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2231. Catalog of 24um sources toward Galactic Center
ID:
ivo://CDS.VizieR/J/ApJS/181/227
Title:
Catalog of 24um sources toward Galactic Center
Short Name:
J/ApJS/181/227
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a ~1.5x8{deg}^2^ (220x1195pc^2^) multiband imaging photometer for Spitzer 24um image of the Galactic center (GC) and an accompanying point-source list. This image is the highest spatial resolution (6"~0.25pc) and sensitivity map ever taken across the GC at this wavelength, showing the emission by warm dust in unprecedented detail. Over 120000 point sources are identified in this catalog with signal-to-noise ratios greater than five and flux densities from 0.6mJy to 9Jy.
2232. Catalog of variability selected AGNs in GOODS
ID:
ivo://CDS.VizieR/J/ApJ/723/737
Title:
Catalog of variability selected AGNs in GOODS
Short Name:
J/ApJ/723/737
Date:
21 Oct 2021
Publisher:
CDS
Description:
Variability is a property shared by practically all active galactic nuclei (AGNs). This makes variability selection a possible technique for identifying AGNs. Given that variability selection makes no prior assumption about spectral properties, it is a powerful technique for detecting both low-luminosity AGNs in which the host galaxy emission is dominating and AGNs with unusual spectral properties. In this paper, we will discuss and test different statistical methods for the detection of variability in sparsely sampled data that allow full control over the false positive rates. We will apply these methods to the GOODS North and South fields and present a catalog of variable sources in the z band in both GOODS fields. Out of the 11 931 objects checked, we find 155 variable sources at a significance level of 99.9%, corresponding to about 1.3% of all objects. After rejection of stars and supernovae, 139 variability-selected AGNs remain. Their magnitudes reach down as faint as 25.5mag in z. Spectroscopic redshifts are available for 22 of the variability-selected AGNs, ranging from 0.046 to 3.7. The absolute magnitudes in the rest-frame z band range from ~-18 to -24, reaching substantially fainter than the typical luminosities probed by traditional X-ray and spectroscopic AGN selection in these fields. Therefore, this is a powerful technique for future exploration of the evolution of the faint end of the AGN luminosity function up to high redshifts.
2233. Catalog of white dwarfs in SDSS-DR1
ID:
ivo://CDS.VizieR/J/ApJ/607/426
Title:
Catalog of white dwarfs in SDSS-DR1
Short Name:
J/ApJ/607/426
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the full spectroscopic white dwarf and hot subdwarf sample from the Sloan Digital Sky Survey (SDSS) First Data Release, DR1. We find 2551 white dwarf stars of various types, 240 hot subdwarf stars, and an additional 144 objects we have identified as uncertain white dwarf stars. Of the white dwarf stars, 1888 are nonmagnetic DA types and 171 are nonmagnetic DBs. The remaining (492) objects consist of all different types of white dwarf stars: DO, DQ, DC, DH, DZ, hybrid stars such as DAB, etc., and those with nondegenerate companions. We fit the DA and DB spectra with a grid of models to determine the T_eff_ and logg for each object. For all objects, we provide coordinates, proper motions, SDSS photometric magnitudes, and enough information to retrieve the spectrum/image from the SDSS public database. This catalog nearly doubles the known sample of spectroscopically identified white dwarf stars. In the DR1 imaged area of the sky, we increase the known sample of white dwarf stars by a factor of 8.5. We also comment on several particularly interesting objects in this sample.
2234. Catalog of wide companions to Hipparcos stars
ID:
ivo://CDS.VizieR/J/AJ/144/102
Title:
Catalog of wide companions to Hipparcos stars
Short Name:
J/AJ/144/102
Date:
21 Oct 2021
Publisher:
CDS
Description:
A catalog of common-proper-motion (CPM) companions to stars within 67pc of the Sun is constructed based on the SUPERBLINK proper-motion survey. It contains 1392 CPM pairs with angular separations 30"<{rho}<1800", relative proper motion between the two components less than 25mas/yr, and magnitudes and colors of the secondaries consistent with those of dwarfs in the (M_V_, V-J) diagram. In addition, we list 21 candidate white dwarf CPM companions with separations under 300", about half of which should be physical. We estimate a 0.31 fraction of pairs with red dwarf companions to be physical systems (about 425 objects), while the rest (mostly wide pairs) are chance alignments. For each candidate companion, the probability of a physical association is evaluated. The distribution of projected separations s of the physical pairs between 2kAU and 64kAU follows f(s){prop.to}s^-1.5^, which decreases faster than Opik's law. We find that solar-mass dwarfs have no less than 4.4%+/-0.3% companions with separations larger than 2kAU, or 3.8%+/-0.3% per decade of orbital separation in the 2-16kAU range. The distribution of mass ratio of those wide companions is approximately uniform in the 0.1<q<1.0 range, although we observe a dip at q=~0.5 which, if confirmed, could be evidence of bimodal distribution of companion masses. New physical CPM companions to two exoplanet host stars are discovered.
