- ID:
- ivo://CDS.VizieR/J/AJ/143/107
- Title:
- Radial velocities of TYC 4110-01037-1
- Short Name:
- J/AJ/143/107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- TYC 4110-01037-1 has a low-mass stellar companion, whose small mass ratio and short orbital period are atypical among binary systems with solar-like (T_eff_<~6000K) primary stars. Our analysis of TYC 4110-01037-1 reveals it to be a moderately aged (<~5Gyr) solar-like star having a mass of 1.07+/-0.08M_{sun}_ and radius of 0.99+/-0.18R_{sun}_. We analyze 32 radial velocity (RV) measurements from the SDSS-III MARVELS survey as well as 6 supporting RV measurements from the SARG spectrograph on the 3.6m Telescopio Nazionale Galileo telescope obtained over a period of ~2years. The best Keplerian orbital fit parameters were found to have a period of 78.994+/-0.012days, an eccentricity of 0.1095+/-0.0023, and a semi-amplitude of 4199+/-11m/s. We determine the minimum companion mass (if sini=1) to be 97.7+/-5.8M_Jup_. The system's companion to host star mass ratio, >=0.087+/-0.003, places it at the lowest end of observed values for short period stellar companions to solar-like (T_eff_<~6000K) stars. One possible way to create such a system would be if a triple-component stellar multiple broke up into a short period, low q binary during the cluster dispersal phase of its lifetime. A candidate tertiary body has been identified in the system via single-epoch, high contrast imagery. If this object is confirmed to be comoving, we estimate it would be a dM4 star. We present these results in the context of our larger-scale effort to constrain the statistics of low-mass stellar and brown dwarf companions to FGK-type stars via the MARVELS survey.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/645/A72
- Title:
- Radial velocities of UCAC4 721-037069
- Short Name:
- J/A+A/645/A72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Large radial velocity variations in the LAMOST spectra of giant stars have been used to infer the presence of unseen companions. Some of them have been proposed as possible black hole candidates. We test this selection by investigating the classification of the one candidate that has a known X-ray counterpart (UCAC4 721-037069). We obtained time-resolved spectra from the Liverpool Telescope and a 5 ks observation from the Chandra observatory to fully constrain the orbital parameters and the X-ray emission of this system. We find the source to be an eclipsing stellar binary that can be classified as an RS CVn. The giant star fills its Roche lobe, and the binary mass ratio is greater than one. The system may be an example of stable mass transfer from an intermediate-mass star with a convective envelope Using only radial velocity to identify black hole candidates can lead to many false positives. The presence of an optical orbital modulation, such as what has been observed for all LAMOST candidates, will in most cases indicate that the system is a stellar binary.
- ID:
- ivo://CDS.VizieR/J/A+A/459/849
- Title:
- Radial velocities of ups Sgr
- Short Name:
- J/A+A/459/849
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Binaries observed in the initial rapid phase of mass exchange between the components are very rare since the statistical probability of finding them is low. At the same time, thorough studies of them are extremely important for better understanding the process of large-scale mass exchange and possible mass loss from the system. One of these objects is probably upsilon Sgr. By analyzing 35 new electronic spectra and numerous published spectral and photometric observations, we derived the new orbital elements, an upper limit to a secular period change, and also the peculiar RV curve of the blue-shifted H{alpha} absorption. Possible models of the binary and its evolutionary stage are then discussed critically.
- ID:
- ivo://CDS.VizieR/J/A+A/370/974
- Title:
- Radial velocities of UX Ari
- Short Name:
- J/A+A/370/974
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- All radial velocities of the two components of UX Ari (RV_1_ referring to the cooler primary, RV_2_ to the hotter secondary) as measured or taken from the literature together with the errors given in the literature, measured for the new data or estimated for the very old data; additionally the subdivisions of the datasets are indicated.
- ID:
- ivo://CDS.VizieR/J/AJ/132/393
- Title:
- Radial velocities of V966 Her and V1438 Aql
- Short Name:
- J/AJ/132/393
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have examined the previously understudied Scuti stars V966 Herculis and V1438 Aquilae. We find that V966 Her is a stable pulsator with a refined period of 0.1330302 days with a full V amplitude of 0.096mag. We also find that V966 Her has an average radial velocity of +7.8km/s, a full radial velocity amplitude of 7.6km/s, and a vsini=63.8km/s. For V1438 Aql we report a revised Hipparcos period of 0.1612751 days with a full amplitude of 0.056. The average radial velocity is found to be -43km/s, with full amplitude of 9.7km/s, and a vsini=76.7km/s. Due to some anomalies seen in V1438 Aql we feel that a much larger photometric and spectroscopic campaign is required to determine the true nature of this star.
