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4541. VIRMOS deep imaging survey. VVDS-F02 catalog
ID:
ivo://CDS.VizieR/II/286
Title:
VIRMOS deep imaging survey. VVDS-F02 catalog
Short Name:
II/286
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Franco-Italian VIRMOS project has delivered the VIMOS spectrograph for the European Southern Observatory Very Large Telescope (ESO-VLT). VIMOS is a VIsible imaging Multi-Object Spectrograph with outstanding multiplex capabilities: with 10 arcsec slits, spectra can be taken of 600 objects simultaneously. In integral field mode, a 6400-fibre Integral Field Unit (IFU) provides spectroscopy for all objects covering a 54x54arcsec^2^ area.
4542. VIS3COS. III. Galaxy spectra
ID:
ivo://CDS.VizieR/J/A+A/633/A70
Title:
VIS3COS. III. Galaxy spectra
Short Name:
J/A+A/633/A70
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present spectroscopic observations of 466 galaxies in and around a superstructure at z~0.84 targeted by the VIMOS Spectroscopic Survey of a Supercluster in the COSMOS eld (VIS3COS). We use [OII]3727, H{delta}, and Dn4000 to trace recent, medium-, and long-term star formation histories and investigate the eect of stellar mass and local environment on them. By studying trends in individual and composite galaxy spectra, we find that stellar mass and environment play a role in the observed galactic properties. Galaxies with low stellar mass (10<log10(M*/M_{sun}_)<10.5) in the eld show the strongest H{delta} absorption. Similarly, the massive population (log10(M*/M_{sun}_) > 11) shows an increase in H absorption strengths in intermediate-density environments (e.g. filaments). Galaxies with intermediate stellar mass (10.5<log10(M*/M_{sun}_)<11) have similar H{delta} absorption proles in all environments, but show an indication of enhanced [OII] emission in intermediate-density environments. This indicates that field galaxies with low stellar mass and lament galaxies with high stellar mass are more likely to have experienced a recent burst of star formation, while galaxies of the intermediate stellar-mass show an increase of star formation at lament-like densities. We also find that the median [OII] equivalent width (|EW[OII]|) decreases from 27+/-2{AA} to 2.0^+0,5^_-0.4_{AA} and Dn4000 increases from 1.09+/-0.01 to 1.56+/-0.03 with increasing stellar mass (from ~10^9.25^ to ~10^11.35^M_{sun}_). For the dependence on the environment, we find that at fixed stellar mass, |EW[OII]| is tentatively lower in environments with higher density. We find for Dn4000 that the increase with stellar mass is sharper in denser environments, which indicates that these environments may accelerate galaxy evolution. Moreover, we find higher Dn4000 values in denser environments at fixed stellar mass, suggesting that galaxies are on average older and/or more metal rich in these dense environments. This set of tracers depicts a scenario where the most massive galaxies have, on average, the lowest specic star formation rates and the oldest stellar populations (age>~1Gyr, showing a mass-downsizing eect). We also hypothesize that the observed increase in star formation (higher EW[OII], higher specic star formation rate) at intermediate densities may lead to quenching because we find that the quenched fraction increases sharply from the lament to cluster-like regions at similar stellar masses.
4543. Visible obs. of GOT C+ Northern sightlines
ID:
ivo://CDS.VizieR/J/ApJ/858/111
Title:
Visible obs. of GOT C+ Northern sightlines
Short Name:
J/ApJ/858/111
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using visible, radio, microwave, and submillimeter data, we study several lines of sight toward stars generally closer than 1kpc on a component-by-component basis. We derive the component structure seen in absorption at visible wavelengths from CaII, CaI, KI, CH, CH+, and CN and compare it to emission from HI, CO and its isotopologues, and C+ from the GOT C+ (Galactic Observations of Terahertz C+) survey (Langer+ 2010A&A...521L..17L). The correspondence between components in emission and absorption helps create a more unified picture of diffuse atomic and molecular gas in the interstellar medium. We also discuss how these tracers are related to the CO-dark H2 gas probed by C+ emission and discuss the kinematic connections among the species observed.
4544. VISTA and Subaru/HSC obs. of Upper Scorpius
ID:
ivo://CDS.VizieR/J/MNRAS/503/2265
Title:
VISTA and Subaru/HSC obs. of Upper Scorpius
Short Name:
J/MNRAS/503/2265
Date:
21 Oct 2021
Publisher:
CDS
Description:
We aim at identifying very low-mass isolated planetary-mass member candidates in the nearest OB association to the Sun, Upper Scorpius (145pc; 5-10Myr), to constrain the form and shape of the luminosity function and mass spectrum in this regime. We conducted a deep multi-band (Y=21.2, J=20.5, Z=22.0mag) photometric survey of six square degrees in the central region of Upper Scorpius. We extend the current sequence of astrometric and spectroscopic members by about two magnitudes in Y and one magnitude in J, reaching potentially T-type free-floating members in the association with predicted masses below 5 Jupiter masses, well into the planetary-mass regime. We extracted a sample of 57 candidates in this area and present infrared spectroscopy confirming two of them as young L-type members with characteristic spectral features of 10Myr-old brown dwarfs. Among the 57 candidates, we highlight 10 new candidates fainter than the coolest members previously confirmed spectroscopically. We do not see any obvious sign of decrease in the mass spectrum of the association, suggesting that star processes can form substellar objects with masses down to 4-5 Jupiter masses.
