties and derive a total ejecta mass of 2.7 Solar mass, a kinetic energy of 1.0×1052 erg, and a (56)Ni mass of 0.1-0.2 Solar mass. Nebular spectra (t > 200 d) exhibit an asymmetric double-peaked [O I] lambda lambda 6300, 6364 emission profile that we associate with absorption in the supernova interior, although toroidal ejecta geometry is an alternative explanation. SN2012ap joins SN2009bb as another exceptional supernova that shows evidence for a central engine (e.g., black-hole accretion or magnetar) capable of launching a non-negligible portion of ejecta to relativistic velocities without a coincident gamma-ray burst detection. Defining attributes of their progenitor systems may be related to notable properties including above-average environmental metallicities of Z approx. greater than Solar Z, moderate to high levels of host-galaxy extinction (E(B -V ) > 0.4 mag), detection of high-velocity helium at early epochs, and a high relative flux ratio of [Ca II]/[O I] > 1 at nebular epochs. These events support the notion that jet activity at various energy scales may be present in a wide range of supernovae.

Extended emission-line regions in active galaxies

International Nuclear Information System (INIS)

Hutchings, J.B.; Hickson, P.

1988-01-01

Long-slit spectra of four active galaxies in the redshift range 0.06-0.10 are presented. Two have interacting companions. Spectra of the galaxies show extended narrow emission lines in all cases. Continuum color changes, emision-line ratio changes, and velocity changes with 1 arcsec resolution can be detected. Relative velocities between AGN and companion galaxies are also given. These objects appear to lie in galaxies in which there is considerable star-formation activity, and very extended line emision. 20 references

Beam, multi-beam and broad beam production with COMIC devices

International Nuclear Information System (INIS)

Sortais, P.; Lamy, T.; Medard, J.; Angot, J.; Peaucelle, C.

2012-01-01

The COMIC discharge cavity is a very versatile technology. We will present new results and devices that match new applications like: molecular beams, ultra compact beam line for detectors calibrations, quartz source for on-line application, high voltage platform source, sputtering /assistance broad beams and finally, a quite new use, high energy multi-beam production for surface material modifications. In more details, we will show that the tiny discharge of COMIC can mainly produce molecular ions (H 3+ ). We will present the preliminary operation of the fully quartz ISOLDE COMIC version, in collaboration with IPN Lyon, we will present a first approach for a slit extraction version of a three cavity device, and after discussing about various extraction systems on the multi discharge device (41 cavities) we will show the low energy broad beam (2 KV) and high energy multi-beams (10 beams up to 30 KV) productions. We will specially present the different extraction systems adapted to each application and the beams characteristics which are strongly dependent on the voltage distribution of an accel-accel two electrodes extraction system. The paper is followed by the slides of the presentation. (authors)

THE STRUCTURE OF THE SEED YIELD OF BROAD BEANS IN THE SOUTH CENTRAL ZONE OF THE SOUTH OF THE CENTRAL BLACK EARTH REGION

Directory of Open Access Journals (Sweden)

Yu. N. Kurkina

2018-01-01

Full Text Available Rich in high quality protein, vitamins, carbohydrates, organic acids and trace elements seeds, green fruits and young leaves broad beans (Vicia faba L. var. major Harz has long been used in the food, and the culture of beans are promising in biological agriculture and horticulture. The aim of this work was to study the structure of seed production of different varieties of broad beans in the South Central zone of the region. At the Botanical garden BelSU (Belgorod to study the structure of seed production of different varieties of broad beans (Belarusiskie, Velena, Russkie chernie, Aquadul and determined the biochemical composition of seeds. Optimal height of attachment of the first fruit for mechanical harvesting (20-25 cm characteristic of plants of all studied varieties. Weight of the fetus, according to the coefficient of variability, equal to 45%, distinguished by a strong variability on grades with a maximum grade of Velena. The length of fruit ranged from 9 to 13 cm and were characterized by moderate variability (V=20%. Seeds production is determinened not only by size of fruits of beans, but and its important components such as 1000 seed weight. Protein content in the seeds at 30% different varieties of broad beans domestic breeding. Contents of nitrogen, potassium, phosphorus and iron is higher in the cotyledons than in the skin. Dark purple color of the seed varieties of Russian black is due to the biosynthesis useful for human organism anthocyanins in seed peel.

BROAD BALMER WINGS IN BA HYPER/SUPERGIANTS DISTORTED BY DIFFUSE INTERSTELLAR BANDS: FIVE EXAMPLES IN THE 30 DORADUS REGION FROM THE VLT-FLAMES TARANTULA SURVEY

Energy Technology Data Exchange (ETDEWEB)

Walborn, Nolan R.; Sana, Hugues; Sabbi, Elena, E-mail: walborn@stsci.edu, E-mail: hsana@stsci.edu, E-mail: sabbi@stsci.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); and others

2015-08-10

Extremely broad emission wings at Hβ and Hα have been found in VLT-FLAMES Tarantula Survey data for five very luminous BA supergiants in or near 30 Doradus in the Large Magellanic Cloud. The profiles of both lines are extremely asymmetrical, which we have found to be caused by very broad diffuse interstellar bands (DIBs) in the longward wing of Hβ and the shortward wing of Hα. These DIBs are well known to interstellar but not to many stellar specialists, so that the asymmetries may be mistaken for intrinsic features. The broad emission wings are generally ascribed to electron scattering, although we note difficulties for that interpretation in some objects. Such profiles are known in some Galactic hyper/supergiants and are also seen in both active and quiescent Luminous Blue Variables (LBVs). No prior or current LBV activity is known in these 30 Dor stars, although a generic relationship to LBVs is not excluded; subject to further observational and theoretical investigation, it is possible that these very luminous supergiants are approaching the LBV stage for the first time. Their locations in the HRD and presumed evolutionary tracks are consistent with that possibility. The available evidence for spectroscopic variations of these objects is reviewed, while recent photometric monitoring does not reveal variability. A search for circumstellar nebulae has been conducted, with an indeterminate result for one of them.

Contribution of the Electron Scattering Process to the Broad Hα Wings

Directory of Open Access Journals (Sweden)

Sekeráš M.

2012-06-01

Full Text Available We modeled the extended wings of the OVI 1032, 1038 Å resonance lines and He II 1640 Å emission line in the spectra of Z And, AG Dra and V1016 Cyg by the electron scattering process. By this way we determined the electron temperature and the electron optical depth of the layer of electrons, through which the line photons are transferred in the direction of the observer. We derived an empirical relationship between the emission measure of the symbiotic nebula and the electron optical depth. This relationship allows us to distinguish the flux contribution in the broad Hα wings, which is due to the electron scattering and that produced by the Hα transition in the moving hydrogen plasma. For example, subtracting the electron scattering contribution from the Hα line profile leads to a reduction in the mass-loss rate by approximately 15 %.

Near infrared photometry of violent star formation regions

International Nuclear Information System (INIS)

Melnick, J.; Terlevich, R.; Moles, M.

1985-01-01

Near infrared broad band photometry and CO indices for a significant number of Violent Star Formation Regions are presented. The existence of a narrow correlation between W (Hβ) and IR colour is confirmed. The interpretation of this relation as an age sequence implies a correlation between CO index and W(Hβ) which is not found. It is argued however that this failure is most likely a consequence of using narrow band filters to determine CO indices in objects with strong emission-line spectra. (author)

A TEST OF THE NATURE OF THE FE K LINE IN THE NEUTRON STAR LOW-MASS X-RAY BINARY SERPENS X-1

Energy Technology Data Exchange (ETDEWEB)

Chiang, Chia-Ying; Cackett, Edward M. [Department of Physics and Astronomy, Wayne State University, 666 W. Hancock, Detroit, MI 48202 (United States); Miller, Jon M. [Department of Astronomy, The University of Michigan, 500 Church Street, Ann Arbor, MI48109-1046 (United States); Barret, Didier [Universite de Toulouse, UPS-OMP, Toulouse (France); Fabian, Andy C.; Parker, Michael L. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); D’Aì, Antonino [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Bhattacharyya, Sudip [Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, Mumbai 400005 (India); Burderi, Luciano [Dipartimento di Fisica, Università degli Studi di Cagliari, SP Monserrato-Sestu, KM 0.7, I-09042 Monserrato (Italy); Salvo, Tiziana Di; Iaria, Rosario [Dipartimento di Fisica e Chimica, Universitá di Palermo, via Archirafi 36, I-90123 Palermo (Italy); Egron, Elise [INAF-Osservatorio Astronomico di Cagliari, via della Scienza 5, I-09047 Selargius (Italy); Homan, Jeroen [MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue 37-582D, Cambridge, MA 02139 (United States); Lin, Dacheng [Space Science Center, University of New Hampshire, Durham, NH 03824 (United States); Miller, M. Coleman, E-mail: ft8320@wayne.edu [Department of Astronomy and Joint Space-Science Institute, University of Maryland, College Park, MD 20742-2421 (United States)

2016-04-20

Broad Fe K emission lines have been widely observed in the X-ray spectra of black hole systems as well as in neutron star systems. The intrinsically narrow Fe K fluorescent line is generally believed to be part of the reflection spectrum originating in an illuminated accretion disk which is broadened by strong relativistic effects. However, the nature of the lines in neutron star low-mass X-ray binaries (LMXBs) has been a matter of debate. We therefore obtained the longest, high-resolution X-ray spectrum of a neutron star LMXB to date with a 300 ks Chandra High Energy Transmission Grating Spectrometer (HETGS) observation of Serpens X-1. The observation was taken under the “continuous clocking” mode, and thus was free of photon pile-up effects. We carry out a systematic analysis and find that the blurred reflection model fits the Fe line of Serpens X-1 significantly better than a broad Gaussian component does, implying that the relativistic reflection scenario is much preferred. Chandra HETGS also provides a highest spectral resolution view of the Fe K region and we find no strong evidence for additional narrow lines.

Socioeconomic evaluation of broad-scale land management strategies.

Science.gov (United States)

Lisa K. Crone; Richard W. Haynes

2001-01-01

This paper examines the socioeconomic effects of alternative management strategies for Forest Service and Bureau of Land Management lands in the interior Columbia basin. From a broad-scale perspective, there is little impact or variation between alternatives in terms of changes in total economic activity or social conditions in the region. However, adopting a finer...

RNA expression in a cartilaginous fish cell line reveals ancient 3′ noncoding regions highly conserved in vertebrates

Science.gov (United States)

Forest, David; Nishikawa, Ryuhei; Kobayashi, Hiroshi; Parton, Angela; Bayne, Christopher J.; Barnes, David W.

2007-01-01

We have established a cartilaginous fish cell line [Squalus acanthias embryo cell line (SAE)], a mesenchymal stem cell line derived from the embryo of an elasmobranch, the spiny dogfish shark S. acanthias. Elasmobranchs (sharks and rays) first appeared >400 million years ago, and existing species provide useful models for comparative vertebrate cell biology, physiology, and genomics. Comparative vertebrate genomics among evolutionarily distant organisms can provide sequence conservation information that facilitates identification of critical coding and noncoding regions. Although these genomic analyses are informative, experimental verification of functions of genomic sequences depends heavily on cell culture approaches. Using ESTs defining mRNAs derived from the SAE cell line, we identified lengthy and highly conserved gene-specific nucleotide sequences in the noncoding 3′ UTRs of eight genes involved in the regulation of cell growth and proliferation. Conserved noncoding 3′ mRNA regions detected by using the shark nucleotide sequences as a starting point were found in a range of other vertebrate orders, including bony fish, birds, amphibians, and mammals. Nucleotide identity of shark and human in these regions was remarkably well conserved. Our results indicate that highly conserved gene sequences dating from the appearance of jawed vertebrates and representing potential cis-regulatory elements can be identified through the use of cartilaginous fish as a baseline. Because the expression of genes in the SAE cell line was prerequisite for their identification, this cartilaginous fish culture system also provides a physiologically valid tool to test functional hypotheses on the role of these ancient conserved sequences in comparative cell biology. PMID:17227856

Temperature and emission-line structure at the edges of H II regions

International Nuclear Information System (INIS)

Mallik, D.C.V.

1975-01-01

Models of ionization fronts located at the edges of expanding H ii regions are presented. These fronts are of the weak D-type and are preceded by shocks in the H i clouds. Since the energy input time is smaller than the cooling time, the gas is found to heat up to a high temperature immediately following ionization. At the trailing edge of the front, the temperature decreases and the ionized gas merges with the main bulk of the nebula where the physical processes are in equilibrium. The emission in O ii and N ii lines is greatly enhanced because of the high temperature at the front. The emission in these and other important lines is calculated and compared with Hβ. Effects of different velocities of flow, of different exciting stars, and of different gas densities on the structure of the fronts are also investigated

Specific degradation of 3' regions of GUS mRNA in posttranscriptionally silenced tobacco lines may be related to 5'-3' spreading of silencing

DEFF Research Database (Denmark)

Braunstein, Thomas Hartig; Moury, Benoit; Johannessen, Marina

2002-01-01

background, we have performed detailed analyses of target regions in three spontaneously beta-glucuronidase (GUS) silencing tobacco lines of different origin. From quantitative cosuppression experiments, we show that the main target region in all three tobacco lines is found within the 3' half of the GUS...... VIGS. Surprisingly, only evidence for spreading of the target region in the 5'-3' direction was obtained. This finding may help explain why the majority of target regions examined to date lie within the 3' region of transgenes....

PHYSICAL CONDITIONS IN THE INNER NARROW-LINE REGION OF THE SEYFERT 2 GALAXY MARKARIAN 573

International Nuclear Information System (INIS)

Kraemer, S. B.; Trippe, M. L.; Crenshaw, D. M.; Fischer, T. C.; Melendez, M.; Schmitt, H. R.

2009-01-01

We have examined the physical conditions within a bright emission-line knot in the inner narrow-line region (NLR) of the Seyfert 2 galaxy Mrk 573 using optical spectra and photoionization models. The spectra were obtained with the Hubble Space Telescope/Space Telescope Imaging Spectrograph, through the 0.''2 x 52.''0 slit, at a position angle of -71. 0 2, with the G430L and G750M gratings. Comparing the spatial emission-line profiles, we found [Fe X] λ 6734 barely resolved, [O III] λ5007 centrally peaked, but broader than [Fe X], and [O II] λ3727 the most extended. Spectra of the central knot were extracted from a region 1.''1 in extent, corresponding to the full width at zero intensity in the cross-dispersion direction, of the knot. The spectra reveal that [Fe X] is broader in velocity width and blueshifted compared with lines from less ionized species. Our estimate of the bolometric luminosity indicates that the active galactic nucleus (AGN) is radiating at or above its Eddington luminosity, which is consistent with its identification as a hidden Narrow-Line Seyfert 1. We were able to successfully match the observed emission-line ratios with a three-component photoionization model. Two components, one to account for the [O III] emission and another in which the [Fe X] arises, are directly ionized by the AGN, while [O II] forms in a third component, which is ionized by a heavily absorbed continuum. Based on our assumed ionizing continuum and the model parameters, we determined that the two directly ionized components are ∼55 pc from the AGN. We have found similar radial distances for the central knots in the Seyfert 2 galaxies Mrk 3 and NGC 1068, but much smaller radial distances for the inner NLR in the Seyfert 1 galaxies NGC 4151 and NGC 5548. Although in general agreement with the unified model, these results suggest that the obscuring material in Seyfert galaxies extends out to at least tens of parsecs from the AGN.

Classification spectra of Sanduleak and Stephenson emission-line stars

International Nuclear Information System (INIS)

Allen, D.A.

1978-01-01

Low dispersion slit spectra of 89 emission-line stars are described; these stars were originally located and classified by Sanduleak and Stephenson in an objective-prism survey. The new data broadly confirm the classification scheme adopted by Sanduleak and Stephenson. In particular most of the large number of symbiotic stars they classified have been confirmed and others found. Many of these contain strong, broad emission bands in their red spectra. Two new Wolf-Rayet stars, one new planetary nebula and two new bipolar reflection nebulae involving hidden emission-line stars have been found. (author)

Classification spectra of Sanduleak and Stephenson emission-line stars

Energy Technology Data Exchange (ETDEWEB)

Allen, D A [Anglo-Australian Observatory, Epping (Australia)

1978-09-01

Low dispersion slit spectra of 89 emission-line stars are described; these stars were originally located and classified by Sanduleak and Stephenson in an objective-prism survey. The new data broadly confirm the classification scheme adopted by Sanduleak and Stephenson. In particular most of the large number of symbiotic stars they classified have been confirmed and others found. Many of these contain strong, broad emission bands in their red spectra. Two new Wolf-Rayet stars, one new planetary nebula and two new bipolar reflection nebulae involving hidden emission-line stars have been found.

Numerical simulation of mesoscale surface pressure features with trailing stratiform squall lines using WRF -ARW model over Gangetic West Bengal region

Science.gov (United States)

Dawn, Soma; Satyanarayana, A. N. V.

2018-01-01

In the present study, an attempt has been made to investigate the simulation of mesoscale surface pressure patterns like pre-squall mesolow, mesohigh and wake low associated with leading convective line-trailing stratiform (TS) squall lines over Gangetic West Bengal (GWB). For this purpose, a two way interactive triple nested domain with high resolution WRF model having2 km grid length in the innermost domain is used. The model simulated results are compared with the available in-situ observations obtained as a part of Severe Thunderstorm: Observations and Regional Modeling (STORM) programme, reflectivity products of Doppler Weather Radar (DWR) Kolkata and TRMM rainfall. Three TS squall lines (15 May 2009, 5 May 2010 and 7 May 2010) are chosen during pre-monsoon thunderstorm season for this study. The model simulated results of diurnal variation of temperature, relative humidity, wind speed and direction at the station Kharagpur in GWB region reveal a sudden fall in temperature, increase in the amount of relative humidity and sudden rise in wind speed during the arrival of the storms. Such results are well comparable with the observations though there are some leading or lagging of time in respect of actual occurrences of such events. The study indicates that the model is able to predict the occurrences of three typical surface pressure features namely: pre-squall mesolow, meso high and wake low. The predicted surface parameters like accumulated rainfall, maximum reflectivity and vertical profiles (temperature, relative humidity and winds) are well accorded with the observations. The convective and stratiform precipitation region of the TS squall lines are well represented by the model. A strong downdraft is observed to be a contributory factor for formation of mesohigh in the convective region of the squall line. Wake low is observed to reside in the stratiform rain region and the descending dry air at this place has triggered the wake low through adiabatic

Runs 800, 813, 842 and physics runs from 18.1.77 to 21.5.77, Development of a new set-up for working line measurements including a Fast Fourier Transform Spectrum Analyser and using weak beam excitiation with broad-band noise

CERN Document Server

Borer, J

1977-01-01

Runs 800, 813, 842 and physics runs from 18.1.77 to 21.5.77, Development of a new set-up for working line measurements including a Fast Fourier Transform Spectrum Analyser and using weak beam excitiation with broad-band noise

SIMULTANEOUS ULTRAVIOLET AND OPTICAL EMISSION-LINE PROFILES OF QUASARS: IMPLICATIONS FOR BLACK HOLE MASS DETERMINATION

International Nuclear Information System (INIS)

Ho, Luis C.; Dong Xiaobo; Goldoni, Paolo; Ponti, Gabriele; Greene, Jenny E.

2012-01-01

The X-shooter instrument on the Very Large Telescope was used to obtain spectra of seven moderate-redshift quasars simultaneously covering the spectral range ∼3000 Å to 2.5 μm. At z ≈ 1.5, most of the prominent broad emission lines in the ultraviolet to optical region are captured in their rest frame. We use this unique data set, which mitigates complications from source variability, to intercompare the line profiles of C IV λ1549, C III] λ1909, Mg II λ2800, and Hα and evaluate their implications for black hole (BH) mass estimation. We confirm that Mg II and the Balmer lines share similar kinematics and that they deliver mutually consistent BH mass estimates with minimal internal scatter (∼<0.1 dex) using the latest virial mass estimators. Although no virial mass formalism has yet been calibrated for C III], this line does not appear promising for such an application because of the large spread of its velocity width compared to lines of both higher and lower ionization; part of the discrepancy may be due to the difficulty of deblending C III] from its neighboring lines. The situation for C IV is complex and, because of the limited statistics of our small sample, inconclusive. On the one hand, slightly more than half of our sample (4/7) have C IV line widths that correlate reasonably well with Hα line widths, and their respective BH mass estimates agree to within ∼0.15 dex. The rest, on the other hand, exhibit exceptionally broad C IV profiles that overestimate virial masses by factors of 2-5 compared to Hα. As C IV is widely used to study BH demographics at high redshifts, we urgently need to revisit our analysis with a larger sample.

Photoionization Models of the H_2 Emission of the Narrow Line Region of AGNs

Science.gov (United States)

Aleman, I.; Gruenwald, R.

2011-05-01

The excitation mechanism of the narrow line region (NLR) of AGNs is still an open question. Excitation by UV radiation from O and B stars, x-rays from the central black hole, shock from supernovae or jets, or a combination of these mechanisms have been suggested. In the present work, we use photoionization models to study the excitation mechanisms of the H_2 infrared emission lines in the NLR. In the literature, analyzes of the H_2 emission have been done assuming that the molecules is present only in neutral regions (photodissociation regions, x-ray-dominated regions, or shocks; Veilleux et al. 1997, Krabbe et al. 2000, Rigopoulou et al. 2002, Rodriguez-Ardila et al. 2004, 2005, and Davies et al. 2005). However, they are not conclusive. In previous work (Aleman & Gruenwald 2004, 2011), we show that the H_2 emission from the ionized region of PNe can be significant for planetary nebulae (PNe) with hot central stars (T⋆ > 150000 K). Such stars produce copious amounts of high energy photons, which create an extended partially ionized region that favors the H_2 survival. The conditions in the NLR are similar to those in PNe with hot central stars, so we can expect that the H_2 emission might also be important. We obtain and analyze a grid of photoionization models for different NRL parameters. We study the resulting H_2 density and emission, as well as, the formation, destruction, excitation, and de-excitation mechanisms. The higher values observed for the H_2 1-0 S(1)/Brγ ratio cannot be reproduced by our models. The calculated ratios are between 10^-8 and 10^-1, while the observational ration can be as high as 10. The calculated ratio is strongly anti-correlated with the ionization parameter (U) and only models with U<10-3 result in ratios inside the observational range. We show that the NLR is an environment more hostile to the H_2 molecule than the ionized region of PNe. Another interesting result of our calculations is that the H_2 formation on grain surfaces

A CHANDRA SURVEY OF THE X-RAY PROPERTIES OF BROAD ABSORPTION LINE RADIO-LOUD QUASARS

International Nuclear Information System (INIS)

Miller, B. P.; Brandt, W. N.; Garmire, G. P.; Gibson, R. R.; Shemmer, O.

2009-01-01

This work presents the results of a Chandra study of 21 broad absorption line (BAL) radio-loud quasars (RLQs). We conducted a Chandra snapshot survey of 12 bright BAL RLQs selected from Sloan Digital Sky Survey Data/Faint Images of the Radio Sky data and possessing a wide range of radio and C IV absorption properties. Optical spectra were obtained nearly contemporaneously with the Hobby-Eberly Telescope; no strong flux or BAL variability was seen between epochs. In addition to the snapshot targets, we include in our sample nine additional BAL RLQs possessing archival Chandra coverage. We compare the properties of (predominantly high-ionization) BAL RLQs to those of non-BAL RLQs as well as to BAL radio-quiet quasars (RQQs) and non-BAL RQQs for context. All 12 snapshots and 8/9 archival BAL RLQs are detected, with observed X-ray luminosities less than those of non-BAL RLQs having comparable optical/UV luminosities by typical factors of 4.1-8.5. (BAL RLQs are also X-ray weak by typical factors of 2.0-4.5 relative to non-BAL RLQs having both comparable optical/UV and radio luminosities.) However, BAL RLQs are not as X-ray weak relative to non-BAL RLQs as are BAL RQQs relative to non-BAL RQQs. While some BAL RLQs have harder X-ray spectra than typical non-BAL RLQs, some have hardness ratios consistent with those of non-BAL RLQs, and there does not appear to be a correlation between X-ray weakness and spectral hardness, in contrast to the situation for BAL RQQs. RLQs are expected to have X-ray continuum contributions from both accretion-disk corona and small-scale jet emission. While the entire X-ray continuum in BAL RLQs cannot be obscured to the same degree as in BAL RQQs, we calculate that the jet is likely partially covered in many BAL RLQs. We comment briefly on implications for geometries and source ages in BAL RLQs.

Weak hard X-ray emission from broad absorption line quasars: evidence for intrinsic X-ray weakness

International Nuclear Information System (INIS)

Luo, B.; Brandt, W. N.; Scott, A. E.; Alexander, D. M.; Gandhi, P.; Stern, D.; Teng, S. H.; Arévalo, P.; Bauer, F. E.; Boggs, S. E.; Craig, W. W.; Christensen, F. E.; Comastri, A.; Farrah, D.; Hailey, C. J.; Harrison, F. A.; Koss, M.; Ogle, P.; Puccetti, S.; Saez, C.

2014-01-01

We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z < 1.3. However, their rest-frame ≈2 keV luminosities are 14 to >330 times weaker than expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with ≲ 45 counts in the 3-24 keV band, and the other three are not detected. The hard X-ray (8-24 keV) weakness observed by NuSTAR requires Compton-thick absorption if these objects have nominal underlying X-ray emission. However, a soft stacked effective photon index (Γ eff ≈ 1.8) for this sample disfavors Compton-thick absorption in general. The uniform hard X-ray weakness observed by NuSTAR for this and the pilot samples selected with <10 keV weakness also suggests that the X-ray weakness is intrinsic in at least some of the targets. We conclude that the NuSTAR observations have likely discovered a significant population (≳ 33%) of intrinsically X-ray weak objects among the BAL quasars with significantly weak <10 keV emission. We suggest that intrinsically X-ray weak quasars might be preferentially observed as BAL quasars.

PROBING THE PHYSICS OF NARROW LINE REGIONS IN ACTIVE GALAXIES. II. THE SIDING SPRING SOUTHERN SEYFERT SPECTROSCOPIC SNAPSHOT SURVEY (S7)

Energy Technology Data Exchange (ETDEWEB)

Dopita, Michael A.; Davies, Rebecca; Kewley, Lisa; Hampton, Elise; Sutherland, Ralph [RSAA, Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia); Shastri, Prajval; Kharb, Preeti; Jose, Jessy; Bhatt, Harish; Ramya, S. [Indian Institute of Astrophysics, Koramangala 2 B Block, Bangalore 560034 (India); Scharwächter, Julia [LERMA, Observatoire de Paris, CNRS, UMR 8112, 61 Avenue de l’Observatoire, F-75014 Paris (France); Jin, Chichuan [Qian Xuesen Laboratory for Space Technology, Beijing (China); Banfield, Julie [CSIRO Astronomy and Space Science, P.O. Box 76, Epping NSW, 1710 Australia (Australia); Zaw, Ingyin [New York University (Abu Dhabi), 70 Washington Square South, New York, NY 10012 (United States); Juneau, Stéphanie [CEA-Saclay, DSM/IRFU/SAp, F-91191 Gif-sur-Yvette (France); James, Bethan [Institute of Astronomy, Cambridge University, Madingley Road, Cambridge CB3 0HA (United Kingdom); Srivastava, Shweta, E-mail: Michael.Dopita@anu.edu.au [Astronomy and Astrophysics Division, Physical Research Laboratory, Ahmedabad 380009 (India)

2015-03-15

Here we describe the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) and present results on 64 galaxies drawn from the first data release. The S7 uses the Wide Field Spectrograph mounted on the ANU 2.3 m telescope located at the Siding Spring Observatory to deliver an integral field of 38 × 25 arcsec at a spectral resolution of R = 7000 in the red (530–710 nm), and R = 3000 in the blue (340–560 nm). From these data cubes we have extracted the narrow-line region spectra from a 4 arcsec aperture centered on the nucleus. We also determine the Hβ and [O iii] λ5007 fluxes in the narrow lines, the nuclear reddening, the reddening-corrected relative intensities of the observed emission lines, and the Hβ and [O iii] λ5007 luminosities determined from spectra for which the stellar continuum has been removed. We present a set of images of the galaxies in [O iii] λ5007, [N ii] λ6584, and Hα, which serve to delineate the spatial extent of the extended narrow-line region and also to reveal the structure and morphology of the surrounding H ii regions. Finally, we provide a preliminary discussion of those Seyfert 1 and Seyfert 2 galaxies that display coronal emission lines in order to explore the origin of these lines.

NEW STRONG-LINE ABUNDANCE DIAGNOSTICS FOR H II REGIONS: EFFECTS OF κ-DISTRIBUTED ELECTRON ENERGIES AND NEW ATOMIC DATA

Energy Technology Data Exchange (ETDEWEB)

Dopita, Michael A.; Sutherland, Ralph S.; Nicholls, David C.; Kewley, Lisa J.; Vogt, Frédéric P. A., E-mail: Michael.Dopita@anu.edu.au [Research School of Astronomy and Astrophysics, Australian National University, Cotter Rd., Weston ACT 2611 (Australia)

2013-09-01

Recently, Nicholls et al., inspired by in situ observations of solar system astrophysical plasmas, suggested that the electrons in H II regions are characterized by a κ-distribution of energies rather than a simple Maxwell-Boltzmann distribution. Here, we have collected together new atomic data within a modified photoionization code to explore the effects of both the new atomic data and the κ-distribution on the strong-line techniques used to determine chemical abundances in H II regions. By comparing the recombination temperatures (T {sub rec}) with the forbidden line temperatures (T {sub FL}), we conclude that κ ∼ 20. While representing only a mild deviation from equilibrium, this result is sufficient to strongly influence abundances determined using methods that depend on measurements of the electron temperature from forbidden lines. We present a number of new emission line ratio diagnostics that cleanly separate the two parameters determining the optical spectrum of H II regions—the ionization parameter q or U and the chemical abundance, 12+log(O/H). An automated code to extract these parameters is presented. Using the homogeneous data set from van Zee et al., we find self-consistent results between all of these different diagnostics. The systematic errors between different line ratio diagnostics are much smaller than those found in the earlier strong-line work. Overall, the effect of the κ-distribution on the strong-line abundances derived solely on the basis of theoretical models is rather small.

Stress Analysis of Boom of Special Mobile Crane for Plain Region in Transmission Line

Science.gov (United States)

Qin, Jian; Shao, Tao; Chen, Jun; Wan, Jiancheng; Li, Zhonghuan; Jiang, Ming

2017-10-01

Basis of the boom force analysis of special mobile crane for plain region in transmission line, the load type of boom design is confirmed. According to the different combinations of boom sections, the composite pattern of the different boom length is obtained to suit the actual conditions of boom overlapping. The large deformation model is employed with FEM to simulate the stress distribution of boom, and the calculation results are checked. The performance curves of rated load with different arm length and different working range are obtained, which ensures the lifting capacity of special mobile crane meeting the requirement of tower erection of transmission line. The proposed FEM of boom of mobile crane would provide certain guiding and reference to the boom design.

