- ID:
- ivo://CDS.VizieR/J/ApJ/890/71
- Title:
- 5100{AA} continuum & emission lines LCs of PG2130+099
- Short Name:
- J/ApJ/890/71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As one of the most interesting Seyfert 1 galaxies, PG 2130+099 has been the target of several reverberation mapping (RM) campaigns over the years. However, its measured broad H{beta} line responses have been inconsistent, with time lags of ~200days, ~25days, and ~10days being reported for different epochs while its optical luminosity changed no more than 40%. To investigate this issue, we conducted a new RM-campaign with homogenous and high cadence (about ~3days) for two years during 2017-2019 to measure the kinematics and structure of the ionized gas. We successfully detected time lags of broad H{beta}, HeII, HeI, and FeII lines with respect to the varying 5100{AA} continuum, revealing a stratified structure that is likely virialized with Keplerian kinematics in the first year of observations, but an inflow kinematics of the broad-line region from the second year. With a central black hole mass of 0.97_-0.18_^+0.15^x10^7^M_{sun}_, PG2130+099 has an accretion rate of 10^2.1+/-0.5^L_Edd_c^-2^, where L_Edd_ is the Eddington luminosity and c is speed of light, implying that it is a super-Eddington accretor and likely possesses a slim, rather than thin, accretion disk. The fast changes of the ionization structures of the three broad lines remain puzzling.
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- ID:
- ivo://CDS.VizieR/J/ApJS/235/11
- Title:
- Absorption features in SDSS. I. MgII abs. doublets
- Short Name:
- J/ApJS/235/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the SDSS spectra of quasars included in the DR7Q or DR12Q catalogs, we search for MgII{lambda}{lambda}2796,2803 narrow absorption doublets in the spectra data around MgII{lambda}2798 emission lines. We obtain 17316 MgII doublets, within the redshift range of 0.3299<=z_abs_<=2.5663. We find that a velocity offset of {upsilon}_r_<6000km/s is a safe boundary to constrain the vast majority of associated Mg ii systems, although we find some doublets at {upsilon}_r_>6000km/s. If associated Mg ii absorbers are defined by {upsilon}_r_<6000km/s, ~33.3% of the absorbers are supposed to be contaminants of intervening systems. Removing the 33.3% contaminants, ~4.5% of the quasars present at least one associated MgII system with W_r_^{lambda}2796^>=0.2{AA}. The fraction of associated MgII systems with high-velocity outflows correlates with the average luminosities of their central quasars, indicating a relationship between outflows and the quasar feedback power. The {upsilon}_r_ distribution of the outflow MgII absorbers is peaked at 1023km/s, which is smaller than the corresponding value of the outflow CIV absorbers. The redshift number density evolution of absorbers (dn/dz) limited by {upsilon}_r_{>}-3000km/s differs from that of absorbers constrained by {upsilon}_r_>2000km/s. Absorbers limited by {upsilon}_r_>2000km/s and higher values exhibit profiles similar to dn/dz. In addition, the dn/dz is smaller when absorbers are constrained with larger {upsilon}_r_. The distributions of equivalent widths, and the ratio of W_r_^{lambda}2796^/W_r_^{lambda}2803^, are the same for associated and intervening systems, and independent of quasar luminosity.
- ID:
- ivo://CDS.VizieR/J/A+A/318/347
- Title:
- Absorption lines in QSO 0000-2619
- Short Name:
- J/A+A/318/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We give the list of absorption lines in the high resolution (FWHM=13 km/s) spectrum of the z=4.12 QSO 0000-2619. The first table contains the lines of the Lyman-alpha forest, while in the second table the lines of the metal systems are listed.
