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641. Properties of the SUPER targets
ID:
ivo://CDS.VizieR/J/A+A/620/A82
Title:
Properties of the SUPER targets
Short Name:
J/A+A/620/A82
Date:
21 Oct 2021
Publisher:
CDS
Description:
Theoretical models of galaxy formation suggest that the presence of an active galactic nucleus (AGN) is required to regulate the growth of its host galaxy through feedback mechanisms, produced by, for example, AGN-driven outflows. Although many observational studies have revealed that such outflows are common both at low and high redshift, a comprehensive picture is still missing. In particular, the peak epoch of galaxy assembly (1<z<3) has been poorly explored so far, and current observations in this redshift range are mostly limited to targets with high chances to be in an outflowing phase. This paper introduces SUPER (a SINFONI Survey for Unveiling the Physics and Effect of Radiative feedback), an ongoing ESO's VLT/SINFONI Large Programme. SUPER will perform the first systematic investigation of ionized outflows in a sizeable and blindly-selected sample of 39 X-ray AGN at z~2, which reaches high spatial resolutions (~2kpc) thanks to the adaptive optics-assisted IFS observations. The outflow morphology and star formation in the host galaxy will be mapped through the broad component of [OIII]5007 and the narrow component of H{alpha} emission lines. The main aim of our survey is to infer the impact of outflows on the on-going star formation and to link the outflow properties to a number of AGN and host galaxy properties. We describe here the survey characteristics and goals, as well as the selection of the target sample. Moreover, we present a full characterization of its multi-wavelength properties: we measure, via spectral energy distribution fitting of UV-to-FIR photometry, stellar masses (4x10^9^-2x10^11^M_{sun}_), star formation rates (25-680M_{sun}/yr) and AGN bolometric luminosities (2x10^44^-8x10^47^erg/s), along with obscuring column densities (up to 2x10^24^cm^-2^) and luminosities in the hard 2-10keV band (2x10^43^-6x10^45^erg/s) derived through X-ray spectral analysis. Finally, we classify our AGN as jetted or non-jetted according to their radio and FIR emission.
642. Properties of weak emission-line QSOs (WLQ)
ID:
ivo://CDS.VizieR/J/ApJ/696/580
Title:
Properties of weak emission-line QSOs (WLQ)
Short Name:
J/ApJ/696/580
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Chandra observations of nine high-redshift quasars (z=2.7-5.9) discovered by the Sloan Digital Sky Survey with weak or undetectable high-ionization emission lines in their UV spectra (WLQs). Adding archival X-ray observations of six additional sources of this class has enabled us to place the strongest constraints yet on the X-ray properties of this remarkable class of active galactic nuclei (AGNs). Although our data cannot rule out the possibility that the emission lines are overwhelmed by a relativistically boosted continuum, as manifested by BL Lac objects, we find that WLQs are considerably weaker in the X-ray and radio bands than the majority of BL Lacs found at much lower redshifts. If WLQs are high-redshift BL Lacs, then it is difficult to explain the lack of a large parent population of X-ray and radio bright weak-lined sources at high redshift. We also consider the possibility that WLQs are quasars with extreme properties, and in particular that the emission lines are suppressed by high accretion rates. Using joint spectral fitting of the X-ray spectra of 11 WLQs, we find that the mean photon index in the hard X-ray band is consistent with those observed in typical radio-quiet AGNs with no hint of an unusually steep hard-X-ray spectrum. This result poses a challenge to the hypothesis that WLQs have extremely high accretion rates, and we discuss additional observations required to test this idea.
