- ID:
- ivo://CDS.VizieR/J/ApJ/742/116
- Title:
- Photometry of four massive transiting exoplanets
- Short Name:
- J/ApJ/742/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of four relatively massive (2-7M_J_) transiting extrasolar planets. HAT-P-20b orbits the moderately bright V=11.339 K3 dwarf star GSC 1910-00239 on a circular orbit, with a period P=2.875317+/-0.000004 days. The planetary companion has a mass of 7.246+/-0.187M_J_ and a radius of 0.867+/-0.033R_J_ yielding a mean density of 13.78+/-1.50g/cm^3^. HAT-P-21b orbits the V=11.685 G3 dwarf star GSC 3013-01229 on an eccentric (e=0.228+/-0.016) orbit, with a period P=4.124481+/-0.000007 days. The planetary companion has a mass of 4.063+/-0.161M_J_ and a radius of 1.024+/-0.092R_J_ yielding a mean density of 4.68^+1.59^_-0.99_g/cm^3^. HAT-P-21b is a borderline object between the pM and pL class planets, and the transits occur near apastron. HAT-P-22b orbits the bright V=9.732 G5 dwarf star HD 233731 on a circular orbit, with a period P=3.212220+/-0.000009 days. The planet has a mass of 2.147+/-0.061M_J_ and a compact radius of 1.080+/-0.058R_J_ yielding a mean density of 2.11^+0.40^_-0.29_g/cm^3^. The host star also harbors an M-dwarf companion at a wide separation. Finally, HAT-P-23b orbits the V=12.432 G0 dwarf star GSC 1632-01396 on a close to circular orbit, with a period P=1.212884+/-0.000002 days. The planetary companion has a mass of 2.090+/-0.111M_J_ and a radius of 1.368+/-0.090R_J_ yielding a mean density of 1.01+/-0.18g/cm^3^. HAT-P-23b is an inflated and massive hot Jupiter on a very short period orbit, and has one of the shortest characteristic infall times (7.5^+2.9^_-1.8_Myr) before it gets engulfed by the star.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/628/A108
- Title:
- Photometry of Kepler-82b and c transits
- Short Name:
- J/A+A/628/A108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- From the Kepler mission four planets were detected and confirmed in the Kepler-82 system. The two inner ones (d and e) show no transit timing variations (TTVs) and are dynamically independent from the two outer ones (b and c), which are showing TTVs. A dynamical analysis of the Kepler-82b/c system delivered a very high, hardly to explain, density ratio of about ten between the planets. A chopping component in the TTVs of the outer planet (Kepler-82b) is not explained by the two-planet model. This chopping component hints on another outer planet near the 3:2 or 3:1 resonance to planet c. The time span of Kepler observations are too short for distinguishing between the two models, the dynamical cycle is not fully covered. The completion of the dynamical cycle of this and other Kepler Objects of Interest (KOIs) showing TTVs is the aim of the KOINet. Within the network follow-up observations with ground-based telescopes are organized. These follow-up observations of Kepler-82b/c transits helped to distinguish between the two models, resulting is the detection of a new planet near the 3:2 resonance to Kepler-82d in the system. A detailed photodynamical modelling of the system was carried out to fully characterise the system parameters. The inclusion of the new planet also lead to a more reasonable density ratio of planet b to c of about two.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A41
- Title:
- Photometry of Kepler-9b and c transits
- Short Name:
- J/A+A/618/A41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Kepler-9b/c system is a prime example of anti-correlated transit timing variations (TTVs). These TTVs results from the dynamical interaction amplified by the near 2:1 period resonance of the planets. The dynamical cycle was only almost finished when the Kepler telescope stopped the observations on that field. To complement the dynamical cycle of this and other Kepler Objects of Interest (KOIs) showing TTVs, the KOINet was build to organize follow-up observations with ground-based telescopes. These follow-up observations of Kepler-9b/c transits were used in a detailed photodynamical modelling of the system and increased the accuracy of the derivable system parameters.
