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111. A uniformly selected, all-sky, optical AGN catalog
ID:
ivo://CDS.VizieR/J/ApJ/872/134
Title:
A uniformly selected, all-sky, optical AGN catalog
Short Name:
J/ApJ/872/134
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have constructed an all-sky catalog of optical active galactic nuclei (AGNs) with z<0.09, based on optical spectroscopy, from the parent sample of galaxies in the 2MASS Redshift Survey, a near-complete census of the nearby universe. Our catalog consists of 1929 broad-line AGNs and 6562 narrow-line AGNs that satisfy the Kauffmann et al. (2003MNRAS.346.1055K) criteria, of which 3607 also satisfy the Kewley et al. (2006MNRAS.372..961K) criteria. We also report emission-line widths, fluxes, flux errors, and signal-to-noise ratios (S/Ns) of all the galaxies in our spectroscopic sample, allowing users to customize the selection criteria. Although we uniformly processed the spectra of galaxies from a homogeneous parent sample, inhomogeneities persist owing to the differences in the quality of the obtained spectra, taken with different instruments, and the unavailability of spectra for ~20% of the galaxies. We quantify how the differences in spectral quality affect not only the AGN detection rates but also ratios of broad-line to narrow-line AGNs. We find that the inhomogeneities primarily stem from the continuum S/N in the spectra near the emission lines of interest. We fit for the AGN fraction as a function of continuum S/N and assign AGN likelihoods to galaxies that were not identified as AGNs using the available spectra. This correction results in a catalog suitable for statistical studies. This work also paves the way for a truly homogeneous and complete nearby AGN catalog by identifying galaxies whose AGN status needs to be verified with higher-quality spectra, quantifying the spectral quality necessary to do so.
112. A 10yr reverberation mapping campaign for 3C273
ID:
ivo://CDS.VizieR/J/ApJ/876/49
Title:
A 10yr reverberation mapping campaign for 3C273
Short Name:
J/ApJ/876/49
Date:
21 Oct 2021
Publisher:
CDS
Description:
Despite many decades of study, the kinematics of the broad-line region of 3C 273 are still poorly understood. We report a new, high signal-to-noise, reverberation mapping campaign carried out from 2008 November to 2018 March that allows the determination of time lags between emission lines and the variable continuum with high precision. The time lag of variations in H{beta} relative to those of the 5100{AA} continuum is 146.8_-12.1_^+8.3^days in the rest frame, which agrees very well with the Paschen-{alpha} region measured by the GRAVITY at The Very Large Telescope Interferometer. The time lag of the H{gamma} emission line is found to be nearly the same as that for H{beta}. The lag of the FeII emission is 322.0_-57.9_^+55.5^days, longer by a factor of ~2 than that of the Balmer lines. The velocity-resolved lag measurements of the H{beta} line show a complex structure that can be possibly explained by a rotation-dominated disk with some inflowing radial velocity in the H{beta}-emitting region. Taking the virial factor of f_BLR_=1.3, we derive a BH mass of dM/dt=4.1_-0.4_^+0.3^x10^8^M_{sun}_ and an accretion rate of 9.3L_Edd_c^-2^ from the H{beta} line. The decomposition of its Hubble Space Telescope images yields a host stellar mass of M*=10^11.3+/-0.7^M_{sun}_, and a ratio of dM/dt/M*~2.0x10^-3^ in agreement with the Magorrian relation. In the near future, it is expected to compare the geometrically thick BLR discovered by the GRAVITY in 3C 273 with its spatially resolved torus in order to understand the potential connection between the BLR and the torus.
113. BAL QSOs in SDSS-DR5
ID:
ivo://CDS.VizieR/J/ApJ/692/758
Title:
BAL QSOs in SDSS-DR5
Short Name:
J/ApJ/692/758
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 5039 broad absorption line (BAL) quasars (QSOs) in the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) QSO catalog that have absorption troughs covering a continuous velocity range >=2000km/s. We have fitted ultraviolet (UV) continua and line emission in each case, enabling us to report common diagnostics of BAL strengths and velocities in the range -25000 to 0km/s for SiIV1400, CIV1549, AlIII1857, and MgII2799. We calculate these diagnostics using the spectrum listed in the DR5 QSO catalog, and also for spectra from additional SDSS observing epochs when available. In cases where BAL QSOs have been observed with Chandra or XMM-Newton, we report the X-ray monochromatic luminosities of these sources. We confirm and extend previous findings that BAL QSOs are more strongly reddened in the rest-frame UV than non-BAL QSOs, and that BAL QSOs are relatively X-ray weak compared to non-BAL QSOs.
