- ID:
- ivo://CDS.VizieR/J/MNRAS/469/2089
- Title:
- Radial velocity curves of 7 KIC
- Short Name:
- J/MNRAS/469/2089
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present high- and middle-resolution spectral observations of seven heartbeat (HB), highly eccentric, Kepler binaries: four of them (KIC 3230227, KIC 03547874, KIC 03749404, KIC 07672068) are SB2 stars and the remaining three (KIC 04949194, KIC 05960989, KIC 10092506) are SB1 stars. The flux amplitudes of their HB signals are from 0.001 to 0.01. Five targets of the sample with eccentricity above 0.64 show tidally induced oscillations, which are harmonics of the orbital period. The orbital and global parameters of all targets were determined as a result of simultaneous modelling of our spectral observations and Kepler photometric data. They exhibit that the masses and radii of some target components do not obey the temperature-mass-radius relation of main-sequence stars. Although our targets do not obey precisely the theoretical period-eccentricity relation, they confirm the previous conclusion that HB stars draw the upper envelope of the eccentricity-period distribution. We did not find simple empirical dependences of the amplitude of the HB signal on the orbital and global parameters of the targets.
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- ID:
- ivo://CDS.VizieR/J/AJ/148/118
- Title:
- Radial velocity curves of LMC ellipsoidal variables
- Short Name:
- J/AJ/148/118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Ellipsoidal red giant binaries are close binary systems where an unseen, relatively close companion distorts the red giant, leading to light variations as the red giant moves around its orbit. These binaries are likely to be the immediate evolutionary precursors of close binary planetary nebula and post-asymptotic giant branch and post-red giant branch stars. Due to the MACHO and OGLE photometric monitoring projects, the light variability nature of these ellipsoidal variables has been well studied. However, due to the lack of radial velocity curves, the nature of their masses, separations, and other orbital details has so far remained largely unknown. In order to improve this situation, we have carried out spectral monitoring observations of a large sample of 80 ellipsoidal variables in the Large Magellanic Cloud and we have derived radial velocity curves. At least 12 radial velocity points with good quality were obtained for most of the ellipsoidal variables. The radial velocity data are provided with this paper. Combining the photometric and radial velocity data, we present some statistical results related to the binary properties of these ellipsoidal variables.
- ID:
- ivo://CDS.VizieR/J/MNRAS/460/3706
- Title:
- Radial velocity curves of {nu} Oct
- Short Name:
- J/MNRAS/460/3706
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report 1212 radial-velocity (RV) measurements obtained in the years 2009-2013 using an iodine cell for the spectroscopic binary {nu} Octantis (K1 III/IV). This system (a_bin_~2.6au, P~1050d) is conjectured to have a Jovian planet with a semimajor axis half that of the binary host. The extreme geometry only permits long-term stability if the planet is in a retrograde orbit. Whilst the reality of the planet (P~415d) remains uncertain, other scenarios (stellar variability or apsidal motion caused by a yet unobserved third star) continue to appear substantially less credible based on cross-correlation function bisectors, line-depth ratios and many other independent details. If this evidence is validated but the planet is disproved, the claims of other planets using RVs will be seriously challenged. We also describe a significant revision to the previously published RVs and the full set of 1437 RVs now encompasses nearly 13 yr. The sensitive orbital dynamics allow us to constrain the 3D architecture with a broad prior probability distribution on the mutual inclination, which with posterior samples obtained from an N-body Markov chain Monte Carlo is found to be 152.5^+0.7^_-0.6_{deg}. None of these samples are dynamically stable beyond 10^6^yr. However, a grid search around the best-fitting solution finds a region that has many models stable for 10^7^yr, and includes one model within 1{sigma} that is stable for at least 10^8^yr. The planet's exceptional nature demands robust independent verification and makes the theoretical understanding of its formation a worthy challenge.
- ID:
- ivo://CDS.VizieR/J/A+A/648/A58
- Title:
- Radial velocity curves of 4 stars
- Short Name:
- J/A+A/648/A58
- Date:
- 07 Dec 2021 08:07:13
- Publisher:
- CDS
- Description:
- We present the current status of and new results from our search for exoplanets in a sample of solar-mass evolved stars observed with the HARPS-N and the 3.6m Telescopio Nazionale Galileo (TNG), and the High-Resolution Spectrograph (HRS) and the 9.2m Hobby-Eberly Telescope (HET). The aim of this project is to detect and characterize planetary-mass companions to solar-mass stars in a sample of 122 targets at various stages of evolution from the main sequence (MS) to the red giant branch (RGB), mostly subgiants and giants, selected from the Pennsylvania-Torun Planet Search (PTPS) sample, and to use this sample to study relations between stellar properties, such as metallicity, luminosity, and the planet occurrence rate. This work is based on precise radial velocity (RV) measurements. We have observed the program stars for up to 14 years with the HET/HRS and the TNG/HARPS-N. We present the analysis of RV measurements with the HET/HRS and the TNG/HARPS-N of four solar-mass stars, HD 4760, HD 96992 , BD+02 3313, and TYC 0434-04538-1. We found that HD 4760 hosts a companion with a minimum mass of 13.9M_J_) (a=1.14au, e=0.23); HD 96992 is a host to a msini=1.14M_J_ companion on an a=1.24au and e=0/41 orbit, and TYC 0434-04538-1 hosts an msini=6.1M_J_ companion on an a=0.66au and e=0.08 orbit. In the case of BD+02 3313 we found a correlation between the measured RVs and one of the stellar activity indicators, suggesting that the observed RV variations may either originate in stellar activity or be caused by the presence of an unresolved companion. We also discuss the current status of the project and a statistical analysis of the RV variations in our sample of target stars. In our sample of 122 solar-mass stars, 49+/-5% of them appear to be single and 16+/-3% spectroscopic binaries. The three giants hosting low-mass companions presented in this paper join the six previously identified giants in the sample.