An X-ray variable absorber within the broad line region in Fairall 51

Czech Academy of Sciences Publication Activity Database

Svoboda, Jiří; Beuchert, T.; Guainazzi, M.; Longinotti, A. L.; Piconcelli, E.; Wilms, J.

2015-01-01

Roč. 578, June (2015), A96/1-A96/11 ISSN 0004-6361 R&D Projects: GA ČR(CZ) GP14-20970P Institutional support: RVO:67985815 Keywords : active galactic nuclei * supermassive black - holes * warped accretion discs Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.378, year: 2014

Imaging spectrophotometry of ionized gas in NGC 1068. I - Kinematics of the narrow-line region

Science.gov (United States)

Cecil, Gerald; Bland, Jonathan; Tully, R. Brent

1990-01-01

The kinematics of collisionally excited forbidden N II 6548, 6583 across the inner 1 arcmin diameter of the nearby Seyfert galaxy NGC 1068 is mapped using an imaging Fabry-Perot interferometer and low-noise CCD. The stack of monochromatic images, which spatially resolved the high-velocity gas, was analyzed for kinematic and photometric content. Profiles agree well with previous long-slit work, and their complete spatial coverage makes it possible to constrain the gas volume distribution. It is found that the narrow-line region is distributed in a thick center-darkened, line-emitting cylinder that envelopes the collimated radio jet. Three distinct kinematic subsystems, of which the cylinder is composed, are discussed in detail. Detailed behavior of the emission-line profiles, at the few points in the NE quadrant with simple kinematics, argues that the ionized gas develops a significant component of motion perpendicular to the jet axis.

A Deep Chandra ACIS Study of NGC 4151. II. The Innermost Emission Line Region and Strong Evidence for Radio Jet-NLR Cloud Collision

Science.gov (United States)

Wang, Junfeng; Fabbiano, Giuseppina; Elvis, Martin; Risaliti, Guido; Mundell, Carole G.; Karovska, Margarita; Zezas, Andreas

2011-07-01

We have studied the X-ray emission within the inner ~150 pc radius of NGC 4151 by constructing high spatial resolution emission line images of blended O VII, O VIII, and Ne IX. These maps show extended structures that are spatially correlated with the radio outflow and optical [O III] emission. We find strong evidence for jet-gas cloud interaction, including morphological correspondences with regions of X-ray enhancement, peaks of near-infrared [Fe II] emission, and optical clouds. In these regions, moreover, we find evidence of elevated Ne IX/O VII ratios; the X-ray emission of these regions also exceeds that expected from nuclear photoionization. Spectral fitting reveals the presence of a collisionally ionized component. The thermal energy of the hot gas suggests that >~ 0.1% of the estimated jet power is deposited into the host interstellar medium through interaction between the radio jet and the dense medium of the circumnuclear region. We find possible pressure equilibrium between the collisionally ionized hot gas and the photoionized line-emitting cool clouds. We also obtain constraints on the extended iron and silicon fluorescent emission. Both lines are spatially unresolved. The upper limit on the contribution of an extended emission region to the Fe Kα emission is <~ 5% of the total, in disagreement with a previous claim that 65% of the Fe Kα emission originates in the extended narrow line region.

SPECTRAL OPTICAL MONITORING OF THE NARROW-LINE SEYFERT 1 GALAXY Ark 564

International Nuclear Information System (INIS)

Shapovalova, A. I.; Burenkov, A. N.; Popović, L. Č.; Kovačević, J.; Chavushyan, V. H.; Valdes, J. R.; Torrealba, J.; Carrasco, L.; Ilić, D.; Kovačević, A.; Kollatschny, W.; Bochkarev, N. G.; León-Tavares, J.; Mercado, A.; Benítez, E.; Dultzin, D.; De la Fuente, E.

2012-01-01

We present the results of a long-term (1999-2010) spectral optical monitoring campaign of the active galactic nucleus (AGN) Ark 564, which shows a strong Fe II line emission in the optical. This AGN is a narrow-line Seyfert 1 (NLS1) galaxy, a group of AGNs with specific spectral characteristics. We analyze the light curves of the permitted Hα, Hβ, optical Fe II line fluxes, and the continuum flux in order to search for a time lag between them. Additionally, in order to estimate the contribution of iron lines from different multiplets, we fit the Hβ and Fe II lines with a sum of Gaussian components. We find that during the monitoring period the spectral variation (F max /F min ) of Ark 564 is between 1.5 for Hα and 1.8 for the Fe II lines. The correlation between the Fe II and Hβ flux variations is of higher significance than that of Hα and Hβ (whose correlation is almost absent). The permitted-line profiles are Lorentzian-like and do not change shape during the monitoring period. We investigate, in detail, the optical Fe II emission and find different degrees of correlation between the Fe II emission arising from different spectral multiplets and the continuum flux. The relatively weak and different degrees of correlations between permitted lines and continuum fluxes indicate a rather complex source of ionization of the broad-line emission region.

SPECTRAL OPTICAL MONITORING OF THE NARROW-LINE SEYFERT 1 GALAXY Ark 564

Energy Technology Data Exchange (ETDEWEB)

Shapovalova, A. I.; Burenkov, A. N. [Special Astrophysical Observatory of the Russian AS, Nizhnij Arkhyz, Karachaevo-Cherkesia 369167 (Russian Federation); Popovic, L. C.; Kovacevic, J. [Astronomical Observatory, Volgina 7, 11160 Belgrade 74 (Serbia); Chavushyan, V. H.; Valdes, J. R.; Torrealba, J.; Carrasco, L. [Instituto Nacional de Astrofisica, Optica y Electronica, Apartado Postal 51-216, 72000 Puebla (Mexico); Ilic, D.; Kovacevic, A. [Isaac Newton Institute of Chile, Yugoslavia Branch, Belgrade (Serbia); Kollatschny, W. [Institut fuer Astrophysik, Georg-August-Universitaet, Goettingen (Germany); Bochkarev, N. G. [Sternberg Astronomical Institute, Moscow (Russian Federation); Leon-Tavares, J. [Aalto University Metsaehovi Radio Observatory, Metsaehovintie 114, FIN-02540 Kylmaelae (Finland); Mercado, A. [Universidad Politecnica de Baja California, Av. de la Industria 291, 21010 Mexicali, B.C. (Mexico); Benitez, E.; Dultzin, D. [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-264, Mexico, D.F. 04510 (Mexico); De la Fuente, E., E-mail: ashap@sao.ru [Instituto de Astronomia y Meteorologia, Dpto. de Fisica CUCEI, Universidad de Guadalajara, Av. Vallarta 2602, 44130 Guadalajara, Jalisco (Mexico)

2012-09-15

We present the results of a long-term (1999-2010) spectral optical monitoring campaign of the active galactic nucleus (AGN) Ark 564, which shows a strong Fe II line emission in the optical. This AGN is a narrow-line Seyfert 1 (NLS1) galaxy, a group of AGNs with specific spectral characteristics. We analyze the light curves of the permitted H{alpha}, H{beta}, optical Fe II line fluxes, and the continuum flux in order to search for a time lag between them. Additionally, in order to estimate the contribution of iron lines from different multiplets, we fit the H{beta} and Fe II lines with a sum of Gaussian components. We find that during the monitoring period the spectral variation (F{sub max}/F{sub min}) of Ark 564 is between 1.5 for H{alpha} and 1.8 for the Fe II lines. The correlation between the Fe II and H{beta} flux variations is of higher significance than that of H{alpha} and H{beta} (whose correlation is almost absent). The permitted-line profiles are Lorentzian-like and do not change shape during the monitoring period. We investigate, in detail, the optical Fe II emission and find different degrees of correlation between the Fe II emission arising from different spectral multiplets and the continuum flux. The relatively weak and different degrees of correlations between permitted lines and continuum fluxes indicate a rather complex source of ionization of the broad-line emission region.

The Size-Luminosity Relationship of Quasar Narrow-Line Regions

Science.gov (United States)

Dempsey, Ross; Zakamska, Nadia L.

2018-04-01

The presence of an active galactic nucleus (AGN) can strongly affect its host. Due to the copious radiative power of the nucleus, the effects of radiative feedback can be detected over the entire host galaxy and sometimes well into the intergalactic space. In this paper we model the observed size-luminosity relationship of the narrow-line regions (NLRs) of AGN. We model the NLR as a collection of clouds in pressure equilibrium with the ionizing radiation, with each cloud producing line emission calculated by Cloudy. The sizes of the NLRs of powerful quasars are reproduced without any free parameters, as long as they contain massive (105M⊙ to 107M⊙) ionization-bounded clouds. At lower AGN luminosities the observed sizes are larger than the model sizes, likely due to additional unmodeled sources of ionization (e.g., star formation). We find that the observed saturation of sizes at ˜10kpc which is observed at high AGN luminosities (Lion ≃ 1046erg/s) is naturally explained by optically thick clouds absorbing the ionizing radiation and preventing illumination beyond a critical distance. Using our models in combination with observations of the [O III]/IR ratio and the [O III] size - IR luminosity relationship, we calculate the covering factor of the obscuring torus (and therefore the type 2 fraction within the quasar population) to be f = 0.5, though this is likely an upper bound. Finally, because the gas behind the ionization front is invisible in ionized gas transitions, emission-based NLR mass calculations underestimate the mass of the NLR and therefore of the energetics of ionized-gas winds.

Nucleotide sequences of the cDNAs encoding the V-regions of H- and L-chains of a human monoclonal antibody with broad reactivity to malignant tumor cells

Energy Technology Data Exchange (ETDEWEB)

Kishimoto, Toshimitsu; Okajima, Hideki; Okumoto, Takeki [Yoshitomi Pharmaceutical Industries, Ltd., Saitama (Japan); Taniguchi, Masaru [Chiba Univ. (Japan)

1989-06-12

The human monoclonal antibody secreted from 4G12 hybridoma cells has broad reactivity to malignant tumor cells, especially for lung squamous cell carcinomas, and recognizes a new tumor-associated and differentiation antigen. The antigen detected by 4G12 is a glycoprotein with MW 195,000 and MW 65,000 under nonreducing and reducing conditions, respectively. Screening of a 4G12 {lambda}gt10 cDNA library with constant region probes for human immunoglobulin yielded full length clones for H- and L-chains. Nucleotide sequences revealed that subtypes of the variable regions were V{sub HIII} and {lambda}{sub 1}, respectively.

Wolf-Rayet stars featured in emission-line galaxies

International Nuclear Information System (INIS)

Kunth, D.

1982-01-01

In the galaxy Tololo 3 (NGC 3125) recent observations by the author and Sargent (1981) have revealed the presence of an unusual strong and broad He II 4686 emission. The origin of this line together with some nitrogen lines (e.g. N V 4620 and N III 4638) is attributed to Wolf-Rayet stars, mostly of WN types. (Auth.)

High-resolution Laboratory Measurements of Coronal Lines near the Fe IX Line at 171 Å

Science.gov (United States)

Beiersdorfer, Peter; Träbert, Elmar

2018-02-01

We present high-resolution laboratory measurements in the spectral region between 165 and 175 Å that focus on the emission from various ions of C, O, F, Ne, S, Ar, Fe, and Ni. This wavelength region is centered on the λ171 Fe IX channel of the Atmospheric Imaging Assembly on the Solar Dynamics Observatory, and we place special emphasis on the weaker emission lines of Fe IX predicted in this region. In general, our measurements show a multitude of weak lines missing in the current databases, where the emission lines of Ni are probably most in need of further identification and reclassification. We also find that the wavelengths of some of the known lines need updating. Using the multi-reference Møller–Plesset method for wavelength predictions and collisional-radiative modeling of the line intensities, we have made tentative assignments of more than a dozen lines to the spectrum of Fe IX, some of which have formerly been identified as Fe VII, Fe XIV, or Fe XVI lines. Several Fe features remain unassigned, although they appear to be either Fe VII or Fe X lines. Further work will be needed to complete and correct the spectral line lists in this wavelength region.

Broad-Band Analysis of Polar Motion Excitations

Science.gov (United States)

Chen, J.

2016-12-01

Earth rotational changes, i.e. polar motion and length-of-day (LOD), are driven by two types of geophysical excitations: 1) mass redistribution within the Earth system, and 2) angular momentum exchange between the solid Earth (more precisely the crust) and other components of the Earth system. Accurate quantification of Earth rotational excitations has been difficult, due to the lack of global-scale observations of mass redistribution and angular momentum exchange. The over 14-years time-variable gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) have provided a unique means for quantifying Earth rotational excitations from mass redistribution in different components of the climate system. Comparisons between observed Earth rotational changes and geophysical excitations estimated from GRACE, satellite laser ranging (SLR) and climate models show that GRACE-derived excitations agree remarkably well with polar motion observations over a broad-band of frequencies. GRACE estimates also suggest that accelerated polar region ice melting in recent years and corresponding sea level rise have played an important role in driving long-term polar motion as well. With several estimates of polar motion excitations, it is possible to estimate broad-band noise variance and noise power spectra in each, given reasonable assumptions about noise independence. Results based on GRACE CSR RL05 solutions clearly outperform other estimates with the lowest noise levels over a broad band of frequencies.

Representativeness of the LifeLines Cohort Study.

Directory of Open Access Journals (Sweden)

Bart Klijs

Full Text Available LifeLines is a large prospective population-based three generation cohort study in the north of the Netherlands. Different recruitment strategies were adopted: recruitment of an index population via general practitioners, subsequent inclusion of their family members, and online self-registration. Our aim was to investigate the representativeness of the adult study population at baseline and to evaluate differences in the study population according to recruitment strategy.Demographic characteristics of the LifeLines study population, recruited between 2006-2013, were compared with the total adult population in the north of the Netherlands as registered in the Dutch population register. Socioeconomic characteristics, lifestyle, chronic diseases, and general health were further compared with participants of the Permanent Survey of Living Conditions within the region (2005-2011, N = 6,093. Differences according to recruitment strategy were assessed.Compared with the population of the north of the Netherlands, LifeLines participants were more often female, middle aged, married, living in a semi-urban place and Dutch native. Adjusted for differences in demographic composition, in LifeLines a smaller proportion had a low educational attainment (5% versus 14% or had ever smoked (54% versus 66%. Differences in the prevalence of various chronic diseases and low general health scores were mostly smaller than 3%. The age profiles of the three recruitment groups differed due to age related inclusion criteria of the recruitment groups. Other differences according to recruitment strategy were small.Our results suggest that, adjusted for differences in demographic composition, the LifeLines adult study population is broadly representative for the adult population of the north of the Netherlands. The recruitment strategy had a minor effect on the level of representativeness. These findings indicate that the risk of selection bias is low and that risk estimates

A DEEP CHANDRA ACIS STUDY OF NGC 4151. II. THE INNERMOST EMISSION LINE REGION AND STRONG EVIDENCE FOR RADIO JET-NLR CLOUD COLLISION

International Nuclear Information System (INIS)

Wang Junfeng; Fabbiano, Giuseppina; Elvis, Martin; Risaliti, Guido; Karovska, Margarita; Zezas, Andreas; Mundell, Carole G.

2011-01-01

We have studied the X-ray emission within the inner ∼150 pc radius of NGC 4151 by constructing high spatial resolution emission line images of blended O VII, O VIII, and Ne IX. These maps show extended structures that are spatially correlated with the radio outflow and optical [O III] emission. We find strong evidence for jet-gas cloud interaction, including morphological correspondences with regions of X-ray enhancement, peaks of near-infrared [Fe II] emission, and optical clouds. In these regions, moreover, we find evidence of elevated Ne IX/O VII ratios; the X-ray emission of these regions also exceeds that expected from nuclear photoionization. Spectral fitting reveals the presence of a collisionally ionized component. The thermal energy of the hot gas suggests that ∼> 0.1% of the estimated jet power is deposited into the host interstellar medium through interaction between the radio jet and the dense medium of the circumnuclear region. We find possible pressure equilibrium between the collisionally ionized hot gas and the photoionized line-emitting cool clouds. We also obtain constraints on the extended iron and silicon fluorescent emission. Both lines are spatially unresolved. The upper limit on the contribution of an extended emission region to the Fe Kα emission is ∼< 5% of the total, in disagreement with a previous claim that 65% of the Fe Kα emission originates in the extended narrow line region.

Very large array and green bank telescope observations of Orion B (NGC 2024, W12): photodissociation region properties and magnetic field

Energy Technology Data Exchange (ETDEWEB)

Roshi, D. Anish [National Radio Astronomy Observatory, Charlottesville and Green Bank, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Goss, W. M. [National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States); Jeyakumar, S., E-mail: aroshi@nrao.edu, E-mail: mgoss@nrao.edu, E-mail: sjk@astro.ugto.mx [Departamento de Astronomía, Universidad de Guanajuato, AP 144, Guanajuato CP 36000 (Mexico)

2014-10-01

shows narrow (1.7 km s{sup –1}) and broad (33 km s{sup –1}) line features. The narrow line has spatial distribution and central velocity (∼9 km s{sup –1}) similar to that of the foreground carbon line emission, suggesting that they are associated. Modeling the narrow H166α emission provides physical properties T {sub PDR} ∼ 50 K, n{sub e}{sup PDR}∼4 cm{sup –3}, and l ∼ 0.01 pc and implies an ionization fraction of ∼10{sup –4}. The broad H166α line originates from the H II region. The X166α line has a different spatial distribution compared to other RRLs observed toward NGC 2024 and is probably associated with cold dust clouds. Based on the expected low depletion of sulfur in such clouds and the –8.1 km s{sup –1} velocity separation between the X166α and C166α lines, we interpret that the X166α transition arises from sulfur.

Very large array and green bank telescope observations of Orion B (NGC 2024, W12): photodissociation region properties and magnetic field

International Nuclear Information System (INIS)

Roshi, D. Anish; Goss, W. M.; Jeyakumar, S.

2014-01-01

We present images of C110α and H110α radio recombination line (RRL) emission at 4.8 GHz and images of H166α, C166α, and X166α RRL emission at 1.4 GHz, observed toward the star-forming region NGC 2024. The 1.4 GHz image with angular resolution ∼70'' is obtained using Very Large Array (VLA) data. The 4.8 GHz image with angular resolution ∼17'' is obtained by combining VLA and Green Bank Telescope data in order to add the short and zero spacing data in the uv plane. These images reveal that the spatial distributions of C110α line emission is confined to the southern rim of the H II region close to the ionization front whereas the C166α line emission is extended in the north-south direction across the H II region. The LSR velocity of the C110α line is 10.3 km s –1 similar to that of lines observed from molecular material located at the far side of the H II region. This similarity suggests that the photodissociation region (PDR) responsible for C110α line emission is at the far side of the H II region. The LSR velocity of C166α is 8.8 km s –1 . This velocity is comparable with the velocity of molecular absorption lines observed from the foreground gas, suggesting that the PDR is at the near side of the H II region. Non-LTE models for carbon line-forming regions are presented. Typical properties of the foreground PDR are T PDR ∼ 100 K, n e PDR ∼5 cm –3 , n H ∼ 1.7 × 10 4 cm –3 , and path length l ∼ 0.06 pc, and those of the far side PDR are T PDR ∼ 200 K, n e PDR ∼ 50 cm –3 , n H ∼ 1.7 × 10 5 cm –3 , and l ∼ 0.03 pc. Our modeling indicates that the far side PDR is located within the H II region. We estimate the magnetic field strength in the foreground PDR to be 60 μG and that in the far side PDR to be 220 μG. Our field estimates compare well with the values obtained from OH Zeeman observations toward NGC 2024. The H166α spectrum shows narrow (1.7 km s –1 ) and broad (33 km s –1 ) line features. The

A Strategy for Generating a Broad-Spectrum Monoclonal Antibody and Soluble Single-Chain Variable Fragments against Plant Potyviruses

Science.gov (United States)

Liu, Han-Lin; Lin, Wei-Fang; Hu, Wen-Chi; Lee, Yung-An

2015-01-01

Potyviruses are major pathogens that often cause mixed infection in calla lilies. To reduce the time and cost of virus indexing, a detection method for the simultaneous targeting of multiple potyviruses was developed by generating a broad-spectrum monoclonal antibody (MAb) for detecting the greatest possible number of potyviruses. The conserved 121-amino-acid core regions of the capsid proteins of Dasheen mosaic potyvirus (DsMV), Konjak mosaic potyvirus (KoMV), and Zantedeschia mild mosaic potyvirus (ZaMMV) were sequentially concatenated and expressed as a recombinant protein for immunization. After hybridoma cell fusion and selection, one stable cell line that secreted a group-specific antibody, named C4 MAb, was selected. In the reaction spectrum test, the C4 MAb detected at least 14 potyviruses by indirect enzyme-linked immunosorbent assay (I-ELISA) and Western blot analysis. Furthermore, the variable regions of the heavy (VH) and light (VL) chains of the C4 MAb were separately cloned and constructed as single-chain variable fragments (scFvs) for expression in Escherichia coli. Moreover, the pectate lyase E (PelE) signal peptide of Erwinia chrysanthemi S3-1 was added to promote the secretion of C4 scFvs into the medium. According to Western blot analysis and I-ELISA, the soluble C4 scFv (VL-VH) fragment showed a binding specificity similar to that of the C4 MAb. Our results demonstrate that a recombinant protein derived from fusion of the conserved regions of viral proteins has the potential to produce a broad-spectrum MAb against a large group of viruses and that the PelE signal peptide can improve the secretion of scFvs in E. coli. PMID:26209665

A postmenopausal woman with sciatica from broad ligament leiomyoma: a case report.

Science.gov (United States)

Tsai, Ya-Chu May

2016-10-31

Unilateral lower abdominal pain and/or sciatic nerve pain is a common presentation in the elderly population. The prevalence of broad ligament leiomyoma is leiomyomas to be clinically significant. Thus, we highlight a case of symptomatic broad ligament leiomyoma in a postmenopausal woman whose symptoms improved after definitive treatment. A 62-year-old postmenopausal Macedonian woman was referred to our gynecological department with unexplained pain in her left leg and left iliac fossa region on walking. There was minimal relief with increasing analgesia use prescribed by the family physician. Investigations revealed an ipsilateral adnexal mass and subsequent treatment with laparoscopic broad ligament myomectomy helped to alleviate her symptoms. Our case highlights the importance of staying mindful of alternate diagnoses when presented with a common presentation of iliac fossa pain and pain in the leg. Although broad ligament leiomyomas are benign tumors, the uncommon symptomatic presentation led us to report and focus some attention on this type of tumor.

FT-IR measurements of NH3 in the 1.5 μm region: line positions, intensities and their quantum assignments

Science.gov (United States)

Sung, K.; Brown, L. R.; Huang, X.; Schwenke, D. W.; Lee, T. J.

2011-12-01

As part of an effort to provide a complete set of spectroscopic line parameters of NH3 in the 1.5 μm region, we have analyzed the laboratory spectra recorded at various temperatures (200 - 299 K) with the McMath-Pierce Fourier transform spectrometer (FTS) on Kitt Peak Observatory in Arizona. The integrated sum of observed line strengths is measured to be 4.7×10-19 cm/molecule in the 6300 - 7000 cm-1 region. In this poster, we present line positions and strengths for the lines from four strong bands (2v1, 2v3, v1+v3, v1+2v4 and v3+2v4), which contribute more than 65% of opacity in the region. Lower state energies and quantum assignments determined by constructing combination differences are also presented. A theoretical IR linelist (X. Huang, D. W. Schwenke, and T. J. Lee. J. Chem. Phys., 134, 044320/044321, 2011) built upon the recent HSL-2 potential energy surface (nonadiabatic corrections included) is complementarily used for the quantum assignments. This work will support spectroscopic studies of atmospheres of outer planets, low mass brown dwarfs, and possibly extrasolar planets, in the 1.5 μm region (the H-band), where ammonia is one of significant opacity sources. (Research described in this talk was performed at Jet Propulsion Laboratory, California Institute of Technology, and was supported by the Planetary Atmospheric Research Program under the National Aeronautics and Space Administration. The AMES group acknowledges support from the NASA APRA & Herschel GO Program, and X.H. acknowledges the support by NASA/SETI Institute Co-operative Agreement.)

Stability of emission line clouds in active galactic nuclei

International Nuclear Information System (INIS)

Krinsky, I.S.

1989-01-01

A numerical model was developed for a Quasar Stellar Object (QSO) broad emission line cloud (ELC) imbedded within a confining hot intercloud medium (HIM) for the purpose of studying its stability to perturbations in its temperature and density. A self-consistent model in radiative, pressure and thermal equilibrium is presented. The effect of trapped line radiation pressure is also included with the total pressure (particle plus radiation) held constant. The equilibrium model is found to have regions with radiation pressure exceeding gas pressure. Energy transport includes the effects of an external broken power law continuum and thermal conduction of heat from the HIM. Conduction is found to be unimportant to the total energy budget of the cloud, but is important to the dynamics of the ELC/HIM interface. Independent of the ELC/HIM model, an extension of second order probabilistic radiative transfer that treats the diffuse radiation field as composed of two oppositely directed streams is presented. The high ionization zone of the ELC is found to be unstable to radiatively driven sound waves. Both the external radiation field and the force of trapped line radiation are potential sources for driving the growth of sound waves. The final picture that emerges is that the ELC must be in a constant state of flux

Numerical simulations of sheared magnetic lines at the solar null line

Science.gov (United States)

Kuźma, B.; Murawski, K.; Solov'ev, A.

2015-05-01

Aims: We perform numerical simulations of sheared magnetic lines at the magnetic null line configuration of two magnetic arcades that are settled in a gravitationally stratified and magnetically confined solar corona. Methods: We developed a general analytical model of a 2.5D solar atmospheric structure. As a particular application of this model, we adopted it for the curved magnetic field lines with an inverted Y shape that compose the null line above two magnetic arcades, which are embedded in the solar atmosphere that is specified by the realistic temperature distribution. The physical system is described by 2.5D magnetohydrodynamic equations that are numerically solved by the FLASH code. Results: The magnetic field line shearing, implemented about 200 km below the transition region, results in Alfvén and magnetoacoustic waves that are able to penetrate solar coronal regions above the magnetic null line. As a result of the coupling of these waves, partial reflection from the transition region and scattering from inhomogeneous regions the Alfvén waves experience fast attenuation on time scales comparable to their wave periods, and the physical system relaxes in time. The attenuation time grows with the large amplitude and characteristic growing time of the shearing. Conclusions: By having chosen a different magnetic flux function, the analytical model we devised can be adopted to derive equilibrium conditions for a diversity of 2.5D magnetic structures in the solar atmosphere. Movie associated to Fig. 5 is available in electronic form at http://www.aanda.org

THE DISCOVERY OF RAMAN SCATTERING IN H II REGIONS

Energy Technology Data Exchange (ETDEWEB)

Dopita, Michael A.; Nicholls, David C.; Sutherland, Ralph S.; Kewley, Lisa J.; Groves, Brent A., E-mail: Michael.Dopita@anu.edu.au [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia)

2016-06-10

We report here on the discovery of faint extended wings of H α observed out to an apparent velocity of ∼7600 km s{sup −1} in the Orion Nebula (M42) and in five H ii regions in the Large and the Small Magellanic Clouds. We show that these wings are caused by Raman scattering of both the O i and Si ii resonance lines and stellar continuum UV photons with H i followed by radiative decay to the H i n = 2 level. The broad wings also seen in H β and in H γ result from Raman scattering of the UV continuum in the H i n = 4 and n = 5 levels, respectively. The Raman scattering fluorescence is correlated with the intensity of the narrow permitted lines of O i and Si ii. In the case of Si ii, this is explained by radiative pumping of the same 1023.7 Å resonance line involved in the Raman scattering by the Ly β radiation field. The subsequent radiative cascade produces enhanced Si ii λλ 5978.9, 6347.1, and 6371.4 Å permitted transitions. Finally, we show that in O i, radiative pumping of the 1025.76 Å resonance line by the Lyman series radiation field is also the cause of the enhancement in the permitted lines of this species lying near H α in wavelength, but here the process is a little more complex. We argue that all these processes are active in the zone of the H ii region near the ionization front.

Hemodiafiltration using pre-dilutional on-line citrate dialysate: A new technique for regional citrate anticoagulation: A feasibility study

Directory of Open Access Journals (Sweden)

Radhouane Bousselmi

2015-01-01

Full Text Available A prospective, observational, feasibility study was carried out on four patients with end-stage renal failure undergoing bicarbonate hemodialysis to study the feasibility of an on-line hemodiafiltration technique using a citrate dialysate with pre-dilutional infusion of citrate as a technique for regional citrate anticoagulation. All patients had contraindication to systemic heparin anticoagulation. The dialysis technique consisted of an on-line hemodiafiltration with a citrate dialysate without calcium using a Fresenius 4008S dialysis machine and Fresenius Polysulfone F60 dialyzers. The infusion solution was procured directly from the dialysate and was infused into the arterial line. To avoid the risk of hypocalcemia, calcium gluconate was infused to the venous return line. The study was carried out in two stages. During the first stage, the citrate infusion rate was 80 mL/min and the calcium infusion rate was 9 mmol/h. At the second stage, the rates were 100 mL/min and 11 mmol/h, respectively. The primary endpoint of this study was the incidence of thrombosis in the extracorporeal blood circuit and/or the dialyzer. A total of 78 sessions were conducted. All the sessions were well tolerated clinically and there were no major incidents in any of the four patients. At the first stage of the study, there were five incidences of small clots in the venous blood chamber, an incidence of extracorporeal blood circuit thrombosis of 12.5%. At the second stage of the study, no cases of extracorporeal blood circuit or dialyzer thrombosis were noted. Hemodiafiltration with on-line citrate dialysate infusion to the arterial line is safe and allows an effective regional anticoagulation of the extracorporeal blood circuit without the need for systemic anticoagulation.

Structure, shape, and evolution of radiatively accelerated QSO emission-line clouds

International Nuclear Information System (INIS)

Blumenthal, G.R.; Mathews, W.G.