114. BAT AGN spectroscopic survey. XI. IR photometry
ID:
ivo://CDS.VizieR/J/ApJ/870/31
Title:
BAT AGN spectroscopic survey. XI. IR photometry
Short Name:
J/ApJ/870/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
We quantify the luminosity contribution of active galactic nuclei (AGNs) to the 12{mu}m, mid-infrared (MIR; 5-38{mu}m), and total IR (5-1000{mu}m) emission in the local AGNs detected in the all-sky 70 month Swift/Burst Alert Telescope (BAT) ultrahard X-ray survey. We decompose the IR spectral energy distributions (SEDs) of 587 objects into the AGN and starburst components using templates for an AGN torus and a star-forming galaxy. This enables us to recover the emission from the AGN torus including the low-luminosity end, down to log(L_14-150_/erg/s)~41, which typically has significant host galaxy contamination. The sample demonstrates that the luminosity contribution of the AGN to the 12{mu}m, the MIR, and the total IR bands is an increasing function of the 14-150keV luminosity. We also find that for the most extreme cases, the IR pure-AGN emission from the torus can extend up to 90{mu}m. The total IR AGN luminosity obtained through the IR SED decomposition enables us to estimate the fraction of the sky obscured by dust, i.e., the dust covering factor. We demonstrate that the median dust covering factor is always smaller than the median X-ray obscuration fraction above an AGN bolometric luminosity of log(L_bol_^(AGN)^/erg/s)~42.5. Considering that the X-ray obscuration fraction is equivalent to the covering factor coming from both the dust and gas, this indicates that an additional neutral gas component, along with the dusty torus, is responsible for the absorption of X-ray emission.
115. BAT AGN spectroscopic survey. XVI. Blazars
ID:
ivo://CDS.VizieR/J/ApJ/881/154
Title:
BAT AGN spectroscopic survey. XVI. Blazars
Short Name:
J/ApJ/881/154
Date:
21 Oct 2021
Publisher:
CDS
Description:
The recently released 105-month Swift-Burst Alert Telescope (BAT) all-sky hard X-ray survey catalog presents an opportunity to study astrophysical objects detected in the deepest look at the entire hard X-ray (14-195keV) sky. Here we report the results of a multifrequency study of 146 blazars from this catalog, quadrupling the number compared to past studies, by utilizing recent data from the Fermi-Large Area Telescope (LAT), Swift-BAT, and archival measurements. In our {gamma}-ray analysis of ~10yr of the LAT data, 101 are found as {gamma}-ray emitters, whereas, 45 remains LAT undetected. We model the broadband spectral energy distributions with a synchrotron-inverse Compton radiative model. On average, BAT detected sources host massive black holes (M_bh_~10^9^M_{sun}_) and luminous accretion disks (L_d_~10^46^erg/s). At high redshifts (z>2), BAT blazars host more powerful jets with luminous accretion disks compared to those detected only with Fermi-LAT. We find good agreement in the black hole masses derived from the single-epoch optical spectroscopic measurements and standard accretion disk modeling approaches. Other physical properties of BAT blazars are similar to those known for Fermi-LAT detected objects.
116. BAT AGN Spectroscopic Survey. XVIII. Periodic var.
ID:
ivo://CDS.VizieR/J/ApJ/896/122
Title:
BAT AGN Spectroscopic Survey. XVIII. Periodic var.
Short Name:
J/ApJ/896/122
Date:
03 Dec 2021 13:15:09
Publisher:
CDS
Description:
Theory predicts that a supermassive black hole binary (SMBHB) could be observed as a luminous active galactic nucleus (AGN) that periodically varies on the order of its orbital timescale. In X-rays, periodic variations could be caused by mechanisms including relativistic Doppler boosting and shocks. Here we present the first systematic search for periodic AGNs using 941 hard X-ray light curves (14-195keV) from the first 105 months of the Swift Burst Alert Telescope (BAT) survey (2004-2013). We do not find evidence for periodic AGNs in Swift-BAT, including the previously reported SMBHB candidate MCG+11-11-032. We find that the null detection is consistent with the combination of the upper-limit binary population in AGNs in our adopted model, their expected periodic variability amplitudes, and the BAT survey characteristics. We have also investigated the detectability of SMBHBs against normal AGN X-ray variability in the context of the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) survey. Under our assumptions of a binary population and the periodic signals they produce, which have long periods of hundreds of days, up to 13% true periodic binaries can be robustly distinguished from normal variable AGNs with the ideal uniform sampling. However, we demonstrate that realistic eROSITA sampling is likely to be insensitive to long-period binaries because longer observing gaps reduce their detectability. In contrast, large observing gaps do not diminish the prospect of detecting binaries of short, few-day periods, as 19% can be successfully recovered, the vast majority of which can be identified by the first half of the survey.
