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1031. Compiled photometry for Cham I and II members
ID:
ivo://CDS.VizieR/J/A+A/551/A46
Title:
Compiled photometry for Cham I and II members
Short Name:
J/A+A/551/A46
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a proper motion study aiming at providing further evidence on the origin of the proposed stellar members of the Chamaeleon I and II clouds and to identify interlopers from the foreground young clusters {epsilon} Cha and {eta} Cha. We compiled lists of spectroscopically confirmed members of the four associations, and of background objects in the same line of sight. Using Virtual Observatory tools, we cross-matched these lists with the UCAC3 (Cat. I/315) catalogue to get proper motions for the objects. In the vector point diagram, we identified the different moving groups, and used this information to study the membership of proposed candidate members of the associations from the literature. For those objects with available radial velocities, we computed their Galactic space velocities. We compiled photometry from public data archives and from the literature for the Cha I and II objects. We looked for correlations between the properties of the objects and their proper motions.
1032. Complex cluster Abell 1758 stars
ID:
ivo://CDS.VizieR/J/MNRAS/466/2614
Title:
Complex cluster Abell 1758 stars
Short Name:
J/MNRAS/466/2614
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a weak-lensing and dynamical study of the complex cluster Abell 1758 (A1758, {bar}z=0.278) supported by hydrodynamical simulations. This cluster is composed of two main structures called A1758N and A1758S. The northern structure is composed of A1758NW and A1758NE, with lensing determined masses of 7.90_-1.55_^+1.89^x10^14^M_{sun}_ and 5.49_-1.33_^+1.67^x10^14^M_{sun}_, respectively. They show a remarkable feature: while in A1758NW, there is a spatial agreement among weak-lensing mass distribution, intracluster medium and its brightest cluster galaxy (BCG), in A1758NE, the X-ray peak is located 96_-15_^+14^ arcsec away from the mass peak and BCG positions. Given the detachment between gas and mass, we could use the local surface mass density to estimate an upper limit for the dark matter self-interaction cross-section: {sigma}/m<5.83cm^2^/g. Combining our velocity data with hydrodynamical simulations, we have shown that A1758 NW and NE had their closest approach 0.27Gyr ago and their merger axis is 21+/-12{deg} from the plane of the sky. In the A1758S system, we have measured a total mass of 4.96_-1.19_^+1.08^x10^14^M_{sun}_ and, using radial velocity data, we found that the main merger axis is located at 70+/-4{deg} from the plane of the sky, therefore closest to the line of sight.
1033. CONCH-SHELL catalog of nearby M dwarfs
ID:
ivo://CDS.VizieR/J/MNRAS/443/2561
Title:
CONCH-SHELL catalog of nearby M dwarfs
Short Name:
J/MNRAS/443/2561
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an all-sky catalogue of 2970 nearby (d<~50pc), bright (J<9) M- or late K-type dwarf stars, 86% of which have been confirmed by spectroscopy. This catalogue will be useful for searches for Earth-size and possibly Earth-like planets by future space-based transit missions and ground-based infrared Doppler radial velocity surveys. Stars were selected from the SUPERBLINK proper motion catalogue (Cat. I/298) according to absolute magnitudes, spectra, or a combination of reduced proper motions and photometric colours. From our spectra, we determined gravity-sensitive indices, and identified and removed 0.2% of these as interloping hotter or evolved stars. 13% of the stars exhibit H{alpha} emission, an indication of stellar magnetic activity and possible youth. The mean metallicity is [Fe/H]=-0.07 with a standard deviation of 0.22dex, similar to nearby solar-type stars. We determined stellar effective temperatures by least-squares fitting of spectra to model predictions calibrated by fits to stars with established bolometric temperatures, and estimated radii, luminosities, and masses using empirical relations. 6% of stars with images from integral field spectra are resolved doubles. We inferred the planet population around M dwarfs using Kepler data and applied this to our catalogue to predict detections by future exoplanet surveys.
