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121. WISE MIR variability in gamma-ray Seyfert 1 gal.
ID:
ivo://CDS.VizieR/J/ApJS/255/10
Title:
WISE MIR variability in gamma-ray Seyfert 1 gal.
Short Name:
J/ApJS/255/10
Date:
11 Mar 2022
Publisher:
CDS
Description:
Fermi-LAT's detection of {gamma}-rays from narrow-line Seyfert 1 galaxies (NLS1s) has received increasing attention. Understanding these {gamma}-NLS1s is of interest because they have some properties similar to blazars, which are known to show rapid and large-amplitude variability. Based on the largest sample of {gamma}-NLS1s (25 sources), we carried out a systematic search for rapid mid-infrared (MIR, 3.4 and 4.6{mu}m) variability using the multiepoch data of the Wide-field Infrared Survey Explorer (WISE). We also compared a few variability properties between {gamma}-NLS1s and {gamma}-ray blazars. Our main results are as follows. (1) Thirteen {gamma}-NLS1s showed significant (>3{sigma}) rapid variability in at least one of the two MIR bands. The MIR emission of these sources is dominated by the synchrotron emission of relativistic electrons in the jet. (2) The {gamma}-NLS1s with flat radio spectra are more variable than those not detected in {gamma}-rays. (3) The {gamma}-NLS1s tend to show smaller amplitude of variability as well as lower duty cycle relative to {gamma}-ray blazars. (4) The {gamma}-NLS1s tend to show a trend of bluer-when-brighter on both intraday and long timescales, similar to {gamma}-ray blazars. (5) The {gamma}-NLS1s that are more variable on long timescales have larger amplitudes of variability and higher duty cycles on intraday timescales. (6) In the majority of cases, the {gamma}-NLS1s fall in the WISE Gamma-ray Blazar Strip (WGS). However, we noted migrations outside of the WGS due to significant variability.
122. X-ray absorption in INTEGRAL AGN
ID:
ivo://CDS.VizieR/J/A+A/639/A5
Title:
X-ray absorption in INTEGRAL AGN
Short Name:
J/A+A/639/A5
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this work the INTEGRAL hard X-ray selected sample of AGN has been used to investigate the possible contribution of absorbing material distributed within the host galaxies to the total amount of NH measured in the X-ray band. We collected all the available axial ratio measurements of the galaxies hosting our AGN together with their morphological information and find that also for our hard X-ray selected sample a deficit of edge-on galaxies hosting type 1 AGN is present. We estimate that in our hard X-ray selected sample there is a deficit of 24% (+/-5%) of type 1 AGN. Possible bias in redshift has been excluded, as we found the same effect in a well determined range of z where the number and the distributions of the two classes are statistically the same. Our findings clearly indicate that material located in the host galaxy on scales of hundreds of parsecs and not aligned with the putative absorbing torus of the AGN can contribute to the total amount of column density. This galactic absorber can be large enough to hide the broad line region of some type 1 AGN causing their classification as type 2 objects and giving rise to the deficiency of type 1 in edge-on galaxies.
123. X-ray obs. of narrow- and broad-line Seyfert 1 gal.
ID:
ivo://CDS.VizieR/J/ApJ/896/95
Title:
X-ray obs. of narrow- and broad-line Seyfert 1 gal.
Short Name:
J/ApJ/896/95
Date:
03 Dec 2021 00:52:46
Publisher:
CDS
Description:
We present a detailed comparative systematic study using a sample of 221 narrow-line Seyfert 1 (NLSy1) galaxies in comparison to a redshift-matched sample of 154 broad-line Seyfert 1 (BLSy1) galaxies based on their observations using ROSAT and/or XMM-Newton in soft X-ray band (0.1-2.0keV). A homogeneous analysis is carried out to estimate their soft X-ray photon indices ({Gamma}_X_^s^) and its correlations with other parameters of nuclear activities such as Eddington ratios (REdd), bolometric luminosities (Lbol), black hole masses (MBH), and the widths of the broad component of H{beta} lines (FWHM(H{beta})). In our analysis, we found clear evidence of the difference in the {Gamma}_X_^s^ and R_Edd_ distributions among NLSy1 and BLSy1 galaxies, with steeper {Gamma}_X_^s^ and higher R_Edd_ for the former. Such a difference also exists in the spectral index distribution in hard X-ray ({Gamma}_X_^h^), based on the analysis of 53 NLSy1 and 46 BLSy1 galaxies in the 2-10keV energy band. The difference in REdd distributions does exist even after applying the average correction for the difference in the inclination angle of NLSy1 and BLSy1 galaxies. We also estimated R_Edd_, based on SED fitting of 34 NLSy1 and 30 BLSy1 galaxies over the 0.3-10keV energy band, and found that results are still consistent with REdd estimates based on the optical bolometric luminosity. Our analysis suggests that the higher REdd in NLSy1 is responsible for its steeper X-ray spectral slope compared to the BLSy1, consistent with the disk-corona model as proposed for the luminous AGNs.