1979-01-01

The possibility that the broad emission-line regions of QSOs and active galactic nuclei are formed by a multitude of small clouds which are radiatively accelerated is discussed. Although this model is by no means certain at present, it has four virtues: (1) Observed emission-line widths can be produced with observationally allowed electron densities, UV luminosities, and ionization levels. (2) The acceleration force is coherent in each cloud are found. (3) Reasonable line profiles can result for all emission lines. (4) Photoionization of hydrogen accounts for both heating and acceleration of the emission-line gas. A self-consistent model is developed for the structure, shape, and evolution of radiatively accelerated clouds. The shape varies with cloud mass, and two distinct types of clouds. Fully ionized clouds of very low mass approach a nearly spherical shape. However, all clouds having masses greater than some critical mass adopt a ''pancake'' shape. The condition for constant cloud mass in the cloud frame is shown to be equivalent to the equation of motion of a cloud in the rest frame of the QSO. The emission-line profiles can be sensitive to radial variations in the properties of the intercloud medium, and those properties that correspond to observed profiles are discussed. Finally, the covering factor of a system of pancake clouds is estimated along with the total number of clouds required--approximately 10 14 clouds in each QSO

Structure and Dynamics of Cool Flare Loops Observed by the Interface Region Imaging Spectrograph

Energy Technology Data Exchange (ETDEWEB)

Mikuła, K.; Berlicki, A. [Astronomical Institute, University of Wrocław, Kopernika 11, 51–622 Wrocław (Poland); Heinzel, P.; Liu, W., E-mail: mikula@astro.uni.wroc.pl [Astronomical Institute, The Czech Academy of Sciences, 25165 Ondřejov (Czech Republic)

2017-08-10

Flare loops were well observed with the Interface Region Imaging Spectrograph ( IRIS ) during the gradual phase of two solar flares on 2014 March 29 and 2015 June 22. Cool flare loops are visible in various spectral lines formed at chromospheric and transition-region temperatures and exhibit large downflows which correspond to the standard scenario. The principal aim of this work is to analyze the structure and dynamics of cool flare loops observed in Mg ii lines. Synthetic profiles of the Mg ii h line are computed using the classical cloud model and assuming a uniform background intensity. In this paper, we study novel IRIS NUV observations of such loops in Mg ii h and k lines and also show the behavior of hotter lines detected in the FUV channel. We obtained the spatial evolution of the velocities: near the loop top, the flow velocities are small and they are increasing toward the loop legs. Moreover, from slit-jaw image (SJI) movies, we observe some plasma upflows into the loops, which are also detectable in Mg ii spectra. The brightness of the loops systematically decreases with increasing flow velocity, and we ascribe this to the effect of Doppler dimming, which works for Mg ii lines. Emission profiles of Mg ii were found to be extremely broad, and we explain this through the large unresolved non-thermal motions.

Interrogating Seyferts with NebulaBayes: Spatially Probing the Narrow-line Region Radiation Fields and Chemical Abundances

Science.gov (United States)

Thomas, Adam D.; Dopita, Michael A.; Kewley, Lisa J.; Groves, Brent A.; Sutherland, Ralph S.; Hopkins, Andrew M.; Blanc, Guillermo A.

2018-04-01

NebulaBayes is a new Bayesian code that implements a general method of comparing observed emission-line fluxes to photoionization model grids. The code enables us to extract robust, spatially resolved measurements of abundances in the extended narrow-line regions (ENLRs) produced by Active Galactic Nuclei (AGN). We observe near-constant ionization parameters but steeply radially declining pressures, which together imply that radiation pressure regulates the ENLR density structure on large scales. Our sample includes four “pure Seyfert” galaxies from the S7 survey that have extensive ENLRs. NGC 2992 shows steep metallicity gradients from the nucleus into the ionization cones. An inverse metallicity gradient is observed in ESO 138-G01, which we attribute to a recent gas inflow or minor merger. A uniformly high metallicity and hard ionizing continuum are inferred across the ENLR of Mrk 573. Our analysis of IC 5063 is likely affected by contamination from shock excitation, which appears to soften the inferred ionizing spectrum. The peak of the ionizing continuum E peak is determined by the nuclear spectrum and the absorbing column between the nucleus and the ionized nebula. We cannot separate variation in this intrinsic E peak from the effects of shock or H II region contamination, but E peak measurements nevertheless give insights into ENLR excitation. We demonstrate the general applicability of NebulaBayes by analyzing a nuclear spectrum from the non-active galaxy NGC 4691 using a H II region grid. The NLR and H II region model grids are provided with NebulaBayes for use by the astronomical community.

Off-axis irradiation and the polarization of broad emission lines in active galactic nuclei

Czech Academy of Sciences Publication Activity Database

Goosmann, R. W.; Gaskell, C.M.; Marin, Frederic

2014-01-01

Roč. 54, č. 7 (2014), s. 1341-1346 ISSN 0273-1177 Institutional support: RVO:67985815 Keywords : polarization * radiative transfer * R line profiles Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics OBOR OECD: Astronomy (including astrophysics,space science) Impact factor: 1.358, year: 2014

On open and closed field line regions in Tsyganenko's field model and their possible associations with horse collar auroras

Science.gov (United States)

Birn, J.; Hones, E. W., Jr.; Craven, J. D.; Frank, L. A.; Elphinstone, R. D.; Stern, D. P.

1991-01-01

The boundary between open and closed field lines is investigated in the empirical Tsyganenko (1987) magnetic field model. All field lines extending to distances beyond -70 R(E), the tailward velocity limit of the Tsyganenko model are defined as open, while all other field lines, which cross the equatorial plane earthward of -70 R(E) and are connected with the earth at both ends, are assumed closed. It is found that this boundary at the surface of the earth, identified as the polar cap boundary, can exhibit the arrowhead shape, pointed toward the sun, which is found in horse collar auroras. For increasing activity levels, the polar cap increases in area and becomes rounder, so that the arrowhead shape is less pronounced. The presence of a net B(y) component can also lead to considerable rounding of the open flux region. The arrowhead shape is found to be closely associated with the increase of B(z) from the midnight region to the flanks of the tail, consistent with a similar increase of the plasma sheet thickness.

The precipitation synthesis of broad-spectrum UV absorber nanoceria

International Nuclear Information System (INIS)

Nurhasanah, Iis; Sutanto, Heri; Puspaningrum, Nurul Wahyu

2013-01-01

In this paper the possibility of nanoceria as broad-spectrum UV absorber was evaluated. Nanoceria were synthesized by precipitation process from cerium nitrate solution and ammonium hydroxide as precipitant agent. Isopropanol was mixed with water as solvent to prevent hard agglomeration. The structure of resulting nanoceria was characterized by x-ray diffractometer (XRD). The transparency in the visible light and efficiency of protection in UV A region were studied using ultraviolet-visible (UV - Vis) spectrophotometer. The results show that nanoceria possess good tranparency in visible light and high UV light absorption. The critical absorption wavelenght of 368 nm was obtained which is desirable for excellent broad-spectrum protection absorbers. Moreover, analysis of photodegradation nanoceria to methylene blue solution shows poor photocatalytic activity. It indicates that nanoceria suitable for used as UV absorber in personal care products

Quantum-mechanical vs. semi-classical spectral-line widths and shifts from the line core in the non-impact region for the Ar-perturbed/ K-radiator system

International Nuclear Information System (INIS)

Kreye, W.C.

2007-01-01

New quantum-mechanical (QM) and semi-classical (SC) shifts (d's) and widths (HWHM's, w's) were measured from the line core of computed full spectral-line shapes for the Ar-perturbed/K-radiator system (K/Ar). The initial state of our model was based on a 4p 2 P 3/2,1/2 pseudo-potential for the K/Ar system, and the final state on a zero potential. The Fourier transform of the line shape formed the basis for the computations. Excellent agreement was found between the QM and SC values of d and of w in a high-pressure (P) non-impact region, which was characterized by a √P dependence of w and a P dependence of d. These agreements were shown to be another example of a correspondence between classical (SC) quantities and QM quantities in the limit of large quantum numbers. Typically at P=1x10 6 Torr and T=400 K, w QM =448 cm -1 and w SC =479 cm -1 , where the deviation from the mean is ±3.3%. Also, d QM =-3815 cm -1 and d SC =-3716 cm -1 , where the deviation from the mean is ±1.3%. A new general method was formulated which yielded a definite pressure P 0 , which was defined as an upper limit to the low-pressure impact approximation and a lower limit to the non-impact region

History of Lipizzan horse maternal lines as revealed by mtDNA analysis

Directory of Open Access Journals (Sweden)

Dovč Peter

2002-09-01

Full Text Available Abstract Sequencing of the mtDNA control region (385 or 695 bp of 212 Lipizzans from eight studs revealed 37 haplotypes. Distribution of haplotypes among studs was biased, including many private haplotypes but only one haplotype was present in all the studs. According to historical data, numerous Lipizzan maternal lines originating from founder mares of different breeds have been established during the breed's history, so the broad genetic base of the Lipizzan maternal lines was expected. A comparison of Lipizzan sequences with 136 sequences of domestic- and wild-horses from GenBank showed a clustering of Lipizzan haplotypes in the majority of haplotype subgroups present in other domestic horses. We assume that haplotypes identical to haplotypes of early domesticated horses can be found in several Lipizzan maternal lines as well as in other breeds. Therefore, domestic horses could arise either from a single large population or from several populations provided there were strong migrations during the early phase after domestication. A comparison of Lipizzan haplotypes with 56 maternal lines (according to the pedigrees showed a disagreement of biological parentage with pedigree data for at least 11% of the Lipizzans. A distribution of haplotype-frequencies was unequal (0.2%–26%, mainly due to pedigree errors and haplotype sharing among founder mares.

Exploring Conservation Options in the Broad-Leaved Korean Pine Mixed Forest of the Changbai Mountain Region

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Lin Ma

2015-05-01

Full Text Available The broad-leaved Korean pine (Pinus koraiensis mixed forest (BKPF is one of the most biodiverse zonal communities in the northern temperate zone. Changbai Mountain in northeastern China contains one of the largest BKPFs in the region. The government of China has established a network of 23 nature reserves to protect the BKPF and the species that depend on it for habitat, including the endangered Siberian tiger (Panthera tigris altaica. This study used the conservation planning software C-Plan to calculate the irreplaceability value of each unit to assess how efficiently and comprehensively the existing conservation network supports biodiversity and to identify gap areas that, if integrated into the network, would expand its protection capability. Results show a number of high-conservation-value planning units concentrated along certain ridges. The existing conservation network is structured such that the habitats of only 24 species (out of a total of 75 achieve established conservation targets. Of the other 51 species, 20 achieve less than 50% of their conservation targets. However, expanding the network to include high-conservation-value gap areas could achieve conservation targets for 64 species and could provide different degrees of protection to the other 11 species. Using C-Plan software can guide decision-making to expand the conservation network in this most precious of mountainous ecological zones.

The magnetic field near power lines in the Moscow region: the results of measurements and their analyze

Directory of Open Access Journals (Sweden)

Prokofyeva A.S.

2014-12-01

Full Text Available The aim: to analyze the real power frequency magnetic field (50 Hz values near power lines. The material. Long-term measurements of the power frequency magnetic field (50 Hz near power lines of 110 kV, 220 kVand 500 kVin the Moscow region. Methods. Measurements were made by tracks which were perpendicular to the wires. Length of tracks was up to 40 m. Sensor of measurer was located on 1.8 m under the ground. General quantity of measurement points were 1103. The results. Was obtained general characteristics of real values of strength of electric field and values of magnetic flux density depending to distance to the projection last wire near power lines. Conclusion. Analysis of the results has the values of the magnetic field of power lines correspond to the Russian rules in all cases. Using additional World Health Organization safety criteria for magnetic fields (the class of carcinogenic risks 2B requires the expansion of the health safety zone 2-3 times.

FERO (Finding Extreme Relativistic Objects): statistics of relativistic broad Fe Kalpha lines in AGN

Czech Academy of Sciences Publication Activity Database

Longinotti, A. L.; de La Calle, I.; Bianchi, S.; Guainazzi, M.; Dovčiak, Michal

2008-01-01

Roč. 79, č. 1 (2008), s. 259-261 ISSN 0037-8720. [ Simbol -X: The hard X-ray Universe in focus. Bologna, 14.05.2007-16.05.2007] Institutional research plan: CEZ:AV0Z10030501 Keywords : active galaxies * X-raylLines-iron Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

A NEW RADIO RECOMBINATION LINE MASER OBJECT TOWARD THE MonR2 H II REGION

Energy Technology Data Exchange (ETDEWEB)

Jimenez-Serra, I.; Zhang, Q.; Dierickx, M.; Patel, N. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Baez-Rubio, A.; Rivilla, V. M.; Martin-Pintado, J., E-mail: ijimenez-serra@cfa.harvard.edu, E-mail: qzhang@cfa.harvard.edu, E-mail: mdierickx@cfa.harvard.edu, E-mail: npatel@cfa.harvard.edu, E-mail: ryvendel@gmail.com, E-mail: jmartin@cab.inta-csic.es, E-mail: baezra@cab.inta-csic.es [Centro de Astrobiologia (CSIC/INTA), Ctra. de Torrejon a Ajalvir km 4, E-28850 Torrejon de Ardoz, Madrid (Spain)

2013-02-10

We report the detection of a new radio recombination line (RRL) maser object toward the IRS2 source in the MonR2 ultracompact H II region. The continuum emission at 1.3 mm and 0.85 mm and the H30{alpha} and H26{alpha} lines were observed with the Submillimeter Array (SMA) at angular resolutions of {approx}0.''5-3''. The SMA observations show that the MonR2-IRS2 source is very compact and remains unresolved at spatial scales {<=}400 AU. Its continuum power spectrum at millimeter wavelengths is almost flat ({alpha} = -0.16, with S{sub {nu}}{proportional_to}{nu}{sup {alpha}}), indicating that this source is dominated by optically thin free-free emission. The H30{alpha} and H26{alpha} RRL emission is also compact and peaks toward the position of the MonR2-IRS2 source. The measured RRL profiles are double peaked with the H26{alpha} line showing a clear asymmetry in its spectrum. Since the derived line-to-continuum flux ratios ({approx}80 and 180 km s{sup -1} for H30{alpha} and H26{alpha}, respectively) exceed the LTE predictions, the RRLs toward MonR2-IRS2 are affected by maser amplification. The amplification factors are, however, smaller than those found toward the emission-line star MWC349A, indicating that MonR2-IRS2 is a weakly amplified maser. Radiative transfer modeling of the RRL emission toward this source shows that the RRL masers arise from a dense and collimated jet embedded in a cylindrical ionized wind, oriented nearly along the direction of the line of sight. High-angular resolution observations at submillimeter wavelengths are needed to unveil weakly amplified RRL masers in very young massive stars.

Constraints on Black Hole Spin in a Sample of Broad Iron Line AGN

Science.gov (United States)

Brenneman, Laura W.; Reynolds, Christopher S.

2008-01-01

We present a uniform X-ray spectral analysis of nine type-1 active galactic nuclei (AGN) that have been previously found to harbor relativistically broadened iron emission lines. We show that the need for relativistic effects in the spectrum is robust even when one includes continuum "reflection" from the accretion disk. We then proceed to model these relativistic effects in order to constrain the spin of the supermassive black holes in these AGN. Our principal assumption, supported by recent simulations of geometrically-thin accretion disks, is that no iron line emission (or any associated Xray reflection features) can originate from the disk within the innermost stable circular orbit. Under this assumption, which tends to lead to constraints in the form of lower limits on the spin parameter, we obtain non-trivial spin constraints on five AGN. The spin parameters of these sources range from moderate (a approximates 0.6) to high (a > 0.96). Our results allow, for the first time, an observational constraint on the spin distribution function of local supermassive black holes. Parameterizing this as a power-law in dimensionless spin parameter (f(a) varies as absolute value of (a) exp zeta), we present the probability distribution for zeta implied by our results. Our results suggest 90% and 95% confidence limits of zeta > -0.09 and zeta > -0.3 respectively.

The 2010 Broad Prize

Science.gov (United States)

Education Digest: Essential Readings Condensed for Quick Review, 2011

2011-01-01

A new data analysis, based on data collected as part of The Broad Prize process, provides insights into which large urban school districts in the United States are doing the best job of educating traditionally disadvantaged groups: African-American, Hispanics, and low-income students. Since 2002, The Eli and Edythe Broad Foundation has awarded The…

Hints on the Broad Line Region Structure of Quasars at High and Low Luminosities

Directory of Open Access Journals (Sweden)

Marziani Paola

2011-09-01

Full Text Available Quasars show a considerable spectroscopic diversity. However, the variety of quasar spectra at low redshifts is non-random: a principal component analysis applied to large samples customarily identifies two main eigenvectors. In this contribution we show that the range of quasar optical spectral properties observed at low-z and associated with the first eigenvector is preserved up to z ≈ 2 in a sample of high luminosity quasars. We also describe two major luminosity effects.

How broad and deep is the region of chemical alteration of oceanic plates at trenches?

Science.gov (United States)

Ranero, C. R.; Grevemeyer, I.; Barckhausen, U.

2017-12-01

Different lines of evidence indicate that oceanic plates are affected by pervasive bending-related deformation approaching ocean trenches. Results from active-seismic work support that deformation provides paths for exchange between hydrosphere and lithosphere, possibly causing chemical alteration of the incoming lithosphere. Much work focused on the potential transformation of peridotite to serpentine in the uppermost mantle of incoming plates, but there is no consensus on the region where it may occur or the intensity of alteration, let alone on limiting factors for the process. Teleseismic (large-great) earthquakes with normal-fault mechanism in the outer rise region have been often called to speculate on the depth of penetration of plate hydration. However, large-great outer-rise earthquakes may be related to stress changes due to slab pull after decoupling along the inter-plate boundary, and not necessarily controlled by bending stresses only. If so, the majority of the time the depth of water percolation may be related to local bending stresses expressed by micro-earthquakes rather than large events. Seismic images and multibeam bathymetry from lithosphere of similar thermal thickness from different trenches display a remarkable variability of the intensity of bending-related deformation along the subduction zones where plate age does not change significantly indicating that the intensity of deformation (not the depth) and perhaps hydration is very variable in space and not controlled by plate age. Seismic images showing hundreds of kilometers perpendicular to the trench into the incoming plate show that the bending-related deformation reaches mantle under the outer rise, well before the lithosphere plunges into the trench and develops the marked bend-faulting fabric observable in bathymetric maps. Thus, alteration occurs in a hundreds-of-km wide area, with deformation intensity related to local characteristics, and deformation depth to plate age.

The influence of the charge-exchange reactions of carbon in the photoionization models for spectrum-line emitting region in the quasi-stellar objects

International Nuclear Information System (INIS)

Souza Pellegrini, P.S. de.

1976-08-01

The charge exchange reactions: C +2 + H sub(e) 0 → H +1 + C +1 and C +2 + H 0 → H +1 + C +1 were taken into account in the ionization equilibrium of Carbon in photoionization models for line emitting regions of quasi-stellar objects. The new ionization structure of Carbon was obtained and the intensities of the most important emission lines of this element usually observed in QSO's with large redshifts were calculated. The charge exchange with Hidrogen produces negligible effects while the importance of taking into account the charge exchange with Helium can be seen from the change of the ionization structure of Carbon in all considered models. The homogeneous optically thin model is shown not to be consistent with the observations. For non homogeneous optically thick models observable changes in line intensities occur when in the region where charge exhange is dominant the electron density is high enough to produce collisional excitation and consequent line emission. (Author)

Transition-Region Ultraviolet Explosive Events in IRIS Si IV: A Statistical Analysis

Science.gov (United States)

Bartz, Allison

2018-01-01

Explosive events (EEs) in the solar transition region are characterized by broad, non-Gaussian line profiles with wings at Doppler velocities exceeding the speed of sound. We present a statistical analysis of 23 IRIS (Interface Region Imaging Spectrograph) sit-and-stare observations, observed between April 2014 and March 2017. Using the IRIS Si IV 1394 Å and 1403 Å spectral windows and the 1400Å Slit Jaw images we have identified 581 EEs. We found that most EEs last less than 20 min. and have a spatial scale on the slit less than 10”, agreeing with measurements in previous work. We observed most EEs in active regions, regardless of date of observation, but selection bias of IRIS observations cannot be ruled out. We also present preliminary findings of optical depth effects from our statistical study.

Curves of growth of spectral lines emitted by a laser-induced plasma: influence of the temporal evolution and spatial inhomogeneity of the plasma

Energy Technology Data Exchange (ETDEWEB)

Aguilera, J.A.; Bengoechea, J.; Aragon, C. E-mail: carlos.aragon@unavarra.es

2003-02-03

The curves of growth (COG) of five Fe I lines emitted from a laser-induced plasma, generated with Fe-Ni alloys in air at atmospheric pressure, have been investigated. Spectral lines with different energy levels and line widths, emitted with a broad range of optical depths, have been included in the study in order to check the validity of theoretical models proposed for COG generation, based in the radiative transfer within a plasma in local thermodynamic equilibrium. The COGs have been measured at time windows of 4-5 {mu}s and 15-18 {mu}s. The Stark widths of the Fe I lines have been obtained, and the line widths have been determined by measuring the plasma electron density at the time windows selected. It is shown that at a time window of 4-5 {mu}s, the inhomogeneity of the plasma magnitudes has an important influence on the COGs of intense lines. For this time window, a two-region model of the plasma has been used to generate theoretical COGs that describe satisfactorily the experimental curves of all the lines using a single set of plasma parameters. The results reveal the existence of considerable gradients between the inner and the outer plasma regions in the temperature (9400-7800 K) and in the density of Fe atoms (4x10{sup 16}-0.02x10{sup 16} cm{sup -3} for a sample with 100% Fe). On the contrary, at the time window 15-18 {mu}s, at which the plasma has suffered most of its expansion and cooling process, the COGs of all the lines may be described by a single-region model, corresponding to a plasma with uniform temperature (6700 K) and density of Fe atoms (0.06x10{sup 16} cm{sup -3} for a sample with 100% Fe). It is also shown that at initial times, the plasma inhomogeneity has an important effect in the line profiles of intense spectral lines, which are described by using the two-region model of the laser-induced plasma.

78 FR 20119 - Broad Stakeholder Survey

Science.gov (United States)

2013-04-03

... DEPARTMENT OF HOMELAND SECURITY [Docket No. DHS-2012-0042] Broad Stakeholder Survey AGENCY... concerning the Broad Stakeholder Survey. DHS previously published this ICR in the Federal Register on August... across the Nation. The Broad Stakeholder Survey is designed to gather stakeholder feedback on the...

Broad band exciplex dye lasers

International Nuclear Information System (INIS)

Dienes, A.; Shank, C.V.; Trozzolo, A.M.

1975-01-01

The disclosure is concerned with exciplex dye lasers, i.e., lasers in which the emitting species is a complex formed only from a constituent in an electronically excited state. Noting that an exciplex laser, favorable from the standpoint of broad tunability, results from a broad shift in the peak emission wavelength for the exciplex relative to the unreacted species, a desirable class resulting in such broad shift is described. Preferred classes of laser media utilizing specified resonant molecules are set forth. (auth)

A study of the region of massive star formation L379IRS1 in radio lines of methanol and other molecules

Science.gov (United States)

Kalenskii, S. V.; Shchurov, M. A.

2016-04-01

The results of spectral observations of the region of massive star formation L379IRS1 (IRAS18265-1517) are presented. The observations were carried out with the 30-m Pico Veleta radio telescope (Spain) at seven frequencies in the 1-mm, 2-mm, and 3-mm wavelength bands. Lines of 24 molecules were detected, from simple diatomic or triatomic species to complex eight- or nine-atom compounds such as CH3OCHO or CH3OCH3. Rotation diagrams constructed from methanol andmethyl cyanide lines were used to determine the temperature of the quiescent gas in this region, which is about 40-50 K. In addition to this warm gas, there is a hot component that is revealed through high-energy lines of methanol and methyl cyanide, molecular lines arising in hot regions, and the presence of H2O masers and Class II methanol masers at 6.7 GHz, which are also related to hot gas. One of the hot regions is probably a compact hot core, which is located near the southern submillimeter peak and is related to a group of methanol masers at 6.7 GHz. High-excitation lines at other positions may be associated with other hot cores or hot post-shock gas in the lobes of bipolar outflows. The rotation diagrams can be use to determine the column densities and abundances of methanol (10-9) and methyl cyanide (about 10-11) in the quiescent gas. The column densities of A- and E-methanol in L379IRS1 are essentually the same. The column densities of other observedmolecules were calculated assuming that the ratios of the molecular level abundances correspond to a temperature of 40 K. The molecular composition of the quiescent gas is close to that in another region of massive star formation, DR21(OH). The only appreciable difference is that the column density of SO2 in L379IRS1 is at least a factor of 20 lower than the value in DR21(OH). The SO2/CS and SO2/OCS abundance ratios, which can be used as chemical clocks, are lower in L379IRS1 than in DR21(OH), suggesting that L379IRS1 is probably younger than DR21(OH).

Modelling telluric line spectra in the optical and infrared with an application to VLT/X-Shooter spectra

Science.gov (United States)

Rudolf, N.; Günther, H. M.; Schneider, P. C.; Schmitt, J. H. M. M.

2016-01-01

Context. Earth's atmosphere imprints a large number of telluric absorption and emission lines on astronomical spectra, especially in the near infrared, that need to be removed before analysing the affected wavelength regions. Aims: These lines are typically removed by comparison to A- or B-type stars used as telluric standards that themselves have strong hydrogen lines, which complicates the removal of telluric lines. We have developed a method to circumvent that problem. Methods: For our IDL software package tellrem we used a recent approach to model telluric absorption features with the line-by-line radiative transfer model (LBLRTM). The broad wavelength coverage of the X-Shooter at VLT allows us to expand their technique by determining the abundances of the most important telluric molecules H2O, O2, CO2, and CH4 from sufficiently isolated line groups. For individual observations we construct a telluric absorption model for most of the spectral range that is used to remove the telluric absorption from the object spectrum. Results: We remove telluric absorption from both continuum regions and emission lines without systematic residuals for most of the processable spectral range; however, our method increases the statistical errors. The errors of the corrected spectrum typically increase by 10% for S/N ~ 10 and by a factor of two for high-quality data (S/N ~ 100), I.e. the method is accurate on the percent level. Conclusions: Modelling telluric absorption can be an alternative to the observation of standard stars for removing telluric contamination. Based on observations collected at the European Southern Observatory, Paranal, Chile, 085.C-0764(A) and 60.A-9022(C).The tellrem package is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/585/A113

When does biodiversity matter? Assessing ecosystem services across broad regions using forest inventory and analysis data

Science.gov (United States)

Kevin M. Potter; Christopher W. Woodall; Christopher M. Oswalt; Basil V. III Iannone; Songlin Fei

2015-01-01

Biodiversity is expected to convey numerous functional benefits to forested ecosystems, including increased productivity and resilience. When assessing biodiversity, however, statistics that account for evolutionary relationships among species may be more ecologically meaningful than traditional measures such as species richness. In three broad-scale studies, we...

Broad-scale Population Genetics of the Host Sea Anemone, Heteractis magnifica

KAUST Repository

Emms, Madeleine

2015-12-01

Broad-scale population genetics can reveal population structure across an organism’s entire range, which can enable us to determine the most efficient population-wide management strategy depending on levels of connectivity. Genetic variation and differences in genetic diversity on small-scales have been reported in anemones, but nothing is known about their broad-scale population structure, including that of “host” anemone species, which are increasingly being targeted in the aquarium trade. In this study, microsatellite markers were used as a tool to determine the population structure of a sessile, host anemone species, Heteractis magnifica, across the Indo-Pacific region. In addition, two rDNA markers were used to identify Symbiodinium from the samples, and phylogenetic analyses were used to measure diversity and geographic distribution of Symbiodinium across the region. Significant population structure was identified in H. magnifica across the Indo-Pacific, with at least three genetic breaks, possibly the result of factors such as geographic distance, geographic isolation and environmental variation. Symbiodinium associations were also affected by environmental variation and supported the geographic isolation of some regions. These results suggests that management of H. magnifica must be implemented on a local scale, due to the lack of connectivity between clusters. This study also provides further evidence for the combined effects of geographic distance and environmental distance in explaining genetic variance.

Threaded-Field-Line Model for the Transition Region and Solar Corona

Science.gov (United States)

Sokolov, I.; van der Holst, B.; Gombosi, T. I.

2014-12-01

In numerical simulations of the solar corona, both for the ambient state and especially for dynamical processes the most computational resources are spent for maintaining the numerical solution in the Low Solar Corona and in the transition region, where the temperature gradients are very sharp and the magnetic field has a complicated topology. The degraded computational efficiency is caused by the need in a highest resolution as well as the use of the fully three-dimensional implicit solver for electron heat conduction. On the other hand, the physical nature of the processes involved is rather simple (which still does not facilitate the numerical methods) as long as the heat fluxes as well as slow plasma motional velocities are aligned with the magnetic field. The Alfven wave turbulence, which is often believed to be the main driver of the solar wind and the main source of the coronal heating, is characterized by the Poynting flux of the waves, which is also aligned with the magnetic field. Therefore, the plasma state in any point of the three-dimensional grid in the Low Solar Corona can be found by solving a set of one-dimensional equations for the magnetic field line ("thread"), which passes through this point and connects it to the chromosphere and to the global Solar Corona. In the present paper we describe an innovative computational technology based upon the use of the magnetic-field-line-threads to forlmulate the boundary condition for the global solar corona model which traces the connection of each boundary point to the cromosphere along the threads.

Transcription-factor occupancy at HOT regions quantitatively predicts RNA polymerase recruitment in five human cell lines.

KAUST Repository

Foley, Joseph W; Sidow, Arend

2013-01-01

BACKGROUND: High-occupancy target (HOT) regions are compact genome loci occupied by many different transcription factors (TFs). HOT regions were initially defined in invertebrate model organisms, and we here show that they are a ubiquitous feature of the human gene-regulation landscape. RESULTS: We identified HOT regions by a comprehensive analysis of ChIP-seq data from 96 DNA-associated proteins in 5 human cell lines. Most HOT regions co-localize with RNA polymerase II binding sites, but many are not near the promoters of annotated genes. At HOT promoters, TF occupancy is strongly predictive of transcription preinitiation complex recruitment and moderately predictive of initiating Pol II recruitment, but only weakly predictive of elongating Pol II and RNA transcript abundance. TF occupancy varies quantitatively within human HOT regions; we used this variation to discover novel associations between TFs. The sequence motif associated with any given TF's direct DNA binding is somewhat predictive of its empirical occupancy, but a great deal of occupancy occurs at sites without the TF's motif, implying indirect recruitment by another TF whose motif is present. CONCLUSIONS: Mammalian HOT regions are regulatory hubs that integrate the signals from diverse regulatory pathways to quantitatively tune the promoter for RNA polymerase II recruitment.

Transcription-factor occupancy at HOT regions quantitatively predicts RNA polymerase recruitment in five human cell lines.