- ID:
- ivo://CDS.VizieR/J/AJ/149/150
- Title:
- Photometry of multiples at NAOR and ASV in 2012
- Short Name:
- J/AJ/149/150
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the 2m telescope of the Bulgarian National Astronomical Observatory at Rozhen, observations of 246 double or multiple stars were carried out during six nights in 2012. This is the seventh series of measurements of CCD frames of double and multiple stars obtained at Rozhen. Also in 2012, using the 0.6m telescope of the Serbian Astronomical Station on the mountain of Vidojevica, observations of 117 double or multiple stars were carried out during five nights. This is the second series of measurements of CCD frames of double and multiple stars obtained at this station. In this paper we present the results for the position angle and angular separation for 453 pairs and residuals for 105 pairs with published orbital elements or linear solutions. These observations have angular separations in the range from 1.50'' to 178.12'', with a median angular separation of 8.13''. We also present the recalculated linear solution for one pair and three linear solutions that have been calculated for the first time.
- ID:
- ivo://CDS.VizieR/J/AJ/153/195
- Title:
- Photometry of multiple stars at NAOR&ASV in 2015
- Short Name:
- J/AJ/153/195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of CCD observations of 154 double or multiple stars, made with the 2 m telescope of the Bulgarian National Astronomical Observatory at Rozhen over five nights in 2015, are presented. This is the ninth series of measurements of CCD frames obtained at Rozhen. We also present results of CCD observations of 323 double or multiple stars made with the 0.6 m telescope of the Serbian Astronomical Station on the mountain of Vidojevica over 23 nights in 2015. This is the fourth series of measurements of CCD frames obtained at this station. This paper contains the results for the position angle and angular separation for 801 pairs and residuals for 127 pairs with published orbital elements or linear solutions. The angular separations are in the range from 1.52" to 201.56", with a median angular separation of 8.26". We also present eight pairs that are measured for the first time and linear elements for five pairs.
- ID:
- ivo://CDS.VizieR/J/AJ/151/58
- Title:
- Photometry of stars at NAOR and ASV in 2013-2014
- Short Name:
- J/AJ/151/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the 2m telescope of the Bulgarian National Astronomical Observatory at Rozhen, observations of 271 double or multiple stars were carried out during seven nights in 2013 and 2014. This is the eighth series of measurements of CCD frames of double and multiple stars obtained at Rozhen. Also in 2013 and 2014, using the 0.6m telescope of the Serbian Astronomical Station on the mountain of Vidojevica, observations of 343 double or multiple stars were carried out during 21 nights. This is the third series of measurements of CCD frames of double and multiple stars obtained at this station. In this paper, we present the results for the position angle and angular separation for 721 pairs and residuals for 126 pairs with published orbital elements or linear solutions. These observations have angular separations in the range from 1.24'' to 202.30'', with a median angular separation of 7.17''. We also present eight linear solutions that have been calculated for the first time.
- ID:
- ivo://CDS.VizieR/J/AJ/158/215
- Title:
- Photometry of stars at NAOR and ASV in 2017-2018
- Short Name:
- J/AJ/158/215
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We give the results of CCD observations for 789 double or multiple stars obtained during 2017 and 2018. These observations were carried out at both the Serbian Astronomical Station on the mountain of Vidojevica (ASV) and the Bulgarian National Astronomical Observatory at Rozhen (NAOR). They were performed using three telescopes, the 1.4 and 0.6 m telescopes at ASV, and the 2 m telescope at NAOR. The total of 1196 measurements (position angle and angular separation) for the 939 pairs is presented. Out of this number, 55 pairs have calculated orbital or linear elements and for them the residuals are given. Some pairs have measurements for several epochs. Measured angular separations are in the interval from 1.51" to 208.81", with a median separation of 4.16". Two new pairs and linear elements for three pairs, which are calculated for the first time, are also presented.