643. Properties of X-ray selected AGNs
ID:
ivo://CDS.VizieR/J/A+A/525/A127
Title:
Properties of X-ray selected AGNs
Short Name:
J/A+A/525/A127
Date:
21 Oct 2021
Publisher:
CDS
Description:
There is mounting evidence that active galactic nuclei (AGN) selected through optical emission lines or radio luminosities comprise two distinct AGN populations, whose activity is triggered by different processes. In two previous papers, we studied the host galaxies and environment of radio-loud AGN. In this third paper we study the properties of a sample of Type-2 AGN that were selected on the basis of their [2-10]keV X-ray luminosity. We find that the X-ray luminosity function is in good agreement with previous studies and that the fraction of galaxies hosting an X-ray AGN is a strong function of the stellar mass of the host galaxy. The shape of this fraction-mass relation is similar to the fraction of galaxies that are emission-line AGN, while it differs significantly from the relation observed for radio-selected AGN. The AGN in our sample tend to be located in underdense environments where galaxy mergers and interactions are likely to occur. For all host galaxy masses, the Type-2 AGN display a strong infrared excess at short (~3.5um) wavelengths, suggesting the presence of hot dust possibly associated with a hot dusty torus. These results add weight to the belief that the X-ray selection criteria identifies a population of AGN similar to the emission-line selected population but distinct from the radio population at high masses.
644. Proton synchrotron gamma-rays in blazars
ID:
ivo://CDS.VizieR/J/ApJ/893/L20
Title:
Proton synchrotron gamma-rays in blazars
Short Name:
J/ApJ/893/L20
Date:
21 Oct 2021
Publisher:
CDS
Description:
The origin of high-energy emission in blazars jets (i.e., leptonic versus hadronic) has been a longstanding matter of debate. Here, we focus on one variant of hadronic models where proton synchrotron radiation accounts for the observed steady {gamma}-ray blazar emission. Using analytical methods, we derive the minimum jet power (P_j,min_) for the largest blazar sample analyzed to date (145 sources), taking into account uncertainties of observables and jet's physical parameters. We compare P_j,min_ against three characteristic energy estimators for accreting systems, i.e., the Eddington luminosity, the accretion disk luminosity, and the power of the Blandford-Znajek process, and find that P_j,min_ is about 2 orders of magnitude higher than all energetic estimators for the majority of our sample. The derived magnetic field strengths in the emission region require either large amplification of the jet's magnetic field (factor of 30) or place the {gamma}-ray production site at sub-pc scales. The expected neutrino emission peaks at ~0.1-10EeV, with typical peak neutrino fluxes ~10^-4^ times lower than the peak {gamma}-ray fluxes. We conclude that if relativistic hadrons are present in blazar jets, they can only produce a radiatively subdominant component of the overall spectral energy distribution of the blazar's steady emission.
645. QSO Candidates in the MACHO LMC database
ID:
ivo://CDS.VizieR/J/ApJ/747/107
Title:
QSO Candidates in the MACHO LMC database
Short Name:
J/ApJ/747/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog the 2566 QSO candidates in the MACHO LMC database. In these catalogs, we complied number of properties of the objects including RA, Dec, crossmatched IDs with several catalogs, magnitudes, photometric redshifts, etc. See Kim et al. (2011ApJ...735...68K) for the SVM (a.k.a. Support Vector Machine, a supervised machine learning algorithm) QSO classification model based on the time variability of lightcurves. We used the model to select the 2566 QSO candidates. In this work, we employed multiple diagnostics such as X-ray flux, mid-IR color and AGN SED fitting in order to select 663 promising QSO candidates among the 2,566 candidates. These candidates are flagged in the catalog. We calibrated the MACHO RA and Dec of the candidates using the UCAC3 catalog and improved the average astrometric accuracy from ~3" to ~0.5".