KAUST Repository

Foley, Joseph W

2013-10-20

BACKGROUND: High-occupancy target (HOT) regions are compact genome loci occupied by many different transcription factors (TFs). HOT regions were initially defined in invertebrate model organisms, and we here show that they are a ubiquitous feature of the human gene-regulation landscape. RESULTS: We identified HOT regions by a comprehensive analysis of ChIP-seq data from 96 DNA-associated proteins in 5 human cell lines. Most HOT regions co-localize with RNA polymerase II binding sites, but many are not near the promoters of annotated genes. At HOT promoters, TF occupancy is strongly predictive of transcription preinitiation complex recruitment and moderately predictive of initiating Pol II recruitment, but only weakly predictive of elongating Pol II and RNA transcript abundance. TF occupancy varies quantitatively within human HOT regions; we used this variation to discover novel associations between TFs. The sequence motif associated with any given TF\\'s direct DNA binding is somewhat predictive of its empirical occupancy, but a great deal of occupancy occurs at sites without the TF\\'s motif, implying indirect recruitment by another TF whose motif is present. CONCLUSIONS: Mammalian HOT regions are regulatory hubs that integrate the signals from diverse regulatory pathways to quantitatively tune the promoter for RNA polymerase II recruitment.

GOSAT-2014 methane spectral line list

International Nuclear Information System (INIS)

Nikitin, A.V.; Lyulin, O.M.; Mikhailenko, S.N.; Perevalov, V.I.; Filippov, N.N.; Grigoriev, I.M.; Morino, I.; Yoshida, Y.; Matsunaga, T.

2015-01-01

The updated methane spectral line list GOSAT-2014 for the 5550–6240 cm −1 region with the intensity cutoff of 5×10 –25 cm/molecule at 296 K is presented. The line list is based on the extensive measurements of the methane spectral line parameters performed at different temperatures and pressures of methane without and with buffer gases N 2 , O 2 and air. It contains the following spectral line parameters of about 12150 transitions: line position, line intensity, energy of lower state, air-induced and self-pressure-induced broadening and shift coefficients and temperature exponent of air-broadening coefficient. The accuracy of the line positions and intensities are considerably improved in comparison with the previous version GOSAT-2009. The improvement of the line list is done mainly due to the involving to the line position and intensity retrieval of six new spectra recorded with short path way (8.75 cm). The air-broadening and air-shift coefficients for the J-manifolds of the 2ν 3 (F 2 ) band are refitted using the new more precise values of the line positions and intensities. The line assignment is considerably extended. The lower state J-value was assigned to 6397 lines representing 94.4% of integrated intensity of the considering wavenumber region. The complete assignment was done for 2750 lines. - Highlights: • The upgrade of the GOSAT methane line list in the 5550–6240 cm −1 region is done. • 12,146 experimental methane line positions and intensities are retrieved. • 6376 lower energy levels for methane lines are determined

Molecular line study of massive star-forming regions from the Red MSX Source survey

Science.gov (United States)

Yu, Naiping; Wang, Jun-Jie

2014-05-01

In this paper, we have selected a sample of massive star-forming regions from the Red MSX Source survey, in order to study star formation activities (mainly outflow and inflow signatures). We have focused on three molecular lines from the Millimeter Astronomy Legacy Team Survey at 90 GHz: HCO+(1-0), H13CO+(1-0) and SiO(2-1). According to previous observations, our sources can be divided into two groups: nine massive young stellar object candidates (radio-quiet) and 10 H II regions (which have spherical or unresolved radio emissions). Outflow activities have been found in 11 sources, while only three show inflow signatures in all. The high outflow detection rate means that outflows are common in massive star-forming regions. The inflow detection rate was relatively low. We suggest that this was because of the beam dilution of the telescope. All three inflow candidates have outflow(s). The outward radiation and thermal pressure from the central massive star(s) do not seem to be strong enough to halt accretion in G345.0034-00.2240. Our simple model of G318.9480-00.1969 shows that it has an infall velocity of about 1.8 km s-1. The spectral energy distribution analysis agrees our sources are massive and intermediate-massive star formation regions.

Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

Energy Technology Data Exchange (ETDEWEB)

Kubota-Koketsu, Ritsuko; Mizuta, Hiroyuki [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan); Oshita, Masatoshi; Ideno, Shoji [Osaka Research Laboratory, Benesis Corporation, Yodogawa-ku, Osaka 532-6505 (Japan); Yunoki, Mikihiro [Osaka Research Laboratory, Benesis Corporation, Yodogawa-ku, Osaka 532-6505 (Japan); Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan); Kuhara, Motoki [Ina Laboratory, Medical and Biological Laboratories Corporation, Ltd., Ina, Nagano 396-0002 (Japan); Yamamoto, Naomasa [Department of Biochemistry, School of Pharmaceutical Sciences, Ohu University, Koriyama, Fukushima 963-8611 (Japan); Okuno, Yoshinobu [Kanonji Institute, The Research Foundation for Microbial Diseases of Osaka University, Kanonji, Kagawa 768-0061 (Japan); Ikuta, Kazuyoshi, E-mail: ikuta@biken.osaka-u.ac.jp [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan)

2009-09-11

Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizing ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.

Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

International Nuclear Information System (INIS)

Kubota-Koketsu, Ritsuko; Mizuta, Hiroyuki; Oshita, Masatoshi; Ideno, Shoji; Yunoki, Mikihiro; Kuhara, Motoki; Yamamoto, Naomasa; Okuno, Yoshinobu; Ikuta, Kazuyoshi

2009-01-01

Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizing ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.

CH+(1-0) and 13CH+(1-0) absorption lines in the direction of massive star-forming regions

NARCIS (Netherlands)

Falgarone, E.; Godard, B.; Cernicharo, J.; de Luca, M.; Gerin, M.; Phillips, T. G.; Black, J. H.; Lis, D. C.; Bell, T. A.; Boulanger, F.; Coutens, A.; Dartois, E.; Encrenaz, P.; Giesen, T.; Goicoechea, J. R.; Goldsmith, P. F.; Gupta, H.; Gry, C.; Hennebelle, P.; Herbst, E.; Hily-Blant, P.; Joblin, C.; Kaźmierczak, M.; Kołos, R.; Krełowski, J.; Martin-Pintado, J.; Monje, R.; Mookerjea, B.; Neufeld, D. A.; Perault, M.; Pearson, J. C.; Persson, C.; Plume, R.; Salez, M.; Schmidt, M.; Sonnentrucker, P.; Stutzki, J.; Teyssier, D.; Vastel, C.; Yu, S.; Menten, K.; Geballe, T. R.; Schlemmer, S.; Shipman, R.; Tielens, A. G. G. M.; Philipp, S.; Cros, A.; Zmuidzinas, J.; Samoska, L. A.; Klein, K.; Lorenzani, A.; Szczerba, R.; Péron, I.; Cais, P.; Gaufre, P.; Ravera, L.; Morris, P.; Lord, S.; Planesas, P.

2010-01-01

We report the detection of the ground-state rotational transition of the methylidyne cation CH+ and its isotopologue 13CH+ toward the remote massive star-forming regions W33A, W49N, and W51 with the HIFI instrument onboard the Herschel satellite. Both lines are seen only in absorption against the

A catapult model for the narrow-line region in Seyferts and radio galaxies

International Nuclear Information System (INIS)

Smith, M.D.

1984-01-01

The kinematics and stability of clouds falling radially into a supersonic wind are studied. A critical parameter is found, the ejection coefficient, which separates clouds which continue to gravitate inwards from those which are catapulted out by the ram pressure of the wind. This leads to a maximum size for ejected clouds. The clouds are partially broken up by fluid dynamic instabilities and the fragments expelled with enhanced velocities. This model is applied to the narrow-line region of Seyferts and radio galaxies. A quasi-steady picture may be established for the wind-ambient medium interaction zone. The wind is shocked and escapes through jets or bubbles; the ambient medium cools, forming the clouds which gravitate inwards. (author)

Extended and broad Ly α emission around a BAL quasar at z ˜ 5

Science.gov (United States)

Ginolfi, M.; Maiolino, R.; Carniani, S.; Arrigoni Battaia, F.; Cantalupo, S.; Schneider, R.

2018-05-01

In this work we report deep MUSE observations of a broad absorption line (BAL) quasar at z ˜ 5, revealing a Ly α nebula with a maximum projected linear size of ˜60 kpc around the quasar (down to our 2σ SB limit per layer of ˜ 9× 10^{-19} erg s^{-1} cm^{-2} arcsec^{-2} for a 1 arcsec2 aperture). After correcting for the cosmological surface brightness dimming, we find that our nebula, at z ˜ 5, has an intrinsically less extended Ly α emission than nebulae at lower redshift. However, such a discrepancy is greatly reduced when referring to comoving distances, which take into account the cosmological growth of dark matter (DM) haloes, suggesting a positive correlation between the size of Ly α nebulae and the sizes of DM haloes/structures around quasars. Differently from the typical nebulae around radio-quiet non-BAL quasars, in the inner regions (˜10 kpc) of the circumgalactic medium of our source, the velocity dispersion of the Ly α emission is very high (FWHM > 1000 km s-1), suggesting that in our case we may be probing outflowing material associated with the quasar.

Water in star-forming regions with Herschel (WISH) : IV. A survey of low-J H2O line profiles toward high-mass protostars

NARCIS (Netherlands)

van der Tak, F. F. S.; Chavarria, L.; Herpin, F.; Wyrowski, F.; Walmsley, C. M.; van Dishoeck, E. F.; Benz, A. O.; Bergin, E. A.; Caselli, P.; Hogerheijde, M. R.; Johnstone, D.; Kristensen, L. E.; Liseau, R.; Nisini, B.; Tafalla, M.

Context. Water is a key constituent of star-forming matter, but the origin of its line emission and absorption during high-mass star formation is not well understood. Aims. We study the velocity profiles of low-excitation H2O lines toward 19 high-mass star-forming regions and search for trends with

Modification of the U-line of the RHIC injection line

International Nuclear Information System (INIS)

Xu, Jianming.

1991-09-01

The parameters of the U-line of the RHIC injection line with low β waist are described. In that lattice, the location of SA is not dispersion free and 14 quadrupoles are needed. This line has been modified to move SA to a dispersion free region (after the 8-degree bend), the length and maximum gradient of quadrupoles have been adjusted to fit the existing quadrupole parameters and the number of quadrupoles is reduced to 12. 2 refs., 3 tabs

Herschel/HIFI observations of high-J CO lines in the NGC 1333 low-mass star-forming region

DEFF Research Database (Denmark)

Yildiz, U. A.; van Dishoeck, E. F.; Kristensen, L. E.

2010-01-01

Herschel/HIFI observations of high-J lines (up to Ju = 10) of 12CO, 13CO and C18O are presented toward three deeply embedded low-mass protostars, NGC 1333 IRAS 2A, IRAS 4A, and IRAS 4B, obtained as part of the Water In Star-forming regions with Herschel (WISH) key program. The spectrally-resolved......Herschel/HIFI observations of high-J lines (up to Ju = 10) of 12CO, 13CO and C18O are presented toward three deeply embedded low-mass protostars, NGC 1333 IRAS 2A, IRAS 4A, and IRAS 4B, obtained as part of the Water In Star-forming regions with Herschel (WISH) key program. The spectrally....... Their intensities require a jump in the CO abundance at an evaporation temperature around 25 K, thus providing new direct evidence for a CO ice evaporation zone around low-mass protostars. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia...... and with important participation from NASA.Appendices and acknowledgements (pages 5 to 7) are only available in electronic form at http://www.aanda.org...

Sound Transmission in a Duct with Sudden Area Expansion, Extended Inlet, and Lined Walls in Overlapping Region

Directory of Open Access Journals (Sweden)

Ahmet Demir

2016-01-01

Full Text Available The transmission of sound in a duct with sudden area expansion and extended inlet is investigated in the case where the walls of the duct lie in the finite overlapping region lined with acoustically absorbent materials. By using the series expansion in the overlap region and using the Fourier transform technique elsewhere we obtain a Wiener-Hopf equation whose solution involves a set of infinitely many unknown expansion coefficients satisfying a system of linear algebraic equations. Numerical solution of this system is obtained for various values of the problem parameters, whereby the effects of these parameters on the sound transmission are studied.

Infrared studies of galactic nebulae. IV - Continuum and line radiation from planetary nebulae.

Science.gov (United States)

Gillett, F. C.; Merrill, K. M.; Stein, W. A.

1972-01-01

Observations are reported of the detection of IR radiation from several planetary nebulae not previously known to be radiating at these wavelengths. Broad spectral bandwidth observations indicate that ir radiation in excess of that expected from atomic processes is a common phenomenon among these objects. Investigations with narrow spectral bandwidth show that in a few cases the energy in the 10.52-micron line is a significant fraction of the total energy observed in the broad-band measurements and in other cases a relatively small fraction of the total radiation. Other observations on two sources with narrow spectral bandwidth adjacent to the 10.52-micron line indicate that at these wavelengths a true continuum of radiation exists as well as lines. The results are discussed in relation to visual and radio-wavelength data.

Continuous wave power scaling in high power broad area quantum cascade lasers

Science.gov (United States)

Suttinger, M.; Leshin, J.; Go, R.; Figueiredo, P.; Shu, H.; Lyakh, A.

2018-02-01

Experimental and model results for high power broad area quantum cascade lasers are presented. Continuous wave power scaling from 1.62 W to 2.34 W has been experimentally demonstrated for 3.15 mm-long, high reflection-coated 5.6 μm quantum cascade lasers with 15 stage active region for active region width increased from 10 μm to 20 μm. A semi-empirical model for broad area devices operating in continuous wave mode is presented. The model uses measured pulsed transparency current, injection efficiency, waveguide losses, and differential gain as input parameters. It also takes into account active region self-heating and sub-linearity of pulsed power vs current laser characteristic. The model predicts that an 11% improvement in maximum CW power and increased wall plug efficiency can be achieved from 3.15 mm x 25 μm devices with 21 stages of the same design but half doping in the active region. For a 16-stage design with a reduced stage thickness of 300Å, pulsed roll-over current density of 6 kA/cm2 , and InGaAs waveguide layers; optical power increase of 41% is projected. Finally, the model projects that power level can be increased to 4.5 W from 3.15 mm × 31 μm devices with the baseline configuration with T0 increased from 140 K for the present design to 250 K.

Efficient Banknote Recognition Based on Selection of Discriminative Regions with One-Dimensional Visible-Light Line Sensor.

Science.gov (United States)

Pham, Tuyen Danh; Park, Young Ho; Kwon, Seung Yong; Park, Kang Ryoung; Jeong, Dae Sik; Yoon, Sungsoo

2016-03-04

Banknote papers are automatically recognized and classified in various machines, such as vending machines, automatic teller machines (ATM), and banknote-counting machines. Previous studies on automatic classification of banknotes have been based on the optical characteristics of banknote papers. On each banknote image, there are regions more distinguishable than others in terms of banknote types, sides, and directions. However, there has been little previous research on banknote recognition that has addressed the selection of distinguishable areas. To overcome this problem, we propose a method for recognizing banknotes by selecting more discriminative regions based on similarity mapping, using images captured by a one-dimensional visible light line sensor. Experimental results with various types of banknote databases show that our proposed method outperforms previous methods.

Efficient Banknote Recognition Based on Selection of Discriminative Regions with One-Dimensional Visible-Light Line Sensor

Directory of Open Access Journals (Sweden)

Tuyen Danh Pham

2016-03-01

Full Text Available Banknote papers are automatically recognized and classified in various machines, such as vending machines, automatic teller machines (ATM, and banknote-counting machines. Previous studies on automatic classification of banknotes have been based on the optical characteristics of banknote papers. On each banknote image, there are regions more distinguishable than others in terms of banknote types, sides, and directions. However, there has been little previous research on banknote recognition that has addressed the selection of distinguishable areas. To overcome this problem, we propose a method for recognizing banknotes by selecting more discriminative regions based on similarity mapping, using images captured by a one-dimensional visible light line sensor. Experimental results with various types of banknote databases show that our proposed method outperforms previous methods.

Lifetime broadening of atomic lines produced upon ultrafast dissociation of HCl and HBr

Energy Technology Data Exchange (ETDEWEB)

Lablanquie, P., E-mail: pascal.lablanquie@upmc.fr [Sorbonne Universités, UPMC Univ Paris 06, LCPMR, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); CNRS, LCPMR (UMR 7614), 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Iwayama, H. [UVSOR Facility, Institute for Molecular Science, Okazaki 444-8585 (Japan); Penent, F. [Sorbonne Universités, UPMC Univ Paris 06, LCPMR, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); CNRS, LCPMR (UMR 7614), 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Soejima, K. [Department of Environmental Science, Niigata University, Niigata 950-2181 (Japan); Shigemasa, E. [UVSOR Facility, Institute for Molecular Science, Okazaki 444-8585 (Japan)

2014-08-15

Highlights: • Ultrafast dissociation of HCl is triggered by 2p{sub 3/2} → σ* excitation. • Ultrafast dissociation of HBr is triggered by 3d{sub 5/2} → σ* excitation. • Photoelectron spectroscopy reveals sharp vibrational molecular lines and broad atomic lines. • The profiles of the atomic lines are analyzed in detail. • We extract the lifetime of the inner shell hole in the neutral atomic fragment. - Abstract: Ultrafast dissociation of the HCl and HBr molecules excited respectively to the 2p{sub 3/2} → σ* and 3d{sub 5/2} → σ* resonances are studied with high resolution photoelectron spectroscopy. Sharp vibrational molecular lines and broad atomic lines are observed. The analysis of the profile of the atomic lines gives access to the lifetimes of the inner shell 2p{sub 3/2} hole in the Cl* (2p{sub 3/2}){sup −1} 3s{sup 2}3p{sup 6} configuration, and the inner shell 3d{sub 5/2} hole in the Br* (3d{sub 5/2}){sup −1} 4s{sup 2}4p{sup 6} configuration.

High resolution study of MSiH4 (M=28, 29, 30) in the Dyad Region: Analysis of line positions, intensities and half-widths

Science.gov (United States)

Ulenikov, O. N.; Gromova, O. V.; Bekhtereva, E. S.; Raspopova, N. I.; Kashirina, N. V.; Fomchenko, A. L.; Sydow, C.; Bauerecker, S.

2017-12-01

The infrared spectra of SiH4 in natural abundance (92.23% of 28SiH4, 4.68% of 29SiH4, and 3.09% of 30SiH4) were measured in the region of 600-1200 cm-1 with a Bruker IFS 120HR Fourier transform spectrometer, analyzed and compared with the results available in the literature. More than 3500 transitions with Jmax. = 27 were assigned to the dyad bands ν4 and ν2 of 28SiH4 (the band ν2 is allowed in Raman, but forbidden in absorption spectra for symmetry reasons, and its transitions appear in absorption spectra only because of strong Coriolis interaction with the ν4 band). Rotational, centrifugal distortion, tetrahedral splitting, and interaction parameters for the ground, (0100) and (0001) vibrational states were determined from the fit of experimental line positions. The obtained set of parameters reproduces the initial experimental data with accuracy close to experimental uncertainties. The results of the analogous analyses of the 29SiH4 and 30SiH4 isotopologues are also presented (the numbers of the assigned transitions are here more than 1360 and 1120). An further analysis of about 790 experimental ro-vibrational lines in the dyad region of 28SiH4 was performed using the Voigt profile to simulate the measured line shape and to determine experimental line intensities. A set of 4 effective dipole moment parameters for the dyad of 28SiH4 was obtained on that basis from the weighted fit, which reproduce the initial experimental intensities of about 790 lines with the drms = 5.6 % . Analogous analyses were made for the two other isotopic species, 29SiH4, and 30SiH4. A detailed line list of transitions in the region of 750-1150 cm-1 is generated. The half-widths of 40 ro-vibrational lines (Jup.max. = 16) are studied from the multi-spectrum analysis, and self-pressure broadening coefficients are determined.

Temperature diagnostic line ratios of Fe XVII

International Nuclear Information System (INIS)

Raymond, J.C.; Smith, B.W.; Los Alamos National Lab., NM)

1986-01-01

Based on extensive calculations of the excitation rates of Fe XVII, four temperature-sensitive line ratios are investigated, paying special attention to the contribution of resonances to the excitation rates and to the contributions of dielectronic recombination satellites to the observed line intensities. The predictions are compared to FPCS observations of Puppis A and to Solar Maximum Mission (SMM) and SOLEX observations of the sun. Temperature-sensitive line ratios are also computed for emitting gas covering a broad temperature range. It is found that each ratio yields a differently weighted average for the temperature and that this accounts for some apparent discrepancies between the theoretical ratios and solar observations. The effects of this weighting on the Fe XVII temperature diagnostics and on the analogous Fe XXIV/Fe XXV satellite line temperature diagnostics are discussed. 27 references

Distribution patterns of the subtropical evergreen broad-leaved forests of southwestern China, as compared with those of the eastern Chinese subtropical regions

Directory of Open Access Journals (Sweden)

Tang, C. Q.

2015-12-01

Full Text Available This paper analyzes the geographic distribution patterns of the subtropical evergreen broad-leaved forests of southwestern China, and compares with other subtropical regions in the east of China in terms of forest types, pertinent species, and spatial distribution along latitudinal, longitudinal and altitudinal gradients. In general, for both the western and the eastern subtropical regions, the evergreen broad-leaved forests are dominated by species of Castanopsis, Lithocarpus, Cyclobalanopsis (Fagaceae, Machilus, Cinnamomum (Lauraceae, Schima (Theaceae, Manglietia, and Michelia, (Magnoliaceae, while in southwestern China there are more diverse forest types including semi-humid, monsoon, mid-montane moist and humid evergreen broad-leaved forests, but only monsoon and humid forests in the east. The Yunnan area has more varied species of Lithocarpus or Cyclobalanopsis or Castanopsis as dominants than does eastern China, where the chief dominant genus is Castanopsis. The upper limits of the evergreen broad-leaved forests are mainly 2400–2800 m in western Yunnan and western Sichuan, much higher than in eastern China (600–1500, but 2500 m in Taiwan. Also discussed are the environmental effects on plant diversity of the evergreen broad-leaved forest ecosystems exemplified by Yunnan and Taiwan.En este trabajo se analiza los patrones de distribución geográfica de los bosques subtropicales perennifolios de hoja ancha del suroeste de china, y se comparan con los de otras regiones subtropicales del este de China en términos de tipología de bosque, especies relevantes, y distribución espacial a lo largo de un gradiente latitudinal, longitudinal y altitudinal. De manera general, los bosques perennifolios de hoja ancha de la regiones subtropicales tanto orientales como occidentales presentan dominancia de especies de Castanopsis, Lithocarpus, Cyclobalanopsis (Fagaceae, Machilus, Cinnamomum (Lauraceae, Schima (Theaceae, Manglietia y Michelia

Naturally occurring broad-spectrum powdery mildw resistance in a central American tomato accession is caused by loss of Mlo function

NARCIS (Netherlands)

Bai, Y.; Pavan, S.N.C.; Zheng, Z.; Zappel, N.F.; Reinstadler, A.; Lotti, C.; Giovanni, de C.; Ricciardi, L.; Lindhout, P.; Visser, R.G.F.; Theres, K.; Panstruga, R.

2008-01-01

The resistant cherry tomato (Solanum lycopersicum var. cerasiforme) line LC-95, derived from an accession collected in Ecuador, harbors a natural allele (ol-2) that confers broad-spectrum and recessively inherited resistance to powdery mildew (Oidium neolycopersici). As both the genetic and

The viral envelope is not sufficient to transfer the unique broad cell tropism of Bungowannah virus to a related pestivirus.

Science.gov (United States)

Richter, Maria; Reimann, Ilona; Schirrmeier, Horst; Kirkland, Peter D; Beer, Martin

2014-10-01

Bungowannah virus is the most divergent pestivirus, and both origin and reservoir host have not been identified so far. We therefore performed in vitro tropism studies, which showed that Bungowannah virus differs remarkably from other pestiviruses. Interestingly, cell lines of vervet monkey, mouse, human and even of bat origin were susceptible. This broad in vitro tropism was not observed for a chimeric bovine viral diarrhoea virus (BVDV) expressing all structural proteins of Bungowannah virus. The viral envelope was not sufficient to completely transfer the cell tropism of Bungowannah virus to another pestivirus, and viral RNA replication was either markedly reduced or not detectable in a number of different cell lines for the tested BVDV strain and the chimera. We therefore suggest that the replication machinery together with the viral envelope is responsible for the unique broad cell tropism of Bungowannah virus. © 2014 The Authors.

Probing the Physics of Narrow-line Regions in Active Galaxies. IV. Full Data Release of the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7)

Energy Technology Data Exchange (ETDEWEB)

Thomas, Adam D.; Dopita, Michael A.; Davies, Rebecca; Hampton, Elise; Kewley, Lisa; Banfield, Julie; Groves, Brent; Sutherland, Ralph [RSAA, Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia); Shastri, Prajval; Sairam, Lalitha [Indian Institute of Astrophysics, Sarjapur Road, Bengaluru 560034 (India); James, Bethan L. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Jin, Chichuan [Max-Planck-Institut für Extraterrestrische Physik, Garching (Germany); Juneau, Stéphanie [CEA-Saclay, DSM/IRFU/SAp, F-91191 Gif-sur-Yvette (France); Kharb, Preeti [National Centre for Radio Astrophysics—Tata Institute of Fundamental Research, Pune University Campus, Post Bag 3, Ganeshkhind Pune 411007 (India); Scharwächter, Julia [Gemini Observatory, Northern Operations Center, 670 N. A’ohoku Place, Hilo, Hawaii 96720 (United States); Shalima, P. [Regional Institute of Education, Manasagangotri, Mysore 570006 (India); Sundar, M. N. [Jain University, 3rd Block Jayanagar, Bengaluru 560011 (India); Zaw, Ingyin, E-mail: adam.thomas@anu.edu.au [New York University (Abu Dhabi), 70 Washington Sq. S, New York, NY 10012 (United States)

2017-09-01

We present the second and final data release of the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). Data are presented for 63 new galaxies not included in the first data release, and we provide 2D emission-line fitting products for the full S7 sample of 131 galaxies. The S7 uses the WiFeS instrument on the ANU 2.3 m telescope to obtain spectra with a spectral resolution of R  = 7000 in the red (540–700 nm) and R  = 3000 in the blue (350–570 nm), over an integral field of 25 × 38 arcsec{sup 2} with 1 × 1 arcsec{sup 2} spatial pixels. The S7 contains both the largest sample of active galaxies and the highest spectral resolution of any comparable integral field survey to date. The emission-line fitting products include line fluxes, velocities, and velocity dispersions across the WiFeS field of view, and an artificial neural network has been used to determine the optimal number of Gaussian kinematic components for emission-lines in each spaxel. Broad Balmer lines are subtracted from the spectra of nuclear spatial pixels in Seyfert 1 galaxies before fitting the narrow lines. We bin nuclear spectra and measure reddening-corrected nuclear fluxes of strong narrow lines for each galaxy. The nuclear spectra are classified on optical diagnostic diagrams, where the strength of the coronal line [Fe vii] λ 6087 is shown to be correlated with [O iii]/H β . Maps revealing gas excitation and kinematics are included for the entire sample, and we provide notes on the newly observed objects.

THE GREEN BANK TELESCOPE H II REGION DISCOVERY SURVEY. IV. HELIUM AND CARBON RECOMBINATION LINES

Energy Technology Data Exchange (ETDEWEB)

Wenger, Trey V.; Bania, T. M. [Astronomy Department, 725 Commonwealth Avenue, Boston University, Boston, MA 02215 (United States); Balser, Dana S. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA, 22903-2475 (United States); Anderson, L. D. [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States)

2013-02-10

The Green Bank Telescope H II Region Discovery Survey (GBT HRDS) found hundreds of previously unknown Galactic regions of massive star formation by detecting hydrogen radio recombination line (RRL) emission from candidate H II region targets. Since the HRDS nebulae lie at large distances from the Sun, they are located in previously unprobed zones of the Galactic disk. Here, we derive the properties of helium and carbon RRL emission from HRDS nebulae. Our target sample is the subset of the HRDS that has visible helium or carbon RRLs. This criterion gives a total of 84 velocity components (14% of the HRDS) with helium emission and 52 (9%) with carbon emission. For our highest quality sources, the average {sup 4}He{sup +}/H{sup +} abundance ratio by number, (y {sup +}), is 0.068 {+-} 0.023(1{sigma}). This is the same ratio as that measured for the sample of previously known Galactic H II regions. Nebulae without detected helium emission give robust y {sup +} upper limits. There are 5 RRL emission components with y {sup +} less than 0.04 and another 12 with upper limits below this value. These H II regions must have either a very low {sup 4}He abundance or contain a significant amount of neutral helium. The HRDS has 20 nebulae with carbon RRL emission but no helium emission at its sensitivity level. There is no correlation between the carbon RRL parameters and the 8 {mu}m mid-infrared morphology of these nebulae.

THE AKARI 2.5-5.0 μm SPECTRAL ATLAS OF TYPE-1 ACTIVE GALACTIC NUCLEI: BLACK HOLE MASS ESTIMATOR, LINE RATIO, AND HOT DUST TEMPERATURE

Energy Technology Data Exchange (ETDEWEB)

Kim, Dohyeong; Im, Myungshin; Kim, Ji Hoon; Jun, Hyunsung David; Lee, Seong-Kook [Center for the Exploration of the Origin of the Universe (CEOU), Astronomy Program, Department of Physics and Astronomy, Seoul National University, Shillim-Dong, Kwanak-Gu, Seoul 151-742 (Korea, Republic of); Woo, Jong-Hak; Lee, Hyung Mok; Lee, Myung Gyoon [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Shillim-Dong, Kwanak-Gu, Seoul 151-742 (Korea, Republic of); Nakagawa, Takao; Matsuhara, Hideo; Wada, Takehiko; Takagi, Toshinobu [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa 252-5210 (Japan); Oyabu, Shinki [Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan); Ohyama, Youichi, E-mail: dohyeong@astro.snu.ac.kr, E-mail: mim@astro.snu.ac.kr [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan (China)

2015-01-01

We present 2.5-5.0 μm spectra of 83 nearby (0.002 < z < 0.48) and bright (K < 14 mag) type-1 active galactic nuclei (AGNs) taken with the Infrared Camera on board AKARI. The 2.5-5.0 μm spectral region contains emission lines such as Brβ (2.63 μm), Brα (4.05 μm), and polycyclic aromatic hydrocarbons (3.3 μm), which can be used for studying the black hole (BH) masses and star formation activity in the host galaxies of AGNs. The spectral region also suffers less dust extinction than in the ultra violet (UV) or optical wavelengths, which may provide an unobscured view of dusty AGNs. Our sample is selected from bright quasar surveys of Palomar-Green and SNUQSO, and AGNs with reverberation-mapped BH masses from Peterson et al. Using 11 AGNs with reliable detection of Brackett lines, we derive the Brackett-line-based BH mass estimators. We also find that the observed Brackett line ratios can be explained with the commonly adopted physical conditions of the broad line region. Moreover, we fit the hot and warm dust components of the dust torus by adding photometric data of SDSS, 2MASS, WISE, and ISO to the AKARI spectra, finding hot and warm dust temperatures of ∼1100 K and ∼220 K, respectively, rather than the commonly cited hot dust temperature of 1500 K.

