- ID:
- ivo://CDS.VizieR/J/A+A/525/A66
- Title:
- 4 close binaries BVR light curves
- Short Name:
- J/A+A/525/A66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze new multicolor light curves and recently published radial velocity curves for close binaries QX And, RW Com, MR Del, and BD +07 3142 to determine the physical parameters of the components. The light curves are analyzed using a binary star model based on Roche geometry to fit the photometric observations. Spectroscopic parameters, such as the mass ratios and spectral types, were taken from recent spectroscopic studies of the systems in question.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/PAZh/27/632
- Title:
- Close binary system BZ Mon
- Short Name:
- J/PAZh/27/632
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of a UBVR photometry observations and light curve analysis are presented for eclipsing binary, BZ Mon.
- ID:
- ivo://CDS.VizieR/J/PAZh/27/442
- Title:
- Close binary system EQ Ori
- Short Name:
- J/PAZh/27/442
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of a UBVR photometry observations are presented for eclipsing variable EQ Ori. The binary was observed 1988 with the 1-m telescope at Maidanak Observatory (Uzbekistan).
- ID:
- ivo://CDS.VizieR/J/AJ/131/1674
- Title:
- Close binary systems from SDSS DR4
- Short Name:
- J/AJ/131/1674
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic sample of 746 detached close binary systems from the Sloan Digital Sky Survey (SDSS) Fourth Data Release (2006ApJS..162...38A). The majority of these binaries consist of a white dwarf primary and a low-mass secondary (typically M dwarf) companion. We have determined the temperature and gravity for 496 of the white dwarf primaries and the spectral type and magnetic activity properties for 661 of the low-mass secondaries. We have estimated the distances for each of the white dwarf-main-sequence star binaries and use white dwarf evolutionary grids to establish the age of each binary system from the white dwarf cooling times.
- ID:
- ivo://CDS.VizieR/J/PAZh/23/458
- Title:
- Close binary system V502 Cyg in Cyg T2
- Short Name:
- J/PAZh/23/458
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photoelectric UBVR observations of the short period close binary system V502 Cyg in the T association Cyg T2 are presented.
- ID:
- ivo://CDS.VizieR/J/AJ/157/196
- Title:
- Close companions around young stars
- Short Name:
- J/AJ/157/196
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Multiplicity is a fundamental property that is set early during stellar lifetimes, and it is a stringent probe of the physics of star formation. The distribution of close companions around young stars is still poorly constrained by observations. We present an analysis of stellar multiplicity derived from Apache Point Observatory Galactic Evolution Experiment-2 spectra obtained in targeted observations of nearby star-forming regions. This is the largest homogeneously observed sample of high-resolution spectra of young stars. We developed an autonomous method to identify double-lined spectroscopic binaries (SB2s). Out of 5007 sources spanning the mass range of ~0.05-1.5 M_{sun}_, we find 399 binaries, including both radial velocity (RV) variables and SB2s. The mass ratio distribution of SB2s is consistent with being uniform for q<0.95 with an excess of twins for q>0.95. The period distribution is consistent with what has been observed in close binaries (<10 au) in the evolved populations. Three systems are found to have q~0.1, with a companion located within the brown dwarf desert. There are no strong trends in the multiplicity fraction as a function of cluster age from 1 to 100 Myr. There is a weak dependence on stellar density, with companions being most numerous at {Sigma}_*_~30 stars/pc^-2^ and decreasing in more diffuse regions. Finally, disk-bearing sources are deficient in SB2s (but not RV variables) by a factor of ~2; this deficit is recovered by the systems without disks. This may indicate a quick dispersal of disk material in short-period equal-mass systems that is less effective in binaries with lower q.
