- ID:
- ivo://CDS.VizieR/J/A+A/618/A115
- Title:
- HD 147379 radial velocities
- Short Name:
- J/A+A/618/A115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Despite their activity, low-mass stars are of particular importance for the search of exoplanets by the means of Doppler spectroscopy, as planets with lower masses become detectable. We report on the discovery of a planetary companion around HD 180617, a bright J=5.58mag, low-mass M=0.45_{sun}_ star of spectral type M2.5 V. The star, located at a distance of 5.9pc, is the primary of the high proper motion binary system containing vB 10, a star with one of the lowest masses known in most of the twentieth century. Our analysis is based on new radial velocity (RV) measurements made at red-optical wavelengths provided by the high-precision spectrograph CARMENES, which was designed to carry out a survey for Earth-like planets around M dwarfs. The available CARMENES data are augmented by archival Doppler measurements from HIRES and HARPS. Altogether, the RVs span more than 16 years. The modeling of the RV variations, with a semi-amplitude of K=2.85-0.25/+0.16m/s yields a Neptune-like planet with a minimum mass of 12.2-1.4/+1.0M_{Earth}_ on a 105.90-0.10/+0.09d circumprimary orbit, which is partly located in the host star's habitable zone. The analysis of time series of common activity indicators does not show any dependence on the detected RV signal. The discovery of HD 180617 b not only adds information to a currently hardly filled region of the mass-period diagram of exoplanets around M dwarfs, but the investigated system becomes the third known binary consisting of M dwarfs and hosting an exoplanet in an S-type configuration. Its proximity makes it an attractive candidate for future studies.
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- ID:
- ivo://CDS.VizieR/J/A+A/479/271
- Title:
- HD 196885 radial velocities
- Short Name:
- J/A+A/479/271
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to significantly increase the number of detected extra-solar planets in a magnitude-limited sample to improve our knowledge of their orbital element distributions and thus obtain better constraints for planet-formation models. Radial-velocity data were taken at Haute-Provence Observatory (OHP, France) with the ELODIE echelle spectrograph. We report the presence of a planet orbiting HD 196885A, with an orbital period of 1349 days. This star was previously suggested to host a 386-day planet, but we cannot confirm its existence. We also detect the presence of a stellar companion, HD 196885B, and give some constraints on its orbit.
- ID:
- ivo://CDS.VizieR/J/A+A/635/A13
- Title:
- HD41248 Radial velocities and activity indicators
- Short Name:
- J/A+A/635/A13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Twenty-four years after the first exoplanet discoveries, the radial-velocity (RV) method is still one of the most productive techniques to detect and confirm exoplanets. But stellar magnetic activity can induce RV variations large enough to make it difficult to disentangle planet signals from the stellar noise. In this context, HD 41248 is an interesting planet-host candidate, with RV observations plagued by activity-induced signals. We report on ESPRESSO observations of HD 41248 and analyse them together with previous observations from HARPS, with the goal of evaluating the presence of orbiting planets. Using different noise models within a general Bayesian framework designed for planet detection in RV data, we test the significance of the various signals present in the HD 41248 data set. We use Gaussian processes as well as a first-order moving average component to try to correct for activity-induced signals. At the same time, we analyse photometry from the TESS mission, searching for transits and rotational modulation in the lightcurve. The number of significantly detected Keplerian signals depends on the noise model employed, ranging from 0 with the Gaussian process model to 3 with a white noise model. We find that the Gaussian process alone can explain the RV data and allows for the stellar rotation period and active region evolution timescale to be constrained. The rotation period estimated from the RVs agrees with the value determined from the TESS lightcurve. Based on the currently available data, we conclude that the RV variations of HD 41248 can be explained by stellar activity (using the Gaussian process model) in line with the evidence from activity indicators and the TESS photometry.
