- ID:
- ivo://CDS.VizieR/J/AJ/120/2338
- Title:
- Abell 576 redshifts
- Short Name:
- J/AJ/120/2338
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe observations of the nearby (cz=11487km/s) cluster of galaxies Abell 576 beyond the virial radius and into the infall region where galaxies are on their first or second pass through the cluster. Using 1057 redshifts, we use the infall pattern in redshift space to determine the mass profile of A576 to a radius of ~4h^-1^Mpc.
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- ID:
- ivo://CDS.VizieR/J/A+AS/94/399
- Title:
- Absolute fluxes and distances of PN
- Short Name:
- J/A+AS/94/399
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a complete list of averaged recalibrated absolute H{beta} fluxes, global (where possible) relative He II {lambda} 4686 fluxes, 5-GHz radio flux densities, and H{alpha}/H{beta} interstellar extinction constants for 778 Galactic planetary nebulae. The catalog provides much of the fundamental data required to generate Zanstra temperatures. When data with the lowest errors are selected, the optical and radio/optical extinctions show a peculiar correlation, with the radio values slightly high at low extinction and notably low at high extinction. The data are used, along with the best estimates of angular diameters, to calculate Shklovsky distances according to the Daub scheme on the scale used earlier by Cahn and Kaler (1971ApJS...22..319C). Use of this distance scale shows approximate equality of the death rates of optically thick and optically thin planetary nebulae. The method gives the correct distances to the Magellanic Clouds.
- ID:
- ivo://CDS.VizieR/J/ApJ/721/1608
- Title:
- Absolute UV magnitudes of type Ia SNe
- Short Name:
- J/ApJ/721/1608
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine the absolute magnitudes and light-curve shapes of 14 nearby (redshift z=0.004-0.027) Type Ia supernovae (SNe Ia) observed in the ultraviolet (UV) with the Swift Ultraviolet/Optical Telescope. Colors and absolute magnitudes are calculated using both a standard Milky Way extinction law and one for the Large Magellanic Cloud that has been modified by circumstellar scattering. We find very different behavior in the near-UV filters (uvw1_rc_ covering ~2600-3300{AA} after removing optical light, and u~3000-4000{AA}) compared to a mid-UV filter (uvm2~2000-2400{AA}).
- ID:
- ivo://CDS.VizieR/J/AJ/144/95
- Title:
- Abundance in stars of the outer galactic disk. IV.
- Short Name:
- J/AJ/144/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radial velocities and chemical abundances for nine stars in the old, distant open clusters Be18, Be21, Be22, Be32, and PWM4. For Be18 and PWM4, these are the first chemical abundance measurements. Combining our data with literature results produces a compilation of some 68 chemical abundance measurements in 49 unique clusters. For this combined sample, we study the chemical abundances of open clusters as a function of distance, age, and metallicity. We confirm that the metallicity gradient in the outer disk is flatter than the gradient in the vicinity of the solar neighborhood. We also confirm that the open clusters in the outer disk are metal-poor with enhancements in the ratios [{alpha}/Fe] and perhaps [Eu/Fe]. All elements show negligible or small trends between [X/Fe] and distance (<0.02dex/kpc), but for some elements, there is a hint that the local (R_GC_<13kpc) and distant (R_GC_>13kpc) samples may have different trends with distance. There is no evidence for significant abundance trends versus age (<0.04dex/Gyr). We measure the linear relation between [X/Fe] and metallicity, [Fe/H], and find that the scatter about the mean trend is comparable to the measurement uncertainties. Comparison with solar neighborhood field giants shows that the open clusters share similar abundance ratios [X/Fe] at a given metallicity. While the flattening of the metallicity gradient and enhanced [{alpha}/Fe] ratios in the outer disk suggest a chemical enrichment history different from that of the solar neighborhood, we echo the sentiments expressed by Friel et al. that definitive conclusions await homogeneous analyses of larger samples of stars in larger numbers of clusters. Arguably, our understanding of the evolution of the outer disk from open clusters is currently limited by systematic abundance differences between various studies.
- ID:
- ivo://CDS.VizieR/J/ApJS/245/10
- Title:
- A catalog of galaxies in direction of Perseus
- Short Name:
- J/ApJS/245/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 5437 morphologically classified sources in the direction of the Perseus galaxy cluster core, among them 496 early-type low-mass galaxy candidates. The catalog is primarily based on V-band imaging data acquired with the William Herschel Telescope, which we used to conduct automated source detection and derive photometry. We additionally reduced archival Subaru multiband imaging data in order to measure aperture colors and perform a morphological classification, benefiting from 0.5" seeing conditions in the r-band data. Based on morphological and color properties, we extracted a sample of early-type low-mass galaxy candidates with absolute V-band magnitudes in the range of -10 to -20mag. In the color-magnitude diagram, the galaxies are located where the red sequence for early-type cluster galaxies is expected, and they lie on the literature relation between absolute magnitude and Sersic index. We classified the early-type dwarf candidates into nucleated and nonnucleated galaxies. For the faint candidates, we found a trend of increasing nucleation fraction toward brighter luminosity or higher surface brightness, similar to what is observed in other nearby galaxy clusters. We morphologically classified the remaining sources as likely background elliptical galaxies, late-type galaxies, edge-on disk galaxies, and likely merging systems and discussed the expected contamination fraction through non-early-type cluster galaxies in the magnitude-size surface brightness parameter space. Our catalog reaches its 50% completeness limit at an absolute V-band luminosity of -12mag and a V-band surface brightness of 26mag/arcsec^2^. This makes it the largest and deepest catalog with coherent coverage compared to previous imaging studies of the Perseus cluster.
