- ID:
- ivo://CDS.VizieR/J/A+A/546/A67
- Title:
- Catalog of strong MgII absorbers
- Short Name:
- J/A+A/546/A67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A significantly higher incidence of strong (rest equivalent width Wr>1{AA}) intervening MgII absorption is observed along gamma-ray burst (GRB) sight-lines relative to those of quasar sight-lines. A geometrical explanation for this discrepancy has been suggested: the ratio of the beam size of the source to the characteristic size of an MgII absorption system can influence the observed MgII equivalent width, if these two sizes are comparable. We investigate whether the differing beam sizes of the continuum source and broad-line region of Sloan Digital Sky Survey (SDSS) quasars produce a discrepancy between the incidence of strong MgII absorbers illuminated by the quasar continuum region and those of absorbers illuminated by both continuum and broad-line region light.
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- ID:
- ivo://CDS.VizieR/J/A+A/639/A28
- Title:
- Catalog of super star clusters in IRAS 17138-1017
- Short Name:
- J/A+A/639/A28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Currently, the global characteristics and evolution of super star clusters (SSCs) are not well understood, due to the large distances to their host galaxies. We aim to study the population of SSCs in IRAS 17138-1017, a luminous infrared galaxy (LIRG), in terms of age, extinction, mass, and luminosity distribution. We analyzed imaging data in the near-infrared from the GeMS/GSAOI instrument on the Gemini telescope and generated simulations with the radiative transfer code MontAGN. The extraction of SSCs from the images and their photometry in J, H, and Ks allowed us to derive color-color and color-magnitude diagrams. Comparison with a theoretical stellar evolutionary track gives a first hint into the extinction towards each SSC, as well as their ages, despite some degeneracy between those two quantities. Spectra given by our radiative transfer code MontAGN, which includes dust emission, also provide insightful predictions and comparisons. We detect with a fair degree of confidence 54 SSCs of m_Ks between 16 mag and 21 mag with a median instrumental uncertainty of 0.05 mag. When plotted on a color-color diagram and a color-magnitude diagram, it appears that most of the sources are very much extinct with respect to an intrinsic theoretical evolutionary track. Once de-reddened, the colors point unambiguously to two distinct and very recent starburst episodes at 2.8 and 4.5Myr. While the SSCs in the 4.5Myr starburst are distributed along the spiral arms, the 2.8Myr SSCs are concentrated in the central region. The luminosity and mass functions present a classical power-law behavior, although with shallower slopes than generally observed in LIRGs. Comparison with radiative transfer simulations shows that, especially for the youngest SSCs, the thermal emission by dust is not negligible and could explain the few very red SSCs that could not be de-reddened safely. This effect could lead to a misevaluation of the age of the starburst by at most 1 or 2Myr.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJS/219/1
- Title:
- Catalog of Type-1 AGNs from SDSS-DR7
- Short Name:
- J/ApJS/219/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have recently identified a substantial number of type 1 active galactic nuclei (AGNs) featuring weak broad-line regions (BLRs) at z<0.2 from detailed analysis of galaxy spectra in the Sloan Digital Sky Survey Data Release 7. These objects predominantly show a stellar continuum but also a broad H{alpha} emission line, indicating the presence of a low-luminosity AGN oriented so that we are viewing the central engine directly without significant obscuration. These accreting black holes have previously eluded detection due to their weak nature. The newly discovered BLR AGNs have increased the number of known type 1 AGNs by 49%. Some of these new BLR AGNs were detected with the Chandra X-ray Observatory, and their X-ray properties confirm that they are indeed type 1 AGNs. Based on our new and more complete catalog of type 1 AGNs, we derived the type 1 fraction of AGNs as a function of [OIII]{lambda}5007 emission luminosity and explored the possible dilution effect on obscured AGNs due to star formation. The new type 1 AGN fraction shows much more complex behavior with respect to black hole mass and bolometric luminosity than has been suggested previously by the existing receding torus model. The type 1 AGN fraction is sensitive to both of these factors, and there seems to be a sweet spot (ridge) in the diagram of black hole mass and bolometric luminosity. Furthermore, we present the possibility that the Eddington ratio plays a role in determining opening angles.
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/429/1125
- Title:
- Catalog of Ultraluminous X-ray sources
- Short Name:
- J/A+A/429/1125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of ultraluminous X-ray sources (ULXs) in external galaxies. The aim of this catalogue is to provide easy access to the properties of ULXs, their possible counterparts at other wavelengths (optical, IR, and radio), and their host galaxies. The catalogue contains 229 ULXs reported in the literature until April 2004. Most ULXs are stellar-mass-black hole X-ray binaries, but it is not excluded that some ULXs could be intermediate-mass black holes. A small fraction of the candidate ULXs may be background Active Galactic Nuclei (AGN) and Supernova Remnants (SNRs). ULXs with luminosity above 10^40^erg/s are found in both starburst galaxies and in the halos of early-type galaxies.
- 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.
- 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.
- 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.
- 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.