117. BAT AGN Spectroscopic Survey. XX. Molecular gas
ID:
ivo://CDS.VizieR/J/ApJS/252/29
Title:
BAT AGN Spectroscopic Survey. XX. Molecular gas
Short Name:
J/ApJS/252/29
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the host-galaxy molecular gas properties of a sample of 213 nearby (0.01<z<0.05) hard-X-ray-selected active galactic nucleus (AGN) galaxies, drawn from the 70-month catalog of Swift's Burst Alert Telescope (BAT), with 200 new CO(2-1) line measurements obtained with the James Clerk Maxwell Telescope and the Atacama Pathfinder Experiment telescope. We find that AGN in massive galaxies (log(M_*_/M_{sun}_)>10.5) tend to have more molecular gas and higher gas fractions than inactive galaxies matched in stellar mass. When matched in star formation, we find AGN galaxies show no difference from inactive galaxies, with no evidence that AGN feedback affects the molecular gas. The higher molecular gas content is related to AGN galaxies hosting a population of gas-rich early types with an order of magnitude more molecular gas and a smaller fraction of quenched, passive galaxies (~5% versus 49%) compared to inactive galaxies. The likelihood of a given galaxy hosting an AGN (L_bol_>10^44^erg/s) increases by ~10-100 between a molecular gas mass of 10^8.7^M_{sun}_ and 10^10.2^M_{sun}_. AGN galaxies with a higher Eddington ratio (log(L/L_Edd_)>-1.3) tend to have higher molecular gas masses and gas fractions. The log(NH/cm^-2^)>23.4) of AGN galaxies with higher column densities are associated with lower depletion timescales and may prefer hosts with more gas centrally concentrated in the bulge that may be more prone to quenching than galaxy-wide molecular gas. The significant average link of host-galaxy molecular gas supply to supermassive black hole (SMBH) growth may naturally lead to the general correlations found between SMBHs and their host galaxies, such as the correlations between SMBH mass and bulge properties, and the redshift evolution of star formation and SMBH growth.
118. BAT X-ray survey. I.
ID:
ivo://CDS.VizieR/J/ApJ/678/102
Title:
BAT X-ray survey. I.
Short Name:
J/ApJ/678/102
Date:
21 Oct 2021
Publisher:
CDS
Description:
We applied the maximum likelihood (ML) method, as an image reconstruction algorithm, to the BAT (Burst Alert Telescope) X-Ray Survey (BXS). This method was specifically designed to preserve the full statistical information in the data and to avoid mosaicking of many exposures with different pointing directions, thus reducing systematic errors when co-adding images. We reconstructed, in the 14-170keV energy band, the image of a 90x90deg^2^ sky region, centered on (RA, DE)=(105{deg}, -25{deg}), which BAT surveyed with an exposure time of ~1Ms (in 2005 November). The best sensitivity in our image is ~0.85mCrab or 2.0x10^-11^ergs/cm^2^. We detect 49 hard X-ray sources above the 4.5{sigma} level; of these, only 12 were previously known as hard X-ray sources (>15keV). Swift XRT observations allowed us to firmly identify the counterparts for 15 objects, while 2 objects have Einstein IPC counterparts (Harris et al., 1990, in Imaging X-Ray Astronomy. A Decade of Achievements, ed. M. Elvis (Cambridge: Cambridge Univ. Press), 309); in addition to those, we found a likely counterpart for 13 objects by correlating our sample with the ROSAT All-Sky Survey Bright Source Catalog (Voges et al., 1999, Cat. <IX/10>). Seven objects remain unidentified.
119. BCGs with radio AGN
ID:
ivo://CDS.VizieR/J/ApJ/704/1586
Title:
BCGs with radio AGN
Short Name:
J/ApJ/704/1586
Date:
21 Oct 2021
Publisher:
CDS
Description:
The radio active galactic nucleus (AGN) feedback in X-ray cool cores has been proposed as a crucial ingredient in the evolution of baryonic structures. However, it has long been known that strong radio AGNs also exist in "noncool core" clusters, which brings up the question whether an X-ray cool core is always required for the radio feedback. In this work, we present a systematic analysis of brightest cluster galaxies (BCGs) and strong radio AGNs in 152 groups and clusters from the Chandra archive. All 69 BCGs with radio AGN more luminous than 2x10^23^W/Hz at 1.4GHz are found to have X-ray cool cores. BCG cool cores can be divided into two classes: the large cool core (LCC) class and the corona class. As examples of the corona class, we also present detailed analyses of a BCG corona associated with a strong radio AGN (ESO 137-006 in A3627) and one of the faintest coronae known (NGC 4709 in the Centaurus cluster).
120. Beamed and unbeamed emission of gamma-ray blazars
ID:
ivo://CDS.VizieR/J/PASP/132/K4102
Title:
Beamed and unbeamed emission of gamma-ray blazars
Short Name:
J/PASP/132/K4102
Date:
21 Oct 2021
Publisher:
CDS
Description:
A two-component model of radio emission has been used to explain some radio observational properties of Active Galactic Nuclei (AGNs) and, in particular, of blazars. In this work, we extend the two-component idea to the {gamma}-ray emission and assume that the total {gamma}-ray output of blazars consists of relativistically beamed and unbeamed components. The basic idea leverages the correlation between the radio core-dominance parameter and the {gamma}-ray beaming factor. To do so, we evaluate this correlation for a large sample of 584 blazars taken from the fourth source catalog of the Fermi Large Area Telescope (Fermi-LAT) and correlated their {gamma}-ray core-dominance parameters with radio core-dominance parameters. The {gamma}-ray beaming factor is then used to estimate the beamed and unbeamed components. Our analysis confirms that the {gamma}-ray emission in blazars is mainly from the beamed component.