- ID:
- ivo://CDS.VizieR/J/AJ/160/271
- Title:
- A catalog of ~30000 galaxies with ALFALFA-SDSS
- Short Name:
- J/AJ/160/271
- Date:
- 08 Dec 2021
- Publisher:
- CDS
- Description:
- We present a HI optical catalog of ~30000 galaxies based on the 100% complete Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey combined with data from the Sloan Digital Sky Survey (SDSS). Our goal is to facilitate the public use of the completed ALFALFA catalog by providing carefully determined matches to SDSS counterparts, including matches for ~10000 galaxies that do not have SDSS spectra. These identifications can provide a basis for further crossmatching with other surveys using SDSS photometric IDs as a reference point. We derive absolute magnitudes and stellar masses for each galaxy using optical colors combined with an internal reddening correction designed for small- and intermediate-mass galaxies with active star formation. We also provide measures of stellar masses and star formation rates based on infrared and/or ultraviolet photometry for galaxies that are detected by the Wide-field Infrared Survey Explorer and/or the Galaxy Evolution Explorer. Finally, we compare the galaxy population in the ALFALFA-SDSS sample with the populations in several other publicly available galaxy catalogs and confirm that ALFALFA galaxies typically have lower masses and bluer colors.
- ID:
- ivo://CDS.VizieR/J/ApJS/199/8
- Title:
- A compilation of interstellar column densities
- Short Name:
- J/ApJS/199/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have collated absorption line data toward 3008 stars in order to create a unified database of interstellar column densities. These data have been taken from a number of different published sources and include many different species and ionizations. The preliminary results from our analysis show a tight relation [N(H)/E(B-V)=6.12x10^21^] between N(H) and E(B-V). Similar plots have been obtained with many different species, and their correlations along with the correlation coefficients are presented.
- ID:
- ivo://CDS.VizieR/J/A+A/623/A108
- Title:
- Age of 269 GDR2 open clusters
- Short Name:
- J/A+A/623/A108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Gaia Second Data Release provides precise astrometry and photometry for more than 1.3 billion sources. This catalog opens a new era concerning the characterization of open clusters and test stellar models, paving the way for better understanding of the disk properties. The aim of the paper is to improve the knowledge of cluster parameters, using only the unprecedented quality of the Gaia photometry and astrometry. We have made use of the membership determination based on the precise Gaia astrometry and photometry. We applied an automated Bayesian tool, BASE-9, to fit stellar isochrones on the observed G, GBP, GRP magnitudes of the high probability member stars. We derive parameters such as age, distance modulus, and extinction for a sample of 269 open clusters, selecting only low reddening objects and discarding very young clusters, for which techniques other than isochrone-fitting are more suitable for estimating ages.
- ID:
- ivo://CDS.VizieR/J/A+A/585/A38
- Title:
- All-sky extinction maps
- Short Name:
- J/A+A/585/A38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extinction remains one of the most reliable methods of measuring column density of nearby Galactic interstellar clouds. The current and ongoing near-infrared surveys enable the mapping of extinction over large sky areas. We produce allsky extinction maps using the 2MASS near-infrared survey. We use the NICER and NICEST methods to convert the near-infrared colour excesses to extinction estimates. The results are presented in Healpix format at the resolutions of 3.0, 4.5, and 12.0-arcmin.
- ID:
- ivo://CDS.VizieR/J/A+A/585/A78
- Title:
- All-sky near-infrared extinction map
- Short Name:
- J/A+A/585/A78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared (NIR) extinction remains one of the most reliable methods of measuring the column density of dense interstellar clouds. Extinction can be estimated using the reddening of the light of background stars. Several methods exist (e.g., NICE, NICER, NICEST, GNICER) to combine observations of several NIR bands into extinction maps. We present a new method of estimating extinction based on NIR multiband observations and examine its performance. Our basic method uses a discretised version of the distribution of intrinsic stellar colours directly. The extinction of individual stars and the average over a resolution element are estimated with Markov chain Monte Carlo (MCMC) methods. Several variations of the basic method are tested, and the results are compared to NICER calculations.