Weak Hard X-Ray Emission from Two Broad Absorption Line Quasars Observed with NuStar: Compton-Thick Absorption or Intrinsic X-Ray Weakness?

Science.gov (United States)

Luo, B.; Brandt, W. N.; Alexander, D. M.; Harrison, F. A.; Stern, D.; Bauer, F. E.; Boggs, S. E.; Christensen, F. E.; Comastri, A.; Craig, W. W..;

WEAK HARD X-RAY EMISSION FROM TWO BROAD ABSORPTION LINE QUASARS OBSERVED WITH NuSTAR: COMPTON-THICK ABSORPTION OR INTRINSIC X-RAY WEAKNESS?

Energy Technology Data Exchange (ETDEWEB)

Luo, B.; Brandt, W. N. [Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Alexander, D. M.; Hickox, R. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Harrison, F. A.; Fuerst, F.; Grefenstette, B. W.; Madsen, K. K. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Bauer, F. E. [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile); Boggs, S. E.; Craig, W. W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Christensen, F. E. [DTU Space-National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Comastri, A. [INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Fabian, A. C. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Farrah, D. [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States); Fiore, F. [Osservatorio Astronomico di Roma, via Frascati 33, I-00040 Monteporzio Catone (Italy); Hailey, C. J. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Matt, G. [Dipartimento di Matematica e Fisica, Universita degli Studi Roma Tre, via della Vasca Navale 84, I-00146 Roma (Italy); Ogle, P. [IPAC, California Institute of Technology, Mail Code 220-6, Pasadena, CA 91125 (United States); and others

2013-08-01

We present Nuclear Spectroscopic Telescope Array (NuSTAR) hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray weak, probably due to absorption by the shielding gas between the nucleus and the accretion-disk wind. The two targets are among the optically brightest BAL quasars, yet they are known to be significantly X-ray weak at rest-frame 2-10 keV (16-120 times fainter than typical quasars). We would expect to obtain Almost-Equal-To 400-600 hard X-ray ({approx}> 10 keV) photons with NuSTAR, provided that these photons are not significantly absorbed (N{sub H} {approx}< 10{sup 24} cm{sup -2}). However, both BAL quasars are only detected in the softer NuSTAR bands (e.g., 4-20 keV) but not in its harder bands (e.g., 20-30 keV), suggesting that either the shielding gas is highly Compton-thick or the two targets are intrinsically X-ray weak. We constrain the column densities for both to be N{sub H} Almost-Equal-To 7 Multiplication-Sign 10{sup 24} cm{sup -2} if the weak hard X-ray emission is caused by obscuration from the shielding gas. We discuss a few possibilities for how PG 1004+130 could have Compton-thick shielding gas without strong Fe K{alpha} line emission; dilution from jet-linked X-ray emission is one likely explanation. We also discuss the intrinsic X-ray weakness scenario based on a coronal-quenching model relevant to the shielding gas and disk wind of BAL quasars. Motivated by our NuSTAR results, we perform a Chandra stacking analysis with the Large Bright Quasar Survey BAL quasar sample and place statistical constraints upon the fraction of intrinsically X-ray weak BAL quasars; this fraction is likely 17%-40%.

Doppler-shifted neutral beam line shape and beam transmission

International Nuclear Information System (INIS)

Kamperschroer, J.H.; Grisham, L.R.; Kokatnur, N.; Lagin, L.J.; Newman, R.A.; O'Connor, T.E.; Stevenson, T.N.; von Halle, A.

1994-04-01

Analysis of Doppler-shifted Balmer-α line emission from the TFTR neutral beam injection systems has revealed that the line shape is well approximated by the sum of two Gaussians, or, alternatively, by a Lorentzian. For the sum of two Gaussians, the broad portion of the distribution contains 40% of the beam power and has a divergence five times that of the narrow part. Assuming a narrow 1/e- divergence of 1.3 degrees (based on fits to the beam shape on the calorimeter), the broad part has a divergence of 6.9 degrees. The entire line shape is also well approximated by a Lorentzian with a half-maximum divergence of 0.9 degrees. Up to now, fusion neutral beam modelers have assumed a single Gaussian velocity distribution, at the extraction plane, in each direction perpendicular to beam propagation. This predicts a beam transmission efficiency from the ion source to the calorimeter of 97%. Waterflow calorimetry data, however, yield a transmission efficiency of ∼75%, a value in rough agreement with predictions of the Gaussian or Lorentzian models presented here. The broad wing of the two Gaussian distribution also accurately predicts the loss in the neutralizer. An average angle of incidence for beam loss at the exit of the neutralizer is 2.2 degrees, rather than the 4.95 degrees subtended by the center of the ion source. This average angle of incidence, which is used in computing power densities on collimators, is shown to be a function of beam divergence

CONSTRAINTS ON BLACK HOLE GROWTH, QUASAR LIFETIMES, AND EDDINGTON RATIO DISTRIBUTIONS FROM THE SDSS BROAD-LINE QUASAR BLACK HOLE MASS FUNCTION

International Nuclear Information System (INIS)

Kelly, Brandon C.; Hernquist, Lars; Siemiginowska, Aneta; Vestergaard, Marianne; Fan Xiaohui; Hopkins, Philip

2010-01-01

We present an estimate of the black hole mass function of broad-line quasars (BLQSOs) that self-consistently corrects for incompleteness and the statistical uncertainty in the mass estimates, based on a sample of 9886 quasars at 1 1 it is highly incomplete at M BH ∼ 9 M sun and L/L Edd ∼ BL > 150 ± 15 Myr for black holes at z = 1 with a mass of M BH = 10 9 M sun , and we constrain the maximum mass of a black hole in a BLQSO to be ∼3 x 10 10 M sun . Our estimated distribution of BLQSO Eddington ratios peaks at L/L Edd ∼ 0.05 and has a dispersion of ∼0.4 dex, implying that most BLQSOs are not radiating at or near the Eddington limit; however, the location of the peak is subject to considerable uncertainty. The steep increase in number density of BLQSOs toward lower Eddington ratios is expected if the BLQSO accretion rate monotonically decays with time. Furthermore, our estimated lifetime and Eddington ratio distributions imply that the majority of the most massive black holes spend a significant amount of time growing in an earlier obscured phase, a conclusion which is independent of the unknown obscured fraction. These results are consistent with models for self-regulated black hole growth, at least for massive systems at z > 1, where the BLQSO phase occurs at the end of a fueling event when black hole feedback unbinds the accreting gas, halting the accretion flow.

Doppler shift measurement of Balmer-alpha line spectrum emission from a plasma in a negative hydrogen ion source

Energy Technology Data Exchange (ETDEWEB)

Wada, M., E-mail: mwada@mail.doshisha.ac.jp; Doi, K. [Graduate School of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 Japan (Japan); Kisaki, M.; Nakano, H.; Tsumori, K. [National Institute for Fusion Science, Toki, Gifu (Japan); Nishiura, M. [Graduate School of Frontier Sciences, The Universtiy of Tokyo, Chiba 277-8561 (Japan)

2015-04-08

Balmer-α light emission from the extraction region of the LHD one-third ion source has shown a characteristic Doppler broadening in the wavelength spectrum detected by a high resolution spectrometer. The spectrum resembles Gaussian distribution near the wavelength of the intensity peak, while it has an additional component of a broader foot. The measured broadening near the wavelength of the intensity peak corresponds to 0.6 eV hydrogen atom temperature. The spectrum exhibits a larger expansion in the blue wing which becomes smaller when the line of sight is tilted toward the driver region from the original observation axis parallel to the plasma grid. A surface collision simulation model predicts the possibility of hydrogen reflection at the plasma grid surface to form a broad Balmer-α light emission spectrum.

Doppler shift measurement of Balmer-alpha line spectrum emission from a plasma in a negative hydrogen ion source

International Nuclear Information System (INIS)

Wada, M.; Doi, K.; Kisaki, M.; Nakano, H.; Tsumori, K.; Nishiura, M.

2015-01-01

Balmer-α light emission from the extraction region of the LHD one-third ion source has shown a characteristic Doppler broadening in the wavelength spectrum detected by a high resolution spectrometer. The spectrum resembles Gaussian distribution near the wavelength of the intensity peak, while it has an additional component of a broader foot. The measured broadening near the wavelength of the intensity peak corresponds to 0.6 eV hydrogen atom temperature. The spectrum exhibits a larger expansion in the blue wing which becomes smaller when the line of sight is tilted toward the driver region from the original observation axis parallel to the plasma grid. A surface collision simulation model predicts the possibility of hydrogen reflection at the plasma grid surface to form a broad Balmer-α light emission spectrum

Human broadly neutralizing antibodies to the envelope glycoprotein complex of hepatitis C virus

DEFF Research Database (Denmark)

Giang, Erick; Dorner, Marcus; Prentoe, Jannick C

2012-01-01

, and an effective vaccine should target conserved T- and B-cell epitopes of the virus. Conserved B-cell epitopes overlapping the CD81 receptor-binding site (CD81bs) on the E2 viral envelope glycoprotein have been reported previously and provide promising vaccine targets. In this study, we isolated 73 human m......Abs recognizing five distinct antigenic regions on the virus envelope glycoprotein complex E1E2 from an HCV-immune phage-display antibody library by using an exhaustive-panning strategy. Many of these mAbs were broadly neutralizing. In particular, the mAb AR4A, recognizing a discontinuous epitope outside the CD81......bs on the E1E2 complex, has an exceptionally broad neutralizing activity toward diverse HCV genotypes and protects against heterologous HCV challenge in a small animal model. The mAb panel will be useful for the design and development of vaccine candidates to elicit broadly neutralizing antibodies...

CO2 line-mixing database and software update and its tests in the 2.1 μm and 4.3 μm regions

International Nuclear Information System (INIS)

Lamouroux, J.; Régalia, L.; Thomas, X.; Vander Auwera, J.; Gamache, R.R.; Hartmann, J.-M.

2015-01-01

An update of the former version of the database and software for the calculation of CO 2 –air absorption coefficients taking line-mixing into account [Lamouroux et al. J Quant Spectrosc Radiat Transf 2010;111:2321] is described. In this new edition, the data sets were constructed using parameters from the 2012 version of the HITRAN database and recent measurements of line-shape parameters. Among other improvements, speed-dependent profiles can now be used if line-mixing is treated within the first order approximation. This new package is tested using laboratory spectra measured in the 2.1 μm and 4.3 μm spectral regions for various pressures, temperatures and CO 2 concentration conditions. Despite improvements at 4.3 μm at room temperature, the conclusions on the quality of this update are more ambiguous at low temperature and in the 2.1 μm region. Further tests using laboratory and atmospheric spectra are thus required for the evaluation of the performances of this updated package. - Highlights: • High resolution infrared spectroscopy. • CO 2 in air. • Updated tools. • Line mixing database and software

Anisotropic ionizing radiation in Seyfert galaxies. I - The extended narrow-line region in Markarian 573

Science.gov (United States)

Tsvetanov, Zlatan; Walsh, J. R.

1992-01-01

The morphology, kinematics, and ionization state of the nuclear extended narrow-line region (ENLR) of the Seyfert 2 galaxy Mrk 573 are studied using narrow-band images of a grid of long-slit spectra. The entire ENLR is mapped spectroscopically, and velocity structure is studied. The velocity field map shows a typical galactic rotation picture with some important deviations. A simple geometric model, in accordance with the 'unified schemes', is employed to study the effects of various parameters of the observed picture. The best match is achieved when a biconical radiation field illuminates the ISM of the host galaxy that takes part in a normal galaxy rotation but also has radial motions close to the nucleus. The emission-line images reveal an ENLR elongated along the radio axis in the northwest-southeast direction, but a map of the flux ratio forbidden O III 5007/(H-alpha + forbidden N II) shows a different structure, with the highest excitation peak offset by about 4 arcsec along the radio axis to the southeast.

The ATCA CABB Line Survey on Centaurus A: Properties of the Molecular Gas from the Dust Lanes to the Central Engine

Science.gov (United States)

Ott, Juergen; Koribalski, Baerbel; Henkel, Christian; Edwards, Philip; Norris, Ray; Meier, David; Feain, Ilana; Curran, Steve; Martin-Pintado, Jesus; Beelen, Alexandre; Aalto, Susanne; Combes, Francoise; Israel, Frank; Muller, Sebastien; Espada, Daniel; Guelin, Michel; Black, John Harry; V-Trung, Dinh; Impellizzeri, Caterina M. V.; Persson, Carina

2011-10-01

Centaurus A with its host NGC5128 is the most nearby radio galaxy. Its molecular spectrum exhibits three prominent features: a) gas that is located in the outer disk and dust lanes, b) absorption lines that are supposedly close to the central AGN, and c) gas in emission from the nucleus. We propose to perform an extensive line survey toward CenA using the exciting new capabilities of CABB. The broad basebands and narrow zoom bands of CABB are ideal to capture the full breath of the CenA spectral features. Our multi-band line observations will allow us to derive the exact physical conditions of each component as well as the chemistry involved. We will therefore obtain a comprehensive view of the physics imprinted on the molecular spectrum of a radio galaxy and its host, reaching from the central supermassive black hole, through the accretion region and the inner disk to the outer dust lanes.

An XMM-Newton Study of the Bright Ultrasoft Narrow-Line Quasar NAB 0205+024

Science.gov (United States)

Brandt, Niel

2004-01-01

The broad-band X-ray continuum of NAB 0205424 is well constrained due to the excellent photon statistics obtained (about 97,700 counts), and its impressive soft X-ray excess is clearly apparent. The hard X-ray power law has become notably steeper than when NAB 0205424 was observed with ASCA, attesting to the presence of significant X-ray spectral variability. A strong and broad emission feature is detected from about 5 to 6.4 keV, and we have modeled this as a relativistic line emitted close to the black hole from a narrow annulus of the accretion disk. Furthermore, a strong X-ray flare is detected with a hard X-ray spectrum; this flare may be responsible for illuminating the inner line-emitting part of the accretion disk. The combined observational results can be broadly interpreted in terms of the "thundercloud model proposed by Merloni & Fabian (2001).

Fermi monitoring of radio-loud narrow-line Seyfert 1 galaxies

Energy Technology Data Exchange (ETDEWEB)

Paliya, Vaidehi S.; Stalin, C. S. [Indian Institute of Astrophysics, Block II, Koramangala, Bangalore-560034 (India); Ravikumar, C. D., E-mail: vaidehi@iiap.res.in [Department of Physics, University of Calicut, Malappuram-673635 (India)

2015-02-01

We present detailed analysis of the γ-ray flux variability and spectral properties of the five radio-loud narrow line Seyfert 1 (RL-NLSy1) galaxies, detected by the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope, namely 1H 0323+342, SBS 0846+513, PMN J0948+0022, PKS 1502+036, and PKS 2004−447. The first three sources show significant flux variations, including the rapid variability of a few hours by 1H 0323+342. The average γ-ray spectrum of 1H 0323+342 and PMN J0948+0022 shows deviation from a simple power-law (PL) behavior, whereas the PL model gives a better fit for the other three sources. The spectra of 1H 0323+342, SBS 0846+513, and PMN J0948+0022, which are in low, flaring, and moderately active states, respectively, show significant curvature. Such curvature in the γ-ray spectrum of 1H 0323+342 and PMN J0948+0022 could be due to the emission region located inside the broad line region (BLR) where the primary mechanism of the γ-ray emission is inverse-Compton (IC) scattering of BLR photons occurring in the Klein–Nishina regime. The γ-ray emission of SBS 0846+513 is explained by IC scattering of dusty torus photons, which puts the emission region outside the BLR and thus under the Thomson regime. Therefore, the observed curvature of SBS 0846+513 could be intrinsic to the particle energy distribution. The presence of curvature in the γ-ray spectrum and flux variability amplitudes of some of the RL-NLSy1 galaxies suggests that these sources could be akin to low/moderate jet power flat spectrum radio quasars.

Fermi monitoring of radio-loud narrow-line Seyfert 1 galaxies

International Nuclear Information System (INIS)

Paliya, Vaidehi S.; Stalin, C. S.; Ravikumar, C. D.

2015-01-01

We present detailed analysis of the γ-ray flux variability and spectral properties of the five radio-loud narrow line Seyfert 1 (RL-NLSy1) galaxies, detected by the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope, namely 1H 0323+342, SBS 0846+513, PMN J0948+0022, PKS 1502+036, and PKS 2004−447. The first three sources show significant flux variations, including the rapid variability of a few hours by 1H 0323+342. The average γ-ray spectrum of 1H 0323+342 and PMN J0948+0022 shows deviation from a simple power-law (PL) behavior, whereas the PL model gives a better fit for the other three sources. The spectra of 1H 0323+342, SBS 0846+513, and PMN J0948+0022, which are in low, flaring, and moderately active states, respectively, show significant curvature. Such curvature in the γ-ray spectrum of 1H 0323+342 and PMN J0948+0022 could be due to the emission region located inside the broad line region (BLR) where the primary mechanism of the γ-ray emission is inverse-Compton (IC) scattering of BLR photons occurring in the Klein–Nishina regime. The γ-ray emission of SBS 0846+513 is explained by IC scattering of dusty torus photons, which puts the emission region outside the BLR and thus under the Thomson regime. Therefore, the observed curvature of SBS 0846+513 could be intrinsic to the particle energy distribution. The presence of curvature in the γ-ray spectrum and flux variability amplitudes of some of the RL-NLSy1 galaxies suggests that these sources could be akin to low/moderate jet power flat spectrum radio quasars.

Database of emission lines

Science.gov (United States)

Binette, L.; Ortiz, P.; Joguet, B.; Rola, C.

1998-11-01

A widely accessible data bank (available through Netscape) and consiting of all (or most) of the emission lines reported in the litterature is being built. It will comprise objects as diverse as HII regions, PN, AGN, HHO. One of its use will be to define/refine existing diagnostic emission line diagrams.

Mapping Plant Functional Types over Broad Mountainous Regions: A Hierarchical Soft Time-Space Classification Applied to the Tibetan Plateau

Directory of Open Access Journals (Sweden)

Danlu Cai

2014-04-01

Full Text Available Research on global climate change requires plant functional type (PFT products. Although several PFT mapping procedures for remote sensing imagery are being used, none of them appears to be specifically designed to map and evaluate PFTs over broad mountainous areas which are highly relevant regions to identify and analyze the response of natural ecosystems. We present a methodology for generating soft classifications of PFTs from remotely sensed time series that are based on a hierarchical strategy by integrating time varying integrated NDVI and phenological information with topography: (i Temporal variability: a Fourier transform of a vegetation index (MODIS NDVI, 2006 to 2010. (ii Spatial partitioning: a primary image segmentation based on a small number of thresholds applied to the Fourier amplitude. (iii Classification by a supervised soft classification step is based on a normalized distance metric constructed from a subset of Fourier coefficients and complimentary altitude data from a digital elevation model. Applicability and effectiveness is tested for the eastern Tibetan Plateau. A classification nomenclature is determined from temporally stable pixels in the MCD12Q1 time series. Overall accuracy statistics of the resulting classification reveal a gain of about 7% from 64.4% compared to 57.7% by the MODIS PFT products.

Metabolic and molecular changes of the phenylpropanoid pathway in tomato (Solanum lycopersicum lines carrying different Solanum pennellii wild chromosomal regions

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Maria Manuela Rigano

2016-10-01

Full Text Available Solanum lycopersicum represents an important dietary source of bioactive compounds including the antioxidants flavonoids and phenolic acids. We previously identified two genotypes (IL7-3 and IL12-4 carrying loci from the wild species Solanum pennellii, which increased antioxidants in the fruit. Successively, these lines were crossed and two genotypes carrying both introgressions at the homozygous condition (DHO88 and DHO88-SL were selected. The amount of total antioxidant compounds was increased in DHOs compared to both ILs and the control genotype M82. In order to understand the genetic mechanisms underlying the positive interaction between the two wild regions pyramided in DHO genotypes, detailed analyses of the metabolites accumulated in the fruit were carried out by colorimetric methods and LC/MS/MS. These analyses evidenced a lower content of flavonoids in DHOs and in ILs, compared to M82. By contrast, in the DHOs the relative content of phenolic acids increased, particularly the fraction of hexoses, thus evidencing a redirection of the phenylpropanoid flux towards the biosynthesis of phenolic acid glycosides in these genotypes. In addition, the line DHO88 exhibited a lower content of free phenolic acids compared to M82. Interestingly, the two DHOs analyzed differ in the size of the wild region on chromosome 12. Genes mapping in the introgression regions were further investigated. Several genes of the phenylpropanoid biosynthetic pathway were identified, such as one 4-coumarate:CoA ligase and two UDP-glycosyltransferases in the region 12-4 and one chalcone isomerase and one UDP-glycosyltransferase in the region 7-3. Transcriptomic analyses demonstrated a different expression of the detected genes in the ILs and in the DHOs compared to M82.These analyses, combined with biochemical analyses, suggested a central role of the 4-coumarate:CoA ligase in redirecting the phenylpropanoid pathways towards the biosynthesis of phenolic acids in the

CORRELATION ANALYSIS OF A LARGE SAMPLE OF NARROW-LINE SEYFERT 1 GALAXIES: LINKING CENTRAL ENGINE AND HOST PROPERTIES

International Nuclear Information System (INIS)

Xu Dawei; Komossa, S.; Wang Jing; Yuan Weimin; Zhou Hongyan; Lu Honglin; Li Cheng; Grupe, Dirk

2012-01-01

We present a statistical study of a large, homogeneously analyzed sample of narrow-line Seyfert 1 (NLS1) galaxies, accompanied by a comparison sample of broad-line Seyfert 1 (BLS1) galaxies. Optical emission-line and continuum properties are subjected to correlation analyses, in order to identify the main drivers of the correlation space of active galactic nuclei (AGNs), and of NLS1 galaxies in particular. For the first time, we have established the density of the narrow-line region as a key parameter in Eigenvector 1 space, as important as the Eddington ratio L/L Edd . This is important because it links the properties of the central engine with the properties of the host galaxy, i.e., the interstellar medium (ISM). We also confirm previously found correlations involving the line width of Hβ and the strength of the Fe II and [O III] λ5007 emission lines, and we confirm the important role played by L/L Edd in driving the properties of NLS1 galaxies. A spatial correlation analysis shows that large-scale environments of the BLS1 and NLS1 galaxies of our sample are similar. If mergers are rare in our sample, accretion-driven winds, on the one hand, or bar-driven inflows, on the other hand, may account for the strong dependence of Eigenvector 1 on ISM density.

Eta Carinae: Linelist for the Emission Spectrum of the Weigelt Blobs in the 1700-10400Angstrom Wavelength Region

Science.gov (United States)

Zethson, T.; Johansson, S.; Hartman, H.; Gull, T. R.

2011-01-01

Aims. We present line identifications in the 1700 to 10400A region for the Weigelt Blobs B and D, located 0.1 to 0.3" NNW of Eta Carinae. The aim of this work is to characterize the behavior of these luminous, dense gas condensations in response to the broad maximum and short minimum states of Eta Carinae during its 5.54-year spectroscopic period. Methods. The observations were carried out during March 1998, the minimum spectrum, and in February 1999, early maximum spectrum, with the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) from 1640 to 10400A using the 52"x0.1" aperture centered on Eta Carinae at position angle -28 degrees. Extractions of the reduced spectrum centered on Weigelt B and D, 0.28: in length along the slit, were used to identify the narrow, nebular emission lines, measure their wavelengths and estimate their fluxes. Results. A linelist of 1500 lines is presented for the maximum and minimum states of combined Weigelt blobs B and D. The spectra are dominated by emission lines from the iron-group elements, but include lines from lighter elements. They include parity permitted and forbidden lines. A number of lines are fluorescent lines pumped by H Ly alpha. Other lines show anomalous excitation.

Limit lines for risk

International Nuclear Information System (INIS)

Cox, D.C.; Baybutt, P.

1982-01-01

Approaches to the regulation of risk from technological systems, such as nuclear power plants or chemical process plants, in which potential accidents may result in a broad range of adverse consequences must take into account several different aspects of risk. These include overall or average risk, accidents posing high relative risks, the rate at which accident probability decreases with increasing accident consequences, and the impact of high frequency, low consequence accidents. A hypothetical complementary cumulative distribution function (CCDF), with appropriately chosen parametric form, meets all these requirements. The Farmer limit line, by contrast, places limits on the risks due to individual accident sequences, and cannot adequately account for overall risk. This reduces its usefulness as a regulatory tool. In practice, the CCDF is used in the Canadian nuclear licensing process, while the Farmer limit line approach, supplemented by separate qualitative limits on overall risk, is employed in the United Kingdom

HOT GAS LINES IN T TAURI STARS

International Nuclear Information System (INIS)

Ardila, David R.; Herczeg, Gregory J.; Gregory, Scott G.; Hillenbrand, Lynne A.; Ingleby, Laura; Bergin, Edwin; Bethell, Thomas; Calvet, Nuria; France, Kevin; Brown, Alexander; Edwards, Suzan; Johns-Krull, Christopher; Linsky, Jeffrey L.; Yang, Hao; Valenti, Jeff A.; Abgrall, Hervé; Alexander, Richard D.; Brown, Joanna M.; Espaillat, Catherine; Hussain, Gaitee

2013-01-01

For Classical T Tauri Stars (CTTSs), the resonance doublets of N V, Si IV, and C IV, as well as the He II 1640 Å line, trace hot gas flows and act as diagnostics of the accretion process. In this paper we assemble a large high-resolution, high-sensitivity data set of these lines in CTTSs and Weak T Tauri Stars (WTTSs). The sample comprises 35 stars: 1 Herbig Ae star, 28 CTTSs, and 6 WTTSs. We find that the C IV, Si IV, and N V lines in CTTSs all have similar shapes. We decompose the C IV and He II lines into broad and narrow Gaussian components (BC and NC). The most common (50%) C IV line morphology in CTTSs is that of a low-velocity NC together with a redshifted BC. For CTTSs, a strong BC is the result of the accretion process. The contribution fraction of the NC to the C IV line flux in CTTSs increases with accretion rate, from ∼20% to up to ∼80%. The velocity centroids of the BCs and NCs are such that V BC ∼> 4 V NC , consistent with the predictions of the accretion shock model, in at most 12 out of 22 CTTSs. We do not find evidence of the post-shock becoming buried in the stellar photosphere due to the pressure of the accretion flow. The He II CTTSs lines are generally symmetric and narrow, with FWHM and redshifts comparable to those of WTTSs. They are less redshifted than the CTTSs C IV lines, by ∼10 km s –1 . The amount of flux in the BC of the He II line is small compared to that of the C IV line, and we show that this is consistent with models of the pre-shock column emission. Overall, the observations are consistent with the presence of multiple accretion columns with different densities or with accretion models that predict a slow-moving, low-density region in the periphery of the accretion column. For HN Tau A and RW Aur A, most of the C IV line is blueshifted suggesting that the C IV emission is produced by shocks within outflow jets. In our sample, the Herbig Ae star DX Cha is the only object for which we find a P-Cygni profile in the C IV

Temperature Dependences of the Quantum-Mechanical and Semi-Classical Spectral-Line Widths and the Separation 0 of the Impact and Non-Impact Regions for an Ar-Perturbed/K-Radiator System

Directory of Open Access Journals (Sweden)

W. C. Kreye

2010-01-01

Full Text Available Quantum-mechanical and semi-classical spectral-line shapes are computed at =400, 800, and 1000 K for the line core of the 5802 Å line of the Ar-Perturbed/K-Radiator system. HWHMs ('s are measured from computed full spectral-line shapes. The final-state pseudopotential is for the 721/2 state, and the initial-state potential is for the 423/2,3/2 state. Three high-pressure (P log(—versus—log( curves, corresponding to the non-impact region, intersect a similar set of low-P, impact-region curves at intersections, 0's. Similarly, for two sets of log(—versus—log( curves, which yield intersections, 0's, where is the perturber density. These 0's and 0's separate the two regions and represent the upper limits of the impact regions. A specific validity condition for the impact region is given by the equation ≤0. From an earlier spectroscopic, Fabry-Perot paper, expt=0.021 cm−1 at =400 K and =10 torr. Two theoretical values, theor=0.025 and 0.062 cm−1 corresponding to two different pseudo-potentials, are reported. Two -dependent figures are given, in which the first shows an increase in the impact region with , based on as the basic parameter, and the second which shows a decrease in the impact region with , based on as the basic parameter.

Design of 2.5 GHz broad bandwidth microwave bandpass filter at operating frequency of 10 GHz using HFSS

Science.gov (United States)

Jasim, S. E.; Jusoh, M. A.; Mahmud, S. N. S.; Zamani, A. H.

2018-04-01

Development of low losses, small size and broad bandwidth microwave bandpass filter operating at higher frequencies is an active area of research. This paper presents a new route used to design and simulate microwave bandpass filter using finite element modelling and realized broad bandwidth, low losses, small dimension microwave bandpass filter operating at 10 GHz frequency using return loss method. The filter circuit has been carried out using Computer Aid Design (CAD), Ansoft HFSS software and designed with four parallel couple line model and small dimension (10 × 10 mm2) using LaAlO3 substrate. The response of the microwave filter circuit showed high return loss -50 dB at operating frequency at 10.4 GHz and broad bandwidth of 2.5 GHz from 9.5 to 12 GHz. The results indicate the filter design and simulation using HFSS is reliable and have the opportunity to transfer from lab potential experiments to the industry.

77 FR 50144 - Broad Stakeholder Survey

Science.gov (United States)

2012-08-20

... DEPARTMENT OF HOMELAND SECURITY [Docket No. DHS-2012-0042] Broad Stakeholder Survey AGENCY... Information Collection Request: 1670-NEW. SUMMARY: The Department of Homeland Security (DHS), National... (Pub. L. 104-13, 44 U.S.C. Chapter 35). NPPD is soliciting comments concerning the Broad Stakeholder...

76 FR 34087 - Broad Stakeholder Survey

Science.gov (United States)

2011-06-10

... DEPARTMENT OF HOMELAND SECURITY [Docket No. DHS-2011-0027] Broad Stakeholder Survey AGENCY... Information Collection Request: 1670-NEW. SUMMARY: The Department of Homeland Security (DHS), National... (Pub. L. 104-13, 44 U.S.C. Chapter 35). NPPD is soliciting comments concerning the Broad Stakeholder...

The effects of exogenous catalase on broad-spectrum near-UV (300-400nm) treated Escherichia coli cells

International Nuclear Information System (INIS)

Sammartano, L.J.; Tuveson, R.W.

