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981. Carbon stars in the Galaxy and its satellites
ID:
ivo://CDS.VizieR/J/MNRAS/453/2653
Title:
Carbon stars in the Galaxy and its satellites
Short Name:
J/MNRAS/453/2653
Date:
21 Oct 2021
Publisher:
CDS
Description:
We assemble 121 spectroscopically confirmed halo carbon stars, drawn from the literature, exhibiting measurable variability in the Catalina Surveys. We present their periods and amplitudes, which are used to estimate distances from period-luminosity relationships. The location of the carbon stars - and their velocities when available - allow us to trace the streams of the Sagittarius (Sgr) dwarf spheroidal galaxy. These are compared to a canonical numerical simulation of the accretion of Sgr. We find that the data match this model well for heliocentric distances of 15-50kpc, except for a virtual lack of carbon stars in the trailing arm just north of the Galactic plane, and there is only tentative evidence of the leading arm south of the plane. The majority of the sample can be attributed to the Sgr accretion. We also find groups of carbon stars which are not part of Sgr; most of which are associated with known halo substructures. A few have no obvious attribution and may indicate new substructure. We find evidence that there may be a structure behind the Sgr leading stream apocentre, at ~100kpc, and a more distant extension to the Pisces Overdensity also at ~100kpc. We study a further 75 carbon stars for which no good period data could be obtained, and for which NIR magnitudes and colours are used to estimate distances. These data add support for the features found at distances beyond 100kpc.
982. Carbon stars IR photometry
ID:
ivo://CDS.VizieR/J/A+A/334/609
Title:
Carbon stars IR photometry
Short Name:
J/A+A/334/609
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present JHKL photometry of a sample of 150 IRAS stars in the third and fourth galactic quadrant with |b|<2{deg} selected according to their IRAS colour (0.160<=[12-25]<=1.156). We identify 27 carbon star candidates using the [12-25] vs. K-L two-colour diagram method. Among them, 10 are listed in the Stephenson's catalogue of carbon stars and 17 are new infrared carbon stars (IRCS) candidates. Their distances are found to be larger than 3kpc. These data are combined with previous data to study the space distribution of IRCS. The number density seems to be independent of the galactocentric distance (R) toward the Galactic Center and to decrease exponentially toward the anticenter. At the present stage, it is not possible to disentangle effects such as incompleteness of the sample, different space distribution law and dependence of the luminosity on metallicity. In particular, we suggest that the apparent scarcity of IRCS in the central direction of the Galaxy (R<5kpc) might be due to a selection effect. From the available data, we have found no IRCS within 1kpc of the Galactic Center.
983. Carina nebula optically identified YSOs
ID:
ivo://CDS.VizieR/J/A+A/567/A109
Title:
Carina nebula optically identified YSOs
Short Name:
J/A+A/567/A109
Date:
21 Oct 2021
Publisher:
CDS
Description:
The low obscuration and proximity of the Carina nebula make it an ideal place to study the ongoing star formation process and impact of massive stars on low-mass stars in their surroundings. To investigate this process, we have generated a new catalogue of the pre-main-sequence (PMS) stars in the Carina west (CrW) region and studied their nature and spatial distribution. We have also determined various parameters (reddening, reddening law, age, mass) which are further used to estimate the initial mass function (IMF) and K-band luminosity function (KLF) for the region under study. We obtained deep UBVRI H{alpha} photometric data of the field situated to the west of the main Carina nebula and centered around WR22. Medium-resolution optical spectroscopy of a subsample of X-ray selected objects along with archival data sets from Chandra, XMM-Newton and 2MASS surveys are used for the present study. Our spectroscopic results indicate that the majority of the X-ray sources are late spectral type stars. The region shows a large amount of differential reddening with minimum and maximum values of E(B-V) as 0.25 and 1.1mag, respectively. Our analysis reveals that the total to selective absorption ratio R_V_ is ~3.7+/-0.1 suggesting an abnormal grain size in the observed region. We identify 467 young stellar objects (YSOs) and study their characteristics. The ages and masses of the 241 optically identified YSOs range from ~0.1 to 10Myr and ~0.3 to 4.8M_{sun}_, respectively. However, the majority of them are younger than 1Myr and have masses below 2M_{sun}_. The high mass star WR22 does not seem to have contributed to the formation of YSOs in the CrW region. The initial mass function slope, Gamma in this region is found to be -1.13+/-0.20 in the mass range of 0.5<M/M_{sun}_<4.8. The K-band luminosity function slope ({alpha}) is also estimated as 0.31+/-0.01. We also performed minimum spanning tree analysis of the YSOs in this region which reveals that there are at least ten YSO cores associated with the molecular cloud and that leads to an average core radius and median branch length 0.43pc and 0.28pc, respectively.
