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17261. VVV Survey outer bulge RRab stars
ID:
ivo://CDS.VizieR/J/A+A/591/A145
Title:
VVV Survey outer bulge RRab stars
Short Name:
J/A+A/591/A145
Date:
21 Oct 2021
Publisher:
CDS
Description:
The VISTA Variables in the Via Lactea (VVV) is a near-IR time-domain survey of the Galactic bulge and southern plane. One of the main goals of this survey is to reveal the 3D structure of the Milky Way through their variable stars. In particular, enormous numbers of RR Lyrae stars have been discovered in the inner regions of the bulge (-8{deg}<~b<~-1{deg}) by optical surveys such as OGLE and MACHO, but leaving an unexplored window of more than ~47 sq deg (-10.0{deg}<~l<~+10.7{deg} and -10.3{deg}<~b<~-8.0{deg}) observed by the VVV Survey. Our goal is to characterize the RR Lyrae stars in the outer bulge in terms of their periods, amplitudes, Fourier coefficients, and distances in order to evaluate the 3D structure of the bulge in this area. The distance distribution of RR Lyrae stars will be compared to that of red clump stars, which is known to trace a X-shaped structure, in order to determine whether these two different stellar populations share the same Galactic distribution. A search for RR Lyrae stars was performed in more than ~47 sq deg at low Galactic latitudes (-10.3{deg}<~b<~-8.0{deg}). In the procedure the {chi}^2^ value and analysis of variance (AoV) statistic methods were used to determine the variability and periodic features of the light curves, respectively. To prevent misclassifications, the analysis was performed only on the fundamental mode RR Lyrae stars (RRab) owing to similarities found in the near-IR light curve shapes of contact eclipsing binaries (W UMa) and first overtone RR Lyrae stars (RRc). On the other hand, the red clump stars of the same analyzed tiles were selected, and cuts in the color-magnitude diagram were applied and the maximum distance restricted to ~20kpc in order to construct a similar catalog in terms of distances and covered area compared to the RR Lyrae stars. We report the detection of more than 1000 RR Lyrae ab-type stars in the VVV Survey located in the outskirts of the Galactic bulge. A few of them are possibly associated with the Sagittarius Dwarf Spheroidal Galaxy. We calculated colours, reddening, extinction, and distances of the detected RR Lyrae stars in order to determine the outer bulge 3D structure. Our main result is that, at the low galactic latitudes mapped here, the RR Lyrae stars trace a centrally concentrated spheroidal distribution. This is a noticeably different spatial distribution to the one traced by red clump stars known to follow a bar and X-shaped structure. We estimate the completeness of our sample at 80% for K_s_<=15mag.
17262. VVV Survey RR Lyr stars in Southern Galactic plane
ID:
ivo://CDS.VizieR/J/AJ/153/179
Title:
VVV Survey RR Lyr stars in Southern Galactic plane
Short Name:
J/AJ/153/179
Date:
21 Oct 2021
Publisher:
CDS
Description:
Deep near-IR images from the VISTA Variables in the Via Lactea (VVV) Survey were used to search for RR Lyrae stars in the Southern Galactic plane. A sizable sample of 404 RR Lyrae of type ab stars was identified across a thin slice of the fourth Galactic quadrant (295{deg}<l<350{deg}, -2.24{deg}<b<-1.05{deg}). The sample's distance distribution exhibits a maximum density that occurs at the bulge tangent point, which implies that this primarily Oosterhoff type I population of RRab stars does not trace the bar delineated by their red clump counterparts. The bulge RR Lyrae population does not extend beyond l~340{deg}, and the sample's spatial distribution presents evidence of density enhancements and substructure that warrants further investigation. Indeed, the sample may be employed to evaluate Galactic evolution models, and is particularly lucrative since half of the discovered RR Lyrae are within reach of Gaia astrometric observations.