- ID:
- ivo://CDS.VizieR/J/A+A/412/707
- Title:
- Absorption-line systems in QSO spectra - CoALS
- Short Name:
- J/A+A/412/707
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Absorption lines and absorption-line systems (ALSs) observed in the spectra of QSOs contain fundamental information on distribution of matter between the observer and the QSO, and on physical processes in the Universe in different epochs of the cosmological evolution. The presented catalog contains a compilation of basic information on absorption-line systems (ALSs) in QSO spectra. The data are taken from publications available to the authors up to January 2002. The catalog includes, in particular, all the data of the catalogs by Junkkarinen et al. (1991ApJS...77..203J) and York et al. (1991MNRAS.250...24Y ). The catalog consists of table1.dat, table2.txt and the list of references in refs.dat file. The present catalog is also available at the site of the Dept. of Theor. Astrophys. of the Ioffe Physical Technical Institute: <www.ioffe.ru/astro/QC>
- ID:
- ivo://CDS.VizieR/J/A+AS/127/217
- Title:
- Absorption spectrum of the QSO PKS2126-158
- Short Name:
- J/A+AS/127/217
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectra of the z_em_=3.268 quasar PKS 2126-158 have been obtained in the wavelength range 430-662nm with a resolution R=27000 and an average signal to noise ratio s/n=25 per resolution element. 12 metal absorption systems have been identified, two of which were previously unknown. All the lines shortward of the Lyman{alpha} emission not identified as due to metals have been fitted as Lyman{alpha} and Lyman{beta}. We reported statistical analysis of this sample of lines. In particular, the two-point correlation function for metal systems has been computed.
- ID:
- ivo://CDS.VizieR/J/A+A/294/377
- Title:
- Absorption systems of HS 1700+6416
- Short Name:
- J/A+A/294/377
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Ultraviolet observations of the high-redshift quasat HS 1700+6416 were obtained with the Faint Object Spectrograph (FOS) onboard the Hubble Space Telescope (HST) in the range 115-328nm, on 1991-12-13/14 and 1992-02-13/14 at a resolution R=1300. The identification of the numerous absoprtion lines provides evidence for 15 heavy-element absorption systems, among them 7 Lyman Limit systems (LLS).
- ID:
- ivo://CDS.VizieR/J/ApJS/155/351
- Title:
- Absorption toward PG 1116+215
- Short Name:
- J/ApJS/155/351
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Hubble Space Telescope (HST) and Far Ultraviolet Spectroscopic Explorer (FUSE) observations of the intergalactic absorption toward QSO PG 1116+215 in the 900-3000{AA} spectral region.
- ID:
- ivo://CDS.VizieR/J/MNRAS/243/1
- Title:
- A catalogue of faint UV-excess objects
- Short Name:
- J/MNRAS/243/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectra, positions, magnitudes and colours are presented for 1400 faint (B<~21mag) stellar objects identified in a complete, ultraviolet-excess (UVX) survey. The objects were selected from COSMOS machine measurements of UK Schmidt U and J plates and observed with the Fibre Optic Coupled Aperture Plate (FOCAP) system at the Anglo-Australian Telescope (AAT). In total, 420 QSOs were identified, of which nine belong to the broad absorption line (BAL) class of QSOs. A further 57 galaxies with narrow emission lines were found. Halo subdwarfs from the vast majority (~90 per cent) of the 824 galactic stars identified in this survey; the remaining galactic stars are comprised principally of hot white dwarfs (42 objects) and horizontal branch stars (nine objects). Updated versions of the QSO number-magnitude relation and luminosity function derived from this survey are also presented in this paper.
