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2851. Three binary systems in the Large Magellanic Cloud
ID:
ivo://CDS.VizieR/J/AJ/158/185
Title:
Three binary systems in the Large Magellanic Cloud
Short Name:
J/AJ/158/185
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the physical properties and apsidal motion elements of three eccentric eclipsing binaries in the Large Magellanic Cloud. The time-series photometric observations were carried out for a total of 41 nights between 2018 November and 2019 February using the KMTNet 1.6 m telescopes installed in South Africa and Australia. The radial velocities of binary components were measured using about 15 spectra per system collected from the ESO Science Archive Facility, which were observed with the Very Large Telescope 8.2 m telescope. The effective temperatures of the more massive binary components were determined to be 19000+/-500 K for OGLE-LMC-ECL-05797, 17000+/-500 K for OGLE-LMC-ECL-05861, and 19000+/-500 K for OGLE-LMC-ECL-06510 by comparing the observed spectra and the stellar atmosphere models obtained from the BOSZ spectral library. The absolute dimensions of each system were derived by analyzing the radial velocity curves together with the light curves obtained from the KMTNet, OGLE, and MACHO observations during about three decades. For the apsidal motion study, new eclipse timings were derived from the KMTNet and survey photometry. The apsidal motion elements of the three binaries were determined from both light curve and eclipse timing analysis. The periods of apsidal motion were 67+/-2 yr for OGLE-LMC-ECL-05797, 124+/-6 yr for OGLE-LMC-ECL-05861, and 39+/-1 yr for OGLE-LMC-ECL-06510 and their internal structure constants (ISCs) were log k_2,obs_=-2.3+/-0.1, -2.4+/-0.1, and -2.1+/-0.1 in the same order. The observed ISCs of OGLE-LMC-ECL-05797 and OGLE-LMC-ECL-05861 showed a good match to the theoretical ISC values, while the value of OGLE- LMC-ECL-06510 was somewhat larger than the theoretical one.
2852. Three short-period eclipsing binaries BVRI photometry
ID:
ivo://CDS.VizieR/J/AJ/154/260
Title:
Three short-period eclipsing binaries BVRI photometry
Short Name:
J/AJ/154/260
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, we present new BVRI light curves of short-period contact eclipsing binaries V1101 Her and AD Phe from our observations carried out from 2014 to 2015 using the SARA KP and SARA CT telescopes. There is an eclipsing binary located at {alpha}(2000)=01h16m36.15s and {delta}(2000)=-39{deg}49'55.7" in the field of view of AD Phe. We derived an updated ephemeris and found there a cyclic variation overlaying a continuous period increase (V1101 Her) and decrease (AD Phe). This kind of cyclic variation may be attributed to the light time effect via the presence of the third body or magnetic activity cycle. The orbital period increase suggests that V1101 Her is undergoing a mass-transfer from the primary to the secondary component (dM_1_/dt=2.64(+/-0.11)x10^-6^ M_{sun}_/yr) with the third body (P3=13.9(+/-1.9) years), or 2.81(+/-0.07)x10^-6^ M_{sun}_/yr for an increase and magnetic cycle (12.4(+/-0.5) years). The long-term period decrease suggests that AD Phe is undergoing a mass-transfer from the secondary component to the primary component at a rate of -8.04(+/-0.09)x10^-8^ M_{sun}_/yr for a period decrease and the third body (P3=56.2(+/-0.8) years), or -7.11(+/-0.04)x10^-8^ M_{sun}_/yr for a decrease and magnetic cycle (50.3(+/-0.5) years). We determined their orbital and geometrical parameters. For AD Phe, we simultaneously analyzed our BVRI light curves and the spectroscopic observations obtained by Duerbeck & Rucinski (2007AJ....133..169D). The spectral type of V1101 Her was classified as G0+/-2V by LAMOST stellar spectra survey. The asymmetry of the R-band light curve of AD Phe obtained by McFarlane & Hilditch in 1987 (1987MNRAS.227..381M) is explained by a cool spot on the primary component.
