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51. The SkyMapper DR3 SSOs
ID:
ivo://CDS.VizieR/J/A+A/658/A109
Title:
The SkyMapper DR3 SSOs
Short Name:
J/A+A/658/A109
Date:
22 Feb 2022
Publisher:
CDS
Description:
The populations of small bodies of the Solar System (asteroids, comets, and Kuiper Belt objects) are used to constrain the origin and evolution of the Solar System. Their orbital distribution and composition distribution are both required to track the dynamical pathway from their formation regions to their current locations. We aim to increase the sample of Solar System objects (SSOs) that have multifilter photometry and compositional taxonomy. Methods. We searched for moving objects in the SkyMapper Southern Survey. We used the predicted SSO positions to extract photometry and astrometry from the SkyMapper frames. We then applied a suite of filters to clean the catalog from false-positive detections. We finally used the near-simultaneous photometry to assign a taxonomic class to objects. We release a catalog of 880,528 individual observations, consisting of 205515 known and unique SSOs. The catalog completeness is estimated to be about 97% down to V=18mag and the purity is higher than 95% for known SSOs. The near-simultaneous photometry provides either three, two, or a single color that we use to classify 117356 SSOs with a scheme consistent with the widely used Bus-DeMeo taxonomy. The present catalog contributes significantly to the sample of asteroids with known surface properties (about 40% of main-belt asteroids down to an absolute magnitude of 16). We will release more observations of SSOs with future SkyMapper data releases.
52. Time of minima of HD 181068
ID:
ivo://CDS.VizieR/J/MNRAS/428/1656
Title:
Time of minima of HD 181068
Short Name:
J/MNRAS/428/1656
Date:
21 Oct 2021
Publisher:
CDS
Description:
HD 181068 is the brighter of the two known triply eclipsing hierarchical triple stars in the Kepler field. It has been continuously observed for more than 2yr with the Kepler space telescope. Of the nine quarters of the data, three have been obtained in short-cadence mode, that is one point per 58.9s. Here we analyse this unique data set to determine absolute physical parameters (most importantly the masses and radii) and full orbital configuration using a sophisticated novel approach. We measure eclipse timing variations (ETVs), which are then combined with the single-lined radial velocity measurements to yield masses in a manner equivalent to double-lined spectroscopic binaries. We have also developed a new light-curve synthesis code that is used to model the triple, mutual eclipses and the effects of the changing tidal field on the stellar surface and the relativistic Doppler beaming. By combining the stellar masses from the ETV study with the simultaneous light-curve analysis we determine the absolute radii of the three stars. Our results indicate that the close and the wide subsystems revolve in almost exactly coplanar and prograde orbits. The newly determined parameters draw a consistent picture of the system with such details that have been beyond reach before.
53. Times of maxima for 23 delta Scuti stars
ID:
ivo://CDS.VizieR/J/PASP/133/H4201
Title:
Times of maxima for 23 delta Scuti stars
Short Name:
J/PASP/133/H4201
Date:
17 Jan 2022 00:25:09
Publisher:
CDS
Description:
The multi-color CCD photometric study of 27 delta Scuti stars is presented. By using approximately three years of photometric observations, we obtained the times of maxima and magnitude changes during the observation time interval for each star. The ephemeris of our delta Scuti star was calculated based on the Markov Chain Monte Carlo (MCMC) method using the observed times of maxima and the period of star' oscillations. We used the Gaia EDR3 parallaxes to calculate the luminosities and also the absolute magnitudes of these delta Scuti stars. The fundamental physical parameters of all studied stars, such as mass and radius, were estimated. We determined the pulsation modes of the stars based on the pulsation constants. Moreover, the period-luminosity relation of delta Scuti stars was investigated and discussed. Then, by using a machine learning classification, new P-L relations for fundamental and overtone modes are presented.