2235. Catalog of XMM X-ray galaxy groups
ID:
ivo://CDS.VizieR/J/A+A/566/A140
Title:
Catalog of XMM X-ray galaxy groups
Short Name:
J/A+A/566/A140
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 129 X-ray galaxy groups, covering a redshift range 0.04<z<1.23, selected in the ~3deg^2^ part of the CFHTLS W1 field overlapping XMM observations performed under the XMM-LSS project. We carry out a statistical study of the redshift evolution out to redshift one of the magnitude gap between the first and the second brightest cluster galaxies of a well defined mass-selected group sample. We find that the slope of the relation between the fraction of groups and the magnitude gap steepens with redshift, indicating a larger fraction of fossil groups at lower redshifts. We find that 22.2+/-6% of our groups at z<=0.6 are fossil groups. We compare our results with the predictions of three semi-analytic models based on the Millennium simulation. The intercept of the relation between the magnitude of the brightest galaxy and the value of magnitude gap becomes brighter with increasing redshift. This trend is steeper than the model predictions which we attribute to the younger stellar age of the observed brightest cluster galaxies. This trend argues in favor of stronger evolution of the feedback from active galactic nuclei at z<1 compared to the models. The slope of the relation between the magnitude of the brightest cluster galaxy and the value of the gap does not evolve with redshift and is well reproduced by the models, indicating that the tidal galaxy stripping, put forward as an explanation of the occurrence of the magnitude gap, is both a dominant mechanism and sufficiently well modeled.
2236. Catalog of X-ray selected BL Lac objects
ID:
ivo://CDS.VizieR/J/AJ/145/31
Title:
Catalog of X-ray selected BL Lac objects
Short Name:
J/AJ/145/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents a catalog of 312 X-ray selected BL Lacertae objects (XBLs), optically identified through the end of 2011. It contains the names from different surveys, equatorial coordinates, redshifts, multifrequency flux values, and luminosities for each source. In addition, the different characteristics of XBLs are statistically investigated (redshift, radio/optical/X-ray luminosities, central black hole (BH) mass, synchrotron peak frequency, broadband spectral indices, optical flux variability). Their values are collected through an extensive bibliographic and database search or calculated by us. The redshifts range from 0.031 to 0.702 with a maximum of the distribution at z=0.223. The 1.4GHz luminosities of XBLs log{nu}L_{nu}_~39-42erg/s while optical V and X-ray 0.1-2.4keV bands show log{nu}L_{nu}_~43-46erg/s. The XBL hosts are elliptical galaxies with effective radii r_eff_=3.26-25.40kpc and ellipticities, {epsilon}=0.04-0.52. Their R-band absolute magnitudes M_R_ range from -21.11mag to -24.86mag with a mean value of -22.83mag. The V-R indices of the hosts span from 0.61 to 1.52 and reveal a fourth-degree polynomial relationship with z that enables us to evaluate the redshifts of five sources whose V-R indices were determined from the observations but whose redshifts values are either not found or not confirmed. The XBL nuclei show a wider range of 7.31mag for M_R_ with the highest luminosity corresponding to M_R_=-27.24mag. The masses of central BHs are found in the interval logM_BH_=7.39-9.30 solar masses (with distribution maximum at logM_BH_/M_{sun}_=8.30). The synchrotron peak frequencies are spread over the range log{nu}_peak_=14.56-19.18Hz with a peak of the distribution at log{nu}_peak_=16.60Hz. The broadband radio-to-optical ({alpha}_ro_), optical-to-X-ray ({alpha}_ox_), and radio-to-X-ray ({alpha}_rx_) spectral indices are distributed in the intervals (0.17,0.59), (0.56,1.48), and (0.41,0.75), respectively. In the optical energy range, the overall flux variability increases, on average, towards shorter wavelengths: <{Delta}m>=1.22,1.50, and 1.82mag through the R, V, B bands of Johnson-Cousins system, respectively. XBLs seem be optically less variable at the intranight timescales compared to the radio-selected BL Lacs (RBLs).
