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251. APOSTLE light curve of GJ 1214b
ID:
ivo://CDS.VizieR/J/ApJ/731/123
Title:
APOSTLE light curve of GJ 1214b
Short Name:
J/ApJ/731/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present three transits of GJ 1214b, observed as part of the Apache Point Observatory Survey of Transit Light Curves of Exoplanets (APOSTLE). By applying Markov Chain Monte Carlo techniques to a multi-wavelength data set which included our r-band light curves and previously gathered data of GJ 1214b, we confirm earlier estimates of system parameters. Using spectral energy distribution fitting, mass-luminosity relations, and light curve data, we derived absolute parameters for the star and planet, improving uncertainties by a factor of two for the stellar mass (M_*_=0.153^+0.010^_-0.009_M_{sun}_), stellar radius (R_*_=0.210^+0.005^_-0.004R_{sun}_), planetary radius (R_p_=2.74^+0.06^_-0.05_R_{earth}_), and planetary density ({rho}_p_=1.68+/-0.23g/cm^3^). Transit times derived from our study show no evidence for strong transit timing variations. We also report the detection of two features in our light curves which we believe are evidence for a low-energy stellar flare and a spot-crossing event.
252. APOSTLE r'-band transit lightcurves of TrES-3b
ID:
ivo://CDS.VizieR/J/ApJ/764/8
Title:
APOSTLE r'-band transit lightcurves of TrES-3b
Short Name:
J/ApJ/764/8
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Apache Point Survey of Transit Lightcurves of Exoplanets (APOSTLE) observed 11 transits of TrES-3b over two years in order to constrain system parameters and look for transit timing and depth variations. We describe an updated analysis protocol for APOSTLE data, including the reduction pipeline, transit model, and Markov Chain Monte Carlo analyzer. Our estimates of the system parameters for TrES-3b are consistent with previous estimates to within the 2{sigma} confidence level. We improved the errors (by 10%-30%) on system parameters such as the orbital inclination (i_orb_), impact parameter (b), and stellar density ({rho}_{sstarf}_) compared to previous measurements. The near-grazing nature of the system, and incomplete sampling of some transits, limited our ability to place reliable uncertainties on individual transit depths and hence we do not report strong evidence for variability. Our analysis of the transit timing data shows no evidence for transit timing variations and our timing measurements are able to rule out super-Earth and gas giant companions in low-order mean motion resonance with TrES-3b.
253. APOSTLE transits of XO-2 system
ID:
ivo://CDS.VizieR/J/ApJ/770/36
Title:
APOSTLE transits of XO-2 system
Short Name:
J/ApJ/770/36
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Apache Point Survey of Transit Lightcurves of Exoplanets (APOSTLE) observed 10 transits of XO-2b over a period of 3yr. We present measurements that confirm previous estimates of system parameters like the normalized semi-major axis (a/R_*_), stellar density ({rho}_*_), impact parameter (b), and orbital inclination (i_orb_). Our errors on system parameters like a/R_*_ and {rho}_*_ have improved by ~40% compared to previous best ground-based measurements. Our study of the transit times show no evidence for transit timing variations (TTVs) and we are able to rule out co-planar companions with masses >=0.20M_{Earth}_ in low order mean motion resonance with XO-2b. We also explored the stability of the XO-2 system given various orbital configurations of a hypothetical planet near the 2:1 mean motion resonance. We find that a wide range of orbits (including Earth-mass perturbers) are both dynamically stable and produce observable TTVs. We find that up to 51% of our stable simulations show TTVs that are smaller than the typical transit timing errors (~20s) measured for XO-2b, and hence remain undetectable.
254. A preliminary 20pc census from the NLTT catalogue
ID:
ivo://CDS.VizieR/J/AJ/128/463
Title:
A preliminary 20pc census from the NLTT catalogue
Short Name:
J/AJ/128/463
Date:
21 Oct 2021
Publisher:
CDS
Description:
Continuing our census of late-type dwarfs in the solar neighborhood, we present BVRI photometry and optical spectroscopy of 800 mid-type M dwarfs drawn from the NLTT proper-motion catalog. The targets are taken both from our own cross-referencing of the NLTT Catalogue and the 2MASS Second Incremental Data Release, and from the revised NLTT compiled recently by Salim & Gould (Cat. <J/ApJ/582/1011>). All are identified as nearby-star candidates based on their location in the (m_r_, m_r_-K_s_) diagram. Three hundred stars discussed here have previous astrometric, photometric, or spectroscopic observations. We present new BVRI photometry for 101 stars, together with low-resolution spectroscopy of a further 400 dwarfs.
255. APS Catalog of Galaxies behind Virgo
ID:
ivo://CDS.VizieR/J/ApJ/473/822
Title:
APS Catalog of Galaxies behind Virgo
Short Name:
J/ApJ/473/822
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 1268 galaxies, essentially complete to B<=17.0, found by scanning glass copies of several fields of the original Palomar Sky Survey using the Minnesota Automated Plate Scanner in its isodensitometric mode (as opposed to the threshold densitometric mode used in the APS Catalog of the POSS I). In addition to the different scanning mode, we have employed a different star-galaxy separation method and have visually inspected POSS prints to verify that each image remaining in the catalog is non-stellar. The scanned fields are distributed generally in two areas, one around the outskirts of the Virgo Cluster, the other toward the antipode of the cluster (but still in the northern celestial hemisphere). The catalog gives the position of the center of each galaxy; estimates of the blue and red magnitudes within the outermost threshold crossing and of the blue magnitude extrapolated to zero surface brightness; blue and red diameters of four ellipses fit to the four threshold crossings (approximately 23.8, 23.6, 23.2, and 22.7 mag per square arcsec in blue, and 22.5, 22.4, 21.5 and 21.2 mag per square arcsec in red), and the ellipticities of those four ellipses. The catalog has served as a base from which to draw targets for a Tully-Fisher study of the Virgocentric infall velocity of the Local Group.
