- ID:
- ivo://CDS.VizieR/J/AJ/150/123
- Title:
- Catalog of 316 K giant candidates
- Short Name:
- J/AJ/150/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Infrared (IR) excesses around K-type red giants (RGs) have previously been discovered using Infrared Astronomy Satellite (IRAS) data, and past studies have suggested a link between RGs with overabundant Li and IR excesses, implying the ejection of circumstellar shells or disks. We revisit the question of IR excesses around RGs using higher spatial resolution IR data, primarily from the Wide-field Infrared Survey Explorer. Our goal was to elucidate the link between three unusual RG properties: fast rotation, enriched Li, and IR excess. Our sample of RGs includes those with previous IR detections, a sample with well-defined rotation and Li abundance measurements with no previous IR measurements, and a large sample of RGs asserted to be Li-rich in the literature; we have 316 targets thought to be K giants, about 40% of which we take to be Li-rich. In 24 cases with previous detections of IR excess at low spatial resolution, we believe that source confusion is playing a role, in that either (a) the source that is bright in the optical is not responsible for the IR flux, or (b) there is more than one source responsible for the IR flux as measured in IRAS. We looked for IR excesses in the remaining sources, identifying 28 that have significant IR excesses by ~20{mu}m (with possible excesses for 2 additional sources). There appears to be an intriguing correlation in that the largest IR excesses are all in Li-rich K giants, though very few Li-rich K giants have IR excesses (large or small). These largest IR excesses also tend to be found in the fastest rotators. There is no correlation of IR excess with the carbon isotopic ratio, ^12^C/^13^C. IR excesses by 20{mu}m, though relatively rare, are at least twice as common among our sample of Li-rich K giants. If dust shell production is a common by-product of Li enrichment mechanisms, these observations suggest that the IR excess stage is very short-lived, which is supported by theoretical calculations. Conversely, the Li-enrichment mechanism may only occasionally produce dust, and an additional parameter (e.g., rotation) may control whether or not a shell is ejected.
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2882. Catalog of LMC HI clouds
- ID:
- ivo://CDS.VizieR/J/ApJS/171/419
- Title:
- Catalog of LMC HI clouds
- Short Name:
- J/ApJS/171/419
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 21cm neutral hydrogen interferometric survey of the Large Magellanic Cloud (LMC) combined with the Parkes multibeam HI single-dish survey (2003MNRAS.339...87S) clearly shows that the HI gas is distributed in the form of clumps or clouds. The HI clouds and clumps have been identified using a thresholding method with three separate brightness temperature thresholds (T_b_). Each catalog of HI cloud candidates shows a power-law relationship between the sizes and the velocity dispersions of the clouds roughly following the Larson law scaling {sigma}_v_{prop.to}R^0.5^, with steeper indices associated with dynamically hot regions. The clouds in each catalog have roughly constant virial parameters as a function of mass, suggesting that the clouds are all in roughly the same dynamical state, but the values of the virial parameter are significantly larger than unity, showing that turbulent motions dominate gravity in these clouds. The mass distribution of the clouds is a power law with differential indices between -1.6 and -2.0 for the three catalogs. In contrast, the distribution of mean surface densities is a lognormal distribution.
- ID:
- ivo://CDS.VizieR/J/MNRAS/473/30
- Title:
- Catalog of Ly{alpha} emitters
- Short Name:
- J/MNRAS/473/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a measurement of the fraction of Lyman {alpha} (Ly{alpha}) emitters (X_Ly{alpha}_) amongst HST continuum-selected galaxies at 3<z<6 with the Multi-Unit Spectroscopic Explorer (MUSE) on the VLT. Making use of the first 24 MUSE-Wide pointings in GOODS-South, each having an integration time of 1h, we detect 100Ly{alpha} emitters and find X_Ly{alpha}_>~0.5 for most of the redshift range covered, with 29 per cent of the Ly{alpha} sample exhibiting rest equivalent widths (rest-EWs)<=15{AA}. Adopting a range of rest-EW cuts (0~75{AA}), we find no evidence of a dependence of XLy{alpha} on either redshift or ultraviolet luminosity.
- ID:
- ivo://CDS.VizieR/II/134
- Title:
- Catalog of Magnetic Field Measurements
- Short Name:
- II/134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains references to all measurements of stellar magnetic fields published in the literature between 1958 and 1981. The catalog provides for each object identifications, position, magnitude, period, extrema of the magnetic field measured, number of measurements, method used, spectral type, bibliographic references, and notes.
- ID:
- ivo://CDS.VizieR/J/other/A+AT/23.213
- Title:
- Catalog of massive close binaries
- Short Name:
- J/other/A+AT/23.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains compilations of observable data for 176 massive close binaries with components earlier than approximately B5 of the main sequence are presented.