1984-01-01

Catalase incorporated into plating medium protects against inactivation and mutagenesis by broad-spectrum near-ultraviolet wavelength (300-400nm) (NUV) radiation in strains of Escherichia coli. Plating medium containing catalase does not provide protection against inactivation by wavelengths in the FUV region. Catalase added to the cell suspension during or added immediately after NUV exposure also protects against inactivation. The protection provided by catalase suggests a possible role for hydrogen peroxide in the processes of inactivation and mutagenesis by broad-spectrum NUV. (author)

Radio recombination lines from H+ regions and cold interstellar clouds: computation of the bsub(n) factors

International Nuclear Information System (INIS)

Brocklehurst, M.; Salem, M.

1977-01-01

Emission lines produced by the recombination of hydrogen and hydrogenic ions are observed from many astronomical sources; maser amplification is frequently present. The recombination line spectrum depends upon the populations of the energy levels of the emitting species. The present program computes the ratio, bsub(n), of the population of energy level n to the (known) population in thermodynamic equilibrium for given values of electron temperature and density. A background radiation field may be present. The results are accurate for the range of temperatures and densities associated with cold clouds, H + regions, and planetary nebulae (10-20000 K, 10 -4 -10 6 cm -3 ). The method is that described by Brocklehurst but with the collision cross-sections of Gee et al. In statistical equilibrium, the rates of population and depopulation of each of the infinitely many energy levels must be equal. The infinite system of linear algebraic equations thus defined is truncated, and correction terms are added to compensate for the omitted levels. The resulting system is condensed to a smaller size and solved. The equations of radiative transfer must in principle be solved simultaneously with the population equations. In practice it is uaually sufficient to consider the optical depth for each line to be either zero (no absorption) or infinite (on-the-spot absorption). (Auth.)

Fourier transform measurements of water vapor line parameters in the 4200-6600 cm{sup -1} region

Energy Technology Data Exchange (ETDEWEB)

Jenouvrier, Alain [Groupe de Spectrometrie Moleculaire et Atmospherique, UMR CNRS 6089, UFR Sciences, Moulin de la Housse, B.P. 1039, 51067 Reims Cedex 2 (France)]. E-mail: alain.jenouvrier@univ-reims.fr; Daumont, Ludovic [Groupe de Spectrometrie Moleculaire et Atmospherique, UMR CNRS 6089, UFR Sciences, Moulin de la Housse, B.P. 1039, 51067 Reims Cedex 2 (France); Regalia-Jarlot, Laurence [Groupe de Spectrometrie Moleculaire et Atmospherique, UMR CNRS 6089, UFR Sciences, Moulin de la Housse, B.P. 1039, 51067 Reims Cedex 2 (France); Tyuterev, Vladimir G. [Groupe de Spectrometrie Moleculaire et Atmospherique, UMR CNRS 6089, UFR Sciences, Moulin de la Housse, B.P. 1039, 51067 Reims Cedex 2 (France); Carleer, Michel [Service de Chimie Quantique et de Photophysique, CP 160/09, Universite Libre de Bruxelles, 50 Av. F.D. Roosevelt, B-1050 Brussels (Belgium); Vandaele, Ann Carine [Institut d' Aeronomie Spatiale de Belgique, Av. Circulaire 3, B-1180 Brussels (Belgium); Mikhailenko, Semen [Laboratory of Theoretical Spectroscopy, Institute of Atmospheric Optics, Russian Academy of Sciences, 1, Av. Akademichesskii, 634055 Tomsk (Russian Federation); Fally, Sophie [Service de Chimie Quantique et de Photophysique, CP 160/09, Universite Libre de Bruxelles, 50 Av. F.D. Roosevelt, B-1050 Brussels (Belgium)

2007-06-15

New high-resolution water vapor absorption spectra were obtained at room temperature in the 4200-6600 cm{sup -1} spectral region by combining Fourier transform spectrometers (FTS) with single and multiple reflection cells. With absorption paths from 0.3 to 1800 m in pure and air diluted water vapor, accurate measurements of about 10400 lines in an intensity range from 10{sup -29} to 10{sup -19} cm/molecule have been performed. Positions, intensities, self- and air-broadening coefficients and air-induced shifts were determined for the H{sub 2} {sup 16}O, H{sub 2} {sup 17}O, H{sub 2} {sup 18}O and HDO isotopologues. The rovibrational assignment of the observed lines was performed with the use of global variational predictions and allowed the identification of several new energy levels. One major contribution of this work consists of the identification of 3280 new weak lines. A very close agreement between the new measured parameters and those listed in the database is reported as well as between the observations and the most recent variational calculations for the positions and the intensities. The present parameters provide an extended and homogeneous data set for water vapor, which is shown to significantly improve the databases for atmospheric applications, especially in the transmission windows on both sides of the band centered at 5400 cm{sup -1}.

The peculiar radio-loud narrow line Seyfert 1 galaxy 1H 0323+342

Energy Technology Data Exchange (ETDEWEB)

Paliya, Vaidehi S.; Stalin, C. S. [Indian Institute of Astrophysics, Block-II, Koramangala, Bangalore-560034 (India); Sahayanathan, S. [Astrophysical Science Division, Bhabha Atomic Research Center, Mumbai-400085 (India); Parker, M. L.; Fabian, A. C. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Anjum, Ayesha [Department of Physics, Christ University, Bangalore-560029 (India); Pandey, S. B., E-mail: vaidehi@iiap.res.in [Aryabhatta Research Institute of Observational Sciences, Manora peak, Nainital-263129 (India)

2014-07-10

We present a multiwavelength study of the radio-loud narrow-line Seyfert 1 galaxy (NLSy1) 1H 0323+342, detected by the Fermi Gamma-Ray Space Telescope. Multiband light curves show many orphan X-ray and optical flares having no corresponding γ-ray counterparts. Such anomalous variability behavior can be due to different locations of the emission region from the central source. During a large flare, a γ-ray flux doubling timescale as small as ∼3 hr is noticed. We built spectral energy distributions (SEDs) during different activity states and modeled them using a one-zone leptonic model. The shape of the optical/UV component of the SEDs is dominated by accretion disk emission in all the activity states. In the X-ray band, significant thermal emission from the hot corona is inferred during quiescent and first flaring states; however, during subsequent flares, the nonthermal jet component dominates. The γ-ray emission in all the states can be well explained by inverse-Compton scattering of accretion disk photons reprocessed by the broad-line region. The source showed violent intra-night optical variability, coinciding with one of the high γ-ray activity states. An analysis of the overall X-ray spectrum fitted with an absorbed power-law plus relativistic reflection component hints at the presence of an Fe Kα line and returns a high black hole spin value of a = 0.96 ± 0.14. We argue that 1H 0323+342 possesses dual characteristics, akin to both flat-spectrum radio quasars (FSRQs) and radio-quiet NLSy1 galaxies, though at a low jet power regime compared to powerful FSRQs.

THE NEAR-INFRARED CORONAL LINE SPECTRUM OF 54 NEARBY ACTIVE GALACTIC NUCLEI

International Nuclear Information System (INIS)

Rodríguez-Ardila, A.; Prieto, M. A.; Portilla, J. G.; Tejeiro, J. M.

2011-01-01

The relationship between the emission of coronal lines (CLs) and nuclear activity in 36 Type 1 and 18 Type 2 active galactic nuclei (AGNs) is analyzed, for the first time, based on near-infrared (0.8-2.4 μm) spectra. The eight CLs studied, of Si, S, Fe, Al, and Ca elements and corresponding to ionization potentials (IPs) in the range 125-450 eV, are detected (3σ) in 67% (36 AGNs) of the sample. Our analysis shows that the four most frequent CLs [Si VI] 1.963 μm, [S VIII] 0.9913 μm, [S IX] 1.252 μm, and [Si X] 1.430 μm display a narrow range in luminosity, with most lines located in the interval log L 39-40 erg s –1 . We found that the non-detection is largely associated with either loss of spatial resolution or increasing object distance: CLs are essentially nuclear and easily lose contrast in the continuum stellar light for nearby sources or get diluted by the strong AGN continuum as the redshift increases. Yet, there are AGNs where the lack of coronal emission, i.e., lines with IP ≥ 100 eV, may be genuine. The absence of these lines reflects a non-standard AGN ionizing continuum, namely, a very hard spectrum lacking photons below a few Kev. The analysis of the line profiles points out a trend of increasing FWHM with increasing IPs up to energies around 300 eV, where a maximum in the FWHM is reached. For higher IP lines, the FWHM remains nearly constant or decreases with increasing IPs. We ascribe this effect to an increasing density environment as we approach the innermost regions of these AGNs, where densities above the critical density of the CLs with IPs larger than 300 eV are reached. This sets a strict range limit for the density in the boundary region between the narrow and the broad region of 10 8 -10 9 cm –3 . A relationship between the luminosity of the CLs and that of the soft and hard X-ray emission and the soft X-ray photon index is observed: the coronal emission becomes stronger with both increasing X-ray emission (soft and hard) and

Molecular hydrogen line ratios in four regions of shock-excited gas

International Nuclear Information System (INIS)

Burton, M.G.

1989-01-01

Five emission lines of molecular hydrogen, with wavelengths in the ranges of 2.10-2.25 and 3.80-3.85 μm, have been observed in four objects of different type in which the line emission is believed to be excited by shocks. (author)

THE CORES OF THE Fe Kα LINES IN ACTIVE GALACTIC NUCLEI: AN EXTENDED CHANDRA HIGH ENERGY GRATING SAMPLE

International Nuclear Information System (INIS)

Shu, X. W.; Wang, J. X.; Yaqoob, T.

2010-01-01

We extend the study of the core of the Fe Kα emission line at ∼6.4 keV in Seyfert galaxies reported by Yaqoob and Padmanabhan using a larger sample observed by the Chandra high-energy grating (HEG). The sample consists of 82 observations of 36 unique sources with z H 23 cm -2 ) Seyfert galaxies to date. From an empirical and uniform analysis, we present measurements of the Fe Kα line centroid energy, flux, equivalent width (EW), and intrinsic width (FWHM). The Fe Kα line is detected in 33 sources, and its centroid energy is constrained in 32 sources. In 27 sources, the statistical quality of the data is good enough to yield measurements of the FWHM. We find that the distribution in the line centroid energy is strongly peaked around the value for neutral Fe, with over 80% of the observations giving values in the range 6.38-6.43 keV. Including statistical errors, 30 out of 32 sources (∼94%) have a line centroid energy in the range 6.35-6.47 keV. The mean EW, among the observations in which a non-zero lower limit could be measured, was 53 ± 3 eV. The mean FWHM from the subsample of 27 sources was 2060 ± 230 km s -1 . The mean EW and FWHM are somewhat higher when multiple observations for a given source are averaged. From a comparison with the Hβ optical emission-line widths (or, for one source, Brα), we find that there is no universal location of the Fe Kα line-emitting region relative to the optical broad-line region (BLR). In general, a given source may have contributions to the Fe Kα line flux from parsec-scale distances from the putative black hole, down to matter a factor ∼2 closer to the black hole than the BLR. We confirm the presence of the X-ray Baldwin effect, an anti-correlation between the Fe Kα line EW and X-ray continuum luminosity. The HEG data have enabled isolation of this effect to the narrow core of the Fe Kα line.

Rates and factors associated with major modifications to first-line combination antiretroviral therapy: results from the Asia-Pacific region.

Directory of Open Access Journals (Sweden)

Stephen Wright

Full Text Available In the Asia-Pacific region many countries have adopted the WHO's public health approach to HIV care and treatment. We performed exploratory analyses of the factors associated with first major modification to first-line combination antiretroviral therapy (ART in resource-rich and resource-limited countries in the region.We selected treatment naive HIV-positive adults from the Australian HIV Observational Database (AHOD and the TREAT Asia HIV Observational Database (TAHOD. We dichotomised each country's per capita income into high/upper-middle (T-H and lower-middle/low (T-L. Survival methods stratified by income were used to explore time to first major modification of first-line ART and associated factors. We defined a treatment modification as either initiation of a new class of antiretroviral (ARV or a substitution of two or more ARV agents from within the same ARV class.A total of 4250 patients had 961 major modifications to first-line ART in the first five years of therapy. The cumulative incidence (95% CI of treatment modification was 0.48 (0.44-0.52, 0.33 (0.30-0.36 and 0.21 (0.18-0.23 for AHOD, T-H and T-L respectively. We found no strong associations between typical patient characteristic factors and rates of treatment modification. In AHOD, relative to sites that monitor twice-yearly (both CD4 and HIV RNA-VL, quarterly monitoring corresponded with a doubling of the rate of treatment modifications. In T-H, relative to sites that monitor once-yearly (both CD4 and HIV RNA-VL, monitoring twice-yearly corresponded to a 1.8 factor increase in treatment modifications. In T-L, no sites on average monitored both CD4 & HIV RNA-VL concurrently once-yearly. We found no differences in rates of modifications for once- or twice-yearly CD4 count monitoring.Low-income countries tended to have lower rates of major modifications made to first-line ART compared to higher-income countries. In higher-income countries, an increased rate of RNA-VL monitoring was

Similarity law for Widom lines and coexistence lines.

Science.gov (United States)

Banuti, D T; Raju, M; Ihme, M

2017-05-01

The coexistence line of a fluid separates liquid and gaseous states at subcritical pressures, ending at the critical point. Only recently, it became clear that the supercritical state space can likewise be divided into regions with liquidlike and gaslike properties, separated by an extension to the coexistence line. This crossover line is commonly referred to as the Widom line, and is characterized by large changes in density or enthalpy, manifesting as maxima in the thermodynamic response functions. Thus, a reliable representation of the coexistence line and the Widom line is important for sub- and supercritical applications that depend on an accurate prediction of fluid properties. While it is known for subcritical pressures that nondimensionalization with the respective species critical pressures p_{cr} and temperatures T_{cr} only collapses coexistence line data for simple fluids, this approach is used for Widom lines of all fluids. However, we show here that the Widom line does not adhere to the corresponding states principle, but instead to the extended corresponding states principle. We resolve this problem in two steps. First, we propose a Widom line functional based on the Clapeyron equation and derive an analytical, species specific expression for the only parameter from the Soave-Redlich-Kwong equation of state. This parameter is a function of the acentric factor ω and compares well with experimental data. Second, we introduce the scaled reduced pressure p_{r}^{*} to replace the previously used reduced pressure p_{r}=p/p_{cr}. We show that p_{r}^{*} is a function of the acentric factor only and can thus be readily determined from fluid property tables. It collapses both subcritical coexistence line and supercritical Widom line data over a wide range of species with acentric factors ranging from -0.38 (helium) to 0.34 (water), including alkanes up to n-hexane. By using p_{r}^{*}, the extended corresponding states principle can be applied within

Broad Prize: Do the Successes Spread?

Science.gov (United States)

Samuels, Christina A.

2011-01-01

When the Broad Prize for Urban Education was created in 2002, billionaire philanthropist Eli Broad said he hoped the awards, in addition to rewarding high-performing school districts, would foster healthy competition; boost the prestige of urban education, long viewed as dysfunctional; and showcase best practices. Over the 10 years the prize has…

THE ROLE OF RADIATION PRESSURE IN THE NARROW LINE REGIONS OF SEYFERT HOST GALAXIES

Energy Technology Data Exchange (ETDEWEB)

Davies, Rebecca L.; Dopita, Michael A.; Kewley, Lisa; Groves, Brent; Sutherland, Ralph; Hampton, Elise J.; Banfield, Julie [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Shastri, Prajval; Kharb, Preeti; Bhatt, Harish [Indian Institute of Astrophysics, Sarjapur Road, Bengaluru 560034 (India); Scharwächter, Julia [LERMA, Observatoire de Paris, PSL, CNRS, Sorbonne Universités, UPMC, F-75014 Paris (France); Jin, Chichuan [Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Zaw, Ingyin [New York University (Abu Dhabi), 70 Washington Square S, New York, NY 10012 (United States); James, Bethan [Institute of Astronomy, Cambridge University, Madingley Road, Cambridge CB3 0HA (United Kingdom); Juneau, Stéphanie [CEA-Saclay, DSM/IRFU/SAp, F-91191 Gif-sur-Yvette (France); Srivastava, Shweta, E-mail: Rebecca.Davies@anu.edu.au [Astronomy and Astrophysics Division, Physical Research Laboratory, Ahmedabad 380009 (India)

2016-06-10

We investigate the relative significance of radiation pressure and gas pressure in the extended narrow line regions (ENLRs) of four Seyfert galaxies from the integral field Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). We demonstrate that there exist two distinct types of starburst-active galactic nucleus (AGN) mixing curves on standard emission line diagnostic diagrams, which reflect the balance between gas pressure and radiation pressure in the ENLR. In two of the galaxies the ENLR is radiation pressure dominated throughout and the ionization parameter remains constant (log U ∼ 0). In the other two galaxies radiation pressure is initially important, but gas pressure becomes dominant as the ionization parameter in the ENLR decreases from log U ∼ 0 to −3.2 ≲ log U ≲ −3.4. Where radiation pressure is dominant, the AGN regulates the density of the interstellar medium on kiloparsec scales and may therefore have a direct impact on star formation activity and/or the incidence of outflows in the host galaxy to scales far beyond the zone of influence of the black hole. We find that both radiation pressure dominated and gas pressure dominated ENLRs are dynamically active with evidence for outflows, indicating that radiation pressure may be an important source of AGN feedback even when it is not dominant over the entire ENLR.

The Discovery of a High-Redshift Quasar without Emission Lines from Sloan Digital Sky Survey Commissioning Data.

Science.gov (United States)

Fan; Strauss; Gunn; Lupton; Carilli; Rupen; Schmidt; Moustakas; Davis; Annis; Bahcall; Brinkmann; Brunner; Csabai; Doi; Fukugita; Heckman; Hennessy; Hindsley; Ivezic; Knapp; Lamb; Munn; Pauls; Pier; Rockosi; Schneider; Szalay; Tucker; York

1999-12-01

We report observations of a luminous unresolved object at redshift z=4.62, with a featureless optical spectrum redward of the Lyalpha forest region, discovered from Sloan Digital Sky Survey commissioning data. The redshift is determined by the onset of the Lyalpha forest at lambda approximately 6800 Å and a Lyman limit system at lambda=5120 Å. A strong Lyalpha absorption system with weak metal absorption lines at z=4.58 is also identified in the spectrum. The object has a continuum absolute magnitude of -26.6 at 1450 Å in the rest frame (h0=0.5, q0=0.5) and therefore cannot be an ordinary galaxy. It shows no radio emission (the 3 sigma upper limit of its flux at 6 cm is 60 µJy), indicating a radio-to-optical flux ratio at least as small as that of the radio-weakest BL Lacertae objects known. It is also not linearly polarized to a 3 sigma upper limit of 4% in the observed I band. Therefore, it is either the most distant BL Lac object known to date, with very weak radio emission, or a new type of unbeamed quasar, whose broad emission line region is very weak or absent.

Regional Solutions for Regional Problems: East Timor and Solomon Islands

Science.gov (United States)

2012-03-21

perceived Australia in this light and were openly opposed to Australian leadership of the multi- national mission. Prime Minister Mahathir bin Mohamad of...such as Malaysia’s Prime Minister Mahathir , expressed concern over Australia’s forceful responses, regional leaders were broadly supportive and

Widespread epigenetic abnormalities suggest a broad DNA methylation erasure defect in abnormal human sperm.

Directory of Open Access Journals (Sweden)

Sahar Houshdaran

2007-12-01

Full Text Available Male-factor infertility is a common condition, and etiology is unknown for a high proportion of cases. Abnormal epigenetic programming of the germline is proposed as a possible mechanism compromising spermatogenesis of some men currently diagnosed with idiopathic infertility. During germ cell maturation and gametogenesis, cells of the germ line undergo extensive epigenetic reprogramming. This process involves widespread erasure of somatic-like patterns of DNA methylation followed by establishment of sex-specific patterns by de novo DNA methylation. Incomplete reprogramming of the male germ line could, in theory, result in both altered sperm DNA methylation and compromised spermatogenesis.We determined concentration, motility and morphology of sperm in semen samples collected by male members of couples attending an infertility clinic. Using MethyLight and Illumina assays we measured methylation of DNA isolated from purified sperm from the same samples. Methylation at numerous sequences was elevated in DNA from poor quality sperm.This is the first report of a broad epigenetic defect associated with abnormal semen parameters. Our results suggest that the underlying mechanism for these epigenetic changes may be improper erasure of DNA methylation during epigenetic reprogramming of the male germ line.

Design of the Yang magnetically-insulated transmission line

International Nuclear Information System (INIS)

Gu Yuanchao; Song Shenyi

2002-01-01

The authors have designed a new magnetically insulated transmission line (MITL) for the Yang accelerator. The differences between the existing line and the designing one are given. The electric strength of some special regions on the lines and the inductance of the lines have been calculated. The authors have checked the states of magnetic insulation on the designing line

Investigating the Effect of Cultivate Lines Direction, Bio-Fertilizer Nitroxin and Superabsorbent Materials on Yield and Yield Components of Broad Leaf Vetch (Vicia narbonensis

Directory of Open Access Journals (Sweden)

E Latifinia

2017-12-01

Full Text Available Introduction The excessive use of fertilizers has caused severe damages to the bio-cycle in the fields and has destroyed the sustainable agricultural machinery. These destructive effects have led to the recommended use of bio-fertilizers. Biodiversity is one of the key sources of supplying nutrients in sustainable agriculture. The use of biological fertilizers in a sustainable agricultural system leads to sustained yield in plant production. Biological fertilizer of nitroxin has increased biological yield and grain yield in fodder corn. Water shortage as a limiting factor has limited vegetation growth and development in these areas. Considering that Iran is a dry country, the use of super adsorbent is one of the ways to reduce water consumption. Investigators in the study of superabsorbent showed that superabsorbent had a significant and positive effect on the yield of forage plants. Crop directions can affect the amount of the product by increasing the leaf area and absorbing light. Proper orientation of crop lines increases the photosynthetic efficiency and increases the yield and yield components of the plant. Research has shown that yields are much higher in plants planted on the north-south lines compared with plants planted on east-west lines. Materials and Methods In order to investigate the effect of nitroxin and superabsorbent fertilizer on yield and yield components of broad leaf vetch in a research field of agricultural faculty, Lorestan University, as a split plot factorial based on a complete block design randomization was performed in three replicates. In this research, for main lines, the main factors were considered in the North-South and East-West directions in the main plots. Sub-factors In this experiment, nitroxin biosynthesis and superabsorbent materials were applied at two levels of consumption and non-consumption in sub plots. Nitroxin fertilizer was used as a seed lot at a rate of 1 liter per hectare and the stockosorb

Experimental verification of the line-shape distortion in resonance Auger spectra

International Nuclear Information System (INIS)

Aksela, S.; Kukk, E.; Aksela, H.; Svensson, S.

1995-01-01

When the mean excitation energy and the width of a broad photon band are varied the Kr 3d 5/2 -1 5p→4p -2 5p resonance Auger electron lines show strong asymmetry and their average kinetic energies shift. Even extra peaks appear. Our results demonstrate experimentally, for the first time, that the incident photon energy distribution has very crucial importance on the resonance Auger line shape and thus on the reliable data analysis of complicated Auger spectra

Broad target cell selectivity of Kaposi's sarcoma-associated herpesvirus glycoprotein-mediated cell fusion and virion entry

International Nuclear Information System (INIS)

Kaleeba, Johnan A.R.; Berger, Edward A.

2006-01-01

The molecular mechanism of Kaposi's sarcoma-associated herpesvirus (KSHV, human herpesvirus 8) entry is poorly understood. We tested a broad variety of cell types of diverse species and tissue origin for their ability to function as targets in a quantitative reporter gene assay for KSHV-glycoprotein-mediated cell fusion. Several human, non-human primate, and rabbit cell lines were efficient targets, whereas rodent and all human lymphoblastoid cell lines were weak targets. Parallel findings were obtained with a virion entry assay using a recombinant KSHV encoding a reporter gene. No correlation was observed between target cell activity and surface expression of α3β1 integrin, a proposed KSHV receptor. We hypothesize that target cell permissiveness in both the cell fusion and virion entry assays reflects the presence of a putative KSHV fusion-entry receptor

Embedded star formation in the extended narrow line region of Centaurus A: Extreme mixing observed by MUSE

Science.gov (United States)

Santoro, F.; Oonk, J. B. R.; Morganti, R.; Oosterloo, T. A.; Tadhunter, C.

2016-05-01

We present a detailed study of the complex ionization structure in a small (~250 pc) extended narrow line region (ENLR) cloud near Centaurus A using the Multi Unit Spectroscopic Explorer. This cloud is located in the so-called outer filament of ionized gas (about 15 kpc from the nucleus) where jet-induced star formation has been suggested to occur by different studies. We find that, despite the small size, a mixture of ionization mechanisms is operating, resulting in considerable complexity in the spatial ionization structure. The area includes two H II regions where star formation is occurring and another location where star formation must have ceased very recently. Interestingly, the extreme Balmer decrement of one of the star forming regions (Hα/Hβobs ~ 6) indicates that it is still heavily embedded in its natal cocoon of gas and dust. At all three locations a continuum counterpart is found with spectra matching those of O/B stars local to Centaurus A. The H II regions are embedded in a larger gas complex which is photoionized by the radiation of the central active galactic nucleus (AGN), but the O/B stars affect the spatial ionization pattern in the ENLR cloud very locally. In particular, in the surroundings of the youngest star forming region, we can isolate a tight mixing sequence in the diagnostic diagram going from gas with ionization due to a pure stellar continuum to gas only photoionized by the AGN. These results emphasize the complexity and the mixture of processes occurring in star forming regions under the influence of an AGN radiation. This is relevant for our understanding of AGN-induced star formation suggested to occur in a number of objects, including this region of Centaurus A. They also illustrate that these young stars influence the gas over only a limited region.

Broad-beam, high current, metal ion implantation facility

International Nuclear Information System (INIS)

Brown, I.G.; Dickinson, M.R.; Galvin, J.E.; Godechot, X.; MacGill, R.A.

1990-07-01

We have developed a high current metal ion implantation facility with which high current beams of virtually all the solid metals of the Periodic Table can be produced. The facility makes use of a metal vapor vacuum arc ion source which is operated in a pulsed mode, with pulse width 0.25 ms and repetition rate up to 100 pps. Beam extraction voltage is up to 100 kV, corresponding to an ion energy of up to several hundred keV because of the ion charge state multiplicity; beam current is up to several Amperes peak and around 10 mA time averaged delivered onto target. Implantation is done in a broad-beam mode, with a direct line-of-sight from ion source to target. Here we describe the facility and some of the implants that have been carried out using it, including the 'seeding' of silicon wafers prior to CVD with titanium, palladium or tungsten, the formation of buried iridium silicide layers, and actinide (uranium and thorium) doping of III-V compounds. 16 refs., 6 figs

Broad Frequency LTCC Vertical Interconnect Transition for Multichip Modules and System on Package Applications

Science.gov (United States)

Decrossas, Emmanuel; Glover, Michael D.; Porter, Kaoru; Cannon, Tom; Mantooth, H. Alan; Hamilton, M. C.

2013-01-01

Various stripline structures and flip chip interconnect designs for high-speed digital communication systems implemented in low temperature co-fired ceramic (LTCC) substrates are studied in this paper. Specifically, two different transition designs from edge launch 2.4 millimeter connectors to stripline transmission lines embedded in LTCC are discussed. After characterizing the DuPont (sup trademark) 9K7 green tape, different designs are proposed to improve signal integrity for high-speed digital data. The full-wave simulations and experimental data validate the presented designs over a broad frequency band from Direct Current to 50 gigahertz and beyond.

High-resolution continuum source electrothermal atomic absorption spectrometry: Linearization of the calibration curves within a broad concentration range

Energy Technology Data Exchange (ETDEWEB)

Katskov, Dmitri, E-mail: katskovda@tut.ac.za [Tshwane University of Technology, Chemistry Department, Pretoria 0001 (South Africa); Hlongwane, Miranda [Tshwane University of Technology, Chemistry Department, Pretoria 0001 (South Africa); Heitmann, Uwe [German Aerospace Center, Rose-Luxemburg Str. 2, 10178 Berlin (Germany); Florek, Stefan [ISAS-Leibniz-Institut fuer Analytische Wissenschaften e.V., Albert-Einstein-Str. 9,12489 Berlin (Germany)

2012-05-15

The calculation algorithm suggested provides linearization of the calibration curves in high-resolution continuum source electrothermal atomic absorption spectrometry. The algorithm is based on the modification of the function wavelength-integrated absorbance vs. concentration of analyte vapor in the absorption volume. According to the suggested approach, the absorption line is represented by a triangle for low and trapezium for high analyte vapor concentration in the absorption volume. The respective semi-empirical formulas include two linearization parameters, which depend on properties of the absorption line and characteristics of the atomizer and spectrometer. The parameters can be approximately evaluated from the theory and determined in practice from the original broad-range calibration curve. The parameters were found and the proposed calculation algorithm verified in the experiments on direct determination of Ag, Cd, Cu, Fe, Mn and Pb in the solutions within a concentration ranges from 0.15 to 625 {mu}g{center_dot}L{sup -1} using tube, platform tube and filter furnace atomizers. The use of various atomizers, lines, elements and atomization temperatures made possible the simulation of various practical analytical conditions. It was found that the algorithm and optimal linearization parameters made it possible to obtain for each line and atomizer linear approximations of the calibration curves within 3-4 orders of magnitude with correlation coefficients close to 0.999. The algorithm makes possible to employ a single line for the direct element determination over a broad concentration range. The sources of errors and the possibility of a priori theoretical evaluation of the linearization parameters are discussed. - Highlights: Black-Right-Pointing-Pointer New calculation algorithm for HR-CS ET AAS measurements was proposed and applied. Black-Right-Pointing-Pointer The suggested formulas include two parameters to be determined experimentally. Black

Polarization of Coronal Forbidden Lines

Energy Technology Data Exchange (ETDEWEB)

Li, Hao; Qu, Zhongquan [Yunnan Observatories, Chinese Academy of Sciences, Kunming, Yunnan 650011 (China); Landi Degl’Innocenti, Egidio, E-mail: sayahoro@ynao.ac.cn [Dipartimento di Astronomia e Scienza dello Spazio, Università di Firenze, Largo E. Fermi 2, I-50125 Firenze (Italy)

2017-03-20

Since the magnetic field is responsible for most manifestations of solar activity, one of the most challenging problems in solar physics is the diagnostics of solar magnetic fields, particularly in the outer atmosphere. To this end, it is important to develop rigorous diagnostic tools to interpret polarimetric observations in suitable spectral lines. This paper is devoted to analyzing the diagnostic content of linear polarization imaging observations in coronal forbidden lines. Although this technique is restricted to off-limb observations, it represents a significant tool to diagnose the magnetic field structure in the solar corona, where the magnetic field is intrinsically weak and still poorly known. We adopt the quantum theory of polarized line formation developed in the framework of the density matrix formalism, and synthesize images of the emergent linear polarization signal in coronal forbidden lines using potential-field source-surface magnetic field models. The influence of electronic collisions, active regions, and Thomson scattering on the linear polarization of coronal forbidden lines is also examined. It is found that active regions and Thomson scattering are capable of conspicuously influencing the orientation of the linear polarization. These effects have to be carefully taken into account to increase the accuracy of the field diagnostics. We also found that linear polarization observation in suitable lines can give valuable information on the long-term evolution of the magnetic field in the solar corona.