256. APS Galaxies in the North Galactic Pole
ID:
ivo://CDS.VizieR/VII/214
Title:
APS Galaxies in the North Galactic Pole
Short Name:
VII/214
Date:
21 Oct 2021
Publisher:
CDS
Description:
(of PhD Thesis, from Minessota) I am using the Minnesota Automated Plate Scanner (APS) to construct two galaxy catalogs. The Minnesota Automated Plate Scanner Pisces-Perseus Survey (MAPS-PP) is used to search for modern-day remnant signatures of large-scale structure formation processes, specifically, galaxy alignments relative to surrounding large-scale structure. Weak evidence for such alignments is found, although the type of alignments seen don't strongly support any one large-scale structure formation model. Comparison of the MAPS-PP to pre-existing galaxy catalogs has led to the discovery that the Uppsala General Catalog and Third Reference Catalog of Galaxies exhibit a very strong measurement bias: their diameters are measured to different isophotes at different galaxy inclinations. Therefore previous determinations of the diameter function and the internal extinction properties of other galaxies (most of which have relied on one of these two galaxy catalogs) have suffered from a biased diameter measurement. I avoid this bias by using the APS data (which is obtained using automated computer-based criteria for measuring the structural properties of images digitized from photographic plates) to construct a catalog of over 200,000 galaxies within 30 degrees of the North Galactic Pole (the MAPS-NGP). The MAPS-NGP is the deepest galaxy catalog constructed over such a large area of the sky and used to re-evaluate previous investigations of the internal extinction in galaxies.
257. Apsidal motions of 90 SMC eccentric binaries
ID:
ivo://CDS.VizieR/J/MNRAS/460/650
Title:
Apsidal motions of 90 SMC eccentric binaries
Short Name:
J/MNRAS/460/650
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examined light curves of 1138 stars brighter than 18.0mag in the I band and less than a mean magnitude error of 0.1mag in the V band from the Optical Gravitational Lensing Experiment (OGLE)-III eclipsing binary catalogue, and found 90 new binary systems exhibiting apsidal motion. In this study, the samples of apsidal motion stars in the Small Magellanic Cloud (SMC) were increased by a factor of about 3.0 than previously known. In order to determine the period of the apsidal motion for the binaries, we analysed in detail both the light curves and eclipse timings using the MACHO (MAssive Compact Halo Objects) and OGLE photometric data base. For the eclipse timing diagrams of the systems, new times of minimum light were derived from the full light curve combined at intervals of one year from the survey data. The new 90 binaries have apsidal motion periods in the range of 12-897yr. An additional short-term oscillation was detected in four systems (OGLE-SMC-ECL-1634, 1947, 3035, and 4946), which most likely arises from the existence of a third body orbiting each eclipsing binary. Since the systems presented here are based on homogeneous data and have been analysed in the same way, they are suitable for further statistical analysis.
258. AQ Boo VRI differential light curves
ID:
ivo://CDS.VizieR/J/other/NewA/48.42
Title:
AQ Boo VRI differential light curves
Short Name:
J/other/NewA/48.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We obtained the first VRI CCD light curves of the short-period contact eclipsing binary AQ Boo, which was observed on March 22 and April 19 in 2014 at Xinglong station of National Astronomical Observatories, and on January 20, 21 and February 28 in 2015 at Kunming station of Yunnan Observatories of Chinese Academy of Sciences, China. Using our six newly obtained minima and the minima that other authors obtained previously, we revised the ephemeris of AQ Boo. By fitting the O-C (observed minus calculated) values of the minima, the orbital period of AQ Boo shows a decreasing tendency dP/dt=-1.47(0.17)x10^-17^day/year. We interpret the phenomenon by mass transfer from the secondary (more massive) component to the primary (less massive) one. By using the updated Wilson & Devinney (1971ApJ...166..605W) program, we also derived the photometric orbital parameters of AQ Boo for the first time. We conclude that AQ Boo is a near contact binary with a low contact factor of 14.43%, and will become an over-contact system as the mass transfer continues.
259. Aquarius superclusters. I.
ID:
ivo://CDS.VizieR/J/AJ/123/1200
Title:
Aquarius superclusters. I.
Short Name:
J/AJ/123/1200
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the distribution of galaxies and galaxy clusters in a 10{deg}x6{deg} field in the Aquarius region. In addition to 63 clusters in the literature, we have found 39 new candidate clusters using a matched-filter technique and a counts-in-cells analysis. From redshift measurements of galaxies in the direction of these cluster candidates, we present new mean redshifts for 31 previously unobserved clusters, while improved mean redshifts are presented for 35 other systems.
260. Aquarius superclusters. II.
ID:
ivo://CDS.VizieR/J/AJ/128/2642
Title:
Aquarius superclusters. II.
Short Name:
J/AJ/128/2642
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present spectroscopic and photometric data for 920 galaxies selected in 68 fields of the Aquarius Cluster Catalog. Typically, the 15 brightest candidate members with magnitudes in the range 16<b_J_<21 were selected for observations, and ~71% turn out to be cluster members. Using the new redshift determinations, we assign galaxies to groups and clusters, and by including data from the literature we calculate systemic velocities and velocity dispersions for 74 clusters, each with redshifts measured for at least six individual galaxies.