54. Times of minima for 1SWASP J234401.81-212229.1
ID:
ivo://CDS.VizieR/J/A+A/558/A71
Title:
Times of minima for 1SWASP J234401.81-212229.1
Short Name:
J/A+A/558/A71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report our investigation of 1SWASP J234401.81-212229.1, a variable with a 18461.6s period. After identification in a 2011 search of the SuperWASP archive for main-sequence eclipsing binary candidates near the distribution's short-period limit of ~0.20d, it was measured to be undergoing rapid period decrease in our earlier work, though later observations supported a cyclic variation in period length. Spectroscopic data obtained in 2012 with the Southern African Large Telescope did not, however, support the interpretation of the object as a normal eclipsing binary. Here, we consider three possible explanations consistent with the data: a single-star oblique rotator model in which variability results from stable cool spots on opposite magnetic poles; a two-star model in which the secondary is a brown dwarf; and a three-star model involving a low-mass eclipsing binary in a hierarchical triple system. We conclude that the latter is the most likely model.
55. Transiting planets in Kepler-47 circumbinary system
ID:
ivo://CDS.VizieR/J/AJ/157/174
Title:
Transiting planets in Kepler-47 circumbinary system
Short Name:
J/AJ/157/174
Date:
21 Oct 2021
Publisher:
CDS
Description:
Of the nine confirmed transiting circumbinary planet systems, only Kepler-47 is known to contain more than one planet. Kepler-47 b (the "inner planet") has an orbital period of 49.5 days and a radius of about 3 R_{Earth}_. Kepler-47 c (the "outer planet") has an orbital period of 303.2 days and a radius of about 4.7 R_{Earth}_. Here we report the discovery of a third planet, Kepler-47 d (the "middle planet"), which has an orbital period of 187.4 days and a radius of about 7 R_{Earth}_. The presence of the middle planet allows us to place much better constraints on the masses of all three planets, where the 1{sigma} ranges are less than 26 M_{Earth}_, between 7-43 M_{Earth}_, and between 2-5 M_{Earth}_ for the inner, middle, and outer planets, respectively. The middle and outer planets have low bulk densities, with {rho}_middle_<0.68 g/cm^3^ and {rho}_outer_<0.26 g/cm^3^ at the 1{sigma} level. The two outer planets are "tightly packed", assuming the nominal masses, meaning no other planet could stably orbit between them. All of the orbits have low eccentricities and are nearly coplanar, disfavoring violent scattering scenarios and suggesting gentle migration in the protoplanetary disk.
56. Transit times and durations of three KOIs
ID:
ivo://CDS.VizieR/J/ApJ/790/31
Title:
Transit times and durations of three KOIs
Short Name:
J/ApJ/790/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
KOI-227, KOI-319 and KOI-884 are identified here as (at least) two planet systems. For KOI-319 and KOI-884, the observed Transit Timing Variations (TTVs) of the inner transiting planet are used to detect an outer non-transiting planet. The outer planet in KOI-884 is =~2.6 Jupiter masses and has the orbital period just narrow of the 3:1 resonance with the inner planet (orbital period ratio 2.93). The distribution of parameters inferred from KOI-319.01's TTVs is bimodal with either a =~1.6 Neptune-mass (M_N_) planet wide of the 5:3 resonance (period 80.1 days) or a =~1 Saturn-mass planet wide of the 7:3 resonance (period 109.2 days). The radial velocity measurements can be used in this case to determine which of these parameter modes is correct. KOI-227.01's TTVs with large =~10 hr amplitude can be obtained for planetary-mass companions in various major resonances. Based on the Bayesian evidence, the current TTV data favor the outer 2:1 resonance with a companion mass =~1.5 M_N_, but this solution implies a very large density of KOI-227.01. The inner and outer 3:2 resonance solutions with sub-Neptune-mass companions are physically more plausible, but will need to be verified.