124. X-ray of active galaxies and nuclei
ID:
ivo://CDS.VizieR/VII/181
Title:
X-ray of active galaxies and nuclei
Short Name:
VII/181
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
125. X-ray properties of Seyfert 1 galaxies
ID:
ivo://CDS.VizieR/J/ApJ/713/L11
Title:
X-ray properties of Seyfert 1 galaxies
Short Name:
J/ApJ/713/L11
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use publicly available XMM-Newton data to systematically compare the hard X-ray photon indices, {Gamma}_2-10keV_, and the iron K{alpha} emission lines of narrow- and broad-line Seyfert 1 (NLS1 and BLS1) galaxies. We compile a flux-limited (f_2-10keV_>=1x10^-12^erg/s/cm^2^) sample including 114 radio-quiet objects, with the 2-10keV luminosity ranging from 10^41^ to 10^45^erg/s. 86 out of these 114 AGNs are included in the CAIXA catalogue (Bianchi et al. 2009, Cat. J/A+A/495/421). The redshift range of the present sample is z<0.37, with only seven objects having z>0.2.
126. X-ray sources <1 degree from Seyfert galaxies
ID:
ivo://CDS.VizieR/J/A+A/319/18
Title:
X-ray sources <1 degree from Seyfert galaxies
Short Name:
J/A+A/319/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
Archived PSPC observations of 26 Seyfert galaxies have been analyzed for bright X-ray sources out to the full extent of the field (< about 50'). Of all Seyferts known this represents a sample 88% complete to B_T_=10mag, 74% complete to 11mag and 50% complete to 12mag. Using the same reduction algorithm, 14 fields centered on stars at high galactic latitudes have been used as control fields. Excluding the two brightest Seyferts, a subset of 24 Seyferts with corrected apparent magnitude between 8.04<B^o,i^_T_<12.90mag show a minimum excess of 46 bright X-ray sources generally distributed between 10 and 25' from the target galaxy. The significances of association of these sources with the Seyferts in the median brightness range are as high as 7.4-sigma.
127. X-ray sources in the AKARI NEP deep field
ID:
ivo://CDS.VizieR/J/MNRAS/446/911
Title:
X-ray sources in the AKARI NEP deep field
Short Name:
J/MNRAS/446/911
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present data products from the 300ks Chandra survey in the AKARI North Ecliptic Pole (NEP) deep field. This field has a unique set of 9-band infrared photometry covering 2-24 micron from the AKARI Infrared Camera, including mid-infrared (MIR) bands not covered by Spitzer. The survey is one of the deepest ever achieved at ~15 micron, and is by far the widest among those with similar depths in the MIR. This makes this field unique for the MIR-selection of AGN at z~1. We design a source detection procedure, which performs joint Maximum Likelihood PSF fits on all of our 15 mosaicked Chandra pointings covering an area of 0.34 square degree. The procedure has been highly optimized and tested by simulations. We provide a point source catalog with photometry and Bayesian-based 90 per cent confidence upper limits in the 0.5-7, 0.5-2, 2-7, 2-4, and 4-7keV bands. The catalog contains 457 X-ray sources and the spurious fraction is estimated to be ~1.7 per cent. Sensitivity and 90 per cent confidence upper flux limits maps in all bands are provided as well. We search for optical MIR counterparts in the central 0.25 square degree, where deep Subaru Suprime-Cam multiband images exist. Among the 377 X-ray sources detected there, ~80 per cent have optical counterparts and ~60 per cent also have AKARI mid-IR counterparts. We cross-match our X-ray sources with MIR-selected AGN from Hanami et al. Around 30 per cent of all AGN that have MID-IR SEDs purely explainable by AGN activity are strong Compton-thick AGN candidates.

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