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3141. XQ-100. X-shooter quasar spectra
ID:
ivo://CDS.VizieR/J/MNRAS/462/3285
Title:
XQ-100. X-shooter quasar spectra
Short Name:
J/MNRAS/462/3285
Date:
21 Oct 2021
Publisher:
CDS
Description:
We statistically study the physical properties of a sample of narrow absorption line (NAL) systems looking for empirical evidences to distinguish between intrinsic and intervening NALs without taking into account any a priori definition or velocity cut-off. We analyse the spectra of 100 quasars with 3.5<z_em_<4.5, observed with X-shooter/Very Large Telescope in the context of the XQ-100 Legacy Survey. We detect an ~8{sigma} excess in the CIV number density within 10000km/s of the quasar emission redshift with respect to the random occurrence of NALs. This excess does not show a dependence on the quasar bolometric luminosity and it is not due to the redshift evolution of NALs. It extends far beyond the standard 5000km/s cut-off traditionally defined for associated absorption lines. We propose to modify this definition, extending the threshold to 10000km/s when weak absorbers (equivalent width <0.2{AA}) are also considered. We infer NV is the ion that better traces the effects of the quasar ionization field, offering the best statistical tool to identify intrinsic systems. Following this criterion, we estimate that the fraction of quasars in our sample hosting an intrinsic NAL system is 33 per cent. Lastly, we compare the properties of the material along the quasar line of sight, derived from our sample, with results based on close quasar pairs investigating the transverse direction. We find a deficiency of cool gas (traced by C II) along the line of sight connected to the quasar host galaxy, in contrast with what is observed in the transverse direction.
3142. X-ray AGNs with Subaru/FMOS NIR observations
ID:
ivo://CDS.VizieR/J/ApJ/815/129
Title:
X-ray AGNs with Subaru/FMOS NIR observations
Short Name:
J/ApJ/815/129
Date:
21 Oct 2021
Publisher:
CDS
Description:
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.
3143. X-ray data for 56 protoplanetary disk sources
ID:
ivo://CDS.VizieR/J/A+A/625/A66
Title:
X-ray data for 56 protoplanetary disk sources
Short Name:
J/A+A/625/A66
Date:
21 Oct 2021
Publisher:
CDS
Description:
Consistent modeling of protoplanetary disks requires the simultaneous solution of both continuum and line radiative transfer, heating and cooling balance between dust and gas and, of course, chemistry. Such models depend on panchromatic observations that can provide a complete description of the physical and chemical properties and energy balance of protoplanetary systems. Along these lines we present a homogeneous, panchromatic collection of data on a sample of 85 T Tauri and Herbig Ae objects for which data cover a range from X-rays to centimeter wavelengths. Datasets consist of photometric measurements, spectra, along with results from the data analysis such as line fluxes from atomic and molecular transitions. Additional properties resulting from modeling of the sources such as disc mass and shape parameters, dust size and PAH properties are also provided for completeness. The purpose of this data collection is to provide a solid base that can enable consistent modeling of the properties of protoplan- etary disks. To this end, we performed an unbiased collection of publicly available data that were combined to homogeneous datasets adopting consistent criteria. Targets were selected based on both their properties but also on the availability of data. Data from more than 50 different telescopes and facilities were retrieved and combined in homogeneous datasets directly from public data archives or after being extracted from more than 100 published articles. X-ray data for a subset of 56 sources represent an exception as they were reduced from scratch and are presented here for the first time. Compiled datasets along with a subset of continuum and emission-line models are stored in a dedicated database and distributed through a publicly accessible online system. All datasets contain metadata descriptors that allow to backtrack them to their original resources. The graphical user interface of the online system allows the user to visually inspect individual objects but also compare between datasets and models. It also offers to the user the possibility to download any of the stored data and metadata for further processing.
3144. X-ray & MIR AGNs in Stripe 82 with eBOSS spectra
ID:
ivo://CDS.VizieR/J/ApJ/876/50
Title:
X-ray & MIR AGNs in Stripe 82 with eBOSS spectra
Short Name:
J/ApJ/876/50
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of a Sloan Digital Sky Survey IV eBOSS program to target X-ray sources and mid-infrared-selected Wide-field Infrared Survey Explorer (WISE) active galactic nucleus (AGN) candidates in a 36.8deg^2^ region of Stripe 82. About half this survey (15.6deg^2^) covers the largest contiguous portion of the Stripe 82 X-ray survey. This program represents the largest spectroscopic survey of AGN candidates selected solely by their WISE colors. We combine this sample with X-ray and WISE AGNs in the field identified via other sources of spectroscopy, producing a catalog of 4847 sources that is 82% complete to r~22. Based on X-ray luminosities or WISE colors, 4730 of these sources are AGNs, with a median sample redshift of z~1. About 30% of the AGNs are optically obscured (i.e., lack broad lines in their optical spectra). BPT analysis, however, indicates that 50% of the WISE AGNs at z<0.5 have emission line ratios consistent with star-forming galaxies, so whether they are buried AGNs or star-forming galaxy contaminants is currently unclear. We find that 61% of X-ray AGNs are not selected as mid-infrared AGNs, with 22% of X-ray AGNs undetected by WISE. Most of these latter AGNs have high X-ray luminosities (Lx>10^44^erg/s), indicating that mid-infrared selection misses a sizable fraction of the highest luminosity AGNs, as well as lower luminosity sources where AGN-heated dust is not dominating the mid-infrared emission. Conversely, ~58% of WISE AGNs are undetected by X-rays, though we do not find that they are preferentially redder than the X-ray-detected WISE AGNs.
