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451. Catalog of SDSS compact groups of galaxies
ID:
ivo://CDS.VizieR/J/AJ/127/1811
Title:
Catalog of SDSS compact groups of galaxies
Short Name:
J/AJ/127/1811
Date:
21 Oct 2021
Publisher:
CDS
Description:
Compact groups (CGs) of galaxies - relatively poor groups of galaxies in which the typical separations between members is of the order of a galaxy diameter - offer an exceptional laboratory for the study of dense galactic environments with short (<1Gyr) dynamical timescales. We present an objectively defined catalog of CGs in 153deg^2^ of the Sloan Digital Sky Survey (SDSS) Early Data Release (<J/AJ/123/567>). To identify CGs, we applied a modified version of Hickson's criteria of 1982 aimed at finding the highest-density CGs and thus reducing the number of chance alignments. Our catalog contains 175 CGs down to a limiting galaxy magnitude of r*=21. The resulting catalog has a median depth of z_med_~0.13, substantially deeper than previous CG catalogs. Since the SDSS will eventually image up to one-quarter of the celestial sphere, we expect our final catalog, based on the completed SDSS, will contain on the order of 5000-10000CGs. This catalog will be useful for conducting studies of the general characteristics of CGs, their environments, and their component galaxies.
452. Catalog of stars in Sgr dwarf galaxy
ID:
ivo://CDS.VizieR/J/AJ/145/163
Title:
Catalog of stars in Sgr dwarf galaxy
Short Name:
J/AJ/145/163
Date:
21 Oct 2021
Publisher:
CDS
Description:
We measure the spatial density of F turnoff stars in the Sagittarius dwarf tidal stream, from Sloan Digital Sky Survey data, using statistical photometric parallax. We find a set of continuous, consistent parameters that describe the leading Sgr stream's position, direction, and width for 15 stripes in the north Galactic cap, and three stripes in the south Galactic cap. We produce a catalog of stars that has the density characteristics of the dominant leading Sgr tidal stream that can be compared with simulations. We find that the width of the leading (north) tidal tail is consistent with recent triaxial and axisymmetric halo model simulations. The density along the stream is roughly consistent with common disruption models in the north, but possibly not in the south. We explore the possibility that one or more of the dominant Sgr streams has been misidentified, and that one or more of the "bifurcated" pieces is the real Sgr tidal tail, but we do not reach definite conclusions. If two dwarf progenitors are assumed, fits to the planes of the dominant and "bifurcated" tidal tails favor an association of the Sgr dwarf spheroidal galaxy with the dominant southern stream and the "bifurcated" stream in the north. In the north Galactic cap, the best fit Hernquist density profile for the smooth component of the stellar halo is oblate, with a flattening parameter q=0.53, and a scale length of r_0_=6.73. The southern data for both the tidal debris and the smooth component of the stellar halo do not match the model fits to the north, although the stellar halo is still overwhelmingly oblate. Finally, we verify that we can reproduce the parameter fits on the asynchronous MilkyWay@home volunteer computing platform.
453. Catalog of Suspected Nearby Young Stars
ID:
ivo://CDS.VizieR/J/AJ/153/95
Title:
Catalog of Suspected Nearby Young Stars
Short Name:
J/AJ/153/95
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new nearby young moving group (NYMG) kinematic membership analysis code, LocAting Constituent mEmbers In Nearby Groups (LACEwING), a new Catalog of Suspected Nearby Young Stars, a new list of bona fide members of moving groups, and a kinematic traceback code. LACEwING is a convergence-style algorithm with carefully vetted membership statistics based on a large numerical simulation of the Solar Neighborhood. Given spatial and kinematic information on stars, LACEwING calculates membership probabilities in 13 NYMGs and three open clusters within 100 pc. In addition to describing the inputs, methods, and products of the code, we provide comparisons of LACEwING to other popular kinematic moving group membership identification codes. As a proof of concept, we use LACEwING to reconsider the membership of 930 stellar systems in the Solar Neighborhood (within 100 pc) that have reported measurable lithium equivalent widths. We quantify the evidence in support of a population of young stars not attached to any NYMGs, which is a possible sign of new as-yet-undiscovered groups or of a field population of young stars.