984. Carina project IX: UBVI data of Carina variables
ID:
ivo://CDS.VizieR/J/ApJ/814/71
Title:
Carina project IX: UBVI data of Carina variables
Short Name:
J/ApJ/814/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new multiband (UBVI) time-series data of helium burning variables in the Carina dwarf spheroidal galaxy. The current sample includes 92 RR Lyrae --six of them are new identifications-- and 20 Anomalous Cepheids, one of which is new identification. The analysis of the Bailey diagram shows that the luminosity amplitude of the first overtone component in double-mode variables is located along the long-period tail of regular first overtone variables, while the fundamental component is located along the short-period tail of regular fundamental variables. This evidence further supports the transitional nature of these objects. Moreover, the distribution of Carina double-mode variables in the Petersen diagram (P_1_/P_0_ versus P_0_) is similar to metal-poor globulars (M15, M68), to the dwarf spheroidal Draco, and to the Galactic Halo. This suggests that the Carina old stellar population is metal-poor and affected by a small spread in metallicity. We use trigonometric parallaxes for five field RR Lyrae stars to provide an independent estimate of the Carina distance using the observed reddening free Period-Wesenheit [PW,(BV)] relation. Theory and observations indicate that this diagnostic is independent of metallicity. We found a true distance modulus of {mu}=20.01+/-0.02 (standard error of the mean)+/-0.05 (standard deviation) mag. We also provided independent estimates of the Carina true distance modulus using four predicted PW relations (BV, BI, VI, BVI) and we found: {mu}=(20.08+/-0.007+/-0.07)mag, {mu}=(20.06+/-0.006+/-0.06)mag, {mu}=(20.07+/-0.008+/-0.08)mag, and {mu}=(20.06+/-0.006+/-0.06)mag. Finally, we identified more than 100 new SX Phoenicis stars that together with those already known in the literature (340) make Carina a fundamental laboratory for constraining the evolutionary and pulsation properties of these transitional variables.
985. Carina Spiral Feature ubvybeta photometry
ID:
ivo://CDS.VizieR/J/A+A/410/523
Title:
Carina Spiral Feature ubvybeta photometry
Short Name:
J/A+A/410/523
Date:
21 Oct 2021
Publisher:
CDS
Description:
A data-base collating all uvby{beta} photometry available at present for O-B9 stars brighter than 10th visual magnitude in the field of the Carina Spiral Feature is presented. The completeness and homogeneity of the data-base are discussed.
986. Carlsberg Meridian Catalog 14 (CMC14)
ID:
ivo://CDS.VizieR/I/304
Title:
Carlsberg Meridian Catalog 14 (CMC14)
Short Name:
I/304
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Carlsberg Meridian Telescope (formerly the Carlsberg Automatic Meridian Circle) is dedicated to carrying out high-precision optical astrometry. It underwent a major upgrade in March 1999, with the installation of a 2kx2k CCD camera was installed with a Sloan r' filter operating in a drift scan mode. With the new system, the magnitude limit is 17 (r'mag) and the positional accuracy is in the range 35 to 100 mas. The resulting survey is aimed to provide an astrometric and photometric catalogue in the declination range -30 to +50 degrees. This catalogue is the result of all the observations made between March 1999 and October 2005 in the declination band -30 to +50 -- minus a gap between 5h30m and 10h30m for declinations south of -15. It contains 95,858,475 stars, plus 8,046,291 in the rejected files. Further information can be found in the documentation (cmc14doc.pdf) or at the web site http://www.ast.cam.ac.uk/~dwe/SRF/camc.html . It supersedes the previous versions (Cat. I/282) A dedicated remote query program (findcmc14) can be downloaded from http://cdsweb.u-strasbg.fr/doc/cdsclient.html
987. Carlsberg Meridian Catalog 15 (CMC15)
ID:
ivo://CDS.VizieR/I/327
Title:
Carlsberg Meridian Catalog 15 (CMC15)
Short Name:
I/327
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Carlsberg Meridian Telescope (formerly the Carlsberg Automatic Meridian Circle) is dedicated to carrying out high-precision optical astrometry. It underwent a major upgrade in March 1999, with the installation of a 2kx2k CCD camera was installed with a Sloan r' filter operating in a drift scan mode. With the new system, the magnitude limit is 17 (r'mag) and the positional accuracy is in the range 35 to 100 mas. The resulting survey is aimed to provide an astrometric and photometric catalogue in the declination range -40 to +50 degrees. This catalogue is the result of all the observations made between March 1999 and March 2011 in the declination band -40 to +50 degrees. Further information can be found in the documentation at the web site http://svo2.cab.inta-csic.es/vocats/cmc15/
988. CARMENES input catalogue of M dwarfs. V.
ID:
ivo://CDS.VizieR/J/A+A/642/A115
Title:
CARMENES input catalogue of M dwarfs. V.