Determining the Pressure Shift of Helium I Lines Using White Dwarf Stars

Science.gov (United States)

Camarota, Lawrence

This dissertation explores the non-Doppler shifting of Helium lines in the high pressure conditions of a white dwarf photosphere. In particular, this dissertation seeks to mathematically quantify the shift in a way that is simple to reproduce and account for in future studies without requiring prior knowledge of the star's bulk properties (mass, radius, temperature, etc.). Two main methods will be used in this analysis. First, the spectral line will be quantified with a continuous wavelet transformation, and the components will be used in a chi2 minimizing linear regression to predict the shift. Second, the position of the lines will be calculated using a best-fit Levy-alpha line function. These techniques stand in contrast to traditional methods of quantifying the center of often broad spectral lines, which usually assume symmetry on the parts of the lines.

The structure of the broad-line region in active galactic nuclei. I. Reconstructed velocity-delay maps

DEFF Research Database (Denmark)

Grier, C.J.; Peterson, B.M.; Pogge, R.W.

2013-01-01

We present velocity-resolved reverberation results for five active galactic nuclei. We recovered velocity-delay maps using the maximum entropy method for four objects: Mrk 335, Mrk 1501, 3C 120, and PG 2130+099. For the fifth, Mrk 6, we were only able to measure mean time delays in different velo...

Specific degradation of 3[prime prime or minute] regions of GUS mRNA in posttranscriptionally silenced tobacco lines may be related to 5[prime prime or minute]-3[prime prime or minute] spreading of silencing

DEFF Research Database (Denmark)

Braunstein, T.H.; Moury, B.; Johannessen, M.M.

2002-01-01

background, we have performed detailed analyses of target regions in three spontaneously beta-glucuronidase (GUS) silencing tobacco lines of different origin. From quantitative cosuppression experiments, we show that the main target region in all three tobacco lines is found within the 3' half of the GUS...... VIGS. Surprisingly, only evidence for spreading of the target region in the 5'-3' direction was obtained. This finding may help explain why the majority of target regions examined to date lie within the 3' region of transgenes....

What's in the Wind? Determining the Properties of Outflowing Gas in Powerful Broad Absorption Line Quasars

Science.gov (United States)

Leighly, Karen

2017-08-01

A significant fraction of quasars exhibits blueshifted broadabsorption lines (BALs) in their rest-UV spectra, indicating powerfuloutflows emerging from the central engine. These outflows may removeangular momentum to enable black hole growth, enrich the intergalacticmedium with metals, and trigger quenching of star formation ingalaxies. Despite years of study, the physical conditions of theoutflowing gas are poorly understood. The handful of objects that havebeen subjected to detailed analysis are atypical and characterized byrelatively narrow lines where blending is unimportant. However,investigating more powerful BAL quasars will give us better insightinto the types of outflows much more likely to impact galaxyevolution.SimBAL is a novel spectral synthesis fitting method for BAL quasarsthat uses Bayesian model calibration to compare synthetic to observedspectra. With the model inputs of ionization parameter, columndensity, and covering fraction specified, the gas properties givingrise to the BAL features can be determined. We propose to applySimBAL to archival spectra of a sample of 14 luminous BAL quasars to characterize their bulk outflow properties as a function of velocityfor the first time. Our results will show the range of parameterstypical of powerful outflows, an essential step towards constrainingthe physics behind quasar winds and thus their impact on theirenvironments.

Demonstration of a Reduced Boil-Off Dewar with Broad Area Cooling

Science.gov (United States)

Gully, W. J.; Glaister, D.; Mills, G. L.

2010-04-01

Pumped helium circulation loops are an efficient and reliable way of transferring heat from a cooled device to a cryocooler. Such loops have been proposed for cooling IR detectors and their associated optics. A Broad Area Cooling (BAC) concept, in which a helium circulation loop is used to transfer heat from a dewar shield to a cryocooler has been proposed[1]. Ball has built a novel system that uses the Stirling refrigerator's compressor to drive the circulating flow by means of valves in its transfer line, eliminating the need for a separate circulation pump. The BAC system will be described and subsystem test results will be presented. An upcoming test, in which the cryocooler will be used to cool a shield in a special test dewar[2], will be discussed.

Artificial light at night confounds broad-scale habitat use by migrating birds

Science.gov (United States)

McLaren, James D.; Buler, Jeffrey J.; Schreckengost, Tim; Smolinsky, Jaclyn A.; Boone, Matthew; van Loon, E. Emiel; Dawson, Deanna K.; Walters, Eric L.

2018-01-01

With many of the world's migratory bird populations in alarming decline, broad-scale assessments of responses to migratory hazards may prove crucial to successful conservation efforts. Most birds migrate at night through increasingly light-polluted skies. Bright light sources can attract airborne migrants and lead to collisions with structures, but might also influence selection of migratory stopover habitat and thereby acquisition of food resources. We demonstrate, using multi-year weather radar measurements of nocturnal migrants across the northeastern U.S., that autumnal migrant stopover density increased at regional scales with proximity to the brightest areas, but decreased within a few kilometers of brightly-lit sources. This finding implies broad-scale attraction to artificial light while airborne, impeding selection for extensive forest habitat. Given that high-quality stopover habitat is critical to successful migration, and hindrances during migration can decrease fitness, artificial lights present a potentially heightened conservation concern for migratory bird populations.

Nasca Lines, Peru

Science.gov (United States)

2001-01-01

The Nasca Lines are located in the Pampa region of Peru, the desolate plain of the Peruvian coast 400 km south of Lima. The Lines were first spotted when commercial airlines began flying across the Peruvian desert in the 1920's. Passengers reported seeing 'primitive landing strips' on the ground below. The Lines were made by removing the iron-oxide coated pebbles which cover the surface of the desert. When the gravel is removed, they contrast with the light color underneath. In this way the lines were drawn as furrows of a lighter color. On the pampa, south of the Nasca Lines, archaeologists have now uncovered the lost city of the line-builders, Cahuachi. It was built nearly two thousand years ago and was mysteriously abandoned 500 years later. This ASTER sub-image covers an area of 14 x 18 km, was acquired on December 22, 2000, and is located at 14.7 degrees south latitude and 75.1 degrees west longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

Procedure for analyzing the x-ray line profiles of disordered carbons

International Nuclear Information System (INIS)

Henry, L.G.; Bragg, R.H.; Bose, S.

1981-12-01

A systematic procedure to correct for various distortions in the broad x-ray line profiles of glass-like carbons (GC) is described. The profile is first corrected for distortions due to low specimen absorption, secondly for incoherent (Compton) scattering, and then strong small angle scattering. The resulting profile is then multiplied by the appropriate trigonometric (Lorentz and polarization) factors. Finally, correction is made for the variation of the atomic scattering factor across the broad peaks. Two examples of the GC heat treatment at 1000 0 C and 2700 0 C have been used to illustrate the outcome of the corrections. 8 figures

77 FR 665 - Endangered and Threatened Wildlife and Plants; Listing Two Distinct Population Segments of Broad...

Science.gov (United States)

2012-01-05

... threat to the broad-snouted caiman, what regional climate change models are available, and whether they are reliable and credible to use as a step-down model for assessing the effects of climate change on... waterways, including rivers near waterfalls such as Iguaz[uacute], and freshwater creeks with rocky bottoms...

Molecular evolution of broadly neutralizing Llama antibodies to the CD4-binding site of HIV-1.

Science.gov (United States)

McCoy, Laura E; Rutten, Lucy; Frampton, Dan; Anderson, Ian; Granger, Luke; Bashford-Rogers, Rachael; Dekkers, Gillian; Strokappe, Nika M; Seaman, Michael S; Koh, Willie; Grippo, Vanina; Kliche, Alexander; Verrips, Theo; Kellam, Paul; Fassati, Ariberto; Weiss, Robin A

2014-12-01

To date, no immunization of humans or animals has elicited broadly neutralizing sera able to prevent HIV-1 transmission; however, elicitation of broad and potent heavy chain only antibodies (HCAb) has previously been reported in llamas. In this study, the anti-HIV immune responses in immunized llamas were studied via deep sequencing analysis using broadly neutralizing monoclonal HCAbs as a guides. Distinct neutralizing antibody lineages were identified in each animal, including two defined by novel antibodies (as variable regions called VHH) identified by robotic screening of over 6000 clones. The combined application of five VHH against viruses from clades A, B, C and CRF_AG resulted in neutralization as potent as any of the VHH individually and a predicted 100% coverage with a median IC50 of 0.17 µg/ml for the panel of 60 viruses tested. Molecular analysis of the VHH repertoires of two sets of immunized animals showed that each neutralizing lineage was only observed following immunization, demonstrating that they were elicited de novo. Our results show that immunization can induce potent and broadly neutralizing antibodies in llamas with features similar to human antibodies and provide a framework to analyze the effectiveness of immunization protocols.

Iron forbidden lines in tokamak discharges

International Nuclear Information System (INIS)

Suckewer, S.; Hinnov, E.

1979-03-01

Several spectrum lines from forbidden transitions in the ground configurations of highly ionized atoms have been observed in the PLT tokamak discharges. Such lines allow localized observations, in the high-temperature regions of the plasma, of ion-temperatures, plasma motions, and spatial distributions of ions. Measured absolute intensities of the forbidden lines have been compared with simultaneous observations of the ion resonance lines and with model calculations in order to deduce the mechanism of level populaions by means of electron collisions and radiative transitions

Iron forbidden lines in tokamak discharges

Energy Technology Data Exchange (ETDEWEB)

Suckewer, S.; Hinnov, E.

1979-03-01

Several spectrum lines from forbidden transitions in the ground configurations of highly ionized atoms have been observed in the PLT tokamak discharges. Such lines allow localized observations, in the high-temperature regions of the plasma, of ion-temperatures, plasma motions, and spatial distributions of ions. Measured absolute intensities of the forbidden lines have been compared with simultaneous observations of the ion resonance lines and with model calculations in order to deduce the mechanism of level populaions by means of electron collisions and radiative transitions.

UV line emission of symbiotic stars

International Nuclear Information System (INIS)

Nussbaumer, H.

1982-01-01

General characteristics of emission line spectra from symbiotic stars are outlined. Data from some special line ratios in the 1000 A - 3000 A range, and others connecting the visual and the far UV lines are presented, and their application to symbiotic stars is discussed. Integrated fractional abundances for ions easily observed in the far UV are given to facilitate abundance determinations for nebular conditions. It is found that the physical conditions of the regions emitting the emission line spectra differ considerably among different symbiotic stars. (Auth.)

A SAMPLE OF SEYFERT-2 GALAXIES WITH ULTRALUMINOUS GALAXY-WIDE NARROW-LINE REGIONS: QUASAR LIGHT ECHOES?

International Nuclear Information System (INIS)

Schirmer, M.; Diaz, R.; Levenson, N. A.; Winge, C.; Holhjem, K.

2013-01-01

We report the discovery of Seyfert-2 galaxies in SDSS-DR8 with galaxy-wide, ultraluminous narrow-line regions (NLRs) at redshifts z = 0.2-0.6. With a space density of 4.4 Gpc –3 at z ∼ 0.3, these 'green beans' (GBs) are amongst the rarest objects in the universe. We are witnessing an exceptional and/or short-lived phenomenon in the life cycle of active galactic nuclei (AGNs). The main focus of this paper is on a detailed analysis of the GB prototype galaxy J2240–0927 (z = 0.326). Its NLR extends over 26 × 44 kpc and is surrounded by an extended NLR. With a total [O III] λ5008 luminosity of (5.7 ± 0.9) × 10 43 erg s –1 , this is one of the most luminous NLRs known around any type-2 galaxy. Using VLT/XSHOOTER, we show that the NLR is powered by an AGN, and we derive resolved extinction, density, and ionization maps. Gas kinematics is disturbed on a global scale, and high-velocity outflows are absent or faint. This NLR is unlike any other NLR or extended emission line region known. Spectroscopy with Gemini/GMOS reveals extended, high-luminosity [O III] emission also in other GBs. WISE 24 μm luminosities are 5-50 times lower than predicted by the [O III] fluxes, suggesting that the NLRs reflect earlier, very active quasar states that have strongly subsided in less than a galaxy's light-crossing time. These light echoes, or ionization echoes, are about 100 times more luminous than any other such echo known to date. X-ray data are needed for photoionization modeling and to verify the light echoes.

Shallow Drilling In The Salton Sea Region, The Thermal Anomaly

Energy Technology Data Exchange (ETDEWEB)

Newmark, R. L.; Kasameyer, P. W.; Younker, L. W.

1987-01-01

During two shallow thermal drilling programs, thermal measurements were obtained in 56 shallow (76.2 m) and one intermediate (457.3 m) depth holes located both onshore and offshore along the southern margin of the Salton Sea in the Imperial Valley, California. These data complete the surficial coverage of the thermal anomaly, revealing the shape and lateral extent of the hydrothermal system. The thermal data show the region of high thermal gradients to extend only a short distance offshore to the north of the Quaternary volcanic domes which are exposed along the southern shore of the Salton Sea. The thermal anomaly has an arcuate shape, about 4 km wide and 12 km long. Across the center of the anomaly, the transition zone between locations exhibiting high thermal gradients and those exhibiting regional thermal gradients is quite narrow. Thermal gradients rise from near regional (0.09 C/m) to extreme (0.83 C/m) in only 2.4 km. The heat flow in the central part of the anomaly is >600 mW/m{sup 2} and in some areas exceeds 1200 mW/m{sup 2}. The shape of the thermal anomaly is asymmetric with respect to the line of volcanoes previously thought to represent the center of the field, with its center line offset south of the volcanic buttes. There is no broad thermal anomaly associated with the magnetic high that extends offshore to the northeast from the volcanic domes. These observations of the thermal anomaly provide important constraints for models of the circulation of the hydrothermal system. Thermal budgets based on a simple model for this hydrothermal system indicate that the heat influx rate for local ''hot spots'' in the region may be large enough to account for the rate of heat flux from the entire Salton Trough.

Financial viability of the Sonora-Baja California interconnection line

International Nuclear Information System (INIS)

Alonso, G.; Ortega, G.

2017-09-01

In the Development Program of the National Electricity Sector 2015-2029, an electric interconnection line between Sonora and Baja California (Mexico) is proposed, this study analyzes the financial viability of this interconnection line based on the maximum hourly and seasonal energy demand between both regions and proposes alternatives for the supply of electric power that supports the economic convenience of this interconnection line. The results show that additional capacity is required in Sonora to cover the maximum demands of both regions since in the current condition of the National Electric System the interconnection line is not justified. (Author)

FAR-INFRARED LINE SPECTRA OF SEYFERT GALAXIES FROM THE HERSCHEL-PACS SPECTROMETER

International Nuclear Information System (INIS)

Spinoglio, Luigi; Pereira-Santaella, Miguel; Busquet, Gemma; Dasyra, Kalliopi M.; Calzoletti, Luca; Malkan, Matthew A.; Tommasin, Silvia

2015-01-01

We observed the far-IR fine-structure lines of 26 Seyfert galaxies with the Herschel-PACS spectrometer. These observations are complemented with Spitzer Infrared Spectrograph and Herschel SPIRE spectroscopy. We used the ionic lines to determine electron densities in the ionized gas and the [C I] lines, observed with SPIRE, to measure the neutral gas densities, while the [O I] lines measure the gas temperature, at densities below ∼10 4  cm –3 . Using the [O I]145 μm/63 μm and [S III]33/18 μm line ratios, we find an anti-correlation of the temperature with the gas density. Various fine-structure line ratios show density stratifications in these active galaxies. On average, electron densities increase with the ionization potential of the ions. The infrared lines arise partly in the narrow line region, photoionized by the active galactic nucleus (AGN), partly in H II regions photoionized by hot stars, and partly in photo-dissociated regions. We attempt to separate the contributions to the line emission produced in these different regions by comparing our observed emission line ratios to theoretical values. In particular, we tried to separate the contribution of AGNs and star formation by using a combination of Spitzer and Herschel lines, and we found that besides the well-known mid-IR line ratios, the line ratio of [O III]88 μm/[O IV]26 μm can reliably discriminate the two emission regions, while the far-IR line ratio of [C II]157 μm/[O I]63 μm is only able to mildly separate the two regimes. By comparing the observed [C II]157 μm/[N II]205 μm ratio with photoionization models, we also found that most of the [C II] emission in the galaxies we examined is due to photodissociation regions

FAR-INFRARED LINE SPECTRA OF SEYFERT GALAXIES FROM THE HERSCHEL-PACS SPECTROMETER

Energy Technology Data Exchange (ETDEWEB)

Spinoglio, Luigi; Pereira-Santaella, Miguel; Busquet, Gemma [Istituto di Astrofisica e Planetologia Spaziali, INAF, Via Fosso del Cavaliere 100, I-00133 Roma (Italy); Dasyra, Kalliopi M. [Observatoire de Paris, LERMA (CNRS:UMR8112), 61 Av. de l' Observatoire, F-75014, Paris (France); Calzoletti, Luca [Agenzia Spaziale Italiana (ASI) Science Data Center, I-00044 Frascati (Roma) (Italy); Malkan, Matthew A. [Astronomy Division, University of California, Los Angeles, CA 90095-1547 (United States); Tommasin, Silvia, E-mail: luigi.spinoglio@iaps.inaf.it [Weizmann Institute of Science, Department of Neurobiology, Rehovot 76100 (Israel)

2015-01-20

We observed the far-IR fine-structure lines of 26 Seyfert galaxies with the Herschel-PACS spectrometer. These observations are complemented with Spitzer Infrared Spectrograph and Herschel SPIRE spectroscopy. We used the ionic lines to determine electron densities in the ionized gas and the [C I] lines, observed with SPIRE, to measure the neutral gas densities, while the [O I] lines measure the gas temperature, at densities below ∼10{sup 4} cm{sup –3}. Using the [O I]145 μm/63 μm and [S III]33/18 μm line ratios, we find an anti-correlation of the temperature with the gas density. Various fine-structure line ratios show density stratifications in these active galaxies. On average, electron densities increase with the ionization potential of the ions. The infrared lines arise partly in the narrow line region, photoionized by the active galactic nucleus (AGN), partly in H II regions photoionized by hot stars, and partly in photo-dissociated regions. We attempt to separate the contributions to the line emission produced in these different regions by comparing our observed emission line ratios to theoretical values. In particular, we tried to separate the contribution of AGNs and star formation by using a combination of Spitzer and Herschel lines, and we found that besides the well-known mid-IR line ratios, the line ratio of [O III]88 μm/[O IV]26 μm can reliably discriminate the two emission regions, while the far-IR line ratio of [C II]157 μm/[O I]63 μm is only able to mildly separate the two regimes. By comparing the observed [C II]157 μm/[N II]205 μm ratio with photoionization models, we also found that most of the [C II] emission in the galaxies we examined is due to photodissociation regions.

Validation, automatic generation and use of broad phonetic transcriptions

NARCIS (Netherlands)

Bael, Cristophe Patrick Jan Van

2007-01-01

Broad phonetic transcriptions represent the pronunciation of words as strings of characters from specifically designed symbol sets. In everyday life, broad phonetic transcriptions are often used as aids to pronounce (foreign) words. In addition, broad phonetic transcriptions are often used for

Integral Field Spectroscopy of the Extended Emission-Line Region of 4C 37.43

Science.gov (United States)

Fu, Hai; Stockton, Alan

2007-09-01

We present Gemini integral field spectroscopy and Keck II long-slit spectroscopy of the extended emission-line region (EELR) around the quasar 4C 37.43. The velocity structure of the ionized gas is complex and cannot be explained globally by a simple dynamical model. The spectra from the clouds are inconsistent with shock or ``shock + precursor'' ionization models, but they are consistent with photoionization by the quasar nucleus. The best-fit photoionization model requires a low-metallicity [12+log(O/H)Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina). Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the financial support of the W. M. Keck Foundation.

Regional Transmission Projects: Finding Solutions

Energy Technology Data Exchange (ETDEWEB)

The Keystone Center

2005-06-15

The Keystone Center convened and facilitated a year-long Dialogue on "Regional Transmission Projects: Finding Solutions" to develop recommendations that will help address the difficult and contentious issues related to expansions of regional electric transmission systems that are needed for reliable and economic transmission of power within and across regions. This effort brought together a cross-section of affected stakeholders and thought leaders to address the problem with the collective wisdom of their experience and interests. Transmission owners sat at the table with consumer advocates and environmental organizations. Representatives from regional transmission organizations exchanged ideas with state and federal regulators. Generation developers explored common interests with public power suppliers. Together, the Dialogue participants developed consensus solutions about how to begin unraveling some of the more intractable issues surrounding identification of need, allocation of costs, and reaching consensus on siting issues that can frustrate the development of regional transmission infrastructure. The recommendations fall into three broad categories: 1. Recommendations on appropriate institutional arrangements and processes for achieving regional consensus on the need for new or expanded transmission infrastructure 2. Recommendations on the process for siting of transmission lines 3. Recommendations on the tools needed to support regional planning, cost allocation, and siting efforts. List of Dialogue participants: List of Dialogue Participants: American Electric Power American Transmission Company American Wind Energy Association California ISO Calpine Corporation Cinergy Edison Electric Institute Environmental Defense Federal Energy Regulatory Commission Great River Energy International Transmission Company ISO-New England Iowa Public Utility Board Kanner & Associates Midwest ISO National Association of Regulatory Utility Commissioners National Association

Profiles of the N II 6584 A line over the giant H II regions IC 1318b and c, NGC 7000 and IC 5070. 2

Energy Technology Data Exchange (ETDEWEB)

Canto, J; Johnson, P G; Meaburn, J; Mikhail, J S; Terrett, D L; White, N J [Manchester Univ. (UK). Dept of Astronomy

1979-06-01

Previously (Paper I) large-scale splitting of the (N II) line was discovered over an area of IC 1318b. The motions of the ionized material have now been mapped over a much larger region of this nebula and also IC 1318c. The splitting reaches a maximum value of 53 km/s over the faintest regions of IC 1318b and occurs over an area approximately > 20 pc across. However, few split (N II) lines were found over IC 1318c, but the motions of this whole ionized and neutral complex have been shown to be closely related. Wind-driven flows along neutral and ionized shells are proposed to explain the observations. Similar measurements have also been made on either side of the dark lane separating NGC 7000 from IC 5070.

Photon-dominated region modeling of the [C I], [C II], and CO Line Emission From A Boundary In The Taurus molecular cloud

Energy Technology Data Exchange (ETDEWEB)

Orr, Matthew E. [Physics and Astronomy Department, University of Southern California, Los Angeles, CA 90089 (United States); Pineda, Jorge L.; Goldsmith, Paul F. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099 (United States)

2014-11-01

We present [C I] and [C II] observations of a linear edge region in the Taurus molecular cloud, and model this region as a cylindrically symmetric photon-dominated region (PDR) exposed to a low-intensity UV radiation field. The sharp, long profile of the linear edge makes it an ideal case to test PDR models and determine cloud parameters. We compare observations of the [C I], {sup 3} P {sub 1} → {sup 3} P {sub 0} (492 GHz), [C I] {sup 3} P {sub 2} → {sup 3} P {sub 1} (809 GHz), and [C II] {sup 2} P {sub 3/2} → {sup 2} P {sub 1/2} (1900 GHz) transitions, as well as the lowest rotational transitions of {sup 12}CO and {sup 13}CO, with line intensities produced by the RATRAN radiative transfer code from the results of the Meudon PDR code. We constrain the density structure of the cloud by fitting a cylindrical density function to visual extinction data. We study the effects of variation of the FUV field, {sup 12}C/{sup 13}C isotopic abundance ratio, sulfur depletion, cosmic ray ionization rate, and inclination of the filament relative to the sky-plane on the chemical network of the PDR model and resulting line emission. We also consider the role of suprathermal chemistry and density inhomogeneities. We find good agreement between the model and observations, and that the integrated line intensities can be explained by a PDR model with an external FUV field of 0.05 G {sub 0}, a low ratio of {sup 12}C to {sup 13}C ∼43, a highly depleted sulfur abundance (by a factor of at least 50), a cosmic ray ionization rate (3-6) × 10{sup –17} s{sup –1}, and without significant effects from inclination, clumping or suprathermal chemistry.

Subwavelength grating enabled on-chip ultra-compact optical true time delay line.

Science.gov (United States)

Wang, Junjia; Ashrafi, Reza; Adams, Rhys; Glesk, Ivan; Gasulla, Ivana; Capmany, José; Chen, Lawrence R

2016-07-26

An optical true time delay line (OTTDL) is a basic photonic building block that enables many microwave photonic and optical processing operations. The conventional design for an integrated OTTDL that is based on spatial diversity uses a length-variable waveguide array to create the optical time delays, which can introduce complexities in the integrated circuit design. Here we report the first ever demonstration of an integrated index-variable OTTDL that exploits spatial diversity in an equal length waveguide array. The approach uses subwavelength grating waveguides in silicon-on-insulator (SOI), which enables the realization of OTTDLs having a simple geometry and that occupy a compact chip area. Moreover, compared to conventional wavelength-variable delay lines with a few THz operation bandwidth, our index-variable OTTDL has an extremely broad operation bandwidth practically exceeding several tens of THz, which supports operation for various input optical signals with broad ranges of central wavelength and bandwidth.

Numerical study of whisker field lines in the periphery of the Large Helical Device

International Nuclear Information System (INIS)

Akao, Hideki

1990-01-01

The behavior of periphery magnetic field lines in the standard Large-Helical Device (l=2 heliotron/torsatron type) configuration is studied numerically. Three different types of behavior are found, corresponding to three different regions: the stochastic region near the outermost magnetic surface, the whisker region, and the inter-whisker region outside the stochastic region. The behavior of whisker and inter-whisker field lines is specifically analyzed. It is found that whisker field lines exhibit both regular and irregular types of behavior, whereas inter-whisker field lines exhibit only regular behavior. The connection lengths for the whisker field lines are usually as long as several tens of toroidal pitches, whereas those for the inter-whisker field lines are usually less than ten toroidal pitch lengths. Whisker field lines are characterized by three fundamental processes; stretching, folding, and nesting associated with the motion of a residual X-point of the separatrix. Simple modeling is performed to reproduce these three fundamental processes. (author)

NuSTAR discovery of a cyclotron line in KS 1947+300

DEFF Research Database (Denmark)

Fürst, Felix; Pottschmidt, Katja; Wilms, Jörn

2014-01-01

-resolved spectroscopy reveals that the strength of the feature changes strongly with pulse phase and is most prominent during the broad minimum of the pulse profile. At the same phases the line also becomes visible in the first and third observation at the same energy. This discovery implies that KS 1947+300 has...

Quasars, Seyfert galaxies and active galactic nuclei

International Nuclear Information System (INIS)

Osterbrock, D.E.

1987-01-01

This chapter is devoted to the spectroscopic methods for analyzing the observed plasma in the nuclei of quasars, Seyfert galazies, and active galactic nuclei. Both the narrow-line region and the broad-line region are discussed. Physical models are presented

MULTI-WAVELENGTH PROBES OF OBSCURATION TOWARD THE NARROW-LINE REGION IN SEYFERT GALAXIES

International Nuclear Information System (INIS)

Kraemer, S. B.; Schmitt, H.R.; Crenshaw, D. M.; Melendez, M.; Turner, T.J.; Guainazzi, M.; Mushotzky, R.F.

2011-01-01

We present a study of reddening and absorption toward the narrow line regions (NLRs) in active galactic nuclei (AGNs) selected from the Revised Shapley-Ames, 12 μm, and Swift/Burst Alert Telescope samples. For the sources in host galaxies with inclinations of b/a > 0.5, we find that the mean ratio of [O III] λ5007, from ground-based observations, and [O IV] 28.59 μm, from Spitzer/Infrared Spectrograph observations, is a factor of two lower in Seyfert 2s than Seyfert 1s. The combination of low [O III]/[O IV] and [O III] λ4363/λ5007 ratios in Seyfert 2s suggests more extinction of emission from the NLR than in Seyfert 1s. Similar column densities of dusty gas, N H ∼ several x 10 21 cm -2 , can account for the suppression of both [O III] λ5007 and [O III] λ4363, as compared to those observed in Seyfert 1s. Also, we find that the X-ray line O VII λ22.1 A is weaker in Seyfert 2s, consistent with absorption by the same gas that reddens the optical emission. Using a Hubble Space Telescope/Space Telescope Imaging Spectrograph slitless spectrum of the Seyfert 1 galaxy NGC 4151, we estimate that only ∼30% of the [O III] λ5007 comes from within 30 pc of the central source, which is insufficient to account for the low [O III]/[O IV] ratios in Seyfert 2s. If Seyfert 2 galaxies have similar intrinsic [O III] spatial profiles, the external dusty gas must extend further out along the NLR, perhaps in the form of nuclear dust spirals that have been associated with fueling flows toward the AGN.

X-ray spectral line coincidences between fluorine VIII (and IX) and transition metal lines

International Nuclear Information System (INIS)

Charatis, G.; Rockett, P.D.; Burkhalter, P.G.

1983-01-01

X-ray spectroscopy was performed in the 12 to 15 A region, recording L-shell lines from selected laser-irradiated transition metals. Line coincidences and near coincidences were identified between Fe, Cr, Mn, and Ni L-spectra, and F VIII and F IX K-shell lines. Wavelengths were determined to accuracies of 1 to 3 mA and will be utilized in selecting potential pumping candidates in future x-ray lasing schemes. High-resolution x-ray spectra were collected under controlled illumination and target conditions using 1.05 μm and 0.527 μm laser excitation with the KMS CHROMA laser

Hamiltonian theory of vacuum helical torus lines of magnetic force

International Nuclear Information System (INIS)

Gnudi, Giovanni; Hatori, Tadatsugu

1994-01-01

For making plasma into equilibrium state, the lines of magnetic force must have magnetic surfaces. However in a helical system, space is divided into the region having magnetic surface structure and the region that does not have it. Accordingly, it is an important basic research for the plasma confinement in a helical system to examine where is the boundary of both regions and how is the large area structure of the lines of magnetic force in the boundary region. The lines of magnetic force can be treated as a Hamilton mechanics system, and it has been proved that the Hamiltonian for the lines of magnetic force can be expressed by a set of canonical variables and the function of time. In this research, the Hamiltonian that describes the lines of magnetic force of helical system torus coordination in vacuum was successfully determined concretely. Next, the development of new linear symplectic integration method was carried out. The important supports for the theory of determining Hamiltonian are Lie transformation and paraxial expansion. The procedure is explained. In Appendix, Lie transformation, Hamiltonian for the lines of magnetic force, magnetic potential, Taylor expansion of the potential, cylindrical limit approximation, helical toroidal potential and integrable model are described. (K.I.)