454. Catalog of ultrawide binary stars from Gaia DR2
ID:
ivo://CDS.VizieR/J/ApJS/246/4
Title:
Catalog of ultrawide binary stars from Gaia DR2
Short Name:
J/ApJS/246/4
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an extensive and pure sample of ultrawide binary stars with separations of 0.01<~s/pc<~1 in the solar neighborhood. Using data from Gaia DR2, we define kinematic subpopulations via the systems' tangential velocities, i.e., disk-like (v_{perp},tot_<=40km/s), intermediate (v_{perp},tot_=40-85km/s), and halo-like (v_{perp},tot_>=85km/s) binaries, presuming that these velocity cuts represent a rough ordering in the binaries' age and metallicity. Through stringent cuts on astrometric precision, we can obtain pure binary samples at such wide separations with thousands of binaries in each sample. Fitting a smoothly broken power law for the separation distribution, we find that its slope at s=10^2.5-4^au is the same for all subpopulations, p(s){propto}s^{gamma}^ with {gamma}~-1.54. However, the logarithmic slope of p(s) steepens at s>~10^4^au. We find some evidences that the degree of steepening increases with the binaries' age, with a slope change of only {Delta}{gamma}~0.5 for disk-like stars, but {Delta}{gamma}>~1 for halo-like stars. This trend is contrary to what might be expected if steepening at wide separations were due to gravitational perturbations by molecular clouds or stars, which would preferentially disrupt disk binaries. If we were to interpret steepening at s>~10^4^au as a consequence of disruption by MAssive Compact Halo Objects (MACHOs), we would have to invoke a MACHO population inconsistent with other constraints. As a more plausible alternative, we propose a simple model to predict the separation distribution of wide binaries formed in dissolving star clusters. This model generically predicts {gamma}~-1.5 as observed, with steepening at larger separations due to the finite size of binaries' birth clusters.
455. 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.
456. 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.
457. 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).
458. Catalogue and Bibliography of UV Cet stars
ID:
ivo://CDS.VizieR/J/A+AS/139/555
Title:
Catalogue and Bibliography of UV Cet stars
Short Name:
J/A+AS/139/555
Date:
21 Oct 2021
Publisher:
CDS
Description:
This new catalogue of flare stars includes 463 objects. It contains astrometric, spectral and photometric data as well as information on the infrared, radio and X-ray properties and general stellar parameters. From the total reference list of about 3400 articles, partial lists selected by objects, authors, key words and by any pairs of these criteria can be obtained.
459. Catalogue of close binaries
ID:
ivo://CDS.VizieR/J/MNRAS/370/2013
Title:
Catalogue of close binaries
Short Name:
J/MNRAS/370/2013
Date:
21 Oct 2021
Publisher:
CDS
Description:
A catalogue of close eclipsing binary systems (detached and semidetached) with at least one of the components located in the delta Scuti region of the Cepheid instability strip is presented. The positions of the stars in the instability strip are determined by their accurate temperatures and luminosities. Observationally detected binaries (20 semidetached, four detached and one unclassified) with oscillating components were included in the catalogue as a separate table. The primaries of the oscillating Algols tend to be located near the blue edge of the instability strip. Using reliable luminosities and temperatures determined by recent photometric and spectroscopic studies, we have found that at least one or two components of 71 detached and 90 semidetached systems are located in the delta Scuti region of the Cepheid instability strip. In addition, 36 detached or semidetached systems discovered by the Hipparcos satellite were also given as a separate list. One of their components is seen in the delta Scuti region, according to their spectral type or BV colours. They are potential candidate binaries with the delta Scuti-type pulsating components which need further photometric and spectroscopic studies in better precision. This catalogue covers information and literature references for 25 known and 197 candidate binaries with pulsating components.
460. Catalogue of Galactic high-mass X-ray binaries
ID:
ivo://CDS.VizieR/J/A+A/455/1165
Title:
Catalogue of Galactic high-mass X-ray binaries
Short Name:
J/A+A/455/1165
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new edition of the catalogue of high-mass X-ray binaries in the Galaxy. The catalogue contains source name(s), coordinates, finding chart, X-ray luminosity, system parameters, and stellar parameters of the components and other characteristic properties of 114 high-mass X-ray binaries, together with a comprehensive selection of the relevant literature. The aim of this catalogue is to provide the reader with some basic information on the X-ray sources and their counterparts in other wavelength ranges (gamma-rays, UV, optical, IR, radio). About 60% of the high-mass X-ray binary candidates are known or suspected Be/X-ray binaries, while 32% are supergiant/X-ray binaries. Some sources, however, are only tentatively identified as high-mass X-ray binaries on the basis of their X-ray properties similar to the known high-mass X-ray binaries. Further identification in other wavelength bands is needed to finally determine the nature of these sources. In cases where there is some doubt about the high-mass nature of the X-ray binary this is mentioned. Literature published before 1 October 2005 has, as far as possible, been taken into account.