646. QSO J1538+0855 MUSE datacube
ID:
ivo://CDS.VizieR/J/A+A/635/A157
Title:
QSO J1538+0855 MUSE datacube
Short Name:
J/A+A/635/A157
Date:
21 Oct 2021
Publisher:
CDS
Description:
In recent years, Ly{alpha} nebulae have been routinely detected around high redshift, radio-quiet quasars thanks to the advent of the highly sensitive integral field spectrographs. Constraining the physical properties of the Ly{alpha} nebulae is crucial for a full understanding of the circum-galactic medium (CGM). The CGM acts both as a repository for intergalactic and galactic baryons as well as a venue of feeding and feedback processes. The most luminous quasars are privileged test-beds to study these processes, given their large ionising fluxes and dense CGM environments in which they are expected to be embedded.We aim to characterise the rest-frame ultraviolet (UV) emission lines in the CGM around a hyper-luminous, broad emission line, radio-quiet quasar at z~3.6, which exhibits powerful outflows at both nuclear and host galaxy scales.We analyse VLT/MUSE observations of the quasar J1538+08 (Lbol=6*10^47^erg/s), and we performed a search for extended UV emission lines to characterise its morphology, emissivity, kinematics, and metal content.We report the discovery of a very luminous (2*10^44^erg/s), giant (150kpc) Ly{alpha} nebula and a likely associated extended (75kpc) CIV nebula. The Ly{alpha} nebula emission exhibits moderate blueshift (440km/s) compared to the quasar systemic redshift and a large average velocity dispersion (700km/s) across the nebula, while the CIV nebula shows average velocity dispersion of 350km/s. The Ly{alpha} line profile exhibits a significant asymmetry towards negative velocity values at 20-30kpc south of the quasar and is well parametrised by the following two Gaussian components: a narrow (470km/s) systemic one plus a broad (1200km/s), blueshifted (1500km/s) one. Our analysis of the MUSE observation of J1538+08 reveals metal-enriched CGM around this hyper-luminous quasar. Furthermore, our detection of blueshifted emission in the emission profile of the Ly{alpha} nebula suggests that powerful nuclear outflows can propagate through the CGM over tens of kiloparsecs.
647. QSO properties from SDSS-DR7
ID:
ivo://CDS.VizieR/J/ApJS/194/45
Title:
QSO properties from SDSS-DR7
Short Name:
J/ApJS/194/45
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a compilation of properties of the 105783 quasars in the Sloan Digital Sky Survey Data Release 7 (DR7) quasar catalog (Cat. VII/260). In this product, we compile continuum and emission line measurements around the H{alpha}, H{beta}, MgII, and CIV regions, as well as other quantities such as radio properties, and flags indicating broad absorption line quasars, disk emitters, etc. We also compile virial black hole mass estimates based on various calibrations. For the fiducial virial mass estimates we use the Vestergaard & Peterson (VP06; 2006ApJ...641..689V) calibrations for H{beta} and CIV, and our own calibration for MgII which matches the VP06 H{beta} masses on average. We describe the construction of this catalog and discuss its limitations.
648. QSOs in the M3 field
ID:
ivo://CDS.VizieR/J/A+A/392/851
Title:
QSOs in the M3 field
Short Name:
J/A+A/392/851
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from a variability and proper motion (VPM) search for QSOs in the field around M3. The VPM search is demonstrated to be powerful technique for efficiently finding QSOs without major selection effects with regard to the spectral energy distribution. Remarkably, the properties of the VPM QSOs do not significantly differ from those of samples from more conventional optical search techniques. The lightcurves of the QSOs from the resulting sample provide an interesting data set for the statistical investigation of QSO long-term variability.
649. QSOs properties
ID:
ivo://CDS.VizieR/J/ApJ/625/78
Title:
QSOs properties
Short Name:
J/ApJ/625/78
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the properties of infrared-selected QSOs (IR QSOs), optically selected Palomar-Green QSOs (PG QSOs), and narrow-line Seyfert 1 galaxies (NLS1s). We compare their properties from the IR to the optical and examine various correlations among the black hole mass, accretion rate, star formation rate, and optical and IR luminosities.
650. Quasar black hole masses
ID:
ivo://CDS.VizieR/J/ApJ/669/791
Title:
Quasar black hole masses
Short Name:
J/ApJ/669/791
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the time-dependent variations of ultraviolet (UV) black hole mass estimates of quasars in the Sloan Digital Sky Survey (SDSS). From SDSS spectra of 615 high-redshift (1.69<z<4.75) quasars with spectra from two epochs, we estimate black hole masses using a single-epoch technique, which employs an additional, automated night-sky line removal and relies on UV continuum luminosity and CIV {lambda}1549 emission-line dispersion. Mass estimates show variations between epochs at about the 30% level for the sample as a whole. We determine that for our full sample, measurement error in the line dispersion likely plays a larger role than the inherent variability in terms of contributing to variations in mass estimates between epochs. However, we use the variations in quasars with r-band spectral signal-to-noise ratio greater than 15 to estimate that the contribution to these variations from inherent variability is roughly 20%. We conclude that these differences in black hole mass estimates between epochs indicate that variability does not make a large contribution to the current factor of 2 scatter between mass estimates derived from low- and high-ionization emission lines.