- ID:
- ivo://CDS.VizieR/J/MNRAS/448/2890
- Title:
- Observation of six NSVS eclipsing binaries
- Short Name:
- J/MNRAS/448/2890
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out photometric and low-resolution spectral observations of six eclipsing ultrashort-period binaries with main-sequence (MS)components. The light-curve solutions of the Rozhen observations show that all targets are overcontact systems. We found a well-defined empirical relation between period and semi-major axis for the short-period binaries and used it for estimation of the global parameters of the targets. Our results revealed that NSVS 925605 is quite an interesting target: (i) it is one of a few contact binaries with M components; (ii) it exhibits high activity (emission in the H{alpha} line, X-ray emission, large cool spots, non-Planck energy distribution); (iii) its components differ in temperature by 700 K. All the appearances of high magnetic activity and the huge fill-out factor (0.7) of NSVS 925605 may be a precursor of the predicted merging of close magnetic binaries. Another unusual binary is NSVS 2700153, which reveals considerable long-term variability.
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- ID:
- ivo://CDS.VizieR/J/AJ/153/212
- Title:
- Observations of binary stars at the WIYN telescope
- Short Name:
- J/AJ/153/212
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on speckle observations of binary stars carried out at the WIYN Telescope over the period from 2010 September through 2012 February, providing relative astrometry for 2521 observations of 883 objects, 856 of which are double stars and 27 of which are triples. The separations measured span a range of 0.01-1.75 arcsec. Wavelengths of 562, 692, and 880 nm were used, and differential photometry at one or more of these wavelengths is presented in most cases. 66 components were resolved for the first time. We also estimate detection limits at 0.2 and 1.0 arcsec for high-quality observations in cases where no companion was seen, a total of 176 additional objects. Detection limits vary based on observing conditions and signal-to-noise ratio, but are approximately 4 mag at 0.2 arcsec and 6 mag at 1.0 arcsec on average. Analyzing the measurement precision of the data set, we find that the individual separations obtained have linear measurement uncertainties of approximately 2 mas, and photometry is uncertain to approximately 0.1 mag in general. This work provides fundamental, well-calibrated data for future orbit and mass determinations, and we present three first orbits and total mass estimates of nearby K-dwarf systems as examples of this potential.
- ID:
- ivo://CDS.VizieR/J/AJ/159/233
- Title:
- Observations of binary stars with the DSSI. IX.
- Short Name:
- J/AJ/159/233
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report 370 measures of 170 components of binary and multiple-star systems, obtained from speckle imaging observations made with the Differential Speckle Survey Instrument (DSSI) at Lowell Observatory's Discovery Channel Telescope in 2015 through 2017. Of the systems studied, 147 are binary stars, 10 are seen as triple systems, and 1 quadruple system is measured. Seventy-six high-quality nondetections and 15 newly resolved components are presented in our observations. The uncertainty in relative astrometry appears to be similar to our previous work at Lowell, namely, linear measurement uncertainties of approximately 2mas, and the relative photometry appears to be uncertain at the 0.1-0.15mag level. Using these measures and those in the literature, we calculate six new visual orbits, including one for the Be star 66Oph and two combined spectroscopic-visual orbits. The latter two orbits, which are for HD22451 (YSC127) and HD185501 (YSC135), yield individual masses of the components at the level of 2% or better, and independent distance measures that in one case agrees with the value found in the Gaia DR2 and in the other disagrees at the 2{sigma} level. We find that HD22451 consists of an F6V+F7V pair with orbital period of 2401.1{+/-}3.2days and masses of 1.342{+/-}0.029 and 1.236{+/-}0.026M_{sun}_. For HD185501, both stars are G5 dwarfs that orbit one another with a period of 433.94{+/-}0.15days, and the masses are 0.898{+/-}0.012 and 0.876{+/-}0.012M_{sun}_. We discuss the details of both the new discoveries and the orbit objects.
- ID:
- ivo://CDS.VizieR/J/AJ/134/2353
- Title:
- Observations of contact binaries
- Short Name:
- J/AJ/134/2353
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of the Canada-France-Hawaii Telescope adaptive optics (AO) search for companions of a homogeneous group of contact binary stars, as a contribution to our attempts to prove the hypothesis that these binaries require a third star to become as close as observed.