- ID:
- ivo://CDS.VizieR/J/ApJ/761/46
- Title:
- HD 37605 radial velocities and photometry
- Short Name:
- J/ApJ/761/46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the radial velocity discovery of a second planetary mass companion to the K0 V star HD 37605, which was already known to host an eccentric, P~55 days Jovian planet, HD 37605b. This second planet, HD 37605c, has a period of ~7.5 years with a low eccentricity and an Msini of ~3.4M_Jup_. Our discovery was made with the nearly 8 years of radial velocity follow-up at the Hobby-Eberly Telescope and Keck Observatory, including observations made as part of the Transit Ephemeris Refinement and Monitoring Survey effort to provide precise ephemerides to long-period planets for transit follow-up. With a total of 137 radial velocity observations covering almost 8 years, we provide a good orbital solution of the HD 37605 system, and a precise transit ephemeris for HD 37605b. Our dynamic analysis reveals very minimal planet-planet interaction and an insignificant transit time variation. Using the predicted ephemeris, we performed a transit search for HD 37605b with the photometric data taken by the T12 0.8m Automatic Photoelectric Telescope (APT) and the MOST satellite. Though the APT photometry did not capture the transit window, it characterized the stellar activity of HD 37605, which is consistent of it being an old, inactive star, with a tentative rotation period of 57.67 days. The MOST photometry enabled us to report a dispositive null detection of a non-grazing transit for this planet. Within the predicted transit window, we exclude an edge-on predicted depth of 1.9% at the {Gt}10{sigma} level, and exclude any transit with an impact parameter b>0.951 at greater than 5{sigma}. We present the BOOTTRAN package for calculating Keplerian orbital parameter uncertainties via bootstrapping. We made a comparison and found consistency between our orbital fit parameters calculated by the RVLIN package and error bars by BOOTTRAN with those produced by a Bayesian analysis using MCMC.
- ID:
- ivo://CDS.VizieR/J/ApJ/754/37
- Title:
- HD 192263 radial velocities and photometry
- Short Name:
- J/ApJ/754/37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of the Transit Ephemeris Refinement and Monitoring Survey, we present new radial velocities and photometry of the HD 192263 system. Our analysis of the already available Keck-HIRES and CORALIE radial velocity measurements together with the five new Keck measurements we report in this paper results in improved orbital parameters for the system. We derive constraints on the size and phase location of the transit window for HD 192263b, a Jupiter-mass planet with a period of 24.3587+/-0.0022 days. We use 10 years of Automated Photoelectric Telescope photometry to analyze the stellar variability and search for planetary transits. We find continuing evidence of spot activity with periods near 23.4 days. The shape of the corresponding photometric variations changes over time, giving rise to not one but several Fourier peaks near this value. However, none of these frequencies coincides with the planet's orbital period and thus we find no evidence of star-planet interactions in the system. We attribute the ~23 day variability to stellar rotation. There are also indications of spot variations on longer (8 years) timescales. Finally, we use the photometric data to exclude transits for a planet with the predicted radius of 1.09R_J_, and as small as 0.79R_J_.
- ID:
- ivo://CDS.VizieR/J/AJ/132/1910
- Title:
- HD 131861 radial velocities and VRI light curves
- Short Name:
- J/AJ/132/1910
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Our red-wavelength spectroscopic observations of HD 131861, a previously known single-line multiple system, span 20 years. Now lines of two components, the short-period F5 V primary and G8 V secondary, have been detected. The inner orbit is circular with a period of 3.5507439-days, while the outer orbit of the system has a period of 1642 days or 4.496-yr and a relatively low eccentricity of 0.10. Analysis of the Hipparcos data produces a well-determined astrometric orbit for the long-period system that has an inclination of 52{deg}. Our photometric observations show shallow primary and secondary eclipses of the short-period pair, and eclipse solutions result in an inclination of 81{deg}. Thus, the long- and short-period orbits are not coplanar. The mass of the unseen third component is 0.7M_{dot}_, corresponding to a mid-K dwarf. The total mass of the system, 3.08M_{dot}_, leads to a semimajor axis of 4AU for the outer orbit. The F5 V primary is rotating more slowly than it would if it were synchronously rotating, while the G8 V secondary may be synchronously rotating. The lithium abundance of the F5 V primary is similar to the initial lithium abundance found for Population I dwarfs and so indicates no significant dilution.
