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1261. Iris photometry near southern Cepheids. V. AQ Pup
ID:
ivo://CDS.VizieR/J/AJ/144/187
Title:
Iris photometry near southern Cepheids. V. AQ Pup
Short Name:
J/AJ/144/187
Date:
21 Oct 2021
Publisher:
CDS
Description:
A photometric UBV survey is presented for 610 stars in a region surrounding the Cepheid AQ Puppis and centered southwest of the variable, based upon photoelectric measures for 14 stars and calibrated iris photometry of photographic plates of the field for 596 stars. An analysis of reddening and distance for program stars indicates that the major dust complex in this direction is ~1.8kpc distant, producing differential extinction described by a ratio of total-to-selective extinction of R=A_V_/E_B-V_=3.10+/-0.20. Zero-age main-sequence fitting for the main group of B-type stars along the line of sight yields a distance of 3.21+/-0.19kpc (V_0_-M_V_=12.53+/-0.13s.e.). The 29.97 Cepheid AQ Pup, of field reddening E_B-V_=0.47+/-0.07 (E_B-V_(B0)=0.51+/-0.07), appears to be associated with B-type stars lying within 5' of it as well as with a sparse group of stars, designated Turner 14, centered south of it at J2000.0=07:58:37, -29:25:00, with a mean reddening of E_B-V_=0.81+/-0.01. AQ Pup has an inferred luminosity as a cluster member of <M_V_>=-5.40+/-0.25 and an evolutionary age of 3x10^7^yr. Its observed rate of period increase of +300.1+/-1.2s/yr is an order of magnitude larger than what is observed for Cepheids of comparable period in the third crossing of the instability strip, and may be indicative of a high rate of mass loss or a putative fifth crossing. Another sparse cluster, designated Turner 13, surrounds the newly recognized 2.59 Cepheid V620 Pup, of space reddening E_B-V_=0.64+/-0.02 (E_B-V_(B0)=0.68+/-0.02), distance 2.88+/-0.11kpc (V_0_-M_V_=12.30+/-0.08s.e.), evolutionary age 10^8^yr, and an inferred luminosity as a likely cluster member of <M_V_>=-2.74+/-0.11. V620 Pup is tentatively identified as a first crosser, pending additional observations.
1262. IR measurement of quasar obscuration
ID:
ivo://CDS.VizieR/J/ApJ/679/140
Title:
IR measurement of quasar obscuration
Short Name:
J/ApJ/679/140
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent work has suggested that the fraction of obscured AGNs declines with increasing luminosity, but it has been difficult to quantify this trend. Here we attempt to measure this fraction as a function of luminosity by studying the ratio of mid-infrared to intrinsic nuclear bolometric luminosity in unobscured AGNs. Because the mid-infrared is created by dust reprocessing of shorter wavelength nuclear light, this ratio is a diagnostic of f_obsc_, the fraction of solid angle around the nucleus covered by obscuring matter. In order to eliminate possible redshift dependences while also achieving a large dynamic range in luminosity, we have collected archival 24um MIPS photometry from objects with z~1 in the Sloan Digital Sky Survey DR5, the Great Observatories Origins Deep Survey, and the Cosmic Evolution Survey. To measure the bolometric luminosity for each object, we used archival optical data supplemented by GALEX data.
1263. IR observations of galaxies in the Coma cluster
ID:
ivo://CDS.VizieR/J/AJ/142/148
Title:
IR observations of galaxies in the Coma cluster
Short Name:
J/AJ/142/148
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a thorough study of the specific star formation rates (sSFRs) for MIPS 24um selected galaxies in the Coma cluster. We build galaxy spectral energy distributions using optical (u', g', r', i', z'), near-infrared (J, H, Ks), and mid- to far-infrared (Infrared Array Camera and MIPS) photometry. New and archival spectra confirm 210 cluster members. Subsequently, the total infrared luminosity, galaxy stellar mass, and sSFR for the members are determined by measuring best-fit templates. Using an array of complementary diagnostics, we search for any contaminating active galactic nuclei, but find few. We compare obscured SFRs to unobscured rates derived from extinction-corrected H{alpha} emission line measurements. The agreement between these two values leads us to conclude that there is no evidence for an additionally obscured component. In our spectroscopic sample, complete to 80% for r'<19.5, we find that all starbursts are blue and are dwarfs, having masses <10^9^M_{sun}_. Examining the location of these starbursts within the cluster, we confirm that there is a lower fraction in the cluster core.