Constancy of spectral-line bisectors

International Nuclear Information System (INIS)

Gray, D.F.

1983-01-01

Bisectors of spectral line profiles in cool stars indicate the strength of convection in the photospheres of these objects. The present investigation is concerned with the feasibility of studying time variations in line bisectors, the reality of apparent line-to-line differences within the same stellar spectrum, and bisector differences between stars of identical spectral types. The differences considered pertain to the shape of the bisector. The material used in the investigation was acquired at the McDonald Observatory using a 1728 diode Reticon array at the coudefocus of the 2.1-m telescope. Observed bisector errors are discussed. It is established that different lines in the same star show significantly different bisectors. The observed error bands are shown by the shaded regions. The slope and curvature are unique for each case

An analysis of representative heating load lines for residential HSPF ratings

Energy Technology Data Exchange (ETDEWEB)

Rice, C. Keith [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shen, Bo [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shrestha, Som S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-07-01

This report describes an analysis to investigate representative heating loads for single-family detached homes using current EnergyPlus simulations (DOE 2014a). Hourly delivered load results are used to determine binned load lines using US Department of Energy (DOE) residential prototype building models (DOE 2014b) developed by Pacific Northwest National Laboratory (PNNL). The selected residential single-family prototype buildings are based on the 2006 International Energy Conservation Code (IECC 2006) in the DOE climate regions. The resulting load lines are compared with the American National Standards Institute (ANSI)/Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Standard 210/240 (AHRI 2008) minimum and maximum design heating requirement (DHR) load lines of the heating seasonal performance factor (HSPF) ratings procedure for each region. The results indicate that a heating load line closer to the maximum DHR load line, and with a lower zero load ambient temperature, is more representative of heating loads predicted for EnergyPlus prototype residential buildings than the minimum DHR load line presently used to determine HSPF ratings. An alternative heating load line equation was developed and compared to binned load lines obtained from the EnergyPlus simulation results. The effect on HSPF of the alternative heating load line was evaluated for single-speed and two-capacity heat pumps, and an average HSPF reduction of 16% was found. The alternative heating load line relationship is tied to the rated cooling capacity of the heat pump based on EnergyPlus autosizing, which is more representative of the house load characteristics than the rated heating capacity. The alternative heating load line equation was found to be independent of climate for the six DOE climate regions investigated, provided an adjustable zero load ambient temperature is used. For Region IV, the default DOE climate region used for HSPF ratings, the higher load line results in an ~28

Dynamics of contact line depinning during droplet evaporation based on thermodynamics.

Science.gov (United States)

Yu, Dong In; Kwak, Ho Jae; Doh, Seung Woo; Ahn, Ho Seon; Park, Hyun Sun; Kiyofumi, Moriyama; Kim, Moo Hwan

2015-02-17

For several decades, evaporation phenomena have been intensively investigated for a broad range of applications. However, the dynamics of contact line depinning during droplet evaporation has only been inductively inferred on the basis of experimental data and remains unclear. This study focuses on the dynamics of contact line depinning during droplet evaporation based on thermodynamics. Considering the decrease in the Gibbs free energy of a system with different evaporation modes, a theoretical model was developed to estimate the receding contact angle during contact line depinning as a function of surface conditions. Comparison of experimentally measured and theoretically modeled receding contact angles indicated that the dynamics of contact line depinning during droplet evaporation was caused by the most favorable thermodynamic process encountered during constant contact radius (CCR mode) and constant contact angle (CCA mode) evaporation to rapidly reach an equilibrium state during droplet evaporation.

A Methodology for Long-Term Analysis of Innovative Signalling Systems on Regional Rail Lines

Directory of Open Access Journals (Sweden)

Luca D'Acierno

2016-10-01

Full Text Available A rail system may be considered a useful tool for reducing vehicular flows on a road system (i.e. cars and trucks, especially in high-density contexts such as urban and metropolitan areas where greenhouse gas emissions need to be abated. In particular, since travellers maximise their own utility, variations in mobility choices can be induced only by significantly improving the level-of-service of public transport. Our specific proposal is to identify the economic and environmental effects of implementing an innovative signalling system (which would reduce passenger waiting times by performing a cost-benefit analysis based on a feasibility threshold approach. Hence, it is necessary to calculate long-term benefits and compare them with intervention costs. In this context, a key factor to be considered is travel demand estimation in current and future conditions. This approach was tested on a regional rail line in southern Italy to show the feasibility and utility of the proposed methodology.

FIRST DETECTION OF NEAR-INFRARED LINE EMISSION FROM ORGANICS IN YOUNG CIRCUMSTELLAR DISKS

Energy Technology Data Exchange (ETDEWEB)

Mandell, Avi M.; Mumma, Michael J.; Villanueva, Geronimo [Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Bast, Jeanette; Van Dishoeck, Ewine F. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Blake, Geoffrey A. [California Institute of Technology, Division of Geological and Planetary Sciences, MS 150-21, Pasadena, CA 91125 (United States); Salyk, Colette, E-mail: Avi.Mandell@nasa.gov [Department of Astronomy, University of Texas, Austin, TX 78712 (United States)

2012-03-10

We present an analysis of high-resolution spectroscopy of several bright T Tauri stars using the CRIRES spectrograph on the Very Large Telescope and NIRSPEC spectrograph on the Keck Telescope, revealing the first detections of emission from HCN and C{sub 2}H{sub 2} in circumstellar disks at near-infrared wavelengths. Using advanced data reduction techniques, we achieve a dynamic range with respect to the disk continuum of {approx}500 at 3 {mu}m, revealing multiple emission features of H{sub 2}O, OH, HCN, and C{sub 2}H{sub 2}. We also present stringent upper limits for two other molecules thought to be abundant in the inner disk, CH{sub 4} and NH{sub 3}. Line profiles for the different detected molecules are broad but centrally peaked in most cases, even for disks with previously determined inclinations of greater than 20 Degree-Sign , suggesting that the emission has both a Keplerian and non-Keplerian component as observed previously for CO emission. We apply two different modeling strategies to constrain the molecular abundances and temperatures: we use a simplified single-temperature local thermal equilibrium (LTE) slab model with a Gaussian line profile to make line identifications and determine a best-fit temperature and initial abundance ratios, and we compare these values with constraints derived from a detailed disk radiative transfer model assuming LTE excitation but utilizing a realistic temperature and density structure. Abundance ratios from both sets of models are consistent with each other and consistent with expected values from theoretical chemical models, and analysis of the line shapes suggests that the molecular emission originates from within a narrow region in the inner disk (R < 1 AU).

Crossing the LINE toward genomic instability: LINE-1 retrotransposition in cancer

Science.gov (United States)

Kemp, Jacqueline; Longworth, Michelle

2015-12-01

Retrotransposons are repetitive DNA sequences that are positioned throughout the human genome. Retrotransposons are capable of copying themselves and mobilizing new copies to novel genomic locations in a process called retrotransposition. While most retrotransposon sequences in the human genome are incomplete and incapable of mobilization, the LINE-1 retrotransposon, which comprises approximately 17% of the human genome, remains active. The disruption of cellular mechanisms that suppress retrotransposon activity is linked to the generation of aneuploidy, a potential driver of tumor development. When retrotransposons insert into a novel genomic region, they have the potential to disrupt the coding sequence of endogenous genes and alter gene expression, which can lead to deleterious consequences for the organism. Additionally, increased LINE-1 copy numbers provide more chances for recombination events to occur between retrotransposons, which can lead to chromosomal breaks and rearrangements. LINE-1 activity is increased in various cancer cell lines and in patient tissues resected from primary tumors. LINE-1 activity also correlates with increased cancer metastasis. This review aims to give a brief overview of the connections between LINE-1 retrotransposition and the loss of genome stability. We will also discuss the mechanisms that repress retrotransposition in human cells and their links to cancer.

Neural correlates of four broad temperament dimensions: testing predictions for a novel construct of personality.

Directory of Open Access Journals (Sweden)

Lucy L Brown

Full Text Available Four suites of behavioral traits have been associated with four broad neural systems: the 1 dopamine and related norepinephrine system; 2 serotonin; 3 testosterone; 4 and estrogen and oxytocin system. A 56-item questionnaire, the Fisher Temperament Inventory (FTI, was developed to define four temperament dimensions associated with these behavioral traits and neural systems. The questionnaire has been used to suggest romantic partner compatibility. The dimensions were named: Curious/Energetic; Cautious/Social Norm Compliant; Analytical/Tough-minded; and Prosocial/Empathetic. For the present study, the FTI was administered to participants in two functional magnetic resonance imaging studies that elicited feelings of love and attachment, near-universal human experiences. Scores for the Curious/Energetic dimension co-varied with activation in a region of the substantia nigra, consistent with the prediction that this dimension reflects activity in the dopamine system. Scores for the Cautious/Social Norm Compliant dimension correlated with activation in the ventrolateral prefrontal cortex in regions associated with social norm compliance, a trait linked with the serotonin system. Scores on the Analytical/Tough-minded scale co-varied with activity in regions of the occipital and parietal cortices associated with visual acuity and mathematical thinking, traits linked with testosterone. Also, testosterone contributes to brain architecture in these areas. Scores on the Prosocial/Empathetic scale correlated with activity in regions of the inferior frontal gyrus, anterior insula and fusiform gyrus. These are regions associated with mirror neurons or empathy, a trait linked with the estrogen/oxytocin system, and where estrogen contributes to brain architecture. These findings, replicated across two studies, suggest that the FTI measures influences of four broad neural systems, and that these temperament dimensions and neural systems could constitute

Neural correlates of four broad temperament dimensions: testing predictions for a novel construct of personality.

Science.gov (United States)

Brown, Lucy L; Acevedo, Bianca; Fisher, Helen E

2013-01-01

Four suites of behavioral traits have been associated with four broad neural systems: the 1) dopamine and related norepinephrine system; 2) serotonin; 3) testosterone; 4) and estrogen and oxytocin system. A 56-item questionnaire, the Fisher Temperament Inventory (FTI), was developed to define four temperament dimensions associated with these behavioral traits and neural systems. The questionnaire has been used to suggest romantic partner compatibility. The dimensions were named: Curious/Energetic; Cautious/Social Norm Compliant; Analytical/Tough-minded; and Prosocial/Empathetic. For the present study, the FTI was administered to participants in two functional magnetic resonance imaging studies that elicited feelings of love and attachment, near-universal human experiences. Scores for the Curious/Energetic dimension co-varied with activation in a region of the substantia nigra, consistent with the prediction that this dimension reflects activity in the dopamine system. Scores for the Cautious/Social Norm Compliant dimension correlated with activation in the ventrolateral prefrontal cortex in regions associated with social norm compliance, a trait linked with the serotonin system. Scores on the Analytical/Tough-minded scale co-varied with activity in regions of the occipital and parietal cortices associated with visual acuity and mathematical thinking, traits linked with testosterone. Also, testosterone contributes to brain architecture in these areas. Scores on the Prosocial/Empathetic scale correlated with activity in regions of the inferior frontal gyrus, anterior insula and fusiform gyrus. These are regions associated with mirror neurons or empathy, a trait linked with the estrogen/oxytocin system, and where estrogen contributes to brain architecture. These findings, replicated across two studies, suggest that the FTI measures influences of four broad neural systems, and that these temperament dimensions and neural systems could constitute foundational mechanisms

[Chromosomal variation in Chironomus plumosus L. (Diptera, Chironomidae) from populations of Bryansk region, Saratov region (Russia), and Gomel region (Belarus)].

Science.gov (United States)

Belyanina, S I

2015-02-01

Cytogenetic analysis was performed on samples of Chironomus plumosus L. (Diptera, Chironomidae) taken from waterbodies of various types in Bryansk region (Russia) and Gomel region (Belarus). Karyotypes of specimens taken from stream pools of the Volga were used as reference samples. The populations of Bryansk and Gomel regions (except for a population of Lake Strativa in Starodubskii district, Bryansk region) exhibit broad structural variation, including somatic mosaicism for morphotypes of the salivary gland chromosome set, decondensation of telomeric sites, and the presence of small structural changes, as opposed to populations of Saratov region. As compared with Saratov and Bryansk regions, the Balbiani ring in the B-arm of chromosome I is repressed in populations of Gomel region. It is concluded that the chromosome set of Ch. plumosus in a range of waterbodies of Bryansk and Gomel regions is unstable.

Moving contact lines on vibrating surfaces

Science.gov (United States)

Solomenko, Zlatko; Spelt, Peter; Scott, Julian

2017-11-01

Large-scale simulations of flows with moving contact lines for realistic conditions generally requires a subgrid scale model (analyses based on matched asymptotics) to account for the unresolved part of the flow, given the large range of length scales involved near contact lines. Existing models for the interface shape in the contact-line region are primarily for steady flows on homogeneous substrates, with encouraging results in 3D simulations. Introduction of complexities would require further investigation of the contact-line region, however. Here we study flows with moving contact lines on planar substrates subject to vibrations, with applications in controlling wetting/dewetting. The challenge here is to determine the change in interface shape near contact lines due to vibrations. To develop further insight, 2D direct numerical simulations (wherein the flow is resolved down to an imposed slip length) have been performed to enable comparison with asymptotic theory, which is also developed further. Perspectives will also be presented on the final objective of the work, which is to develop a subgrid scale model that can be utilized in large-scale simulations. The authors gratefully acknowledge the ANR for financial support (ANR-15-CE08-0031) and the meso-centre FLMSN for use of computational resources. This work was Granted access to the HPC resources of CINES under the allocation A0012B06893 made by GENCI.

Differential regional gray matter volumes in patients with on-line game addiction and professional gamers

Science.gov (United States)

Han, Doug Hyun; Lyoo, In Kyoon; Renshaw, Perry F.

2015-01-01

Patients with on-line game addiction (POGA) and professional video game players play video games for extended periods of time, but experience very different consequences for their on-line game play. Brain regions consisting of anterior cingulate, thalamus and occpito-temporal areas may increase the likelihood of becoming a pro-gamer or POGA. Twenty POGA, seventeen pro-gamers, and eighteen healthy comparison subjects (HC) were recruited. All magnetic resonance imaging (MRI) was performed on a 1.5 Tesla Espree MRI scanner (SIEMENS, Erlangen, Germany). Voxel-wise comparisons of gray matter volume were performed between the groups using the two-sample t-test with statistical parametric mapping (SPM5). Compared to HC, the POGA group showed increased impulsiveness and perseverative errors, and volume in left thalamus gray matter, but decreased gray matter volume in both inferior temporal gyri, right middle occipital gyrus, and left inferior occipital gyrus, compared with HC. Pro-gamers showed increased gray matter volume in left cingulate gyrus, but decreased gray matter volume in left middle occipital gyrus and right inferior temporal gyrus compared with HC. Additionally, the pro-gamer group showed increased gray matter volume in left cingulate gyrus and decreased left thalamus gray matter volume compared with the POGA group. The current study suggests that increased gray matter volumes of the left cingulate gyrus in pro-gamers and of the left thalamus in POGA may contribute to the different clinical characteristics of pro-gamers and POGA. PMID:22277302

SU-F-BRD-15: Quality Correction Factors in Scanned Or Broad Proton Therapy Beams Are Indistinguishable

International Nuclear Information System (INIS)

Sorriaux, J; Lee, J; Testa, M; Paganetti, H; Bertrand, D; Orban de Xivry, J; Palmans, H; Vynckier, S; Sterpin, E

2015-01-01

Purpose: The IAEA TRS-398 code of practice details the reference conditions for reference dosimetry of proton beams using ionization chambers and the required beam quality correction factors (kQ). Pencil beam scanning (PBS) requires multiple spots to reproduce the reference conditions. The objective is to demonstrate, using Monte Carlo (MC) calculations, that kQ factors for broad beams can be used for scanned beams under the same reference conditions with no significant additional uncertainty. We consider hereafter the general Alfonso formalism (Alfonso et al, 2008) for non-standard beam. Methods: To approach the reference conditions and the associated dose distributions, PBS must combine many pencil beams with range modulation and shaping techniques different than those used in passive systems (broad beams). This might lead to a different energy spectrum at the measurement point. In order to evaluate the impact of these differences on kQ factors, ion chamber responses are computed with MC (Geant4 9.6) in a dedicated scanned pencil beam (Q-pcsr) producing a 10×10cm2 composite field with a flat dose distribution from 10 to 16 cm depth. Ion chamber responses are also computed by MC in a broad beam with quality Q-ds (double scattering). The dose distribution of Q -pcsr matches the dose distribution of Q-ds. k-(Q-pcsr,Q-ds) is computed for a 2×2×0.2cm 3 idealized air cavity and a realistic plane-parallel ion chamber (IC). Results: Under reference conditions, quality correction factors for a scanned composite field versus a broad beam are the same for air cavity dose response, k-(Q-pcsr,Q-ds) =1.001±0.001 and for a Roos IC, k-(Q-pcsr,Q-ds) =0.999±0.005. Conclusion: Quality correction factors for ion chamber response in scanned and broad proton therapy beams are identical under reference conditions within the calculation uncertainties. The results indicate that quality correction factors published in IAEA TRS-398 can be used for scanned beams in the SOBP of a high

SU-F-BRD-15: Quality Correction Factors in Scanned Or Broad Proton Therapy Beams Are Indistinguishable

Energy Technology Data Exchange (ETDEWEB)

Sorriaux, J; Lee, J [Molecular Imaging Radiotherapy & Oncology, Universite Catholique de Louvain, Brussels (Belgium); ICTEAM Institute, Universite catholique de Louvain, Louvain-la-Neuve (Belgium); Testa, M; Paganetti, H [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, Massachusetts (United States); Bertrand, D; Orban de Xivry, J [Ion Beam Applications, Louvain-la-neuve, Brabant Wallon (Belgium); Palmans, H [EBG MedAustron GmbH, Wiener Neustadt (Austria); National Physical Laboratory, Teddington (United Kingdom); Vynckier, S [Cliniques Universitaires Saint-Luc, Brussels (Belgium); Sterpin, E [Molecular Imaging Radiotherapy & Oncology, Universite Catholique de Louvain, Brussels (Belgium)

2015-06-15

Purpose: The IAEA TRS-398 code of practice details the reference conditions for reference dosimetry of proton beams using ionization chambers and the required beam quality correction factors (kQ). Pencil beam scanning (PBS) requires multiple spots to reproduce the reference conditions. The objective is to demonstrate, using Monte Carlo (MC) calculations, that kQ factors for broad beams can be used for scanned beams under the same reference conditions with no significant additional uncertainty. We consider hereafter the general Alfonso formalism (Alfonso et al, 2008) for non-standard beam. Methods: To approach the reference conditions and the associated dose distributions, PBS must combine many pencil beams with range modulation and shaping techniques different than those used in passive systems (broad beams). This might lead to a different energy spectrum at the measurement point. In order to evaluate the impact of these differences on kQ factors, ion chamber responses are computed with MC (Geant4 9.6) in a dedicated scanned pencil beam (Q-pcsr) producing a 10×10cm2 composite field with a flat dose distribution from 10 to 16 cm depth. Ion chamber responses are also computed by MC in a broad beam with quality Q-ds (double scattering). The dose distribution of Q -pcsr matches the dose distribution of Q-ds. k-(Q-pcsr,Q-ds) is computed for a 2×2×0.2cm{sup 3} idealized air cavity and a realistic plane-parallel ion chamber (IC). Results: Under reference conditions, quality correction factors for a scanned composite field versus a broad beam are the same for air cavity dose response, k-(Q-pcsr,Q-ds) =1.001±0.001 and for a Roos IC, k-(Q-pcsr,Q-ds) =0.999±0.005. Conclusion: Quality correction factors for ion chamber response in scanned and broad proton therapy beams are identical under reference conditions within the calculation uncertainties. The results indicate that quality correction factors published in IAEA TRS-398 can be used for scanned beams in the SOBP of a

Cell line name recognition in support of the identification of synthetic lethality in cancer from text

Science.gov (United States)

Kaewphan, Suwisa; Van Landeghem, Sofie; Ohta, Tomoko; Van de Peer, Yves; Ginter, Filip; Pyysalo, Sampo

2016-01-01

Motivation: The recognition and normalization of cell line names in text is an important task in biomedical text mining research, facilitating for instance the identification of synthetically lethal genes from the literature. While several tools have previously been developed to address cell line recognition, it is unclear whether available systems can perform sufficiently well in realistic and broad-coverage applications such as extracting synthetically lethal genes from the cancer literature. In this study, we revisit the cell line name recognition task, evaluating both available systems and newly introduced methods on various resources to obtain a reliable tagger not tied to any specific subdomain. In support of this task, we introduce two text collections manually annotated for cell line names: the broad-coverage corpus Gellus and CLL, a focused target domain corpus. Results: We find that the best performance is achieved using NERsuite, a machine learning system based on Conditional Random Fields, trained on the Gellus corpus and supported with a dictionary of cell line names. The system achieves an F-score of 88.46% on the test set of Gellus and 85.98% on the independently annotated CLL corpus. It was further applied at large scale to 24 302 102 unannotated articles, resulting in the identification of 5 181 342 cell line mentions, normalized to 11 755 unique cell line database identifiers. Availability and implementation: The manually annotated datasets, the cell line dictionary, derived corpora, NERsuite models and the results of the large-scale run on unannotated texts are available under open licenses at http://turkunlp.github.io/Cell-line-recognition/. Contact: sukaew@utu.fi PMID:26428294

Variations of the Hβ-emission line during a large flare on UV Ceti

International Nuclear Information System (INIS)

Moffett, T.J.; Evans, D.S.; Ferland, G.

1977-01-01

Simultaneous high-speed photometry and photoelectric scanner observations of the Hβ-line were obtained for five flare events, one a major flare, on UV Ceti on 1975 January 6. The relative increase in the intensity of the Hβ-line during the large flare was much greater than the relative continuum rise as measured both by the scanner and by broad-band photometric observations. In Hβ the flare lasted nearly 30 times as long as in the continuum. Peak intensity in the Hβ-line occurred later than the continuum maximum. The possibility of using emission line observations to detect flare activity on early spectral-type stars (dK - dG) is discussed. Some speculations on the mechanism of flare production are indulged. (author)

The broad-band overlap problem in atmospheric trace gases

International Nuclear Information System (INIS)

Subasilar, B.

1991-01-01

In relation to a better understanding of climate change and the related greenhouse problem, one way of projecting for the next decades is through general circulation models (GCMs). The only input as a driving force in the changing atmospheric and oceanic circulation patterns is the amount of heat perturbation either due to natural or man-caused activities. Among these, CO 2 concentrations resulting from the latter has been observed to be accelerating at alarmingly high rates especially after the advent of the industrialization which just began in the last century. In addition to that, collective effects of other greenhouse gases (freons, SO 2 , H 2 O, CH 4 , etc.) are as important as CO 2 . Hence, it is evident from the above considerations that, in the predictions of climate models, the heat input which triggers changes in the atmospheric patterns, should be formulated accurately. In order to realize this objective, in this research, beginning with the available line parameter data, the problems of absorption have been investigated and attacked in the frame known as the broad band modeling since that is the only best and fastest manageable representation for GCMs. The first step was the construction of a full broad band (intra band overlap) model that was also flexible enough to accommodate the individual peculiarities of the bands. Before, the well known and very useful Ramanathan model had a limited applicability in the concentration scale, and it was also not systematically or successfully incorporated into an inter band overlap picture. Then, the established ideas that served as bases up to present, have been employed but found to have a limited practical applicability when it came to predict the inter band overlaps

Synthetic RNAs Mimicking Structural Domains in the Foot-and-Mouth Disease Virus Genome Elicit a Broad Innate Immune Response in Porcine Cells Triggered by RIG-I and TLR Activation.

Science.gov (United States)

Borrego, Belén; Rodríguez-Pulido, Miguel; Revilla, Concepción; Álvarez, Belén; Sobrino, Francisco; Domínguez, Javier; Sáiz, Margarita

2015-07-17

The innate immune system is the first line of defense against viral infections. Exploiting innate responses for antiviral, therapeutic and vaccine adjuvation strategies is being extensively explored. We have previously described, the ability of small in vitro RNA transcripts, mimicking the sequence and structure of different domains in the non-coding regions of the foot-and-mouth disease virus (FMDV) genome (ncRNAs), to trigger a potent and rapid innate immune response. These synthetic non-infectious molecules have proved to have a broad-range antiviral activity and to enhance the immunogenicity of an FMD inactivated vaccine in mice. Here, we have studied the involvement of pattern-recognition receptors (PRRs) in the ncRNA-induced innate response and analyzed the antiviral and cytokine profiles elicited in swine cultured cells, as well as peripheral blood mononuclear cells (PBMCs).

Field-Lines-Threaded Model for: (1) the Low Solar Corona; (2) Electrons in the Transition Region; and (3) Solar Energetic Particle Acceleration and Transport

Science.gov (United States)

Sokolov, I.; van der Holst, B.; Jin, M.; Gombosi, T. I.; Taktakishvili, A.; Khazanov, G. V.

2013-12-01

In numerical simulations of the solar corona, both for the ambient state and especially for dynamical processes the most computational resources are spent for maintaining the numerical solution in the Low Solar Corona and in the transition region, where the temperature gradients are very sharp and the magnetic field has a complicated topology. The degraded computational efficiency is caused by the need in a highest resolution as well as the use of the fully three-dimensional implicit solver for electron heat conduction. On the other hand, the physical nature of the processes involved is rather simple (which still does not facilitate the numerical methods) as long as the heat fluxes as well as slow plasma motional velocities are aligned with the magnetic field. The Alfven wave turbulence, which is often believed to be the main driver of the solar wind and the main source of the coronal heating, is characterized by the Poynting flux of the waves, which is also aligned with the magnetic field. Therefore, the plasma state in any point of the three-dimensional grid in the Low Solar Corona can be found by solving a set of one-dimensional equations for the magnetic field line ('thread'), which passes through this point and connects it to the chromosphere and to the global Solar Corona. In the present paper we describe an innovative computational technology based upon the use of the magnetic-field-line-threads to find the local solution. We present the development of the AWSoM code of the University of Michigan with the field-lines-threaded Low Solar Corona. In the transition region, where the essentially kinetic description of the electron energy fluxes is required, we solve the Fokker-Plank equation on the system of threads, to achieve the physically consistent description of chromosphere evaporation. The third application for the field-lines-treaded model is the Solar Energetic Particle (SEP) acceleration and transport. Being the natural extension of the Field-Line

Active power line conditioners design, simulation and implementation for improving power quality

CERN Document Server

Revuelta, Patricio Salmeron; Litrán, Salvador Pérez

2015-01-01

Active Power Line Conditioners: Design, Simulation and Implementation for Improving Power Quality presents a rigorous theoretical and practical approach to active power line conditioners, one of the subjects of most interest in the field of power quality. Its broad approach offers a journey that will allow power engineering professionals, researchers, and graduate students to learn more about the latest landmarks on the different APLC configurations for load active compensation. By introducing the issues and equipment needs that arise when correcting the lack of power quality in power grids

Power scaling and experimentally fitted model for broad area quantum cascade lasers in continuous wave operation

Science.gov (United States)

Suttinger, Matthew; Go, Rowel; Figueiredo, Pedro; Todi, Ankesh; Shu, Hong; Leshin, Jason; Lyakh, Arkadiy

2018-01-01

Experimental and model results for 15-stage broad area quantum cascade lasers (QCLs) are presented. Continuous wave (CW) power scaling from 1.62 to 2.34 W has been experimentally demonstrated for 3.15-mm long, high reflection-coated QCLs for an active region width increased from 10 to 20 μm. A semiempirical model for broad area devices operating in CW mode is presented. The model uses measured pulsed transparency current, injection efficiency, waveguide losses, and differential gain as input parameters. It also takes into account active region self-heating and sublinearity of pulsed power versus current laser characteristic. The model predicts that an 11% improvement in maximum CW power and increased wall-plug efficiency can be achieved from 3.15 mm×25 μm devices with 21 stages of the same design, but half doping in the active region. For a 16-stage design with a reduced stage thickness of 300 Å, pulsed rollover current density of 6 kA/cm2, and InGaAs waveguide layers, an optical power increase of 41% is projected. Finally, the model projects that power level can be increased to ˜4.5 W from 3.15 mm×31 μm devices with the baseline configuration with T0 increased from 140 K for the present design to 250 K.

Linewidth statistics of single InGaAs quantum dot photolumincescence lines

DEFF Research Database (Denmark)

Leosson, Kristjan; Jensen, Jacob Riis; Hvam, Jørn Märcher

2000-01-01

We have used photoluminescence spectroscopy with high spatial and spectral resolution to measure the linewidths of single emission lines from In0.5Ga0.5As/GaAs self-assembled quantum dots. At 10 K, we find a broad, asymmetric distribution of linewidths with a maximum at 50 mu eV. The distribution......-dot luminescence lines depends only weakly on temperature up to 50 K, showing a broadening of 0.4 mu eV/K. Above 50 K, a thermally activated behavior of the linewidth is observed. This temperature dependence is consistent with the discrete energy level structure of the dots....

Hyperfine structure investigations of Pr-I lines in the region 4200-4450 A

Energy Technology Data Exchange (ETDEWEB)

Siddiqui, Imran; Khan, Shamim; Tanweer Iqbal, Syed; Windholz, Laurentius [Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A 8010 Graz (Austria)

2012-07-01

Praseodymium I spectral lines were investigated using laser induced fluorescence spectroscopy in a hollow cathode discharge lamp. The investigations led to the discovery of new Pr I energy levels of even and odd parity. A high resolution Fourier transform (FT) spectrum was used to extract promising excitation wavelengths. In the FT spectrum the investigated line 4375.53 A shows up as a narrow peak hfs with a weak SNR. Nevertheless, the line was excited and fluorescence signals were observed on 6 lines (4163 A, 4816 A, 5091 A, 5164 A, 5209 A, 5233 A). The hfs of the line was recorded by scanning the laser frequency and was fitted to obtain angular momentum J and hf constant A of the combining levels. We got J{sub up}=5/2, A{sub up}=1028.30 MHz, J{sub lo}=7/2 and A{sub lo}=861.46 MHz (the subscripts refer to upper and lower level). Assuming an unknown upper level, a known lower level was searched among the known levels having sufficient values of J and A. The level 7617.440 cm{sup -1}, even parity, J{sub lo}=7/2 and A{sub lo}=868 MHz fulfils these requirements. Using the center of gravity wave number of the line 4375.53 A and the energy of the lower level, the unknown upper level was calculated to have 30465.424 cm{sup -1}, odd parity, J{sub up}=5/2 and A{sub up}=1033(6) MHz.

Spectroscopic and polarimetric study of radio-quiet weak emission line quasars