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1581. DES Y3 substellar LT and M catalogs
ID:
ivo://CDS.VizieR/J/MNRAS/489/5301
Title:
DES Y3 substellar LT and M catalogs
Short Name:
J/MNRAS/489/5301
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we present a catalogue of 11745 brown dwarfs with spectral types ranging from L0 to T9, photometrically classified using data from the Dark Energy Survey (DES) year 3 release matched to the Vista Hemisphere Survey (VHS) DR3 and Wide-field Infrared Survey Explorer (WISE) data, covering ~2400deg^2^ up to i_AB_=22. The classification method follows the same photo-type method previously applied to SDSS-UKIDSS-WISE data. The most significant difference comes from the use of DES data instead of SDSS, which allow us to classify almost an order of magnitude more brown dwarfs than any previous search and reaching distances beyond 400 parsecs for the earliest types. Next, we also present and validate the GalmodBD simulation, which produces brown dwarf number counts as a function of structural parameters with realistic photometric properties of a given survey. We use this simulation to estimate the completeness and purity of our photometric LT catalogue down to i_AB_=22, as well as to compare to the observed number of LT types. We put constraints on the thin disk scale height for the early L (L0-L3) population to be around 450 parsecs, in agreement with previous findings. For completeness, we also publish in a separate table a catalogue of 20863 M dwarfs that passed our colour cut with spectral types greater than M6. Both the LT and the late M catalogues are found at https://des.ncsa.illinois.edu/releases/other/y3-mlt.
1582. Detached eclipsing binaries MITSuME photometry
ID:
ivo://CDS.VizieR/J/A+A/622/A114
Title:
Detached eclipsing binaries MITSuME photometry
Short Name:
J/A+A/622/A114
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of the combined photometric and spectroscopic analysis of three detached eclipsing binaries (DEBs), the secondary components of which are not visible or are very hard to identify in the optical spectra - ASAS J052743-0359.7, ASAS J065134-2211.5, and ASAS J073507-0905.7. The first one is the known visual binary ADS~4022, and we found that it is a quadruple system composed of two spectroscopic binaries, one of which shows eclipses.
1583. Detached eclipsing binaries with Gaia parallaxes
ID:
ivo://CDS.VizieR/J/ApJ/872/85
Title:
Detached eclipsing binaries with Gaia parallaxes
Short Name:
J/ApJ/872/85
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a sample of 81 Galactic, detached eclipsing binary stars we investigated the global zero-point shift of their parallaxes with the Gaia Data Release 2 (DR2) parallaxes. The stars in the sample lay in a distance range of 0.04-2kpc from the Sun. The photometric parallaxes {omega}_Phot_ of the eclipsing binaries were determined by applying a number of empirical surface brightness-color (SBC) relations calibrated on optical-infrared colors. For each SBC relation we calculated the individual differences d{varpi}_i_=({varpi}_Gaia_-{varpi}_Phot_)_i_ and then we calculated unweighted and weighted means. As the sample covers the whole sky we interpret the weighted means as the global shifts of the Gaia DR2 parallaxes with respect to our eclipsing binary sample. Depending on the choice of the SBC relation the shifts vary from -0.094 to -0.025mas. The weighted mean of the zero-point shift from all colors and calibrations used is d{omega}=-0.054+/-0.024mas. However, the SBC relations based on (B-K) and (V-K) colors, which are the least reddening dependent and have the lowest intrinsic dispersions, give a zero-point shift of d{omega}=-0.031+/-0.011mas in full agreement with results obtained by Lindegren+ (2018A&A...616A...2L) and Arenou+ (2018A&A...616A..17A). Our result confirms the global shift of Gaia DR2 parallaxes of d{omega}=-0.029mas reported by the Gaia team, but we do not confirm the larger zero-point shift reported by a number of follow-up papers.
1584. Detached M dwarf eclipsing binaries in WTS
ID:
ivo://CDS.VizieR/J/MNRAS/426/1507
Title:
Detached M dwarf eclipsing binaries in WTS
Short Name:
J/MNRAS/426/1507
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of 16 detached M dwarf eclipsing binaries (MEBs) with J<16mag and provide a detailed characterization of three of them, using high-precision infrared light curves from the WFCAM Transit Survey (WTS). Such systems provide the most accurate and model-independent method for measuring the fundamental parameters of these poorly understood yet numerous stars, which currently lack sufficient observations to precisely calibrate stellar evolution models.