2853. THYME. V. Discovering a new stellar association
ID:
ivo://CDS.VizieR/J/AJ/161/171
Title:
THYME. V. Discovering a new stellar association
Short Name:
J/AJ/161/171
Date:
08 Mar 2022
Publisher:
CDS
Description:
The detection and characterization of young planetary systems offer a direct path to study the processes that shape planet evolution. We report on the discovery of a sub-Neptune-sized planet orbiting the young star HD110082 (TOI-1098). Transit events we initially detected during TESS Cycle 1 are validated with time-series photometry from Spitzer. High-contrast imaging and high-resolution, optical spectra are also obtained to characterize the stellar host and confirm the planetary nature of the transits. The host star is a late-F dwarf (M*=1.2M{sun}) with a low-mass, M dwarf binary companion (M*=0.26M{sun}) separated by nearly one arcminute (~6200au). Based on its rapid rotation and Lithium absorption, HD110082 is young, but is not a member of any known group of young stars (despite proximity to the Octans association). To measure the age of the system, we search for coeval, phase-space neighbors and compile a sample of candidate siblings to compare with the empirical sequences of young clusters and to apply quantitative age-dating techniques. In doing so, we find that HD110082 resides in a new young stellar association we designate MELANGE-1, with an age of 250_-70_^+50^Myr. Jointly modeling the TESS and Spitzer light curves, we measure a planetary orbital period of 10.1827days and radius of Rp=3.2{+/-}0.1R{Earth}. HD110082b's radius falls in the largest 12% of field-age systems with similar host-star mass and orbital period. This finding supports previous studies indicating that young planets have larger radii than their field-age counterparts.
2854. Tidal features from RESOLVE survey & DECaLS images
ID:
ivo://CDS.VizieR/J/ApJ/857/144
Title:
Tidal features from RESOLVE survey & DECaLS images
Short Name:
J/ApJ/857/144
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study tidal features around galaxies in the REsolved Spectroscopy Of a Local VolumE (RESOLVE) survey. Our sample consists of 1048 RESOLVE galaxies that overlap with the DECam Legacy Survey, which reaches an r-band 3{sigma} depth of ~27.9mag/arcsec^2^ for a 100arcsec^2^ feature. Images were masked, smoothed, and inspected for tidal features such as streams, shells, or tails/arms. We find tidal features in 17+/-2% of our galaxies, setting a lower limit on the true frequency. The frequency of tidal features in the gas-poor (gas-to-stellar mass ratio <0.1) subsample is lower than in the gas-rich subsample (13+/-3% versus 19+/-2%). Within the gas-poor subsample, galaxies with tidal features have higher stellar and halo masses, ~3x closer distances to nearest neighbors (in the same group), and possibly fewer group members at fixed halo mass than galaxies without tidal features, but similar specific star formation rates. These results suggest tidal features in gas-poor galaxies are typically streams/shells from dry mergers or satellite disruption. In contrast, the presence of tidal features around gas-rich galaxies does not correlate with stellar or halo mass, suggesting these tidal features are often tails/arms from resonant interactions. Similar to tidal features in gas-poor galaxies, tidal features in gas-rich galaxies imply 1.7x closer nearest neighbors in the same group; however, they are associated with diskier morphologies, higher star formation rates, and higher gas content. In addition to interactions with known neighbors, we suggest that tidal features in gas-rich galaxies may arise from accretion of cosmic gas and/or gas-rich satellites below the survey limit.
2855. Times & durations in Kepler-80 planetary system
ID:
ivo://CDS.VizieR/J/AJ/162/114
Title:
Times & durations in Kepler-80 planetary system
Short Name:
J/AJ/162/114
Date:
16 Mar 2022 00:10:21
Publisher:
CDS
Description:
Since the launch of the Kepler space telescope in 2009 and the subsequent K2 mission, hundreds of multiplanet systems have been discovered. The study of such systems, both as individual systems and as a population, leads to a better understanding of planetary formation and evolution. Kepler-80, a K dwarf hosting six super-Earths, was the first system known to have four planets in a chain of resonances, a repeated geometric configuration. Transiting planets in resonant chains can enable us to estimate not only the planets' orbits and sizes but also their masses. Since the original resonance analysis and TTV fitting of Kepler-80, a new planet has been discovered whose signal likely altered the measured masses of the other planets. Here, we determine masses and orbits for all six planets hosted by Kepler-80 by direct forward photodynamical modeling of the light curve of this system. We then explore the resonant behavior of the system. We find that the four middle planets are in a resonant chain, but that the outermost planet only dynamically interacts in ~14% of our solutions. We also find that the system and its dynamic behavior are consistent with in situ formation and compare our results to two other resonant chain systems, Kepler-60 and TRAPPIST-1.
