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17801. X-ray observations of HCG galaxies
ID:
ivo://CDS.VizieR/J/ApJ/817/95
Title:
X-ray observations of HCG galaxies
Short Name:
J/ApJ/817/95
Date:
21 Oct 2021
Publisher:
CDS
Description:
We obtain total galaxy X-ray luminosities, L_X_, originating from individually detected point sources in a sample of 47 galaxies in 15 compact groups of galaxies (CGs). For the great majority of our galaxies, we find that the detected point sources most likely are local to their associated galaxy, and are thus extragalactic X-ray binaries (XRBs) or nuclear active galactic nuclei (AGNs). For spiral and irregular galaxies, we find that, after accounting for AGNs and nuclear sources, most CG galaxies are either within the +/-1{sigma} scatter of the Mineo et al. L_X_-star formation rate (SFR) correlation or have higher L_X_ than predicted by this correlation for their SFR. We discuss how these "excesses" may be due to low metallicities and high interaction levels. For elliptical and S0 galaxies, after accounting for AGNs and nuclear sources, most CG galaxies are consistent with the Boroson et al. L_X_-stellar mass correlation for low-mass XRBs, with larger scatter, likely due to residual effects such as AGN activity or hot gas. Assuming non-nuclear sources are low- or high-mass XRBs, we use appropriate XRB luminosity functions to estimate the probability that stochastic effects can lead to such extreme L_X_ values. We find that, although stochastic effects do not in general appear to be important, for some galaxies there is a significant probability that high L_X_ values can be observed due to strong XRB variability.
17802. X-ray observations of NGC 2264
ID:
ivo://CDS.VizieR/J/AJ/134/999
Title:
X-ray observations of NGC 2264
Short Name:
J/AJ/134/999
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from an X-ray imaging survey of the young cluster NGC 2264, carried out with the European Photon Imaging Cameras (EPIC) on board the XMM-Newton spacecraft. The X-ray data are merged with extant optical and near-infrared photometry, spectral classifications, Halpha emission strengths, and rotation periods to examine the interrelationships between coronal and chromospheric activity, rotation, stellar mass, and internal structure for a statistically significant sample of pre-main-sequence stars. A total of 300 distinct X-ray sources can be identified with optical or near-infrared counterparts. The sources are concentrated within three regions of the cluster: in the vicinity of S Mon, within the large emission/reflection nebulosity southwest of S Mon, and along the broad ridge of molecular gas that extends from the Cone Nebula to the NGC 2264 IRS 2 field.
17803. X-ray observations of Stripe 82
ID:
ivo://CDS.VizieR/J/MNRAS/436/3581
Title:
X-ray observations of Stripe 82
Short Name:
J/MNRAS/436/3581
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have analysed the XMM-Newton and Chandra data overlapping ~16.5deg^2^ of Sloan Digital Sky Survey Stripe 82, including ~4.6deg^2^ of proprietary XMM-Newton data that we present here. In total, 3362 unique X-ray sources are detected at high significance. We derive the XMM-Newton number counts and compare them with our previously reported Chandra logN-logS relations and other X-ray surveys. The Stripe 82 X-ray source lists have been matched to multiwavelength catalogues using a maximum likelihood estimator algorithm. We discovered the highest redshift (z=5.86) quasar yet identified in an X-ray survey. We find 2.5 times more high-luminosity (L_X_>10^45erg/s) AGN than the smaller area Chandra and XMM-Newton survey of COSMOS and 1.3 times as many identified by XBootes. Comparing the high-luminosity active galactic nuclei (AGN) we have identified with those predicted by population synthesis models, our results suggest that this AGN population is a more important component of cosmic black hole growth than previously appreciated. Approximately a third of the X-ray sources not detected in the optical are identified in the infrared, making them candidates for the elusive population of obscured high-luminosity AGN in the early universe.
17804. X-ray Observations of Stripe 82
ID:
ivo://CDS.VizieR/J/ApJ/817/172
Title:
X-ray Observations of Stripe 82
Short Name:
J/ApJ/817/172
Date:
21 Oct 2021
Publisher:
CDS
Description:
We release the next installment of the Stripe 82 X-ray survey point-source catalog, which currently covers 31.3deg^2^ of the Sloan Digital Sky Survey (SDSS) Stripe 82 Legacy field. In total, 6181 unique X-ray sources are significantly detected with XMM-Newton (>5{sigma}) and Chandra (>4.5{sigma}). This catalog release includes data from XMM-Newton cycle AO 13, which approximately doubled the Stripe 82X survey area. The flux limits of the Stripe 82X survey are 8.7x10^-16^erg/s/cm2, 4.7x10^-15^erg/s/cm2, and 2.1x10^-15^erg/s/cm2 in the soft (0.5-2keV), hard (2-10keV), and full bands (0.5-10keV), respectively, with approximate half-area survey flux limits of 5.4x10^-15^erg/s/cm2, 2.9x10^-14^erg/s/cm2, and 1.7x10^-14^erg/s/cm2. We matched the X-ray source lists to available multi-wavelength catalogs, including updated matches to the previous release of the Stripe 82X survey; 88% of the sample is matched to a multi-wavelength counterpart. Due to the wide area of Stripe 82X and rich ancillary multi-wavelength data, including coadded SDSS photometry, mid-infrared WISE coverage, near-infrared coverage from UKIDSS and VISTA Hemisphere Survey, ultraviolet coverage from GALEX, radio coverage from FIRST, and far-infrared coverage from Herschel, as well as existing ~30% optical spectroscopic completeness, we are beginning to uncover rare objects, such as obscured high-luminosity active galactic nuclei at high-redshift. The Stripe 82X point source catalog is a valuable data set for constraining how this population grows and evolves, as well as for studying how they interact with the galaxies in which they live.