1585. Detailed analysis of cool WDs in the SDSS
ID:
ivo://CDS.VizieR/J/ApJS/190/77
Title:
Detailed analysis of cool WDs in the SDSS
Short Name:
J/ApJS/190/77
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical spectroscopy and near-infrared photometry of 126 cool white dwarfs (WDs) in the Sloan Digital Sky Survey (SDSS DR3). Our sample includes high proper motion targets selected using the SDSS and USNO-B astrometry and a dozen previously known ultracool WD candidates. Our optical spectroscopic observations demonstrate that a clean selection of large samples of cool WDs in the SDSS (and the SkyMapper, Pan-STARRS, and the Large Synoptic Survey Telescope data sets) is possible using a reduced proper motion diagram and a tangential velocity cut-off (depending on the proper motion accuracy) of 30km/s. Our near-infrared observations reveal eight new stars with significant absorption. We use the optical and near-infrared photometry to perform a detailed model atmosphere analysis. More than 80% of the stars in our sample are consistent with either pure hydrogen or pure helium atmospheres. However, the eight stars with significant infrared absorption and the majority of the previously known ultracool WD candidates are best explained with mixed hydrogen and helium atmosphere models. The age distribution of our sample is consistent with a Galactic disk age of 8Gyr. A few ultracool WDs may be as old as 12-13Gyr, but our models have problems matching the spectral energy distributions of these objects. There are only two halo WD candidates in our sample. However, trigonometric parallax observations are required for accurate mass and age determinations and to confirm their membership in the halo.
1586. Detailed morphology of SDSS galaxies
ID:
ivo://CDS.VizieR/J/ApJS/186/427
Title:
Detailed morphology of SDSS galaxies
Short Name:
J/ApJS/186/427
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of detailed visual classifications for 14034 galaxies in the Sloan Digital Sky Survey (SDSS) Data Release 4 (DR4, Cat. <II/267>). Our sample includes nearly all spectroscopically targeted galaxies in the redshift range 0.01<z<0.1 down to an apparent extinction-corrected limit of g<16mag. In addition to T-Types, we record the existence of bars, rings, lenses, tails, warps, dust lanes, arm flocculence, and multiplicity. This sample defines a comprehensive local galaxy sample which we will use in future papers to study low-redshift morphology. It will also prove useful for calibrating automated galaxy classification algorithms. In this paper, we describe the classification methodology used, detail the systematics and biases of our sample, and summarize the overall statistical properties of the sample, noting the most obvious trends that are relevant for general comparisons of our catalog with previously published work.
1587. Detected sources at 12{mu}m in 47 Tuc
ID:
ivo://CDS.VizieR/J/A+A/372/85
Title:
Detected sources at 12{mu}m in 47 Tuc
Short Name:
J/A+A/372/85
Date:
21 Oct 2021
Publisher:
CDS
Description:
The present paper investigates the properties of the dust mass loss in stars populating the giant branch of the globular cluster 47 Tuc, by combining ISOCAM and DENIS data. Raster maps of 5 fields covering areas ranging from 4x4 to 15x15arcmin^2^ at different distances from the center of the cluster have been obtained with ISOCAM at 11.5{mu}m (LW10 filter). The covered fields include most of the red variables known in this cluster. A detection threshold of about 0.2 mJy is achieved, allowing us to detect giant stars at 11.5{mu}m all the way down to the horizontal branch. No dust-enshrouded asymptotic giant branch stars have been found in the observed fields, contrary to the situation encountered in LMC/SMC globular clusters with larger turnoff masses. The color index [12]-[2] (based on the ISO 11.5{mu}m flux and on the DENIS K_S_ magnitude) is used as a diagnostic of dust emission (and hence dust mass loss). Its evolution with luminosity along the giant branch reveals that dust mass loss is only present in V3 (the only cluster Mira variable observed in the present study) and in V18, a star presenting intermittent variability. This conclusion confirms the importance of stellar pulsations in the dust formation and ensuing mass loss.