57. Transit times for Kepler-79's known planets
ID:
ivo://CDS.VizieR/J/ApJ/785/15
Title:
Transit times for Kepler-79's known planets
Short Name:
J/ApJ/785/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
Kepler-79 (KOI-152) has four planetary candidates ranging in size from 3.5 to 7 times the size of the Earth, in a compact configuration with orbital periods near a 1:2:4:6 chain of commensurability, from 13.5 to 81.1 days. All four planets exhibit transit timing variations with periods that are consistent with the distance of each planet to resonance with its neighbors. We perform a dynamical analysis of the system based on transit timing measurements over 1282 days of Kepler photometry. Stellar parameters are obtained using a combination of spectral classification and the stellar density constraints provided by light curve analysis and orbital eccentricity solutions from our dynamical study. Our models provide tight bounds on the masses of all four transiting bodies, demonstrating that they are planets and that they orbit the same star. All four of Kepler-79's transiting planets have low densities given their sizes, which is consistent with other studies of compact multiplanet transiting systems. The largest of the four, Kepler-79 d (KOI-152.01), has the lowest bulk density yet determined among sub-Saturn mass planets.
58. TYC 3700-1384-1, V1511 Her, V1179 Her minima
ID:
ivo://CDS.VizieR/J/MNRAS/501/4935
Title:
TYC 3700-1384-1, V1511 Her, V1179 Her minima
Short Name:
J/MNRAS/501/4935
Date:
21 Oct 2021
Publisher:
CDS
Description:
The first multi-colour light curve models and period studies for the totally eclipsing W UMa stars TYC 3700-1384-1, V1511 Her and V1179 Her are presented. All three stars are A-subtype W UMa stars of spectral type F. The light curve solutions show that TYC 3700-1384-1 has a moderately low mass ratio of q=0.182+/-0.001 and a degree of overcontact of f=49%. For V1179 Her a mass ratio q=0.153+/-0.001 and a degree of overcontact of f=48% is derived. The solution for V1511 Her is inconclusive, however the mass ratio is expected to be between 0.13<q<0.15. The evolutionary status is compared with zero-age main sequence stars taking into account energy transfer from the primary to the secondary component. The primary component of TYC 3700-1384-1 fits well in the main-sequence, while V1179 Her is more evolved. The period study reveals for all three stars a continuously increasing period at a rate of dP/dt=6.1x10^-7^d/yr, dP/dt=5.0x10^-7^d/yr and dP/dt=9.6x10^-7^d/yr for TYC 3700-1384-1, V1511 Her and V1179 Her respectively. The estimated mass transfer rates derived from these period changes are 1.6x10^-7^M_{sun}_/yr for TYC 3700-1384-1 and 1.9x10^-7^M_{sun}_/yr for V1179 Her.
59. TZ Boo & Y Sex orbital periods
ID:
ivo://CDS.VizieR/J/A+A/355/171
Title:
TZ Boo & Y Sex orbital periods
Short Name:
J/A+A/355/171
Date:
21 Oct 2021
Publisher:
CDS
Description:
TZ Boo and Y Sex are two A-type contact binaries. At the set, times of light minimum of the two stars were collected.
60. UT1 definitions in IAU 2000
ID:
ivo://CDS.VizieR/J/A+A/406/1135
Title:
UT1 definitions in IAU 2000
Short Name:
J/A+A/406/1135
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper provides expressions to be used to implement the new definition of UT1 corresponding to the IAU 2000 resolutions either in the new (CEO-based) or classical (equinox-based) transformations between the International Terrestrial Reference System (ITRS) and the Geocentric Celestial Reference System (GCRS). The new expression for Greenwich Sidereal Time (GST) has to be in agreement at the micro-arcsecond level, for one century, with the IAU 2000 expressions for the Earth Rotation Angle (ERA) and for the quantity s positioning the Celestial Ephemeris Origin (CEO) on the equator of the CIP. The computations of the new expressions using the IAU 2000 precession-nutation model are performed in such a manner as to ensure that there is no discontinuity in UT1 on 1 January 2003 and that there is equivalence of the classical and new transformations between the ITRS and GCRS relative to the rotation about the axis of the CIP when these expressions are used. The equinox offset that is considered in the computations refers to the dynamical mean equinox of J2000.0. The resulting expressions have been included in the IERS Conventions 2000.