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7741. V2480 Cyg V and R light curves
ID:
ivo://CDS.VizieR/J/other/NewA/53.1
Title:
V2480 Cyg V and R light curves
Short Name:
J/other/NewA/53.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the photometric analysis of the detached eclipsing binary V2480 Cyg. After taking the photometric data, the light curve was analyzed in PHOEBE software, which uses the Wilson-Devinney code. Due to the observed O'Connell (1951PRCO....2...85O) effect in light curve, we introduce a spotted model with 3 spots on the components, and the exact parameters of the system have been achieved. The main parameters of the system were calculated as about q_ptm_=1.7, T_eff1_=8075K and T_eff2_=3829K.
7742. VEGAS: A VST Early-type GAlaxy Survey
ID:
ivo://CDS.VizieR/J/A+A/581/A10
Title:
VEGAS: A VST Early-type GAlaxy Survey
Short Name:
J/A+A/581/A10
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the VST Early-type GAlaxy Survey (VEGAS), which is designed to obtain deep multiband photometry in g, r, i, of about one hundred nearby galaxies down to 27.3, 26.8, and 26mag/arcsec^2^ respectively, using the ESO facility VST/OmegaCAM. The goals of the survey are 1) to map the light distribution up to ten effective radii, r_e_; 2) to trace color gradients and surface brightness fluctuation gradients out to a few r_e_ for stellar population characterization; and 3) to obtain a full census of the satellite systems (globular clusters and dwarf galaxies) out to 20% of the galaxy virial radius. The external regions of galaxies retain signatures of the formation and evolution mechanisms that shaped them, and the study of nearby objects enables a detailed analysis of their morphology and interaction features. To clarify the complex variety of formation mechanisms of early-type galaxies (ETGs), wide and deep photometry is the primary observational step, which at the moment has been pursued with only a few dedicated programs. The VEGAS survey has been designated to provide these data for a volume-limited sample with exceptional image quality. In this commissioning photometric paper we illustrate the capabilities of the survey using g- and i-band VST/OmegaCAM images of the nearby galaxy NGC 4472 and of smaller ETGs in the surrounding field. Our surface brightness profiles reach rather faint levels and agree excellently well with previous literature. Genuine new results concern the detection of an intracluster light tail in NGC 4472 and of various substructures at increasing scales. We have also produced extended (g-i) color profiles. The VST/OmegaCAM data that we acquire in the context of the VEGAS survey provide a detailed view of substructures in the optical emission from extended galaxies, which can be as faint as a hundred times below the sky level.
7743. VEGAS-SSS photometry of NGC3115
ID:
ivo://CDS.VizieR/J/A+A/576/A14
Title:
VEGAS-SSS photometry of NGC3115
Short Name:
J/A+A/576/A14
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of globular clusters (GCs) and other small stellar systems (SSSs) in the field of NGC 3115, observed as part of the ongoing wide-field imaging survey VEGAS, carried out with the 2.6m VST telescope. We used deep g and i observations of NGC 3115, a well-studied lenticular galaxy that is covered excellently well in the scientific literature. This is fundamental to test the methodologies, verify the results, and probe the capabilities of the VEGAS-SSS. Leveraging the large field of view of the VST allowed us to accurately study the distribution and properties of SSSs as a function of galactocentric distance, well beyond ~20 galaxy effective radii, in a way that is rarely possible. Our analysis of colors, magnitudes, and sizes of SSS candidates confirms the results from existing studies, some of which were carried out with 8-10m class telescopes, and further extends them to previously unreached galactocentric distances with similar accuracy. In particular, we find a color bimodality for the GC population and a de Vaucouleurs profile for the surface density of GCs similar to the galaxy light profile. The radial color gradient of blue and red GCs previously found, for instance, by the SLUGGS survey with Subaru and Keck data, is further extended out to the largest galactocentric radii inspected, ~65kpc. In addition, the surface density profiles of blue and red GCs taken separately are well approximated by a r1/4 density profile, with the fraction of blue GCs being slightly larger at larger radii. We do not find hints of a trend for the red GC subpopulation and for the GC turnover magnitude to vary with radius, but we observe a ~0.2mag difference in the turnover magnitude of the blue and red GC subpopulations. Finally, from inspecting SSS sizes and colors, we obtain a list of ultracompact dwarf galaxies and GC candidates suitable for future spectroscopic follow-up. In conclusion, our study shows i) the reliability of the methodologies developed to study SSSs in the field of bright early-type galaxies, and ii) the great potential of the VEGAS survey to produce original results on SSSs science, mainly thanks to the wide-field imaging adopted.
7744. Vega-type and PMS stars UBVRI photo-polarimetry
ID:
ivo://CDS.VizieR/J/A+A/379/564
Title:
Vega-type and PMS stars UBVRI photo-polarimetry
Short Name:
J/A+A/379/564
Date:
21 Oct 2021
Publisher:
CDS
Description:
This table presents optical UBVRI broadband photo-polarimetry of the EXPORT sample obtained at the 2.5m Nordic Optical Telescope. The database consists of multi-epoch photo-polarimetry of 68 pre-main-sequence and main-sequence stars.
7745. Velocities and BR photometry in LMC
ID:
ivo://CDS.VizieR/J/MNRAS/339/701
Title:
Velocities and BR photometry in LMC
Short Name:
J/MNRAS/339/701
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a large spectroscopic survey of the LMC, consisting of more than 1300 radial velocities measured accurately with the 2dF instrument during three observing compaigns 1999-2002. In this sample, no evidence is found for any extraneous, kinematically distinct population over the expected LMC and Galactic components. We discuss the significance of this finding for the LMC self-lensing models. The sample was randomly selected from three APM photographic plates with 16<=R<=18mag and -1.0<=Bj-R<=2.5mag. The fields were centered on previous microlensing events. The 1200V grating was used with 1.1{AA} per pixel resolution over 4625-5765{AA}. The zero point of the velocity of LMC K-type stars is set by cross-correlating with a K-type standard star. For sample stars of other spectral type we assume no systematic change of the peak of velocity distribution with spectral type.
