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3131. Combined General Catalogue of Variable Stars
ID:
ivo://CDS.VizieR/II/250
Title:
Combined General Catalogue of Variable Stars
Short Name:
II/250
Date:
21 Oct 2021
Publisher:
CDS
Description:
The GCVS is the only reference source on all known variable stars. This version contains all of the electronically-readable version as distributed by the Sternberg Astronomical Institute and Institute of Astronomy (Russian Acad.Sci.), Moscow. It includes the catalog of variable stars, updated and completed with the Name-Lists of Variables Stars Nos.67-77 (see IBVS No.2681,1985; No.3058,1987; No.3323,1989; No.3530,1990; No.3840,1993; No.4140,1995; No.4471,1997; No.4659, 1999; No.4870, 2000; No.5135, 2001; No.5422, 2003) a catalog of suspected variables, a cross-index of variable star names, a catalog of extragalactic variables, and a catalog of supernovae.
3132. Combined Lick-Voyager Reference Star Catalogue
ID:
ivo://CDS.VizieR/I/125A
Title:
Combined Lick-Voyager Reference Star Catalogue
Short Name:
I/125A
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalogue contains accurate equatorial coordinates for stars in several bands of sky against which cameras of Voyager spacecraft were pointed for observations in the regions of Jupiter, Saturn, Uranus and Neptune during the flyby. This catalogue is compiled by combining the four reference star catalogues for Voyager mission: Uranus-Voyager Reference Star Catalogue <I/115> Klemola A.R., Owen Jr. W.M. <Lick Obs., Jet Propulsion Lab. (1985)> Neptune-Voyager Reference Star Catalogue <I/140> Klemola A.R., Owen Jr. W.M. <Lick Obs., Jet Propulsion Lab. (1986)> Jupiter-Voyager Reference Star Catalogue <I/152> Klemola A.R., Morabito L., Taraji H. <Lick Obs. (1978)> (Corrections by Owen Jr. W.M., 1990) Saturn-Voyager Reference Star Catalogue <I/153> Klemola A.R., Taraji H., Ocampo A. <Lick Obs. (1979)> (Corrections by Owen Jr. W.M., 1990) Note however that the corrections applied in 1990 to the last two catalogue Jupiter-Voyager and Saturn-Voyager are not incorporated here.
3133. Combined NVSS-FIRST Galaxies (CoNFIG) sample
ID:
ivo://CDS.VizieR/J/MNRAS/390/819
Title:
Combined NVSS-FIRST Galaxies (CoNFIG) sample
Short Name:
J/MNRAS/390/819
Date:
21 Oct 2021
Publisher:
CDS
Description:
The CoNFIG (Combined NVSS-FIRST Galaxies) sample is a new sample of 274 bright radio sources at 1.4GHz. It was defined by selecting all sources with S1.4GHz-1.3Jy from the NRAO Very Large Array (VLA) Sky Survey (NVSS) in the north field of the Faint Images of the Radio Sky at Twenty centimetres (FIRST) survey. New radio observations obtained with the VLA for 31 of the sources are presented. The sample has complete Fanaroff-Riley (FRI)/FRII morphology identification; optical identifications and redshifts are available for 80 and 89 per cent of the sample, respectively, yielding a mean redshift of ~0.71. One of the goals of this survey is to get better definitions of luminosity distributions and source counts of FRI/FRII sources separately, in order to determine the evolution of the luminosity function for each type of source. We present a preliminary analysis, showing that these data are an important step towards examining various evolutionary schemes for these objects and to confirm or correct the dual population unified scheme for radio active galactic nuclei (AGN). Improving our understanding of radio galaxy evolution will give better insight into the role of AGN feedback in galaxy formation.
3134. Combined NVSS-FIRST galaxies (CoNFIG) sample II
ID:
ivo://CDS.VizieR/J/MNRAS/404/1719
Title:
Combined NVSS-FIRST galaxies (CoNFIG) sample II
Short Name:
J/MNRAS/404/1719
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper focuses on a comparison of the space densities of Fanaroff-Riley type I (FR I) and FR II sources at different epochs, with a particular focus on FR I sources. First, we present the concluding steps in constructing the Combined NVSS-FIRST Galaxies (CoNFIG) catalogue, including new Very Large Array observations, optical identifications and redshift estimates. The final catalogue consists of 859 sources over four samples (CoNFIG-1, -2, -3 and -4 with flux density limits of S1.4GHz=1.3, 0.8, 0.2 and 0.05Jy, respectively). It is 95.7 per cent complete in radio morphology classification and 74.3 per cent of the sources have redshift data. Combining CoNFIG with complementary samples, the distribution and evolution of FR I and FR II sources are investigated. We find that FR I sources undergo mild evolution and that, at the same radio luminosity, FR I and FR II sources show similar space density enhancements in various redshift ranges, possibly implying a common evolution.
