- 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.
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- ID:
- ivo://CDS.VizieR/J/A+A/560/A76
- Title:
- Catalog of stellar clusters in the inner Galaxy
- Short Name:
- J/A+A/560/A76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Stars are born within dense clumps of giant molecular clouds, and constitute young stellar agglomerates known as embedded clusters, which only evolve into bound open clusters under special conditions. We statistically study all embedded clusters (ECs) and open clusters (OCs) known so far in the inner Galaxy, in particular investigating their interaction with the surrounding molecular environment and the differences in their evolution.
- ID:
- ivo://CDS.VizieR/III/244
- Title:
- Catalog of Stellar Rotational Velocities
- Short Name:
- III/244
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is a compilation of the observed projected rotational velocities, V_rot_*sin(i), for 28179 stars from 166 open clusters, globular clusters and associations. The catalog.dat file contains 39351 individual V_rot_*sin(i) data, together with the error and the method of determination. Because of the possible confusion with the use of different names for stars belonging to clusters we have included alternative names using SIMBAD nomenclature. Rotational velocities from CDS catalogue III/226 (Glebocki+ 2000) are included. Information about the number of stars in each cluster as well as other cluster names can be found in the "clusters.dat" file. The bibliographical references are provided in the "refs.dat" file. The file "mean.dat" contains mean V*sin(i) values for each star. The individual v*sin(i) measurements were reduced to a uniform standard (to remove the systematic errors) and a weighted average of V*sin(i) was calculated. The V*sin(i) values used as standards are presented in the "standards.dat" file.
- ID:
- ivo://CDS.VizieR/J/ApJ/848/34
- Title:
- CATalog of Stellar Unified Properties
- Short Name:
- J/ApJ/848/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Almost every star in our Galaxy is likely to harbor a terrestrial planet, but accurate measurements of an exoplanet's mass and radius demand accurate knowledge of the properties of its host star. The imminent TESS and CHEOPS missions are slated to discover thousands of new exoplanets. Along with WFIRST, which will directly image nearby planets, these surveys make urgent the need to better characterize stars in the nearby solar neighborhood (<30pc). We have compiled the CATalog of Stellar Unified Properties (CATSUP) for 951 stars, including such data as: Gaia astrometry; multiplicity within stellar systems; stellar elemental abundance measurements; standardized spectral types; CaII H and K stellar activity indices; GALEX NUV and FUV photometry; and X-ray fluxes and luminosities from ROSAT, XMM, and Chandra. We use this data-rich catalog to find correlations, especially between stellar emission indices, colors, and galactic velocity. Additionally, we demonstrate that thick-disk stars in the sample are generally older, have lower activity, and have higher velocities normal to the galactic plane. We anticipate that CATSUP will be useful for discerning other trends among stars within the nearby solar neighborhood, for comparing thin-disk versus thick-disk stars, for comparing stars with and without planets, and for finding correlations between chemical and kinematic properties.
- 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.
- 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/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.