17263. VY CMa ALMA NaCl images
ID:
ivo://CDS.VizieR/J/A+A/592/A76
Title:
VY CMa ALMA NaCl images
Short Name:
J/A+A/592/A76
Date:
21 Oct 2021
Publisher:
CDS
Description:
At the end of their lives, most stars lose a significant amount of mass through a stellar wind. The specific physical and chemical circumstances that lead to the onset of the stellar wind for cool luminous stars are not yet understood. Complex geometrical morphologies in the circumstellar envelopes prove that various dynamical and chemical processes are interlocked and that their relative contributions are not easy to disentangle. We aim to study the inner-wind structure (R<250R*) of the well-known red supergiant VY CMa, the archetype for the class of luminous red supergiant stars experiencing high mass loss. Specifically, the objective is to unravel the density structure in the inner envelope and to examine the chemical interaction between gas and dust species. We analyse high spatial resolution (~0.24"x0.13") ALMA Science Verification (SV) data in band 7, in which four thermal emission lines of gaseous sodium chloride (NaCl) are present at high signal-to-noise ratio.
17264. Vyssotsky's Catalogues 1950.0
ID:
ivo://CDS.VizieR/III/13
Title:
Vyssotsky's Catalogues 1950.0
Short Name:
III/13
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog includes the results of a complete survey of the McCormick objective prism plates for M dwarf stars. catalog.dat includes identifications, magnitudes, proper motions in RA and Dec, spectral types and parallaxes.
17265. Wackerling Catalog of Early-Type Emission-Line Stars
ID:
ivo://nasa.heasarc/wackerling
Title:
Wackerling Catalog of Early-Type Emission-Line Stars
Short Name:
Wackerling
Date:
01 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The Wackerling Catalog contains entries for 5326 early-type emission-line stars. Of these stars, 1424 have no spectral classification but are assumed to be of early type. Some 71 percent of the stars in this catalog can also be found in the Mount Wilson and the Mount Wilson-Michigan survey catalogs. The Wackerling Catalog contains numerous cross identifications to other designations (common name, HD, DM, LS, MWC, TON, HIL, WRA, HEN, etc.), rough spectroscopic types, magnitudes (visual and blue), and positions. The version of the Wackerling Catalog on which the HEASARC database is based was obtained from the ADC and differs in some respects from the original published version, notice. This online catalog was originally ingested by the HEASARC in July 1999, based on a machine-readable table obtained from the ADC/CDS data centers. It was updated in May 2020 to reflect updates to the spect_type_code values made by the CDS for improved database compatibility. This is a service provided by NASA HEASARC .
17266. Walraven photometry in Sco-Cen association
ID:
ivo://CDS.VizieR/J/A+A/216/44
Title:
Walraven photometry in Sco-Cen association
Short Name:
J/A+A/216/44
Date:
21 Oct 2021
Publisher:
CDS
Description:
Walraven photometry is presented of established and probable members of the Scorpio-Centaurus OB association. For each star, effective temperature and surface gravity are derived using Kurucz atmosphere models (1979ApJS...40....1K). From the Straizys and Kuriliene (1981Ap&SS..80..353S) tables, absolute magnitudes are calculated. Distance moduli and visual extinctions are determined for all stars. From a comparison of the HR-diagrams of the stars in each subgroup with theoretical isochrones, the ages of the three subgroups are derived. The distances to the three subgroups are shown to be different; there is a general trend (also within each subgroup) for the distances to be larger at higher galactic longitudes. The visual extinction in the youngest subgroup Upper-Scorpius, is well correlated with the IRAS 100-micron map. The distance toward the Ophiuchus dark clouds is found to be 125 pc, based on the photometric distances to the stars. Most of the early-type stars in Upper-Scorpius are located at the far side of the dark clouds.