- ID:
- ivo://CDS.VizieR/J/ApJ/806/60
- Title:
- Radial velocities of 70 Vir (HD117176)
- Short Name:
- J/ApJ/806/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An on-going effort in the characterization of exoplanetary systems is the accurate determination of host star properties. This effort extends to the relatively bright host stars of planets discovered with the radial velocity method. The Transit Ephemeris Refinement and Monitoring Survey (TERMS) is aiding in these efforts as part of its observational campaign for exoplanet host stars. One of the first known systems is that of 70 Virginis, which harbors a jovian planet in an eccentric orbit. Here we present a complete characterization of this system with a compilation of TERMS photometry, spectroscopy, and interferometry. We provide fundamental properties of the host star through direct interferometric measurements of the radius (1.5% uncertainty) and through spectroscopic analysis. We combined 59 new Keck HIRES radial velocity measurements with the 169 previously published from the ELODIE, Hamilton, and HIRES spectrographs, to calculate a refined orbital solution and construct a transit ephemeris for the planet. These newly determined system characteristics are used to describe the Habitable Zone of the system with a discussion of possible additional planets and related stability simulations. Finally, we present 19 years of precision robotic photometry that constrain stellar activity and rule out central planetary transits for a Jupiter-radius planet at the 5{sigma} level, with reduced significance down to an impact parameter of b=0.95.
- ID:
- ivo://CDS.VizieR/J/AJ/156/231
- Title:
- Radial velocities of 2 VY Sculptoris-type CV stars
- Short Name:
- J/AJ/156/231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report observations of the known cataclysmic variable star (CV) V704 And, and also confirm that the optical counterpart of the ROSAT Galactic Plane Survey source RX J2338+431 is a heretofore-neglected CV. Photometric and spectroscopic observations from MDM Observatory show both systems to be nova-like variables that exhibit dips of 4-5 mag from their mean brightnesses, establishing them as members of the VY Scl subclass. From high-state emission-line radial velocities, we determine orbital periods of 0.151424(3) days (3.63 hr) for V704 And and 0.130400(1) days (3.13 hr) for RX J2338+431. In V704 And, we find that the H{alpha} emission-line measures cluster into distinct regions on a plot of equivalent width versus full width at half-maximum, which evidently correspond to high, intermediate, and low photometric states. This allows us to assign spectra to photometric states when contemporaneous photometry is not available, an apparently novel method that may be useful in studies of other novalikes. Our low-state spectra of RX J2338+431 show features of an M-type secondary star, from which we estimate a distance of 890+/-200 pc, in good agreement with the Gaia DR2 (Cat. I/345) parallax.
- ID:
- ivo://CDS.VizieR/J/A+A/517/L1
- Title:
- Radial velocities of WASP-8b planet
- Short Name:
- J/A+A/517/L1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of WASP-8, a transiting planet of 2.25+/-0.08M_{jup}_ on a strongly inclined eccentric 8.15-day orbit, moving in a retrograde direction to the rotation of its late-G host star. Evidence is found that the star is in a multiple stellar system with two other companions. The dynamical complexity of the system indicates that it may have experienced secular interactions such as the Kozai mechanism or a formation that differs from the "classical" disc-migration theory.
- ID:
- ivo://CDS.VizieR/J/AJ/129/2294
- Title:
- Radial velocities of weak-lines T Tauri stars
- Short Name:
- J/AJ/129/2294
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To search for thermal emission from substellar companions, we have obtained Z-band images of 15 weak-lined T Tauri stars in the Taurus-Auriga and Ophiuchus star-forming regions using the Planetary Camera 2 on the Hubble Space Telescope. To complement the imaging program, extensive spectroscopic observations were obtained with the Center for Astrophysics Digital Speedometers.
- ID:
- ivo://CDS.VizieR/J/MNRAS/455/1275
- Title:
- Radial velocities of WR21a
- Short Name:
- J/MNRAS/455/1275
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multi-epoch spectroscopic observations of the massive binary system WR21a, which include the 2011 January periastron passage. Our spectra reveal multiple SB2 lines and facilitate an accurate determination of the orbit and the spectral types of the components. We obtain minimum masses of 64.4+/-4.8M_{sun} and 36.3+/-1.7M_{sun} for the two components of WR21a. Using disentangled spectra of the individual components, we derive spectral types of O3/WN5ha and O3Vz ((f*)) for the primary and secondary, respectively. Using the spectral type of the secondary as an indication for its mass, we estimate an orbital inclination of i=58.8+/-2.5{deg} and absolute masses of 103.6+/-10.2M_{sun} and 58.3+/-3.7M_{sun}_, in agreement with the luminosity of the system. The spectral types of the WR21a components indicate that the stars are very young (1-2Myr), similar to the age of the nearby Westerlund 2 cluster. We use evolutionary tracks to determine the mass-luminosity relation for the total system mass. We find that for a distance of 8kpc and an age of 1.5Myr, the derived absolute masses are in good agreement with those from evolutionary predictions.