1588. Detection of fast HI outflow in Mrk231
ID:
ivo://CDS.VizieR/J/A+A/593/A30
Title:
Detection of fast HI outflow in Mrk231
Short Name:
J/A+A/593/A30
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the detection, performed with the Westerbork Synthesis Radio Telescope (WSRT) and the Karl Jansky Very Large Array (VLA), of a fast HI 21-cm outflow in the ultra-luminous infrared galaxy Mrk 231. The outflow is observed as shallow HI absorption blueshifted ~1300 km/s with respect to the systemic velocity and located against the inner kpc of the radio source. The outflowing gas has an estimated column density between 5 and 15x10^18^Tspin.cm^-2^. We derive the Tspin to lie in the range 400-2000 K and the corresponding HI densities are n_HI_~10-100cm^-3^. We also obtained deeper continuum images than previously available. They confirm the complex structure of the radio continuum originating both from the AGN and star formation. At the resolution obtained with the VLA (~1-arcsec) we do not see a kpc-scale jet. Instead, we detect a plateau of emission, likely due to star formation, surrounding the bright nuclear region. We also detect a poorly collimated bridge which may represent the channel feeding the southern lobe. The unprecedented depth of the low-resolution WSRT image reveals radio emission extending 50-arcsec (43kpc) to the south and 20arcsec (17kpc) to the north.
1589. Detection of Kepler multiple M-star systems
ID:
ivo://CDS.VizieR/J/ApJ/788/114
Title:
Detection of Kepler multiple M-star systems
Short Name:
J/ApJ/788/114
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have searched the Kepler light curves of ~3900 M-star targets for evidence of periodicities that indicate, by means of the effects of starspots, rapid stellar rotation. Several analysis techniques, including Fourier transforms, inspection of folded light curves, "sonograms", and phase tracking of individual modulation cycles, were applied in order to distinguish the periodicities due to rapid rotation from those due to stellar pulsations, eclipsing binaries, or transiting planets. We find 178 Kepler M-star targets with rotation periods, P_rot_<2 days, and 110 with P_rot_<1 day. Some 30 of the 178 systems exhibit two or more independent short periods within the same Kepler photometric aperture, while several have 3 or more short periods. Adaptive optics imaging and modeling of the Kepler pixel response function for a subset of our sample support the conclusion that the targets with multiple periods are highly likely to be relatively young physical binary, triple, and even quadruple M star systems. We explore in detail the one object with four incommensurate periods all less than 1.2 days, and show that two of the periods arise from one of a close pair of stars, while the other two arise from the second star, which itself is probably a visual binary. If most of these M-star systems with multiple periods turn out to be bound M-stars, this could prove a valuable way discovering young hierarchical M-star systems; the same approach may also be applicable to G and K stars. The ~5% occurrence rate of rapid rotation among the ~3900 M star targets is consistent with spin evolution models that include an initial contraction phase followed by magnetic braking, wherein a typical M star can spend several hundred Myr before spinning down to periods longer than 2 days.
1590. Detection of the secondary eclipse of Qatar-1b
ID:
ivo://CDS.VizieR/J/A+A/595/A61
Title:
Detection of the secondary eclipse of Qatar-1b
Short Name:
J/A+A/595/A61
Date:
21 Oct 2021
Publisher:
CDS
Description:
Qatar-1b is a close-orbiting hot Jupiter (Rp~=1.18R_J_, Mp~=1.33M_J_) around a metal-rich K-dwarf, with orbital separation and period of 0.023AU and 1.42-days. We have observed the secondary eclipse of this exoplanet in the Ks band with the objective of deriving a brightness temperature for the planet and providing further constraints to the orbital configuration of the system. We obtained near-infrared photometric data from the ground by using the OMEGA2000 instrument at the 3.5m telescope at Calar Alto (Spain) in staring mode, with the telescope defocused. We have used principal component analysis (PCA) to identify correlated systematic trends in the data. A Markov chain Monte Carlo analysis was performed to model the correlated systematics and fit for the secondary eclipse of Qatar-1b using a previously developed occultation model. We adopted the prayer bead method to assess the effect of red noise on the derived parameters.