7746. Velocities and BR photometry of Abell 1995
ID:
ivo://CDS.VizieR/J/A+A/547/A44
Title:
Velocities and BR photometry of Abell 1995
Short Name:
J/A+A/547/A44
Date:
21 Oct 2021
Publisher:
CDS
Description:
Abell 1995 is a puzzling galaxy cluster hosting a powerful radio halo, but it has not yet been recognized as a obvious cluster merger, as usually expected for clusters with diffuse radio emission. We aim at an exhaustive analysis of the internal structure of Abell 1995 to verify that this cluster is really dynamically relaxed, as reported in previous studies. We base our analysis on new and archival spectroscopic and photometric data for 126 galaxies in the field of Abell 1995. The study of the hot intracluster medium was performed on X-ray archival data.
7747. Velocities and CMT2 photometry in globular M92
ID:
ivo://CDS.VizieR/J/AJ/133/1041
Title:
Velocities and CMT2 photometry in globular M92
Short Name:
J/AJ/133/1041
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the determination of high-accuracy radial velocities for 306 members of the globular cluster M92 using the Hydra multiobject spectrograph on the WIYN telescope. We have concentrated on stars outside of the central region of the cluster, located up to 14.4' from the cluster center. Candidate members were selected for spectroscopy based on a photometric metallicity index determined from three-band Washington photometry, also obtained with the WIYN telescope.
7748. Velocities and light curves of V350 Sgr
ID:
ivo://CDS.VizieR/J/AJ/142/87
Title:
Velocities and light curves of V350 Sgr
Short Name:
J/AJ/142/87
Date:
21 Oct 2021
Publisher:
CDS
Description:
"The Cepheid Mass Problem" is one of the fundamental tests of the understanding of stellar evolution. One of the foundations of measured masses for Cepheids for this question is binary orbits. V350 Sgr is a classical Cepheid in a binary system. New radial velocity data for the system have been obtained over the last several years, and are used to update the orbit. The secondary in the system has previously had its orbital velocity amplitude measured in the ultraviolet with the Hubble Space Telescope. This amplitude has been combined with the new orbit and the adopted mass of the secondary resulting in a Cepheid mass of 5.0+/-0.8M_{sun}_.
7749. Velocities and photometry in NGC 2112
ID:
ivo://CDS.VizieR/J/MNRAS/386/1625
Title:
Velocities and photometry in NGC 2112
Short Name:
J/MNRAS/386/1625
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on a new, wide-field (20x20arcmin^2^), multicolour (UBVI), photometric campaign in the area of the nearby old open cluster NGC 2112. At the same time, we provide medium-resolution spectroscopy of 35 (and high-resolution of additional 5) red giant and turn-off stars. This material is analysed with the aim to update the fundamental parameters of this traditionally difficult cluster, which is very sparse and suffers from heavy field star contamination. Among the 40 stars with spectra, we identified 21 bona fide radial velocity members which allow us to put more solid constraints on the cluster's metal abundance, long suggested to be as low as the metallicity of globulars. As indicated earlier by us on a purely photometric basis, the cluster [Fe/H] abundance is slightly supersolar ([Fe/H]=0.16+/-0.03) and close to the Hyades value, as inferred from a detailed abundance analysis of three of the five stars with higher resolution spectra. Abundance ratios are also marginally supersolar. Based on this result, we revise the properties of NGC 2112 using stellar models from the Padova and Yale-Yonsei groups.
7750. Velocities and photometry in Trumpler 20
ID:
ivo://CDS.VizieR/J/A+A/561/A94
Title:
Velocities and photometry in Trumpler 20
Short Name:
J/A+A/561/A94
Date:
21 Oct 2021
Publisher:
CDS
Description:
Trumpler 20 is an old open cluster (OC) located toward the Galactic centre, at about 3kpc from the Sun and ~7kpc from the Galactic centre. Its position makes this cluster particularly interesting in the framework of the chemical properties of the Galactic disc because very few old OCs reside in the inner part of the disc. For this reason it has been selected as a cluster target of the Gaia-ESO Survey, and spectra of many stars in the main sequence and red clump phases are now available. Moreover, although it has been studied by several authors in the past, no consensus on the evolutionary status of Tr 20 has been reached. The heavy contamination of field stars (the line of sight of Tr 20 crosses the Carina spiral arm) complicates the correct interpretation. Another interesting aspect of the cluster is that it shows a broadened main sequence turn-off and a prominent and extended red clump, characteristics that are not easily explained by classical evolutionary models. Exploiting both spectroscopic information from the Gaia-ESO Survey (and the ESO archive) and literature photometry, we obtain a detailed and accurate analysis of the properties of the cluster. We make use of the first accurate metallicity measurement ever obtained from several spectra of red clump stars, and of cluster membership determination using radial velocities. According to the evolutionary models adopted, we find that Tr 20 has an age in the range 1.35-1.66Gyr, an average reddening E(B-V) in the range 0.31-0.35mag, a distance modulus (m-M)_0_ between 12.64 and 12.72mag. The spectroscopic metallicity is [Fe/H]=+0.17dex. We discuss the structural properties of the object and constrain possible hypotheses for its broadened upper main sequence, by estimating the effect of differential reddening, and its extended red clump.