- ID:
- ivo://CDS.VizieR/J/AJ/150/42
- Title:
- Catalog of 2612 M dwarfs from LAMOST
- Short Name:
- J/AJ/150/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We develop a template-fit method to automatically identify and classify late-type K and M dwarfs in spectra from the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST). A search of the commissioning data, acquired in 2009-2010, yields the identification of 2612 late-K and M dwarfs. The template fit method also provides spectral classification to half a subtype, classifies the stars along the dwarf-subdwarf (dM/sdM/esdM/usdM) metallicity sequence, and provides improved metallicity/gravity information on a finer scale. The automated search and classification is performed using a set of cool star templates assembled from the Sloan Digital Sky Survey spectroscopic database. We show that the stars can be efficiently classified despite shortcomings in the LAMOST commissioning data which include bright sky lines in the red. In particular we find that the absolute and relative strengths of the critical TiO and CaH molecular bands around 7000{AA} are cleanly measured, which provides accurate spectral typing from late-K to mid-M, and makes it possible to estimate metallicity classes in a way that is more efficient and reliable than with the use of spectral indices or spectral-index based parameters such as {zeta}_TiO/CaH_. Most of the cool dwarfs observed by LAMOST are found to be metal-rich dwarfs (dM). However, we identify 52 metal-poor M subdwarfs (sdM), 5 very metal-poor extreme subdwarfs (esdM) and 1 probable ultra metal-poor subdwarf (usdM). We use a calibration of spectral type to absolute magnitude and estimate spectroscopic distances for all the stars; we also recover proper motions from the SUPERBLINK and PPMXL catalogs. Our analysis of the estimated transverse motions suggests a mean velocity and standard deviation for the UVW components of velocity to be: <U>=-9.8km/s, {sigma}_U_=35.6km/s; <V> =-22.8km/s, {sigma}_V_=30.6km/s; <W> =-7.9km/s, {sigma}_W_=28.4km/s. The resulting values are in general agreement with previous reported results, which yields confidence in our spectral classification and spectroscopic distance estimates, and illustrates the potential for using LAMOST spectra of K and M dwarfs for investigating the chemo-kinematics of the local Galactic disk and halo.
- ID:
- ivo://CDS.VizieR/J/AJ/147/106
- Title:
- Catalog of member galaxies in A2319
- Short Name:
- J/AJ/147/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Asymmetric X-ray emission and a powerful cluster-scale radio halo indicate that A2319 is a merging cluster of galaxies. This paper presents our multicolor photometry for A2319 with 15 optical intermediate filters in the Beijing-Arizona-Taiwan-Connecticut (BATC) system. There are 142 galaxies with known spectroscopic redshifts within the viewing field of 58'x58' centered on this rich cluster, including 128 member galaxies (called sample I). A large velocity dispersion in the rest frame, 1622_-70_^+91^km/s, suggests merger dynamics in A2319. The contour map of projected density and localized velocity structure confirm the so-called A2319B substructure, at ~10' northwest to the main concentration A2319A. The spectral energy distributions (SEDs) of more than 30000 sources are obtained in our BATC photometry down to V~20mag. A u-band (~3551{AA}) image with better seeing and spatial resolution, obtained with the Bok 2.3m telescope at Kitt Peak, is taken to make star-galaxy separation and distinguish the overlapping contamination in the BATC aperture photometry. With color-color diagrams and photometric redshift technique, 233 galaxies brighter than h_BATC_=19.0 are newly selected as member candidates after an exclusion of false candidates with contaminated BATC SEDs by eyeball-checking the u-band Bok image. The early-type galaxies are found to follow a tight color-magnitude correlation. Based on sample I and the enlarged sample of member galaxies (called sample II), subcluster A2319B is confirmed. The star formation properties of cluster galaxies are derived with the evolutionary synthesis model, PEGASE, assuming a Salpeter initial mass function and an exponentially decreasing star formation rate (SFR). A strong environmental effect on star formation histories is found in the manner that galaxies in the sparse regions have various star formation histories, while galaxies in the dense regions are found to have shorter SFR time scales, older stellar ages, and higher interstellar medium metallicities. For the merging cluster A2319, local surface density is a better environmental indicator rather than the cluster-centric distance. Compared with the well-relaxed cluster A2589, a higher fraction of star-forming galaxies is found in A2319, indicating that the galaxy-scale turbulence stimulated by the subcluster merger might have played a role in triggering the star formation activity.
- ID:
- ivo://CDS.VizieR/J/ApJS/181/233
- Title:
- Catalog of merging galaxies
- Short Name:
- J/ApJS/181/233
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalog and images of interacting and merging galaxies obtained with morphological identification from Canada-France-Hawaii Telescope observations. We first used a morphological pattern recognition searching routine to select possible candidates, and then visually inspected the images of these candidates to identify true merging/interacting sources. We discover 15147 new pairs of merging galaxies within 422deg^2^ of Red Sequence Cluster Survey 2. Furthermore, we also find nine new candidates of galaxy clusters by searching for regions with significant density enhancements of merging galaxies. This catalog has the largest number of morphologically identified interacting and merging galaxies based on consistent searching criteria. These sources provide a uniform sample of merging galaxies for further photometric and spectroscopic studies of galaxy evolution.
- 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.
- ID:
- ivo://CDS.VizieR/VII/96
- Title:
- Catalog of morphological properties of Abell clusters
- Short Name:
- VII/96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalog is presented which contains Rood-Sastry (1971, hereafter RS) morphological types for all 2712 Abell clusters.