1034. CoNFIG AGN sample
ID:
ivo://CDS.VizieR/J/MNRAS/430/3086
Title:
CoNFIG AGN sample
Short Name:
J/MNRAS/430/3086
Date:
21 Oct 2021
Publisher:
CDS
Description:
The goal of this work is to determine the nature of the relation between morphology and accretion mode in radio galaxies, including environmental parameters. The CoNFIG extended catalogue (improved by new K_S_-band identifications and estimated redshifts from UKIRT Infrared Deep Sky Survey (UKIDSS), and spectral index measurements from new GMRT observations) is used to select a sub-sample of 206 radio galaxies with z<=0.3 over a wide range of radio luminosity, which are morphology-classified using the Fanaroff-Riley (FR) classification of extended radio sources. For each galaxy, spectroscopic data are retrieved to determine the high/low excitation status of the source, related to its accretion mode. Environmental factors, such as the host galaxy luminosity and a richness factor, are also computed, generally using the Sloan Digital Sky Survey data.
1035. Confirmed members of RX J0152.7-1357
ID:
ivo://CDS.VizieR/J/ApJ/725/1252
Title:
Confirmed members of RX J0152.7-1357
Short Name:
J/ApJ/725/1252
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectrophotometric analysis of galaxies belonging to the dynamically young, massive cluster RX J0152.7-1357 at z~0.84, aimed at understanding the effects of the cluster environment on the star formation history (SFH) of cluster galaxies and the assembly of the red sequence (RS). We use VLT/FORS spectroscopy, ACS/WFC optical, and NTT/SofI near-IR data to characterize SFHs as a function of color, luminosity, morphology, stellar mass, and local environment from a sample of 134 spectroscopic members. In order to increase the signal-to-noise ratio, individual galaxy spectra are stacked according to these properties. Moreover, the D4000, Balmer, CN3883, Fe4383, and C4668 indices are also quantified.
1036. 9380 contact binaries from CRTS VSC
ID:
ivo://CDS.VizieR/J/MNRAS/465/4678
Title:
9380 contact binaries from CRTS VSC
Short Name:
J/MNRAS/465/4678
Date:
21 Oct 2021
Publisher:
CDS
Description:
We construct a sample of 9380 contact binaries (W UMa systems) by using the Catalina Real-Time Transient Survey Variables Sources Catalogue. By measuring brightness change rates, light-curve statistics, and temperatures for this sample, we improve the understanding of contact binary light-curve characteristics, and luminosity variability on decadal time-scales. We show that binaries with convective outer envelopes have a different distribution of light-curve amplitudes and magnitude differences between eclipse minima than binaries with radiative outer envelopes. We find that more than 2000 binaries exhibit a linear change in mean brightness over the 8-yr timespan of observations with at least 3{sigma} significance. We note that 25.9 per cent of binaries with convective outer envelopes exhibit a significant change in brightness, while only 10.5 per cent of radiative binaries exhibit a significant change in brightness. In 205 binaries (2.2 per cent), we find that a sinusoid model better describes the luminosity trend within the 8-yr observation timespan. For these binaries, we report the amplitudes and periods (as estimated using observed half-periods) of this sinusoidal brightness variation and discuss possible mechanisms driving the variation.
1037. Contact binaries in OGLE-I database
ID:
ivo://CDS.VizieR/J/AcA/51/259
Title:
Contact binaries in OGLE-I database
Short Name:
J/AcA/51/259
Date:
21 Oct 2021
Publisher:
CDS
Description:
The present catalog contains the most numerous, observationally homogeneous sample of contact binaries. It is derived from the OGLE experiment (Optical Gravitational Lensing Experiment), in the direction of the Galactic Bulge and the Galactic bar. The observations were made with the 1-m Swope telescope at Las Campanas Observatory in Chile, over the period 1992 to 1995. The present catalog includes the 1575 newly discovered contact binaries fainter than I=18mag as well as the 1165 brighter contact binaries previously published. It also includes a list of 506 objects with nearly sinusoidal light curves, to ease the comparison and/or distinction between contact binaries with the sinusoidal light curves and pulsating stars.
1038. Continuum-band lags in SDSS QSOs from PS1 obs.
ID:
ivo://CDS.VizieR/J/ApJ/836/186
Title:
Continuum-band lags in SDSS QSOs from PS1 obs.
