- ID:
- ivo://CDS.VizieR/J/ApJ/709/168
- Title:
- Eccentric orbits in exoplanets
- Short Name:
- J/ApJ/709/168
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Doppler technique measures the reflex radial motion of a star induced by the presence of companions and is the most successful method to detect exoplanets. If several planets are present, their signals will appear combined in the radial motion of the star, leading to potential misinterpretations of the data. Specifically, two planets in 2:1 resonant orbits can mimic the signal of a single planet in an eccentric orbit. We quantify the implications of this statistical degeneracy for a representative sample of the reported single exoplanets with available data sets, finding that (1) around 35% of the published eccentric one-planet solutions are statistically indistinguishable from planetary systems in 2:1 orbital resonance, (2) another 40% cannot be statistically distinguished from a circular orbital solution, and (3) planets with masses comparable to Earth could be hidden in known orbital solutions of eccentric super-Earths and Neptune mass planets.
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- ID:
- ivo://CDS.VizieR/V/64
- Title:
- Eighth Orbital Elements of Spectroscopic Binaries
- Short Name:
- V/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The complete description of the catalogue, as well as the notes, is to be found in the Publ. Dominion Astrophys. Obs. 17 (1989). The present machine-readable version was transformed from the file provided by A.H. Batten for easier computer readability. Compared to the printed version, please note the following: 1) The four columns No. f(m) m.sin^3(i) a.sin(i) are NOT included in the computer version. No. (running number) is the line number of the main file (from 1 to 1469) f(m) (expressed in Solar Masses) can be computed from the Fortran formula 1.0385E-7 * (1-e*e)**1.5 * K(1)**3 * P a(*)sin i (expressed in km) can be computed from the Fortran formula 13751 * sqrt(1-e*e) * K(*) * P m(*)sin3i (expressed in Solar Masses) can be computed from the Fortran formula 1.0385E-7 * (1-e*e)**1.5 * K(*) * (K(1)+K(2))**2 * P The parameters are K(*) = velocity amplitude of the components, expressed in km/s; P = Period, expressed in days, sometimes in years; e = eccentricity 2) The notes, which make the bulk of the printed catalogue (pages 129-304), are NOT included.
- ID:
- ivo://CDS.VizieR/J/A+A/574/A39
- Title:
- Exoplaneraty systems fundamental parameters
- Short Name:
- J/A+A/574/A39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We assess the importance of tidal evolution and its interplay with magnetic braking in the population of hot-Jupiter planetary systems. By minimizing the total mechanical energy of a given system under the constraint of stellar angular momentum loss, we rigorously find the conditions for the existence of dynamical equilibrium states. We estimate their duration, in particular when the wind torque spinning down the star is almost compensated for by the tidal torque spinning it up. We introduce dimensionless variables to characterize the tidal evolution of observed hot Jupiter systems and discuss their spin and orbital states using generalized Darwin diagrams based on our new approach. We show that their orbital properties are related to the effective temperature of their host stars. The long-term evolution of planets orbiting F- and G-type stars is significantly different owing to the combined effect of magnetic braking and tidal dissipation. The existence of a quasi-stationary state, in the case of short-period planets, can significantly delay their tidal evolution that would otherwise bring the planet to fall into its host star. Most of the planets known to orbit F-type stars are presently found to be near this stationary state, probably in a configuration not too far from what they had when their host star settled on the zero-age main sequence. Considering the importance of angular momentum loss in the early stages of stellar evolution, our results indicate that it has to be considered to properly test the migration scenarios of planetary system formation.
- ID:
- ivo://CDS.VizieR/J/MNRAS/459/4360
- Title:
- Field RR Lyrae stars
- Short Name:
- J/MNRAS/459/4360
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents an extensive overview of known and proposed RR Lyrae stars in binaries. The aim is to revise and extend the list with new Galactic field systems. We utilized maxima timings for 11 RRab type stars with suspicious behaviour from the GEOS database, and determined maxima timings from data of sky surveys and our own observations. This significantly extended the number of suitable maxima timings. We modelled the proposed Light Time Effect (LiTE) in O-C diagrams to determine orbital parameters for these systems. In contrast to recent studies, our analysis focused on decades-long periods instead of periods in the order of years. Secondary components were found to be predominantly low-mass objects. However, for two of the stars, RZ Cet and AT Ser, the mass of the suspected companion of more than one solar mass suggests that it is a massive white dwarf, a neutron star or even a black hole. We found that the semi-major axes of the proposed orbits are between 1 and 20au. Because the studied stars belong to the closest RR Lyraes, maximal angular distances between components during orbit should at least be between 1 and 13mas and this improves the chance to detect both stars using current telescopes and interferometers. However, our interpretation of the O-C diagrams as a consequence of the LiTE should be considered as preliminary without reliable spectroscopic measurements. On the other hand, our models give a prediction of the period and radial velocity evolution which should be sufficient for plausible proof of binarity.
- ID:
- ivo://CDS.VizieR/VI/44
- Title:
- Finding List of Interacting Binaries, 5th ed.
