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651. Catalog of M, L, & T dwarfs from PS1 3{pi} Survey
ID:
ivo://CDS.VizieR/J/ApJS/234/1
Title:
Catalog of M, L, & T dwarfs from PS1 3{pi} Survey
Short Name:
J/ApJS/234/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 9888 M, L and T dwarfs detected in the Pan-STARRS1 3{pi} Survey (PS1), covering three-quarters of the sky. Our catalog contains nearly all known objects of spectral types L0-T2 in the PS1 field, with objects as early as M0 and as late as T9, and includes PS1, 2MASS, AllWISE, and Gaia DR1 photometry. We analyze the different types of photometry reported by PS1 and use two types in our catalog in order to maximize both depth and accuracy. Using parallaxes from the literature, we construct empirical SEDs for field ultracool dwarfs spanning 0.5-12{mu}m. We determine typical colors of M0-T9 dwarfs and highlight the distinctive colors of subdwarfs and young objects. We combine astrometry from PS1, 2MASS, and Gaia DR1 to calculate new proper motions for our catalog. We achieve a median precision of 2.9mas/yr, a factor of ~3-10 improvement over previous large catalogs. Our catalog contains proper motions for 2405 M6-T9 dwarfs and includes the largest set of homogeneous proper motions for L and T dwarfs published to date, 406 objects for which there were no previous measurements, and 1176 objects for which we improve upon previous literature values. We analyze the kinematics of ultracool dwarfs in our catalog and find evidence that bluer but otherwise generic late-M and L field dwarfs (i.e., not subdwarfs) tend to have tangential velocities higher than those of typical field objects. With the public release of the PS1 data, this survey will continue to be an essential tool for characterizing the ultracool dwarf population.
652. Catalog of M31 SNR candidates
ID:
ivo://CDS.VizieR/J/ApJ/786/130
Title:
Catalog of M31 SNR candidates
Short Name:
J/ApJ/786/130
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a survey of optically emitting supernova remnants (SNRs) in M31 based on H{alpha} and [S II] images in the Local Group Survey. Using these images, we select objects that have [S II]:H{alpha}>0.4 and circular shapes. We identify 156 SNR candidates, of which 76 are newly found objects. We classify these SNR candidates according to two criteria: the SNR progenitor type (Type Ia and core-collapse (CC) SNRs) and the morphological type. Type Ia and CC SNR candidates make up 23% and 77%, respectively, of the total sample. Most of the CC SNR candidates are concentrated in the spiral arms, while the Type Ia SNR candidates are rather distributed over the entire galaxy, including the inner region. The CC SNR candidates are brighter in H{alpha} and [S II] than the Type Ia SNR candidates. We derive a cumulative size distribution of the SNR candidates, finding that the distribution of the candidates with 17<D<50 pc is fitted well by a power law with the power-law index {alpha}=2.53+/-0.04. This indicates that most of the SNR candidates identified in this study appear to be in the Sedov-Taylor phase. The [S II]:H{alpha} distribution of the SNR candidates is bimodal, with peaks at [S II]:H{alpha}~0.4 and~0.9. The properties of these SNR candidates vary little with the galactocentric distance. The H{alpha} and [S II] surface brightnesses show a good correlation with the X-ray luminosity of the SNR candidates that are center-bright.
653. Catalog of Optically selected cores
ID:
ivo://CDS.VizieR/J/ApJS/123/233
Title:
Catalog of Optically selected cores
Short Name:
J/ApJS/123/233
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalog of 406 dense cores optically selected by using the STScI Digitized Sky Survey (DSS). In this catalog 306 cores have neither an embedded young stellar object (EYSO) nor a pre-main-sequence (PMS) star, 94 cores have EYSOs (one core has both an EYSO and a PMS star), and six cores have PMS stars only. Our sample of dense cores in the catalog is fairly complete within a category of northern Lynds class 5 and 6 clouds and southern Hartley et al. class A clouds, providing a database useful for the systematic study of dense cores. Most of the cores listed in the catalog have diameters between 0.05 and 0.36 pc with a mean of ~0.24pc. The sizes (~0.33pc in the mean) of cores with EYSOs are found to be usually larger than the sizes (~0.22pc in the mean) of starless cores. The typical mean gas density of the cores is ~7x10^3^cm^-3^. Most of the cores are more likely elongated than spherical (mean aspect ratio: ~2.4). The ratio of the number of cores with EYSOs to the number of starless cores for our sample is about 0.3, suggesting that the typical lifetime of starless cores is 0.3-1.6Myr, about 3 times longer than the duration of the class 0 and class I phases. This lifetime is shorter than expected from models of ambipolar diffusion, by factors of 2-44.
654. 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.
655. 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.
656. 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.
657. Catalog of UBVRI Photometry of Globular Clusters
ID:
ivo://CDS.VizieR/II/117
Title:
Catalog of UBVRI Photometry of Globular Clusters
Short Name:
II/117
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometric data directly obtained in UBVRI or converted to UBVRI magnitudes are tabulated. The data comprise approximately 4600 records from 56 individuals and contains data unpublished at the time of the compilation as well as published data.
658. 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.
659. 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.
660. 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.