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- ID:
- ivo://CDS.VizieR/J/A+AS/139/513
- Title:
- 1975-1995 V1794 Cyg UBVRI photometry
- Short Name:
- J/A+AS/139/513
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Six years of new photometry of V 1794 Cyg is combined with the previously published data. These data are processed into two decades of homogeneous standard Johnson UBVRI photometry, which contains 1207, 1837, 1927, 867 and 75 observations in U, B, V, R and I, respectively.
- 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.
- 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.
- 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.
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/612/A7
- Title:
- Vela Junior (RX J0852.0-4622) HESS image
- Short Name:
- J/A+A/612/A7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study {gamma}-ray emission from the shell-type supernova remnant (SNR) RX J0852.0-4622 to better characterize its spectral properties and its distribution over the SNR. The analysis of an extended High Energy Spectroscopic System (H.E.S.S.) data set at very high energies (E>100GeV) permits detailed studies, as well as spatially resolved spectroscopy, of the morphology and spectrum of the whole RX J0852.0-4622 region. The H.E.S.S. data are combined with archival data from other wavebands and interpreted in the framework of leptonic and hadronic models. The joint Fermi-LAT-H.E.S.S. spectrum allows the direct determination of the spectral characteristics of the parent particle population in leptonic and hadronic scenarios using only GeV-TeV data. An updated analysis of the H.E.S.S. data shows that the spectrum of the entire SNR connects smoothly to the high-energy spectrum measured by Fermi-LAT. The increased data set makes it possible to demonstrate that the H.E.S.S. spectrum deviates significantly from a power law and is well described by both a curved power law and a power law with an exponential cutoff at an energy of E_cut_=(6.7+/-1.2_stat_+/-1.2_syst_)TeV. The joint Fermi-LAT-H.E.S.S. spectrum allows the unambiguous identification of the spectral shape as a power law with an exponential cutoff. No significant evidence is found for a variation of the spectral parameters across the SNR, suggesting similar conditions of particle acceleration across the remnant. A simple modeling using one particle population to model the SNR emission demonstrates that both leptonic and hadronic emission scenarios remain plausible. It is also shown that at least a part of the shell emission is likely due to the presence of a pulsar wind nebula around PSR J0855-4644.
20598. Vela OB2 members
- ID:
- ivo://CDS.VizieR/J/A+A/621/A115
- Title:
- Vela OB2 members
- Short Name:
- J/A+A/621/A115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Vela OB2 association is a group of 10Myr stars exhibiting a complex spatial and kinematic substructure. The all-sky Gaia DR2 catalogue contains proper motions, parallaxes (a proxy for distance) and photometry that allow us to separate the various components of Vela OB2. We characterise the distribution of the Vela OB2 stars on a large spatial scale, and study its internal kinematics and dynamic history. We make use of Gaia DR2 astrometry and published Gaia-ESO Survey data. We apply an unsupervised classification algorithm to determine groups of stars with common proper motions and parallaxes. We find that the association is made up of a number of small groups, with a total current mass over 2330M_{sun}_. The three-dimensional distribution of these young stars trace the edge of the gas and dust structure known as the IRAS Vela Shell across 180 pc and shows clear signs of expansion. We propose a common history for Vela OB2 and the IRAS Vela Shell. The event that caused the expansion of the shell happened before the Vela OB2 stars formed, imprinted the expansion in the gas the stars formed from, and most likely triggered star formation.
- ID:
- ivo://CDS.VizieR/J/MNRAS/326/473
- Title:
- Vel. Distribution of low-luminosity E galaxies
- Short Name:
- J/MNRAS/326/473
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The shape of the line-of-sight velocity distribution (LOSVD) is measured for a sample of 14 elliptical galaxies, predominantly low-luminosity ellipticals. The sample is dominated by galaxies in the Virgo cluster but also contains ellipticals in nearby groups and low density environments. The parameterization of the LOSVD due to Gerhard and van der Marel & Franx is adopted, which measures the asymmetrical and symmetrical deviations of the LOSVD from a Gaussian by the amplitudes h3 and h4 of the Gauss-Hermite series. Rotation, velocity dispersion, h3 and h4 are determined as a function of radius for both major and minor axes using the Fourier Correlation Quotient method of Bender (1990). Galaxy spectra are rebinned in the direction of the spectroscopic slit to a minimum signal-to-noise ratio (S/N) of 60 per angstrom. Rotation and velocity dispersion are determined separately for S/N = 30 per angstrom.
- 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.