1264. Iron element abundances in 3 very metal-poor stars
ID:
ivo://CDS.VizieR/J/ApJ/890/119
Title:
Iron element abundances in 3 very metal-poor stars
Short Name:
J/ApJ/890/119
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained new detailed abundances of the Fe-group elements Sc through Zn (Z=21-30) in three very metal-poor ([Fe/H]~-3) stars: BD+03 740, BD-13 3442, and CD-33 1173. High-resolution ultraviolet Hubble Space Telescope/Space Telescope Imaging Spectrograph spectra in the wavelength range 2300-3050{AA} were gathered, and complemented by an assortment of optical echelle spectra. The analysis featured recent laboratory atomic data for a number of neutral and ionized species for all Fe-group elements except Cu and Zn. A detailed examination of scandium, titanium, and vanadium abundances in large-sample spectroscopic surveys indicates that they are positively correlated in stars with [Fe/H]<=-2. The abundances of these elements in BD+03 740, BD-13 3442, CD-33 1173, and HD 84937 (studied in a previous paper of this series) are in accord with these trends and lie at the high end of the correlations. Six elements have detectable neutral and ionized features, and generally their abundances are in reasonable agreement. For Cr we find only minimal abundance disagreement between the neutral (mean of [CrI/Fe]=+0.01) and ionized species (mean of [CrII/Fe]=+0.08), unlike most studies in the past. The prominent exception is Co, for which the neutral species indicates a significant overabundance (mean of [CoI/H]=-2.53), while no such enhancement is seen for the ionized species (mean of [CoII/H]=-2.93). These new stellar abundances, especially the correlations among Sc, Ti, and V, suggest that models of element production in early high-mass metal-poor stars should be revisited.
1265. IR photometry of field RR Lyrae variable stars
ID:
ivo://CDS.VizieR/J/AJ/158/105
Title:
IR photometry of field RR Lyrae variable stars
Short Name:
J/AJ/158/105
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present multi-epoch infrared photometry in the K_s_-band for 74 bright RR Lyrae variable stars tied directly to the Two-Micron All-Sky Survey (2MASS) photometric system. We systematize additional K-band photometry from the literature to the 2MASS system and combine it to obtain photometry for 146 RR Lyrae stars on a consistent, modern system. A set of outlier stars in the literature photometry is identified and discussed. Reddening estimates for each star are gathered from the literature and combined to provide an estimate of the interstellar absorption affecting each star, and we find excellent agreement with another source in the literature. We utilize trigonometric parallaxes from the Second Data Release of the European Space Agency's Gaia astrometric satellite to determine the absolute magnitude, M_Ks_ for each of these stars, and analyze them using the astrometry-based luminosity prescription to obtain a parallax-based calibration of M_K_ (RR). Our period-luminosity-metallicity relationship is M_Ks_=(-2.8+/-0.2)(logP+0.27)+(0.12+/-0.02) ([Fe/H]+1.3)-(0.41+/-0.03) mag. A Gaia global zero-point error of {pi}_zp_=-0.042+/-0.013 mas is determined for this sample of RR Lyrae stars.
1266. IR photometry of massive LMC stars
ID:
ivo://CDS.VizieR/J/AJ/138/1003
Title:
IR photometry of massive LMC stars
Short Name:
J/AJ/138/1003
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 1750 massive stars in the Large Magellanic Cloud (LMC), with accurate spectral types compiled from the literature, and a photometric catalog for a subset of 1268 of these stars, with the goal of exploring their infrared properties. The photometric catalog consists of stars with infrared counterparts in the Spitzer SAGE survey database, for which we present uniform photometry from 0.3 to 24um in the UBVIJHKs+IRAC+MIPS24 bands. The resulting infrared color-magnitude diagrams illustrate that the supergiant B[e], red supergiant, and luminous blue variable (LBV) stars are among the brightest infrared point sources in the LMC, due to their intrinsic brightness, and at longer wavelengths, due to dust. We detect infrared excesses due to free-free emission among ~900 OB stars, which correlate with luminosity class. We confirm the presence of dust around 10 supergiant B[e] stars, finding the shape of their spectral energy distributions (SEDs) to be very similar, in contrast to the variety of SED shapes among the spectrally variable LBVs. The similar luminosities of B[e] supergiants (log L/L_{sun}_>=4) and the rare, dusty progenitors of the new class of optical transients (e.g., SN 2008S and NGC 300 OT), plus the fact that dust is present in both types of objects, suggests a common origin for them. We find the infrared colors for Wolf-Rayet stars to be independent of spectral type and their SEDs to be flatter than what models predict.