- ID:
- ivo://CDS.VizieR/J/ApJS/105/475
- Title:
- Observations of double stars. XVII.
- Short Name:
- J/ApJS/105/475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Micrometer observations of 722 doubles, including 14 new pairs, in 1994-1995 are tabulated, along with some orbits.
- ID:
- ivo://CDS.VizieR/J/ApJS/117/587
- Title:
- Observations of double stars. XVIII.
- Short Name:
- J/ApJS/117/587
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Micrometer observations of 1350 pairs in 1995-1997 are listed.
- ID:
- ivo://CDS.VizieR/J/A+A/502/695
- Title:
- Observations of HD 80606 planetary system
- Short Name:
- J/A+A/502/695
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We recently reported the photometric and spectroscopic detection of the primary transit of the 111-day-period, eccentric extra-solar planet HD 80606b, at Observatoire de Haute-Provence, France. The whole egress of the primary transit and a section of its central part were observed, allowing the measurement of the planetary radius, and evidence for a spin-orbit misalignment through the observation of the Rossiter-McLaughlin anomaly. The ingress not having been observed for this long-duration transit, uncertainties remained in the parameters of the system. We present here a refined, combined analysis of our photometric and spectroscopic data, together with further published radial velocities, ground-based photometry, and Spitzer photometry around the secondary eclipse, as well as new photometric measurements of HD 80606 acquired at Mount Hopkins, Arizona, just before the beginning of the primary transit.
- ID:
- ivo://CDS.VizieR/J/A+A/500/L45
- Title:
- Observations of transits of the TrES-2 exoplanet
- Short Name:
- J/A+A/500/L45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a possible change in the orbit parameters of the TrES-2 exoplanet. With a period of 2.470621 days, the TrES-2 exoplanet exhibits almost "grazing" transits 110.4-minutes duration as measured in 2006 by Holman and collaborators (2007, Cat. <J/ApJ/664/1185>). We observed two transits of TrES-2 in 2008 using the 1.2m Oskar-Luhning telescope (OLT) of Hamburg observatory employing CCD photometry in an i-band and a near to R-band filter. A careful lightcurve analysis including a re-analys is of the 2006 observations shows that the current transit duration has shortened since 2006 by ~3.16-minutes. Although the new observations were taken in a different filter we argue that the observed change in transit duration time cannot be attributed to the treatment of limb darkening. If we assume the stellar and planetary radii to be constant, a change in orbit inclination is the most likely cause of this change in transit duration.
- ID:
- ivo://CDS.VizieR/J/ApJ/722/880
- Title:
- Observations of two transits of HD 80606b
- Short Name:
- J/ApJ/722/880
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present ground-based optical observations of the 2009 September and 2010 January transits of HD 80606b. Based on three partial light curves of the 2009 September event, we derive a midtransit time of T_c_[HJD]=2455099.196+/-0.026, which is about 1{sigma} away from the previously predicted time. We observed the 2010 January event from nine different locations, with most phases of the transit being observed by at least three different teams. We determine a midtransit time of T_c_[HJD]=2455210.6502+/-0.0064, which is within 1.3{sigma} of the time derived from a Spitzer observation of the same event.
- ID:
- ivo://CDS.VizieR/J/ApJ/629/507
- Title:
- Observed orbital eccentricities for 391 binaries
- Short Name:
- J/ApJ/629/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For 391 spectroscopic and visual binaries with known orbital elements and having B0-F0 IV or V primaries, we collected the derived eccentricities. As has been found by others, those binaries with periods of a few days have been circularized. However, those with periods up to about 1000 or more days show reduced eccentricities that asymptotically approach a mean value of 0.5 for the longest periods. For those binaries with periods greater than 1000 days their distribution of eccentricities is flat from 0 to nearly 1, indicating that in the formation of binaries there is no preferential eccentricity. The binaries with intermediate periods (10-100 days) lack highly eccentric orbits.