- ID:
- ivo://CDS.VizieR/J/AJ/161/221
- Title:
- Photometry & spectroscopy of 4 binaries stars
- Short Name:
- J/AJ/161/221
- Date:
- 16 Mar 2022 11:53:19
- Publisher:
- CDS
- Description:
- We present the photometric and spectroscopic analysis of four W-UMa binaries J015829.5+260333 (hereinafter as J0158), J030505.1+293443 (hereinafter as J0305), J102211.7+310022 (hereinafter as J1022), and KW-Psc. The VRcIc band photometric observations are carried out with the 1.3m Devasthal Fast Optical Telescope (DFOT). For low-resolution spectroscopy, we used the 2m Himalayan Chandra Telescope (HCT) as well as the archival data from the 4m LAMOST survey. The systems J0158 and J0305 show a period increase rate of 5.26({+/-}1.72)x10^-7^days/yr and 1.78({+/-}1.52)x10^-6^days/yr, respectively. The period of J1022 is found to be decreasing with a rate of 4.22({+/-}1.67)x10^-6^days/yr. The period analysis of KW-Psc displays no change in its period. The PHOEBE package is used for the light-curve modeling and basic parameters are evaluated with the help of the GAIA parallax. The asymmetry of light curves is explained with the assumption of cool spots at specific positions on one of the components of the system. On the basis of temperatures, mass ratios, fill-out factors, and periods, the system J1022 is identified as a W-subtype system while the others show some mixed properties. To probe the chromospheric activities in these W-UMa binaries, their spectra are compared with the known inactive stars' spectra. The comparison shows emission in H{alpha}, H{beta}, and CaII. To understand the evolutionary status of these systems, the components are plotted in mass-radius and mass-luminosity planes with other well characterized binary systems. The secondary components of all the systems are away from ZAMS, which indicates that the secondary is more evolved than the primary component.
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/1291
- Title:
- Physical properties of 38 exoplanets
- Short Name:
- J/MNRAS/426/1291
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- I measure the physical properties of 38 transiting extrasolar planetary systems, bringing the total number studied within the Homogeneous Studies project to 82. Transit light curves are modelled using the jktebop code, with careful attention paid to limb darkening, orbital eccentricity and contaminating light. The physical properties of each system are obtained from the photometric parameters, published spectroscopic measurements and five sets of theoretical stellar model predictions. Statistical errors are assessed using Monte Carlo and residual permutation algorithms and propagated via a perturbation algorithm. Systematic errors are estimated from the interagreement between results calculated using five theoretical stellar models. I present the first results based on Kepler short-cadence data for Kepler-14, Kepler-15 and KOI-135.
- ID:
- ivo://CDS.VizieR/J/A+A/587/A64
- Title:
- Physical properties of giant exoplanets
- Short Name:
- J/A+A/587/A64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- While giant extrasolar planets have been studied for more than two decades now, there are still some open questions as to their dominant formation and migration processes, as well as to their atmospheric evolution in different stellar environments. In this paper, we study a sample of giant transiting exoplanets detected by the Kepler telescope with orbital periods up to 400 days. We first defined a sample of 129 giant-planet candidates that we followed up with the SOPHIE spectrograph (OHP, France) in a 6-year radial velocity campaign. This allowed us to unveil the nature of these candidates and to measure a false-positive rate of 54.6+/-6.5% for giant-planet candidates orbiting within 400 days of period. Based on a sample of confirmed or likely planets, we then derived the occurrence rates of giant planets in different ranges of orbital periods. The overall occurrence rate of giant planets within 400 days is 4.6+/-0.6%. We recovered, for the first time in the Kepler data, the different populations of giant planets reported by radial velocity surveys. Comparing these rates with other yields, we find that the occurrence rate of giant planets is lower only for hot Jupiters but not for the longer-period planets. We also derive a first measurement of the occurrence rate of brown dwarfs in the brown-dwarf desert with a value of 0.29+/-0.17%. Finally, we discuss the physical properties of the giant planets in our sample. We confirm that giant planets receiving moderate irradiation are not inflated, but we find that they are on average smaller than predicted by formation and evolution models. In this regime of low-irradiated giant planets, we find a possible correlation between their bulk density and the iron abundance of the host star, which needs more detections to be confirmed.