1267. IR photometry of massive stars in the SMC
ID:
ivo://CDS.VizieR/J/AJ/140/416
Title:
IR photometry of massive stars in the SMC
Short Name:
J/AJ/140/416
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 5324 massive stars in the Small Magellanic Cloud (SMC), with accurate spectral types compiled from the literature, and a photometric catalog for a subset of 3654 of these stars, with the goal of exploring their infrared properties. The photometric catalog consists of stars with infrared counterparts in the Spitzer SAGE-SMC survey database, for which we present uniform photometry from 0.3 to 24um in the UBVIJHKs+IRAC+MIPS24 bands.
1268. IR source catalog of AKARI NEP-Wide field
ID:
ivo://CDS.VizieR/J/A+A/548/A29
Title:
IR source catalog of AKARI NEP-Wide field
Short Name:
J/A+A/548/A29
Date:
21 Oct 2021
Publisher:
CDS
Description:
The InfraRed Camera (IRC) onboard AKARI has a comprehensive wavelength coverage with 9 photometric bands at 2-24 micron. Based on the NEP-Wide survey of AKARI (which covered a 5.4 sq.deg circular area centered on the NEP), we constructed a catalog for the infrared sources found in the survey area. Here we present the catalog containing about 114,800 sources detected at the nine IRC filter bands. This is a band-merged catalogue including all of the photometry results from the supplementary optical data as well as the IRC bands. To validate a source at a given IRC band, we searched counterparts in the other bands. The band-merging was done based on this cross-matching of the sources among the filter bands. If there is no detection in a certain band, we assigned the 99.000. The NIR sources having no counterpart in any other bands are finally excluded to avoid the false objects. See the reference for the details of the NEP-Wide survey and data reduction.
1269. ISLAndS project. III. Variable stars
ID:
ivo://CDS.VizieR/J/ApJ/850/137
Title:
ISLAndS project. III. Variable stars
Short Name:
J/ApJ/850/137
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a census of variable stars in six M31 dwarf spheroidal satellites observed with the Hubble Space Telescope. We detect 870 RR Lyrae (RRL) stars in the fields of And I (296), II (251), III (111), XV (117), XVI (8), and XXVIII (87). We also detect a total of 15 Anomalous Cepheids, three eclipsing binaries, and seven field RRL stars compatible with being members of the M31 halo or the Giant Stellar Stream. We derive robust and homogeneous distances to the six galaxies using different methods based on the properties of the RRL stars. Working with the up-to-date set of Period-Wesenheit (I, B-I) relations published by Marconi et al., we obtain distance moduli of {mu}0=[24.49, 24.16, 24.36, 24.42, 23.70, 24.43]mag (respectively), with systematic uncertainties of 0.08mag and statistical uncertainties <0.11mag. We have considered an enlarged sample of 16 M31 satellites with published variability studies, and compared their pulsational observables (e.g., periods and amplitudes) with those of 15 Milky Way satellites for which similar data are available. The properties of the (strictly old) RRL in both satellite systems do not show any significant difference. In particular, we found a strikingly similar correlation between the mean period distribution of the fundamental RRL pulsators (RRab) and the mean metallicities of the galaxies. This indicates that the old RRL progenitors were similar at the early stage in the two environments, suggesting very similar characteristics for the earliest stages of evolution of both satellite systems.
1270. Isolated compact elliptical galaxies
ID:
ivo://CDS.VizieR/J/other/Sci/348.418
Title:
Isolated compact elliptical galaxies
Short Name:
J/other/Sci/348.
Date:
21 Oct 2021
Publisher:
CDS
Description:
Compact elliptical galaxies form a rare class of stellar system (~30 presently known) characterized by high stellar densities and small sizes and often harboring metal-rich stars. They were thought to form through tidal stripping of massive progenitors, until two isolated objects were discovered where massive galaxies performing the stripping could not be identified. By mining astronomical survey data, we have now found 195 compact elliptical galaxies in all types of environment. They all share similar dynamical and stellar population properties. Dynamical analysis for nonisolated galaxies demonstrates the feasibility of their ejection from host clusters and groups by three-body encounters, which is in agreement with numerical simulations. Hence, isolated compact elliptical and isolated quiescent dwarf galaxies are tidally stripped systems that ran away from their hosts.