- ID:
- ivo://CDS.VizieR/J/ApJ/745/119
- Title:
- Close companions to young stars. I. ChaI & Tau
- Short Name:
- J/ApJ/745/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a multiplicity survey of 212 T Tauri stars in the Chamaeleon I and Taurus-Auriga star-forming regions, based on high-resolution spectra from the Magellan Clay 6.5m telescope. From these data, we achieved a typical radial velocity (RV) precision of ~80m/s with slower rotators yielding better precision, in general. For 174 of these stars, we obtained multi-epoch data with sufficient time baselines to identify binaries based on RV variations. We identified eight close binaries and four close triples, of which three and two, respectively, are new discoveries. The spectroscopic multiplicity fractions we find for Chamaeleon I (7%) and Taurus-Auriga (6%) are similar to each other, and to the results of field star surveys in the same mass and period regime. However, unlike the results from imaging surveys, the frequency of systems with close companions in our sample is not seen to depend on primary mass. Additionally, we do not find a strong correlation between accretion and close multiplicity. This implies that close companions are not likely the main source of the accretion shut down observed in weak-lined T Tauri stars. Our results also suggest that sufficient RV precision can be achieved for at least a subset of slowly rotating young stars to search for hot Jupiter planets.
3468. Close double stars
- ID:
- ivo://CDS.VizieR/V/42
- Title:
- Close double stars
- Short Name:
- V/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is a new edition of the catalogue of the photometric and absolute elements of close double systems by Svechnikov (ref 142). After the appearance of this catalogue(1969), the numerous new data concerning both photometric and spectroscopic elements of orbits of the eclipsing binaries were published. The precision of determination of the light curves of eclipsing systems is essentially augmented; now, the light curves of eclipsing binaries are obtained mainly by means of multicolour photoelectric observations; for a number of systems,e extra-atmospheric observations from satellites and orbital astronomical observatories are available. More details are available in original.txt.
- ID:
- ivo://CDS.VizieR/J/A+A/406/751
- Title:
- Close encounters of asteroids 2003-2020
- Short Name:
- J/A+A/406/751
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Selection have been made of asteroids-asteroids close encounters inducing perturbations large enough to deduce masses of perturbing objects. In tablea1.dat, and tablea3.dat, the epoch of encounters is given as well as the impact parameter, the relative distance and the criterion of maximum deflection (see section 2). The epoch of encounters is defined as the epoch when the relative distance or velocity between the two asteroids become minimum or the criterion of deflection becomes maximum. The ({Delta}{alpha},{Delta}{delta}) given in tables are the maximum differences in right ascension and declination between the perturbed and the unperturbed orbits and the epoch of maximum ({Delta}{alpha},{Delta}{delta}) is defined as the mean epoch for the maximum values of ({Delta}{alpha},{Delta}{delta}). Finally, in tablea2.dat and tablea4.dat, we give the observability of each encounters. We give the periods when the asteroids have a mean solar elongation greater than 50 degrees and when the perturbations of the orbits induced by the Multiple Gravitational Event (MGE) are greater than 50 mas. Mean values of these perturbations in right ascension and declination computed over the corresponding periods are given in Columns 4 and 5.
- ID:
- ivo://CDS.VizieR/J/A+A/616/A37
- Title:
- Close encounters to the Sun in Gaia DR2
- Short Name:
- J/A+A/616/A37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Passing stars may play an important role in the evolution of our solar system. We search for close stellar encounters to the Sun among all 7.2 million stars in Gaia DR2 that have six-dimensional phase space data. We characterize encounters by integrating their orbits through a Galactic potential and propagating the correlated uncertainties via a Monte Carlo resampling. After filtering to remove spurious data, we find 694 stars that have median (over uncertainties) closest encounter distances within 5pc, all occurring within 15Myr from now. 26 of these have at least a 50% chance of coming closer than 1pc (and 7 within 0.5pc), all but one of which are newly discovered here. We confirm some and refute several other previously-identified encounters, confirming suspicions about their data. The closest encounter in the sample is Gl 710, which has a 95% probability of coming closer than 0.08pc (17000AU). Taking mass estimates obtained from Gaia astrometry and multiband photometry for essentially all encounters, we find that Gl 710 also has the largest impulse on the Oort cloud. Using a Galaxy model, we compute the completeness of the Gaia DR2 encountering sample as a function of perihelion time and distance. Only 15% of encounters within 5pc occurring within +/-5Myr of now have been identified, mostly due to the lack of radial velocities for faint and/or cool stars. Accounting for the incompleteness, we infer the present rate of encounters within 1pc to be 19.7+/-2.2 per Myr, a quantity expected to scale quadratically with the encounter distance out to at least several pc. Spuriously large parallaxes in our sample from imperfect filtering would tend to inflate both the number of encounters found and this inferred rate. The magnitude of this effect is hard to quantify.