2856. Times of minima for 21 early-type SMC eccentric EBs
ID:
ivo://CDS.VizieR/J/AJ/157/87
Title:
Times of minima for 21 early-type SMC eccentric EBs
Short Name:
J/AJ/157/87
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the apsidal motion and light-curve analyses of 21 eccentric eclipsing binaries located in the Small Magellanic Cloud. Most of these systems have never been studied before, hence their orbital and physical properties as well as the apsidal motion parameters are given here for the first time. All the systems are of early spectral type, having orbital periods up to 4 days. The apsidal motion periods were derived to be from 7.2 to 200 yr (OGLE-SMC-ECL-2194 having the shortest apsidal period among known main-sequence systems). The orbital eccentricities are usually rather mild (median of about 0.06), the maximum eccentricity being 0.33. For the period analysis using O-C diagrams of eclipse timings, in total 951 minima were derived from survey photometry as well as our new data. Moreover, six systems show some additional variation in their O-C diagrams, which should indicate the presence of hidden additional components in them. According to our analysis these third-body variations have periods from 6.9 to 22 yr.
2857. 2007.5 to 2010.4 HST astrometry of HD 202206
ID:
ivo://CDS.VizieR/J/AJ/153/258
Title:
2007.5 to 2010.4 HST astrometry of HD 202206
Short Name:
J/AJ/153/258
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using Hubble Space Telescope Fine Guidance Sensor astrometry and previously published radial velocity measures, we explore the exoplanetary system HD202206. Our modeling results in a parallax, {pi}_abs_=21.96+/-0.12 milliseconds of arc, a mass for HD202206B of M_B_=0.089_-0.006_^+0.007M_{Sun}_, and a mass for HD202206c of M_c_=17.9_-1.8_^+2.9^M_Jup_. HD202206 is a nearly face-on G + M binary orbited by a brown dwarf. The system architecture that we determine supports past assertions that stability requires a 5:1 mean motion resonance (we find a period ratio, P_c_/P_B_=4.92+/-0.04) and coplanarity (we find a mutual inclination, {Phi}=6{deg}+/-2{deg}).
2858. Toulouse AC Zone Data Reduced to ACRS
ID:
ivo://CDS.VizieR/I/232
Title:
Toulouse AC Zone Data Reduced to ACRS
Short Name:
I/232
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Toulouse Zone, whose plates are centered between declinations +5 and +11 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of almost 270,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
2859. Tracing stars of MW dwarf galaxies: Sextans
ID:
ivo://CDS.VizieR/J/A+A/609/A53
Title:
Tracing stars of MW dwarf galaxies: Sextans
Short Name:
J/A+A/609/A53
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a deep and very spatially extended CTIO/DECam g and r photometric catalogue of point-sources (reaching out to ~2 magnitudes below the oldest main-sequence turn-off and covering ~20deg^2^) around the Sextans dwarf spheroidal galaxy, together with another catalogue of literature spectroscopic measurements (Walker et al., 2009, Cat. J/AJ/137/3100 and Battaglia et al., 2011, Cat. J/MNRAS/411/1013) with updated membership probabilities.
2860. 4 transiting F-M binary systems
ID:
ivo://CDS.VizieR/J/MNRAS/437/2831
Title:
4 transiting F-M binary systems
Short Name:
J/MNRAS/437/2831
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of four transiting F-M binary systems with companions between 0.1 and 0.2M_{sun}_ in mass by the HATSouth survey. These systems have been characterized via a global analysis of the HATSouth discovery data, combined with high-resolution radial velocities and accurate transit photometry observations. We determined the masses and radii of the component stars using a combination of two methods: isochrone fitting of spectroscopic primary star parameters and equating spectroscopic primary star rotation velocity with spin-orbit synchronization. These new very low mass companions are HATS550-016B (0.110_-0.006_^+0.005^M_{sun}_, 0.147_-0.004_^+0.003^R_{sun}_), HATS551-019B (0.17_-0.01_^+0.01^M_sun}_, 0.18_-0.01_^+0.01^R_{sun}_), HATS551-021B (0.132_-0.005_^+0.014^M_sun}_, 0.154_-0.008_^+0.006^R_{sun}_) and HATS553-001B (0.20_-0.02_^+0.01^M_sun}_, 0.22_-0.01_^+0.01^R_{sun}_). We examine our sample in the context of the radius anomaly for fully convective low-mass stars. Combining our sample with the 13 other well-studied very low mass stars, we find a tentative 5 percent systematic deviation between the measured radii and theoretical isochrone models.