17805. X-ray observations of the Galaxy center
ID:
ivo://CDS.VizieR/J/MNRAS/371/38
Title:
X-ray observations of the Galaxy center
Short Name:
J/MNRAS/371/38
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Galactic centre (GC) provides a unique laboratory for a detailed examination of the interplay between massive star formation and the nuclear environment of our Galaxy. Here, we present a 100-ks Chandra Advanced CCD Imaging Spectrometer (ACIS) observation of the Arches and Quintuplet star clusters. We also report on a complementary mapping of the dense molecular gas near the Arches cluster made with the Owens Valley Millimeter Array. We present a catalogue of 244 point-like X-ray sources detected in the observation.
17806. 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.
17807. X-ray obs. of SINGS gal. compared to models
ID:
ivo://CDS.VizieR/J/ApJ/774/136
Title:
X-ray obs. of SINGS gal. compared to models
Short Name:
J/ApJ/774/136
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the largest-scale comparison to date between observed extragalactic X-ray binary (XRB) populations and theoretical models of their production. We construct observational X-ray luminosity functions (oXLFs) using Chandra observations of 12 late-type galaxies from the Spitzer Infrared Nearby Galaxy Survey. For each galaxy, we obtain theoretical XLFs (tXLFs) by combining XRB synthetic models, constructed with the population synthesis code StarTrack, with observational star formation histories (SFHs). We identify highest-likelihood models both for individual galaxies and globally, averaged over the full galaxy sample. Individual tXLFs successfully reproduce about half of the oXLFs, but for some galaxies we are unable to find underlying source populations, indicating that galaxy SFHs and metallicities are not well matched and/or that XRB modeling requires calibration on larger observational samples. Given these limitations, we find that the best models are consistent with a product of common envelope ejection efficiency and central donor concentration =~0.1, and a 50% uniform-50% "twins" initial mass-ratio distribution. We present and discuss constituent subpopulations of tXLFs according to donor, accretor, and stellar population characteristics. The galaxy-wide X-ray luminosity due to low-mass and high-mass XRBs, estimated via our best global model tXLF, follows the general trend expected from the L_X_-star formation rate and L_X_-stellar mass relations of Lehmer et al. Our best models are also in agreement with modeling of the evolution of both XRBs over cosmic time and of the galaxy X-ray luminosity with redshift.
17808. 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)
17809. X-ray, opt. & radio SEDs of Fermi blazars
ID:
ivo://CDS.VizieR/J/ApJS/226/20
Title:
X-ray, opt. & radio SEDs of Fermi blazars
Short Name:
J/ApJS/226/20
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, multiwavelength data are compiled for a sample of 1425 Fermi blazars to calculate their spectral energy distributions (SEDs). A parabolic function, log({nu}F_{nu}_)=P_1_(log{nu}-P_2_)^2^+P_3_, is used for SED fitting. Synchrotron peak frequency (log{nu}_p_), spectral curvature (P_1_), peak flux ({nu}_p_F_{nu}p_), and integrated flux ({nu}F_{nu}_) are successfully obtained for 1392 blazars (461 flat-spectrum radio quasars [FSRQs], 620 BL Lacs [BLs], and 311 blazars of uncertain type [BCUs]; 999 sources have known redshifts). Monochromatic luminosity at radio 1.4GHz, optical R band, X-ray at 1keV and {gamma}-ray at 1GeV, peak luminosity, integrated luminosity, and effective spectral indices of radio to optical ({alpha}_RO_) and optical to X-ray ({alpha}_OX_) are calculated. The "Bayesian classification" is employed to log{nu}_p_ in the rest frame for 999 blazars with available redshift, and the results show that three components are enough to fit the log{nu}_p_ distribution; there is no ultra-high peaked subclass. Based on the three components, the subclasses of blazars using the acronyms of Abdo+ (2010, J/ApJ/716/30) are classified, and some mutual correlations are also studied.
17810. X-ray_peak-BCG offset for PSZ1 clusters
ID:
ivo://CDS.VizieR/J/MNRAS/457/4515
Title:
X-ray_peak-BCG offset for PSZ1 clusters
Short Name:
J/MNRAS/457/4515
Date:
21 Oct 2021
Publisher:
CDS
Description:
We want to characterize the dynamical state of galaxy clusters detected with the Sunyaev-Zeldovich (SZ) effect by Planck and compare them with the dynamical state of clusters selected in X-rays survey. We analysed a representative subsample of the Planck SZ catalogue, containing the 132 clusters with the highest signal to noise ratio and characterize their dynamical state using as an indicator the projected offset between the peak of the X-ray emission and the position of the Brightest cluster galaxy. We compare the distribution of this indicator for the Planck SZ-selected sample and three X-ray-selected samples (HIFLUGCS, MACS and REXCESS). The distributions are significantly different and the fraction of relaxed objects is smaller in the Planck sample (52+/-4 per cent) than in X-ray samples (~=74 per cent) We interpret this result as an indication of different selection effects affecting X-rays (e.g. 'cool core bias') and SZ surveys of galaxy clusters.

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