Short Name:
J/ApJ/836/186
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the time lags between the continuum emission of quasars at different wavelengths, based on more than four years of multi-band (g, r, i, z) light curves in the Pan-STARRS Medium Deep Fields. As photons from different bands emerge from different radial ranges in the accretion disk, the lags constrain the sizes of the accretion disks. We select 240 quasars with redshifts of z~1 or z~0.3 that are relatively emission-line free. The light curves are sampled from day to month timescales, which makes it possible to detect lags on the scale of the light crossing time of the accretion disks. With the code JAVELIN, we detect typical lags of several days in the rest frame between the g band and the riz bands. The detected lags are ~2-3 times larger than the light crossing time estimated from the standard thin disk model, consistent with the recently measured lag in NGC 5548 and microlensing measurements of quasars. The lags in our sample are found to increase with increasing luminosity. Furthermore, the increase in lags going from g-r to g-i and then to g-z is slower than predicted in the thin disk model, particularly for high-luminosity quasars. The radial temperature profile in the disk must be different from what is assumed. We also find evidence that the lags decrease with increasing line ratios between ultraviolet Fe II lines and Mg II, which may point to changes in the accretion disk structure at higher metallicity.
1039. Cool carbon stars in the halo and Fornax dSph
ID:
ivo://CDS.VizieR/J/A+A/562/A24
Title:
Cool carbon stars in the halo and Fornax dSph
Short Name:
J/A+A/562/A24
Date:
21 Oct 2021
Publisher:
CDS
Description:
The population of cool carbon (C) stars located far from the galactic plane is probably made of debris of small galaxies such as the Sagittarius dwarf spheroidal galaxy (Sgr), which are disrupted by the gravitational field of the Galaxy. We aim to know this population better through spectroscopy, 2MASS photometric colours, and variability data. When possible, we compared the halo results to C star populations in the Fornax dwarf spheroidal galaxy, Sgr, and the solar neighbourhood. We first present a few new discoveries of C stars in the halo and in Fornax. The number of spectra of halo C stars is now 125. Forty percent show H{alpha} in emission. The narrow location in the JHK diagram of the halo C stars is found to differ from that of similar C stars in the above galaxies. The light curves of the Catalina and LINEAR variability databases were exploited to derive the pulsation periods of 66 halo C stars. A few supplementary periods were obtained with the TAROT telescopes. We confirm that the period distribution of the halo strongly resembles that of Fornax, and we found that it is very different from the C stars in the solar neighbourhood. There is a larger proportion of short-period Mira/SRa variables in the halo than in Sgr, but the survey for C stars in this dwarf galaxy is not complete, and the study of their variability needs to be continued to investigate the link between Sgr and the cool halo C stars.
1040. 86 cool dwarfs observed during K2 Campaigns 1-17
ID:
ivo://CDS.VizieR/J/AJ/158/87
Title:
86 cool dwarfs observed during K2 Campaigns 1-17
Short Name:
J/AJ/158/87
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present revised stellar properties for 172 K2 target stars that were identified as possible hosts of transiting planets during Campaigns 1-17. Using medium-resolution near-infrared spectra acquired with the NASA Infrared Telescope Facility/SpeX and Palomar/TripleSpec, we found that 86 of our targets were bona fide cool dwarfs, 74 were hotter dwarfs, and 12 were giants. Combining our spectroscopic metallicities with Gaia parallaxes and archival photometry, we derived photometric stellar parameters and compared them to our spectroscopic estimates. Although our spectroscopic and photometric radius and temperature estimates are consistent, our photometric mass estimates are systematically {Delta}M_*_=0.11 M_{sun}_ (34%) higher than our spectroscopic mass estimates for the least massive stars (M_*,phot_<0.4 M_{sun}_). Adopting the photometric parameters and comparing our results to parameters reported in the Ecliptic Plane Input Catalog, our revised stellar radii are {Delta}R_*_=0.15 R_{sun}_ (40%) larger, and our revised stellar effective temperatures are roughly {Delta}T_eff_=65 K cooler. Correctly determining the properties of K2 target stars is essential for characterizing any associated planet candidates, estimating the planet search sensitivity, and calculating planet occurrence rates. Even though Gaia parallaxes have increased the power of photometric surveys, spectroscopic characterization remains essential for determining stellar metallicities and investigating correlations between stellar metallicity and planetary properties.