17267. Walraven photometry near AG Car
ID:
ivo://CDS.VizieR/J/A+AS/98/505
Title:
Walraven photometry near AG Car
Short Name:
J/A+AS/98/505
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Walraven-photometric data of 114 stars of 5.9<V<14.7 within 17 arcmin of the Luminous Blue Variable AG Car (HD 94910). The results are expressed in terms of V-magnitude in the Johnson system and in observed and extinction-free colours in the Walraven system. For a description of the Walraven photometric system, see e.g. <GCPD/11>
17268. W Aql APEX spectrum
ID:
ivo://CDS.VizieR/J/A+A/642/A20
Title:
W Aql APEX spectrum
Short Name:
J/A+A/642/A20
Date:
23 Mar 2022 16:31:40
Publisher:
CDS
Description:
W Aql is an asymptotic giant branch (AGB) star with an atmospheric elemental abundance ratio C/O~=0.98. It has previously been reported to have circumstellar molecular abundances intermediate between those of M-type and C-type AGB stars, which respectively have C/O<1 and C/O>1. This intermediate status is considered typical for S-type stars, although our understanding of the chemical content of their circumstellar envelopes is currently rather limited. We wish to assess the reported intermediate status of W Aql by analysing the line emission of molecules that have not been observed towards this star before. We have performed observations in the frequency range 159-268GHz with the SEPIA/B5 and PI230 instruments on the APEX telescope. We make abundance estimates through direct comparison to available spectra towards a number of well-studied AGB stars and based on rotational diagram analysis in the case of one molecule. From a compilation of our abundance estimates and those found in the literature for two M-type (R Dor, IK Tau), two S-type ({chi} Cyg, W Aql), and two C-type stars (V Aql, IRC +10 216), we conclude that W Aql's circumstellar environment appears considerably closer to that of a C-type AGB star than to that of an M-type AGB star. In particular, we detect emission from C_2_H, SiC_2_, SiN, and HC_3_N, molecules previously only detected towards the circumstellar environment of C-type stars. This conclusion, based on the chemistry of the gaseous component of the circumstellar environment, is further supported by reports in the literature on the presence of atmospheric molecular bands and spectral features of dust species which are typical for C-type AGB stars. Although our observations mainly trace species in the outer regions of the circumstellar environment, our conclusion matches closely that based on recent chemical equilibrium models for the inner wind of S-type stars: the atmospheric and circumstellar chemistry of S-type stars likely resembles that of C-type AGB stars much more closely than that of M-type AGB stars. Further observational investigation of the gaseous circumstellar chemistry of S-type stars is required to characterise its dependence on the atmospheric C/O. Non-equilibrium chemical models of the circumstellar environment of AGB stars need to address the particular class of S-type stars and the chemical variety that is induced by the range in atmospheric C/O.
17269. Warm dust near methanol masers
ID:
ivo://CDS.VizieR/J/A+A/410/597
Title:
Warm dust near methanol masers
Short Name:
J/A+A/410/597
Date:
21 Oct 2021
Publisher:
CDS
Description:
Continuum emission at 450 and 850{mu}m from warm dust has been mapped in the fields of 71 methanol masers. Within these fields lie 30 centimetre-wave radio continuum sources and an additional 13 methanol maser sites. Sub-mm emission is detected at all but one of the maser sites, confirming the association of methanol maser emission with deeply embedded objects. Measured bolometric luminosities confirm that methanol maser emission is an excellent signpost of high-mass star formation. Examples of nearby isolated maserless dust cores may be harbouring massive protostars at an earlier evolutionary stage.
17270. Warm IRAS sources. I. AGN candidates
ID:
ivo://CDS.VizieR/J/A+AS/70/95
Title:
Warm IRAS sources. I. AGN candidates
Short Name:
J/A+AS/70/95
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have previously shown that a blue (warm) 60 to 25{mu}m infrared colour provides a powerful parameter for discriminating between AGNs and normal galaxies and that the far-IR spectrum is therefore an efficient tool for finding new AGNs (de Grijp et al., 1985Natur.314..140D) Here we present a list of such AGN candidates based on warm IR sources from the IRAS Point Source Catalogue (PSC, Cat. II/125). Identification data and finding charts are also given. In addition the list of warm IRAS sources is supplemented by a compendium of data from the IRAS PSC on detected sources identified with previously known AGNs whose infrared spectra do not bring them within our colour selection criterion

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