- Short Name:
- VI/44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog is abstracted from the Card Catalog maintained at the University of Florida containing information on all published, and to the extent available, unpublished work on eclipsing binaries. The fifth edition differs from the previous ones in the extension of the magnitude limit at maximum light from 13 to 15. The catalog fields are Finding List number; star name; position (equinox 1900); blue magnitude at maximum light; bandpass of maximum light; depth of primary minimum in same bandpass; bandpass primary minimum; depth of secondary minimum and its bandpass; spectral class of star eclipsed at primary light and optional uncertainty character; spectral class of star eclipsed at secondary light; most recent reliable epoch of primary minimum; most recent orbital period; duration of primary minimum; duration of totality of primary minimum; BD, CoD, CPD, and HD number; alternate designations of system; codes indicating the nature of the system.
- ID:
- ivo://CDS.VizieR/J/A+A/624/A118
- Title:
- Fitted orbits and parameters of 51 Eridani b
- Short Name:
- J/A+A/624/A118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 51 Eridani observations were performed with the VLT exoplanet imager SPHERE for 3 years in order to monitor the orbital motion of the known giant planet and refine its orbital parameters. We carried out an orbital analysis using three complementary approaches (LSMC, MCMC, Bayesian rejection sampling) and found broadly similar results. The data suggest a period of 23-49yr (i.e. semi-major axis of 10-16au), an inclination of 126-147{deg}, an eccentricity of 0.30-0.55, and an argument at periastron of 57-121{deg} (mod 180{deg}). The time at periastron and the longitude of node exhibit bimodal distributions.
- ID:
- ivo://CDS.VizieR/J/ApJS/235/41
- Title:
- Galactic EB stars with eccentric orbits based on ETDs
- Short Name:
- J/ApJS/235/41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A comprehensive catalog of 623 galactic eclipsing binary (EB) systems with eccentric orbits is presented with more than 2830 times of minima determined from the archived photometric data by various sky-survey projects and new photometric measurements. The systems are divided into two groups according to whether the individual system has a GCVS name or not. All the systems in both groups are further classified into three categories (D, A, and A+III) on the basis of their eclipse timing diagrams: 453 D systems showing just constantly displaced secondary minima, 139 A systems displaying only apsidal motion (AM), and 31 A+III systems exhibiting both AM and light-time effects. AM parameters for 170 systems (A and A+III systems) are consistently calculated and cataloged with basic information for all systems. Some important statistics for the AM parameters are discussed and compared with those derived for the eccentric EB systems in the Large and Small Magellanic Clouds.
- ID:
- ivo://CDS.VizieR/J/ApJ/649/1010
- Title:
- Habitability of known exoplanetary systems
- Short Name:
- J/ApJ/649/1010
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Habitable planets are likely to be broadly Earth-like in composition, mass, and size. Masses are likely to be within a factor of a few of the Earth's mass. Currently, we do not have sufficiently sensitive techniques to detect Earth-mass planets, except in rare circumstances. It is thus necessary to model the known exoplanetary systems. In particular, we need to establish whether Earth-mass planets could be present in the classical habitable zone (HZ) or whether the giant planets that we know to be present would have gravitationally ejected Earth-mass planets or prevented their formation. We have answered this question by applying computer models to the 152 exoplanetary systems known by 2006 April 18 that are sufficiently well characterized for our analysis. For systems in which there is a giant planet, inside the HZ, which must have arrived there by migration, there are two cases: (1) where the migration of the giant planet across the HZ has not ruled out the existence of Earth-mass planets in the HZ; and (2) where the migration has ruled out existence. For each case, we have determined the proportion of the systems that could contain habitable Earth-mass planets today, and the proportion for which this has been the case for at least the past 1000Myr (excluding any early heavy bombardment). For case 1 we get 60% and 50%, respectively, and for case 2 we get 7% and 7%, respectively.
- ID:
- ivo://CDS.VizieR/J/A+A/299/621
- Title:
- Is Sirius a triple star?
- Short Name:
- J/A+A/299/621
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Sirius has been discovered as double more than 130 years ago. From the beginning of our century up to now, observational as well as physical and dynamical indications lead to the hypothesis of the existence of a third body in the system. In this paper, we present recent orbital analysis of the binary Sirius A-B which, helped by numerical simulation of triple systems, strengthens the idea for the triplicity of Sirius: a tiny star could revolve in about 6 years around Sirius A. Finally, we discuss the possibility of direct detection for this suspected Sirius C.
- ID:
- ivo://CDS.VizieR/J/MNRAS/421/2616
- Title:
- LMC eccentric ellipsoidal red giant binaries
- Short Name:
- J/MNRAS/421/2616
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Modelling ellipsoidal variables with known distances can lead to exact determination of the masses of both components, even in the absence of eclipses. We present such modelling using light and radial velocity curves of ellipsoidal red giant binaries in the Large Magellanic Cloud (LMC), where they are also known as sequence E stars. Stars were selected as likely eccentric systems on the basis of light curve shape alone. We have confirmed their eccentric nature and obtained system parameters using the Wilson-Devinney code.