2237. Catalog of X-ray sources from TTM/COMIS
ID:
ivo://CDS.VizieR/J/PAZh/26/355
Title:
Catalog of X-ray sources from TTM/COMIS
Short Name:
J/PAZh/26/355
Date:
21 Oct 2021
Publisher:
CDS
Description:
A Catalog of X-ray sources as observed by the TTM/COMIS telescope onboard the Mir-Kvant observatory is presented. Brief information about the 67 sources detected at a confidence level higher than 4{sigma} between 1988 and 1998 is provided. X-ray properties and charateristic spectra of different types of sources are briefly described.
2238. Catalog of X-ray sources in NGC 3379
ID:
ivo://CDS.VizieR/J/ApJS/179/142
Title:
Catalog of X-ray sources in NGC 3379
Short Name:
J/ApJS/179/142
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the properties of the discrete X-ray sources detected in our monitoring program of the 'typical' elliptical galaxy, NGC 3379, observed with Chandra ACIS-S in five separate pointings, resulting in a co-added exposure of 324ks. From this deep observation, 132 sources have been detected within the region overlapped by all observations, 98 of which lie within the D_25_ ellipse of the galaxy. These 132 sources range in L_X_ from 6x10^35^erg/s (with 3{sigma} upper limit <=4x10^36^erg/s) to ~2x10^39^erg/s, including one source with L_X_>1x10^39^erg/s, which has been classified as an ULX. From optical data, 10 X-ray sources have been determined to be coincident with a globular cluster, these sources tend to have high X-ray luminosity, with three of these sources exhibiting L_X_>1x10^38^erg/s. From X-ray source photometry, it has been determined that the majority of the 132 sources that have well constrained colors, have values that are consistent with typical LMXB spectra. In addition to this, a subpopulation of 10 sources has been found to exhibit very hard spectra and it is expected that most of these sources are absorbed background AGN. There are 64 sources in this population that exhibit long-term variability, indicating that they are accreting compact objects. Five of these sources have been identified as transient candidates, with a further 3 possible transients. Spectral variations have also been identified in the majority of the source population, where a diverse range of variability has been identified, indicating that there are many different source classes located within this galaxy.
2239. Catalog of X-ray sources in NGC 4278
ID:
ivo://CDS.VizieR/J/ApJS/181/605
Title:
Catalog of X-ray sources in NGC 4278
Short Name:
J/ApJS/181/605
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the properties of the discrete X-ray sources detected in our monitoring program of the globular cluster (GC) rich elliptical galaxy, NGC 4278, observed with Chandra ACIS-S in six separate pointings, resulting in a co-added exposure of 458ks. From this deep observation, 236 sources have been detected within the region overlapped by all observations, 180 of which lie within the D25 ellipse of the galaxy. These 236 sources range in L_X_ from 3.5x10^36^erg/s (with 3{sigma} upper limit <=1x10^37^erg/s) to ~2x10^40^erg/s, including the central nuclear source which has been classified as a LINER. From optical data, 39 X-ray sources have been determined to be coincident with a GC, these sources tend to have high X-ray luminosity, with 10 of these sources exhibiting L_X_>1x10^38^erg/s. From X-ray source photometry, it has been determined that the majority of the 236 point sources that have well-constrained colors have values that are consistent with typical low-mass X-ray binary spectra, with 29 of these sources expected to be background objects from the log N-log S relation. There are 103 sources in this population that exhibit long-term variability, indicating that they are accreting compact objects. Three of these sources have been identified as transient candidates, with a further three possible transients. Spectral variations have also been identified in the majority of the source population, where a diverse range of variability has been identified, indicating that there are many different source classes located within this galaxy.
2240. Catalog of X-ray sources in the CYDER fields
ID:
ivo://CDS.VizieR/J/ApJ/621/104
Title:
Catalog of X-ray sources in the CYDER fields
Short Name:
J/ApJ/621/104
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results from the Calan-Yale Deep Extragalactic Research (CYDER) survey. The main goal of this survey is to study serendipitous X-ray sources detected by Chandra in an intermediate flux range (10^-15^ to 10^-12^ergs/s) that comprises most of the X-ray background. A total of 267 X-ray sources spread over five archived fields were detected.

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