- ID:
- ivo://CDS.VizieR/J/A+A/505/1311
- Title:
- Radial velocity curves of 11 UMa and HD 32518
- Short Name:
- J/A+A/505/1311
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 11 UMi and HD 32518 belong to a sample of 62 K giant stars that has been observed since February 2004 using the 2m Alfred Jensch telescope of the Thueringer Landessternwarte (TLS) to measure precise radial velocities (RVs). The aim of this survey is to investigate the dependence of planet formation on the mass of the host star by searching for planetary companions around intermediate-mass giants.
- ID:
- ivo://CDS.VizieR/J/A+A/377/925
- Title:
- Radial velocity curves of Vela X-1
- Short Name:
- J/A+A/377/925
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper the mass of the neutron star in Vela X-1 is determined, by measuring the radial velocity curve of its B supergiant companion. The tables (appendix of the paper), which list the log of observations, and the derived radial velocities, of the blue Coude Echelle Spectrograph (CES) spectra (Table A1), the red CES spectra (Table A2), and the IUE spectra (Table A3).
- ID:
- ivo://CDS.VizieR/J/A+A/481/183
- Title:
- Radial velocity curves of V1007 Sco
- Short Name:
- J/A+A/481/183
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Having obtained new series of electronic spectra and UBV photometry of V1007 Sco, we analysed these data in an effort to check whether the observed properties of V1007 Sco indeed disagree with the prediction of stellar evolutionary models. We briefly analysed data for a few other binaries in NGC 6231, too. Spectral reductions were carried out with the MIDAS program, photometry reduced using the HEC22 program, the orbital elements were derived with the FOTEL program and the final solutions obtained with the program PHOEBE.
- ID:
- ivo://CDS.VizieR/J/A+A/647/A160
- Title:
- Radial velocity data of epsilon Cyg
- Short Name:
- J/A+A/647/A160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the Hamilton Echelle Spectrograph at Lick Observatory, we have obtained precise radial velocities of a sample of 373 G- and K-giant stars from 1999 until 2012, leading to the discovery of several single and multiple planetary systems. The radial velocities of the long-period (~53 years) spectroscopic binary epsilon Cyg (HIP 102488) are found to exhibit additional variations with a much shorter period (~291 days). This signature is not perfectly regular, as its period and amplitude seem to change over time. We intend to improve the orbital solution of the epsilon Cyg system, and attempt to identify the cause of the nearly periodic shorter period variations, which might be due to an additional substellar companion. We use precise radial velocity measurements of the K-giant star epsilon Cyg from Lick Observatory, in combination with a large set of RVs collected more recently with the SONG telescope, as well as archival data sets.
- ID:
- ivo://CDS.VizieR/J/A+A/595/A55
- Title:
- Radial velocity data of HD 59686 A
- Short Name:
- J/A+A/595/A55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For over 12 years, we have carried out a precise radial velocity (RV) survey of a sample of 373 G- and K-giant stars using the Hamilton Echelle Spectrograph at the Lick Observatory. There are, among others, a number of multiple planetary systems in our sample as well as several planetary candidates in stellar binaries. We aim at detecting and characterizing substellar and stellar companions to the giant star HD 59686 A (HR 2877, HIP 36616). We obtained high-precision RV measurements of the star HD 59686 A. By fitting a Keplerian model to the periodic changes in the RVs, we can assess the nature of companions in the system. To distinguish between RV variations that are due to non-radial pulsation or stellar spots, we used infrared RVs taken with the CRIRES spectrograph at the Very Large Telescope. Additionally, to characterize the system in more detail, we obtained high-resolution images with LMIRCam at the Large Binocular Telescope.
- ID:
- ivo://CDS.VizieR/J/AJ/161/283
- Title:
- Radial velocity estimates of 4 stars with IGRINS
- Short Name:
- J/AJ/161/283
- Date:
- 08 Mar 2022
- Publisher:
- CDS
- Description:
- Application of the radial velocity (RV) technique in the near-infrared is valuable because of the diminished impact of stellar activity at longer wavelengths, making it particularly advantageous for the study of late-type stars but also for solar-type objects. In this paper, we present the IGRINS RV open-source python pipeline for computing infrared RV measurements from reduced spectra taken with IGRINS, an R~{lambda}/{Delta}{lambda}~45000 spectrograph with simultaneous coverage of the H-band (1.49-1.80{mu}m) and K-band (1.96-2.46{mu}m). Using a modified forward-modeling technique, we construct high-resolution telluric templates from A0 standard observations on a nightly basis to provide a source of common-path wavelength calibration while mitigating the need to mask or correct for telluric absorption. Telluric standard observations are also used to model the variations in instrumental resolution across the detector, including a yearlong period when the K-band was defocused. Without any additional instrument hardware, such as a gas cell or laser frequency comb, we are able to achieve precisions of 26.8m/s in the K-band and 31.1m/s in the H-band for narrow-line hosts. These precisions are empirically determined by a monitoring campaign of two RV standard stars, as well as the successful retrieval of planet-induced RV signals for both HD189733 and {tau}BooA; furthermore, our results affirm the presence of the Rossiter-McLaughlin effect for HD189733. The IGRINS RV pipeline extends another important science capability to IGRINS, with publicly available software designed for widespread use.