3145. X-ray selected ROSAT AGN spectra
ID:
ivo://CDS.VizieR/J/A+A/350/805
Title:
X-ray selected ROSAT AGN spectra
Short Name:
J/A+A/350/805
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the emission line properties of a sample of 76 bright soft X-ray selected ROSAT Active Galactic Nuclei. All optical counterparts are Seyfert 1 galaxies with rather narrow permitted lines, strong optical FeII line blends, and weak forbidden lines. By selection, they also have steep soft X-ray spectra when compared with typical Seyfert 1 galaxies. We discuss possible origins of these peculiar trends employing detailed correlation analyses, including a Principal Component Analysis. The optical spectra are presented in the Appendix.
3146. X-ray sources in Galactic Center
ID:
ivo://CDS.VizieR/J/ApJ/613/1179
Title:
X-ray sources in Galactic Center
Short Name:
J/ApJ/613/1179
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine the X-ray spectra and variability of the sample of X-ray sources with L_X_~10^31^-10^33^ergs/s identified within the inner 9' of the Galaxy by Muno et al. Very few of the sources exhibit intraday or intermonth variations.
3147. X-ray spectra in 13^H^ XMM/Chandra deep field
ID:
ivo://CDS.VizieR/J/MNRAS/369/156
Title:
X-ray spectra in 13^H^ XMM/Chandra deep field
Short Name:
J/MNRAS/369/156
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the X-ray spectra of 86 optically identified sources in the 13^H^ XMM-Newton/Chandra deep field which have >70 X-ray counts. The majority of these sources have 2-10keV fluxes between 10-15 and 5x10^-14^erg/cm^2^/s. The sample consists of 50 broad-line active galactic nuclei (BLAGN), 25 narrow emission-line galaxies (NELGs), six absorption-line galaxies and five Galactic stars. The majority (42/50) of the BLAGN have X-ray spectra which are consistent with a power-law shape.
3148. X-ray spectra of 4 cool stars
ID:
ivo://CDS.VizieR/J/A+A/416/281
Title:
X-ray spectra of 4 cool stars
Short Name:
J/A+A/416/281
Date:
21 Oct 2021
Publisher:
CDS
Description:
These tables include the observed fluxes of the lines identified in the X-ray spectra of four cool stars (Procyon, epsilon Eri, lambda And and V851 Cen). The spectra were taken using different configurations (Chandra/LETG, Chandra/HETG and XMM/RGS). The tables list the observed fluxes at Earth, and a comparison with the fluxes predicted for a given thermal coronal structure (the Emission Measure Distribution, EMD), the emissivities provided by the Astrophysical Plasma Emission Model (APED) and column density of absorbing material in the interstellar medium towards the star. A list of the most important (at least a 5% of the flux predicted for the line) blends that have been considered for each line is included.
3149. X-ray spectrum of 1H0419-577
ID:
ivo://CDS.VizieR/J/A+A/556/A94
Title:
X-ray spectrum of 1H0419-577
Short Name:
J/A+A/556/A94
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we analyze the X-ray, UV and optical data of the Seyfert 1.5 galaxy 1H0419-577, with the aim of detecting and studying an ionized-gas outflow. The source was observed simultaneously in the X-rays with XMM-Newton and in the UV with HST-COS. Optical data were also acquired with the XMM-Newton Optical Monitor. We detected a thin, lowly ionized warm absorber (logxi~0.03, logNH~19.9cm^-2^) in the X-ray spectrum, consistent to be produced by the same outflow already detected in the UV. Provided the gas density estimated in the UV, the outflow is consistent to be located in the host galaxy, at ~kpc scale. Narrow emission lines were detected in the X-rays, in the UV and also in the optical spectrum. A single photoionized-gas model cannot account for all the narrow lines emission, indicating that the narrow line region is probably a stratified environment, differing in density and ionization. X-ray lines are unambiguously produced in a more highly ionized gas phase than the one emitting the UV lines. The analysis suggests also that the X-ray emitter may be just a deeper portion of the same gas layer producing the UV lines. Optical lines are probably produced in another, disconnected gas system. The different ionization condition, and the ~pc scale location suggested by the line width for the narrow lines emitters, argue against a connection between the warm absorber and the narrow line region in this source.
3150. X-ray spectrum of SV Cam
ID:
ivo://CDS.VizieR/J/A+A/445/673
Title:
X-ray spectrum of SV Cam
Short Name:
J/A+A/445/673
Date:
21 Oct 2021
Publisher:
CDS
Description:
The eclipsing active binary SV Cam (G0V/K6V, P_orb_=0.593071d) was observed with XMM-Newton during two campaigns in 2001 and 2003.

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