4545. Visual binary orbits and masses
ID:
ivo://CDS.VizieR/J/A+A/341/121
Title:
Visual binary orbits and masses
Short Name:
J/A+A/341/121
Date:
21 Oct 2021
Publisher:
CDS
Description:
The paper gives orbits and masses for some 200 nearby visual binaries, as derived from combining ground-based and Hipparcos data. Table 6 gives identifications and notes, and points to the detailed data in Table 1 (short-P systems with mass-ratio from the Hipparcos observations), Table 3 (mass-uncertainty below 10%) or Table 4 (mass-uncertainty above 10%).
4546. Visual Double Stars with Early-Type Primaries. IV
ID:
ivo://CDS.VizieR/II/127
Title:
Visual Double Stars with Early-Type Primaries. IV
Short Name:
II/127
Date:
21 Oct 2021
Publisher:
CDS
Description:
Astrophysical parameters (MK class, colour excess, absolute magnitude, distance, effective temperature, mass and age) are derived from calibrations of the uvbybeta indices for the members of 253 double stars with O or B type primaries and faint secondaries. The photometric spectral classification is compared to the MK classes and the agreement is very good. The derived data together with spectroscopic and JHKL data indicate that these stars are likely to be members of physical systems. For 90% of the physical pairs the projected separations between the components is less than 25,000 AU. A majority of the physical secondaries are late type stars and 50% of them are contracting towards the zero-age main-sequence (ZAMS).
4547. Visual photometry for the Be star {mu} Centauri
ID:
ivo://CDS.VizieR/J/AJ/156/174
Title:
Visual photometry for the Be star {mu} Centauri
Short Name:
J/AJ/156/174
Date:
21 Oct 2021
Publisher:
CDS
Description:
With the aim of contributing to the understanding of the disk formation process in Be stars, we pursued a one-year spectroscopic observing campaign of the Be star {mu} Centauri in the L-band, using VLT/ISAAC. We present the nine near-IR spectra we obtained in an epoch of relative photometric quiescence prior to an outburst of {Delta}V=0.4 magnitude. Visual estimates during the epoch of our L-band spectroscopy are also presented for the first time, together with the unpublished complete visual light curve between the years 1998 and 2014. We observe significant and monotonic changes in emission line strength of Bracket-{alpha} and Pfund-{gamma} lines relative to Humphreys lines, and also in the continuum slope. We interpret these observed changes in terms of important changes to the column density of the line emitting regions, moving from an optically thin to an optically thick stage just prior to a major outburst. For each observing date, we provide estimates for the column density and relative extension of the line emitting region. If the changes observed toward the end of our observing campaign were related to mass-loss changes from the central star, they would correspond to an increase in a factor of two in the mass of the disk in the innermost region. If related to the visual outburst observed one month later, the variability observed in our spectra would be the first detection of the early disk formation process in the L-band.
4548. VJHK and SDSS photometry of DA white dwarfs
ID:
ivo://CDS.VizieR/J/AJ/132/1221
Title:
VJHK and SDSS photometry of DA white dwarfs
Short Name:
J/AJ/132/1221
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have calibrated four major ground-based photometric systems with respect to the Hubble Space Telescope (HST) absolute flux scale, which is defined by Vega and four fundamental DA white dwarfs. These photometric systems include the Johnson-Kron-Cousins UBVRI, the Stroemgren uvby filters, the Two Micron All Sky Survey JHKs, and the Sloan Digital Sky Survey ugriz filters. Synthetic magnitudes are calculated from model white dwarf spectra folded through the published filter response functions; these magnitudes in turn are absolutely calibrated with respect to the HST flux scale. Effective zero-magnitude fluxes and zero-point offsets of each system are determined. In order to verify the external observational consistency, as well as to demonstrate the applicability of these definitions, the synthetic magnitudes are compared with the respective observed magnitudes of larger sets of DA white dwarfs that have well-determined effective temperatures and surface gravities and span a wide range in both of these parameters.
4549. V360 Lac spectroscopy
ID:
ivo://CDS.VizieR/J/A+A/455/1037
Title:
V360 Lac spectroscopy
Short Name:
J/A+A/455/1037
Date:
21 Oct 2021
Publisher:
CDS
Description:
We include existing photometric and spectroscopic material with new observations in a detailed study of the Be+F binary V360 Lac. We used the programs FOTEL and KOREL to derive an improved linear ephemeris and to disentangle the line profiles of both binary components and telluric lines. The BINSYN software suite (described in the paper) is used to calculate synthetic light curves and spectra to fit the UBV photometry, an IUE spectrum, blue and red ground-based spectra, and observed radial-velocity curves.
4550. V441 Lac VRI light curves
ID:
ivo://CDS.VizieR/J/other/NewA/36.32
Title:
V441 Lac VRI light curves
Short Name:
J/other/NewA/36.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first multi-color VRI CCD light curves of a short-period eclipsing binary star v441 Lac in this paper. We obtained our light curves on Oct. 4 and 8, 2013 at Xinglong station of National Astronomical Observatories, China. We updated the ephemeris of V441 Lac based on three new minima derived by our new observational data together with previously available light curve minima. By fitting the O-C (observed minus calculated) values of the minima, we found that the orbital period of V441 Lac exhibits an increasing trend of View the dP/dt=5.67(0.35)x10^-7^days/year, which might be explained by mass transfer from the secondary component to the primary one, or angular momentum exchange by magnetic activities. We also obtained the photometric orbital parameters with the Wilson & Devinney program. Our final result shows that the V441 Lac system is a semi-detached binary with the secondary component filling roche lobe.