Short Name:
J/A+A/642/A115
Date:
02 Mar 2022 00:04:08
Publisher:
CDS
Description:
The relevance of M dwarfs in the search for potentially habitable Earth-size planets has grown significantly in the last years. In our on-going effort of comprehensively and accurately characterising confirmed and potential planet-hosting M dwarfs, in particular for the CARMENES survey, we have carried out a comprehensive multi-band photometric analysis involving spectral energy distributions, luminosities, absolute magnitudes, colours, and spectral types, from which we have derived basic astrophysical parameters. We have carefully compiled photometry in 20 passbands from the far-ultraviolet to the mi-infrared, and combined it with the latest parallactic distances and close-multiplicity information, mostly from Gaia DR2, of a sample of 2479 K5 V to L8 stars and ultracool dwarfs, including 2210 nearby, bright, M dwarfs. For that, we have made extensive use of Virtual Observatory tools. We have homogeneously computed accurate bolometric luminosities, effective temperatures of 1843 single stars, derived their radii and masses, studied the impact of metallicity, and compared our results with the literature. The over 40 000 individually-inspected magnitudes, together with the basic data and derived parameters of the stars, one by one and averaged by spectral type, have been made public to the astronomical community. In addition, we have reported 40 new close multiple systems and candidates (rho<3.3-arcsec) and 36 overluminous stars that are assigned to young Galactic populations. In the new era of exoplanet searches around M dwarfs via transit (e.g., TESS, PLATO) and radial velocity (e.g., CARMENES, NIRPS+HARPS), this work is of fundamental importance for stellar and, thus, planetary parameter determination.
989. Carnegie-Chicago Hubble Program: RR Lyrae NIR obs.
ID:
ivo://CDS.VizieR/J/ApJ/869/82
Title:
Carnegie-Chicago Hubble Program: RR Lyrae NIR obs.
Short Name:
J/ApJ/869/82
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometry of 30 Galactic RR Lyrae variables taken with HST WFC3/IR for the Carnegie-Chicago Hubble Program. These measurements form the base of the distance-ladder measurements that comprise a pure Population II base to a measurement of Ho at an accuracy of 3%. These data are taken with the same instrument and filter (F160W) as our observations of RR Lyrae stars in external galaxies so as to minimize sources of systematic error in our calibration of the extragalactic distance scale. We calculate mean magnitudes based on one to three measurements for each RR Lyrae star using star-by-star templates generated from densely time-sampled data at optical and midinfrared wavelengths. We use four RR Lyrae stars from our sample with well-measured HST parallaxes to determine a zero-point. This zero-point will soon be improved with the large number of precise parallaxes to be provided by Gaia. We also provide preliminary calibration with the TGAS and Gaia DR2 data, and all three zero points are in agreement, to within their uncertainties.
990. Carnegie-Irvine Galaxy Survey VII. S0 galaxies
ID:
ivo://CDS.VizieR/J/ApJ/862/100
Title:
Carnegie-Irvine Galaxy Survey VII. S0 galaxies
Short Name:
J/ApJ/862/100
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using high-quality optical images from the Carnegie-Irvine Galaxy Survey, we perform multicomponent decompositions of S0 galaxies (S0s) to derive accurate structural parameters to constrain their physical origin. Many S0s do not host prominent bulges. S0s have a broad distribution of bulge-to-total ratios (B/T) and Sersic indices (n), with average values of B/T=0.34+/-0.15 and n=2.62+/-1.02, qualitatively consistent with the notion that S0s define a parallel sequence with and may have evolved from spiral galaxies. This is further reinforced by the incidence of bars and lenses in S0s, which, when compared with the statistics in spirals, supports the idea that lenses are demised bars. However, despite their wide range of prominence, the bulges of S0s form a surprisingly uniform sequence on both the Kormendy and fundamental plane relations. There is no evidence for population dichotomy or other indications of differentiation into classical and pseudo bulges. Most of the S0s reside in the field and in groups; cluster environment is not a necessary condition for S0 production. The properties of S0 bulges show little correlation with environmental indicators, after the dependence of galaxy stellar mass on environment is taken into account. As the bulges of late-type spirals and S0s are intrinsically different, and environmental effects that may account for such evolution appear to be minimal, we conclude that late- type spirals are not plausible progenitors of S0s. The bulges of S0s likely formed at an early epoch, after which secular processes contributed little to their subsequent evolution.