- ID:
- ivo://CDS.VizieR/J/A+A/615/A19
- Title:
- HD54662 radial velocities and X-ray light curves
- Short Name:
- J/A+A/615/A19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- HD 54662 is an O-type binary star belonging to the CMa OB1 association. Due to its long-period orbit, this system is an interesting target to test the adiabatic wind shock model. The goal of this study is to improve our knowledge of the orbital and stellar parameters of HD 54662 and to analyze its X-ray emission to test the theoretical scaling of X-ray emission with orbital separation for adiabatic wind shocks. A spectral disentangling code is applied to a set of optical spectra to determine the radial velocities, as well as the individual spectra of the primary and secondary stars. The orbital solution of the system is established and the reconstructed individual spectra are analyzed by means of the CMFGEN model atmosphere code. Two X-ray spectra are fitted using a Markov Chain Monte Carlo algorithm and are compared to the emission expected from adiabatic shocks. We determine an orbital period of 2103.4 days, a surprisingly low orbital eccentricity of 0.11, and a mass ratio m_2/m_1 of 0.84. Combined with the orbital inclination inferred in a previous astrometric study, we obtain surprisingly low masses of 9.7 and 8.2M_{sun}_. From the disentangled primary and secondary spectra, we infer O6.5 spectral types for both stars with the primary being about two times brighter than the secondary. The softness of the X-ray spectra for the two observations, the very small variation of best-fitting spectral parameters and the comparison of the X-ray-to- bolometric luminosity ratio with the canonical value for O-type stars allow us to conclude that the X-ray emission from the wind interaction region is quite small and that the observed emission is rather dominated by the intrinsic emission from the stars. Computing the peculiar radial and intrinsic emission from the stars. Computing the peculiar radial and tangential velocities, we cannot confirm the runaway status previously attributed to HD 54662. We find no X-ray emission associated with the bow shock detected in the infrared. The lack of hard X-ray emission from the wind-shock region suggests that the mass-loss rates are lower than expected and/or that the pre-shock wind velocities are much lower than the terminal wind velocities. The bow shock associated with HD 54662 possibly corresponds to a wind-blown arc created by the interaction of the stellar winds with the ionized gas of the CMa OB1 association rather than by a large differential velocity between the binary and the surrounding interstellar medium.
- ID:
- ivo://CDS.VizieR/J/A+A/488/635
- Title:
- HD 203608 radial velocity
- Short Name:
- J/A+A/488/635
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We conducted a 5-night observing run with the spectrometer HARPS at the ESO 3.6-m telescope in August 2006. We selected the 4th magnitude F8V star HD 203608, a low-metallicity star of the old galactic disk. We reduced the spectra with the on-line data reduction software provided by the instrument. We developed a new statistical approach for extracting the significant peaks in the Fourier domain.
- ID:
- ivo://CDS.VizieR/J/A+A/561/A65
- Title:
- HD113337 radial velocity
- Short Name:
- J/A+A/561/A65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the frame of the search for extrasolar planets and brown dwarfs around early-type main-sequence stars, we present the detection of a giant planet around the young F-type star HD113337. We estimated the age of the system to be 150^+100^_-50_Myr. Interestingly, an IR excess attributed to a cold debris disk was previously detected on this star. The SOPHIE spectrograph on the 1.93m telescope at the Observatoire de Haute-Provence (OHP) was used to obtain ~300 spectra over 6 years. We used our SAFIR tool, dedicated to the spectra analysis of A and F stars, to derive the radial velocity variations. The data reveal a 324.0^+1.7^_-3.3_days period that we attribute to a giant planet with a minimum mass of 2.83+/-0.24MJup in an eccentric orbit with e=0.46+/-0.04. A long-term quadratic drift, that we assign to be probably of stellar origin, is superimposed to the Keplerian solution.
- ID:
- ivo://CDS.VizieR/J/ApJ/795/41
- Title:
- HD 128311 radial velocity and astrometric data
- Short Name:
- J/ApJ/795/41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used high-cadence radial velocity measurements from the Hobby-Eberly Telescope with published velocities from the Lick 3 m Shane Telescope, combined with astrometric data from the Hubble Space Telescope (HST) Fine Guidance Sensors to refine the orbital parameters of the HD 128311 system, and determine an inclination of 55.95{deg}+/-14.55{deg} and true mass of 3.789_-0.432_^+0.924^ M_JUP_ for HD 128311 c. The combined radial velocity data also reveal a short period signal which could indicate a third planet in the system with an Msin i of 0.133+/-0.005 M_JUP_or stellar phenomena. Photometry from the T12 0.8 m automatic photometric telescope at the Fairborn Observatory and HST are used to determine a photometric period close to, but not within the errors of the radial velocity signal. We performed a cross-correlation bisector analysis of the radial velocity data to look for correlations with the photometric period and found none. Dynamical integrations of the proposed system show long-term stability with the new orbital parameters of over 10 million years. Our new orbital elements do not support the claims of HD 128311 b and c being in mean motion resonance.