- ID:
- ivo://CDS.VizieR/J/A+A/607/A48
- Title:
- AGN data and absorption-line measurements
- Short Name:
- J/A+A/607/A48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Milky Way is surrounded by large amounts of diffuse gaseous matter that connects the stellar body of our Galaxy with its large-scale Local Group (LG) environment. To characterize the absorption properties of this circumgalactic medium (CGM) and its relation to the LG we present the so-far largest survey of metal absorption in Galactic high-velocity clouds (HVCs) using archival ultraviolet (UV) spectra of extragalactic background sources. The UV data are obtained with the Cosmic Origins Spectrograph (COS) onboard the Hubble Space Telescope (HST) and are supplemented by 21cm radio observations of neutral hydrogen. Along 270 sightlines we measure metal absorption in the lines of SiII, SiIII, CII, and CIV and associated HI 21cm emission in HVCs in the velocity range |v_LSR_|=100-500km/s. With this unprecedented large HVC sample we were able to improve the statistics on HVC covering fractions, ionization conditions, small-scale structure, CGM mass, and inflow rate. For the first time, we determine robustly the angular two point correlation function of the high-velocity absorbers, systematically analyze antipodal sightlines on the celestial sphere, and compare the HVC absorption characteristics with that of Damped Lyman alpha absorbers (DLAs) and constrained cosmological simulations of the LG (CLUES project). The overall sky-covering fraction of high-velocity absorption is 77+/-6 percent for the most sensitive ion in our survey, SiIII, and for column densities log N(SiIII)>12.1. This value is 4-5 times higher than the covering fraction of 21 cm neutral hydrogen emission at log N(HI)>18.7 along the same lines of sight, demonstrating that the Milky Way's CGM is multi-phase and predominantly ionized. The measured equivalent-width ratios of SiII, SiIII, CII, and CIV are inhomogeneously distributed on large and small angular scales, suggesting a complex spatial distribution of multi-phase gas that surrounds the neutral 21cm HVCs. We estimate that the total mass and accretion rate of the neutral and ionized CGM traced by HVCs is M_HVC_>3.0x10^9^M_{sun}_ and dM_HVC_/dt>6.1M_{sun}_/yr, where the Magellanic Stream (MS) contributes with more than 90 percent to this mass/mass-flow. If seen from an external vantage point, the Milky Way disk plus CGM would appear as a DLA that would exhibit for most viewing angles an extraordinary large velocity spread of dv=400-800km/s, a result of the complex kinematics of the Milky Way CGM that is dominated by the presence of the MS. We detect a velocity dipole of high-velocity absorption at low/high galactic latitudes that we associate with LG gas that streams to the LG barycenter. This scenario is supported by the gas kinematics predicted from the LG simulations. Our study confirms previous results, indicating that the Milky Way CGM contains sufficient gaseous material to feed the Milky Way disk over the next Gyr at a rate of a few solar masses per year, if the CGM gas can actually reach the MW disk. We demonstrate that the CGM is composed of discrete gaseous structures that exhibit a large-scale kinematics together with small-scale variations in physical conditions. The MS clearly dominates both the cross section and mass flow of high-velocity gas in the Milky Way's CGM. The possible presence of high-velocity LG gas underlines the important role of the local cosmological environment in the large-scale gas-circulation processes in and around the Milky Way.
- ID:
- ivo://CDS.VizieR/J/A+A/590/A68
- Title:
- AGN data and absorption-line measurements
- Short Name:
- J/A+A/590/A68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Doubly ionized silicon (SiIII) is a powerful tracer of diffuse ionized gas inside and outside of galaxies.It can be observed in the local Universe in ultraviolet (UV) absorption against bright extragalactic background sources. We here present an extensive study of intervening SiIII-selected absorbers and study the properties of the warm circumgalactic medium (CGM) around low-redshift (z<0.1) galaxies. We analyzed the UV absorption spectra of 303 extragalactic background sources, as obtained with the Cosmic Origins Spectrograph (COS) on-board the Hubble Space Telescope (HST). We developed a geometrical model for the absorption-cross section of the CGM around the local galaxy population and compared the observed SiIII absorption statistics with predictions provided by the model. We also compared redshifts and positions of the absorbers with those of ~64,000 galaxies using archival galaxy-survey data to investigate the relation between intervening SiIII absorbers and the CGM. Along a total redshift path of {Delta}z~24, we identify 69 intervening SiIII systems that all show associated absorption from other low and high ions (e.g., HI, SiII, SiIV, CII, CIV). We derive a bias-corrected number density of dN/dz(SiIII)=2.5+/-0.4 for absorbers with column densities log N(SiIII)>12.2, which is ~3 times the number density of strong MgII systems at z=0. This number density matches the expected cross section of a SiIII absorbing CGM around the local galaxy population with a mean covering fraction of <f_c_>=0.69. For the majority (~60 percent) of the absorbers, we identify possible host galaxies within 300km/s of the absorbers and derive impact parameters {rho}<200kpc, demonstrating that the spatial distributions of SiIII absorbers and galaxies are highly correlated. Our study indicates that the majority of SiIII-selected absorbers in our sample trace the CGM of nearby galaxies within their virial radii at a typical covering fraction of ~70 percent. We estimate that diffuse gas in the CGM around galaxies, as traced by SiIII contains substantially more (more than twice as much) baryonic mass than their neutral interstellar medium.