3135. Combined sample of radio-loud AGNs at 408MHz
ID:
ivo://CDS.VizieR/J/ApJ/744/84
Title:
Combined sample of radio-loud AGNs at 408MHz
Short Name:
J/ApJ/744/84
Date:
21 Oct 2021
Publisher:
CDS
Description:
The work in this paper aims at determining the evolution and possible co-evolution of radio-loud active galactic nuclei (AGNs) and their cores via their radio luminosity functions (i.e., total and core RLFs, respectively). Using a large combined sample of 1063 radio-loud AGNs selected at low radio frequency, we investigate the RLF (radio luminosity function) at 408MHz of steep-spectrum radio sources. Our results support a luminosity-dependent evolution. Using core flux density data of the complete sample 3CRR (Laing et al., 1983, Cat. J/MNRAS/204/151; see also Cat. VIII/1), we investigate the core RLF at 5.0GHz. Based on the combined sample with incomplete core flux data, we also estimate the core RLF using a modified factor of completeness. Both results are consistent and show that the comoving number density of radio cores displays a persistent decline with redshift, implying a negative density evolution. We find that the core RLF is obviously different from the total RLF at the 408 MHz band which is mainly contributed by extended lobes, implying that the cores and extended lobes could not be co-evolving at radio emission.
3136. Combining HCI and RV of nearby stars
ID:
ivo://CDS.VizieR/J/A+A/630/A50
Title:
Combining HCI and RV of nearby stars
Short Name:
J/A+A/630/A50
Date:
21 Oct 2021
Publisher:
CDS
Description:
Nearby stars are prime targets for exoplanet searches and characterization using a variety of detection techniques. Combining constraints from the complementary detection methods of high-contrast imaging (HCI) and radial velocity (RV) can further constrain the planetary architectures of these systems because these methods place limits at different regions of the companion mass and semi-major axis parameter space. Compiling a census of the planet population in the solar neighborhood is important to inform target lists for future space missions that will specifically target nearby stars to search for Earth analogs. We aim to constrain the planetary architectures from the combination of HCI and RV data for six nearby stars within 6pc: tau Ceti, Kapteyn;s star, AX Mic, 40 Eri, HD 36395, and HD 42581. We explored where HCI adds information to constraints from the long-term RV monitoring data for these stars. We compiled the sample from stars with available archival VLT/NACO HCI data at L' band (3.8um), where we expect substellar companions to be brighter for the typically older ages of nearby field stars (>1Gyr). The NACO data were fully reanalyzed using the state-of-the-art direct imaging pipeline PynPoint and combined with RV data from HARPS, Keck/HIRES, and CORALIE. A Monte Carlo approach was used to assess the completeness in the companion mass and semi-major axis parameter space from the combination of the HCI and RV data sets. We find that the HCI data add significant information to the RV constraints, increasing the completeness for certain companions masses and semi-major axes by up to 68-99% for four of the six stars in our sample, and by up to 1-13% for the remaining stars. The improvements are strongest for intermediate semi-major axes (15-40AU), corresponding to the semi-major axes of the ice giants in our own solar system. The HCI mass limits reach 5-20M_Jup_ in the background-limited regime, depending on the age of the star. Through the combination of HCI and RV data, we find that stringent constraints can be placed on the possible substellar companions in these systems. Applying these methods systematically to nearby stars will quantify our current knowledge of the planet population in the solar neighborhood and inform future observations.
3137. COMBS III
ID:
ivo://CDS.VizieR/J/MNRAS/509/122
Title:
COMBS III
Short Name:
J/MNRAS/509/122
Date:
08 Feb 2022 11:31:21
Publisher:
CDS
Description:
The characteristics of the stellar populations in the Galactic bulge inform and constrain the Milky Way's formation and evolution. The metal-poor population is particularly important in light of cosmological simulations, which predict that some of the oldest stars in the Galaxy now reside in its centre. The metal-poor bulge appears to consist of multiple stellar populations that require dynamical analyses to disentangle. In this work, we undertake a detailed chemodynamical study of the metal-poor stars in the inner Galaxy. Using R ~ 20 000 VLT/GIRAFFE spectra of 319 metal-poor (-2.55dex<=[Fe/H]<=0.83dex, with mean [Fe/H]=-0.84dex) stars, we perform stellar parameter analysis and report 12 elemental abundances (C, Na, Mg, Al, Si, Ca, Sc, Ti, Cr, Mn, Zn, Ba, and Ce) with precisions of ~0.10 dex. Based on kinematic and spatial properties, we categorize the stars into four groups, associated with the following Galactic structures: the inner bulge, the outer bulge, the halo, and the disc. We find evidence that the inner and outer bulge population is more chemically complex (i.e. higher chemical dimensionality and less correlated abundances) than the halo population. This result suggests that the older bulge population was enriched by a larger diversity of nucleosynthetic events. We also find one inner bulge star with a [Ca/Mg] ratio consistent with theoretical pair-instability supernova yields and two stars that have chemistry consistent with globular cluster stars.
3138. COMBS survey. Galactic Bulge metal-poor stars
ID:
ivo://CDS.VizieR/J/MNRAS/488/2283
Title:
COMBS survey. Galactic Bulge metal-poor stars
Short Name:
J/MNRAS/488/2283
Date:
21 Oct 2021
Publisher:
CDS
Description:
Chemistry and kinematic studies can determine the origins of stellar population across the Milky Way. The metallicity distribution function of the bulge indicates that it comprises multiple populations, the more metal-poor end of which is particularly poorly understood. It is currently unknown if metal-poor bulge stars ([Fe/H]<-1dex) are part of the stellar halo in the inner most region, or a distinct bulge population or a combination of these. Cosmological simulations also indicate that the metal-poor bulge stars may be the oldest stars in the Galaxy. In this study, we successfully target metal-poor bulge stars selected using SkyMapper photometry. We determine the stellar parameters of 26 stars and their elemental abundances for 22 elements using R~47000 VLT/UVES spectra and contrast their elemental properties with that of other Galactic stellar populations. We find that the elemental abundances we derive for our metal-poor bulge stars have lower overall scatter than typically found in the halo. This indicates that these stars may be a distinct population confined to the bulge. If these stars are, alternatively, part of the inner-most distribution of the halo, this indicates that the halo is more chemically homogeneous at small Galactic radii than at large radii. We also find two stars whose chemistry is consistent with second-generation globular cluster stars. This paper is the first part of the Chemical Origins of Metal-poor Bulge Stars (COMBS) survey that will chemo-dynamically characterize the metal-poor bulge population.
3139. COMBS Survey. Metal-poor bulge stars
ID:
ivo://CDS.VizieR/J/MNRAS/501/5981
Title:
COMBS Survey. Metal-poor bulge stars
Short Name:
J/MNRAS/501/5981
Date:
21 Oct 2021
Publisher:
CDS
Description:
The metal-poor stars in the bulge are important relics of the Milky Way's formation history, as simulations predict that they are some of the oldest stars in the Galaxy. In order to determine if they are truly ancient stars, we must understand their origins. Currently, it is unclear if the metal-poor stars in the bulge ([Fe/H]<-1dex) are merely halo interlopers, a unique accreted population, part of the boxy/peanut-shaped bulge, or a classical bulge population. In this work, we use spectra from the VLT/FLAMES spectrograph to obtain metallicity estimates using the Ca-II triplet of 473 bulge stars (187 of which have [Fe/H]<-1dex), targeted using SkyMapper photometry. We also use Gaia DR2 data to infer the Galactic positions and velocities along with orbital properties for 523 stars. We employ a probabilistic orbit analysis and find that about half of our sample has a >50 per cent probability of being bound to the bulge, and half are halo interlopers. We also see that the occurrence rate of halo interlopers increases steadily with decreasing metallicity across the full range of our sample (-3<[Fe/H]<0.5). Our examination of the kinematics of the confined compared to the unbound stars indicates the metal-poor bulge comprises at least two populations; those confined to the boxy/peanut bulge and halo stars passing through the inner galaxy. We conclude that an orbital analysis approach, as we have employed, is important to understand the composite nature of the metal-poor stars in the inner region.
3140. Cometary HII regions of DR21
ID:
ivo://CDS.VizieR/J/A+A/563/A39
Title:
Cometary HII regions of DR21
Short Name:
J/A+A/563/A39
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep Very Large Array H66{alpha} radio recombination line (RRL) observations of the two cometary HII regions in DR 21. With these sensitive data, we test the "hybrid" bow shock/champagne flow model previously proposed for the DR 21 HII regions.

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