- ID:
- ivo://CDS.VizieR/J/A+A/474/293
- Title:
- Radial velocities of GJ 674
- Short Name:
- J/A+A/474/293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The paper reports the discovery of a 11M_{earth}_ planet orbiting the nearby M dwarf GJ 674. The paper also shows the star has a spot on its surface. The spot modulates the radial-velocity, the photometric measurements as well as the spectroscopic indices. Here we list the radial-velocity data measured with HARPS (a high-resolution spectrograph providing high precision radial velocities), the spectroscopic indices measured on the same spectra gathered with HARPS and the photometric measurements gathered with the C2 Camera of the EULER Telescope.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/371/1140
- Title:
- Radial velocities of K0 stars
- Short Name:
- J/MNRAS/371/1140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Paper XIII (Griffin, 1986MNRAS.219...95G) of this series presented radial velocities for 406 stars in certain of the Clube Selected Areas, a set of areas systematically arranged in Galactic coordinates. We now complete the survey by providing the radial velocities, mostly obtained at the European Southern Observatory (ESO), of 625 stars in the six southernmost Areas. Each star has been measured at least twice; the mean velocities have standard errors typically of 0.2-0.3km/s. Additional observations made from Haute-Provence of many of the stars that are observable from there have helped to identify, and in some instances to characterize, the ~70 spectroscopic binaries discovered in this programme. The final results of the programme, complementing those given in table 3 of Paper XIII, are summarized in Table 12, which presents the mean velocities and velocity dispersions in the six southern Areas. It is noted that the difference between Paper XIII and this one as regards the provenance of the radial velocities has led to a small difference in zero-points, which is discussed in Section 3 and needs to be taken into account in any analysis of the combined data.
- ID:
- ivo://CDS.VizieR/J/PASP/117/1
- Title:
- Radial velocities of 166 LHS stars
- Short Name:
- J/PASP/117/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 178 radial velocity measurements for 166 late-type stars selected from the Luyten Half-Second (LHS) proper motion catalog (Cat. <I/87>). Space velocities are given for all but two of them. Most of the stars lie within 25pc of the Sun, but the list includes a handful of high-velocity transients from the halo population.
- ID:
- ivo://CDS.VizieR/J/A+A/521/A12
- Title:
- Radial velocities of nearby late-type stars
- Short Name:
- J/A+A/521/A12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Nearby late-type stars are excellent targets for seeking young objects in stellar associations and moving groups. The origin of these structures is still misunderstood, and lists of moving group members often change with time and also from author to author. Most members of these groups have been identified by means of kinematic criteria, leading to an important contamination of previous lists by old field stars. We attempt to identify unambiguous moving group members among a sample of nearby-late type stars by studying their kinematics, lithium abundance, chromospheric activity, and other age-related properties.
- ID:
- ivo://CDS.VizieR/J/A+A/498/627
- Title:
- Radial velocities of SB with M giant
- Short Name:
- J/A+A/498/627
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is a follow-up of the vast effort to collect radial velocity data for stars belonging to the Hipparcos survey. We aim at extending the orbital data available for binaries with M giant primaries. The data will be used in the companion papers of this series to (i) derive the binary frequency among M giants and compare it to that of K giants (Paper II, Frankowski et al., 2009A&A...498..479F), and (ii) analyse the eccentricity-period diagram and the mass-function distribution (Paper III, Jorissen et al., 2009A&A...498..489J). Keplerian solutions are fitted to radial-velocity data. However, for several stars, no satisfactory solution could be found, despite the fact that the radial-velocity standard deviation is larger than the instrumental error, because M giants suffer from intrinsic radial-velocity variations due to pulsations. We show that these intrinsic radial-velocity variations can be linked with both the average spectral-line width and the photometric variability. We present an extensive collection of spectroscopic orbits for M giants, with 12 new orbits, plus 17 from the literature. Moreover, to illustrate the fact that the large radial-velocity jitter present in Mira and semi-regular variables may easily be confused with orbital variations, we also present examples of pseudo-orbital variations (in S UMa, X Cnc and possibly in HD 115521, a former IAU radial-velocity standard). Because of this difficulty, M giants involving Mira variables were excluded from our monitored sample. We finally show that the majority of M giants detected as X-ray sources are actually binaries.
- ID:
- ivo://CDS.VizieR/J/ApJ/681/1254
- Title:
- Radial velocities of stars in the Galactic Center
- Short Name:
- J/ApJ/681/1254
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from K-band slit scan observations of a ~20"x20" region of the Galactic center (GC) in two separate epochs more than 5 years apart. The high-resolution (R={lamda}/{Delta}{lambda}>=14000) observations allow the most accurate radial velocity and acceleration measurements of the stars in the central parsec of the Galaxy. Detected stars can be divided into three groups based on the CO absorption band heads at ~2.2935um and the HeII lines at ~2.0581 and ~2.112, 2.113um: cool, narrow-line hot, and broad-line hot. The radial velocities of the cool, late-type stars have approximately a symmetrical distribution with its center at ~-7.8+/-10.3km/s and a standard deviation ~113.7+/-10.3km/s. Although our statistics are dominated by the brightest stars, we estimate a central black hole mass of (3.9+/-1.1)x10^6^M_{sun}_, consistent with current estimates from complete orbits of individual stars. Our surface density profile and the velocity dispersion of the late-type stars support the existence of a low-density region at the Galactic center suggested by earlier observations.
- ID:
- ivo://CDS.VizieR/J/A+A/495/959
- Title:
- Radial velocity curve of HD 189733
- Short Name:
- J/A+A/495/959
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extra-solar planet search programs require high-precision velocity measurements. They need to study how to disentangle radial-velocity variations due to Doppler motion from the noise induced by stellar activity. We monitored the active K2V star HD 189733 and its transiting planetary companion that has a 2.2-day orbital period. We used the high-resolution spectrograph SOPHIE mounted on the 1.93-m telescope at the Observatoire de Haute-Provence to obtain 55 spectra of HD 189733 over nearly two months. We refined the HD 189733b orbit parameters and put limits on the eccentricity and on a long-term velocity gradient. After subtracting the orbital motion of the planet, we compared the variability of spectroscopic activity indices to the evolution of the radial-velocity residuals and the shape of spectral lines. The radial velocity, the spectral-line profile and the activity indices measured in HeI (5875.62{AA}), Halpha (6562.81{AA}) and the CaII H&K lines (3968.47{AA} and 393 3.66{AA}) show a periodicity around the stellar rotation period and the correlations between them are consistent with a spotted stellar surface in rotation. We used such correlations to correct for the radial-velocity jitter due to stellar activity. This results in achieving high precision on the orbit parameters, with a semi-amplitude K=200.56+/-0.88m/s and a derived planet mass of M_P_=1.13+/-0.03M_{Jup}_.
- 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/614/A122
- Title:
- Radial-velocity of CARMENES M dwarfs
- Short Name:
- J/A+A/614/A122
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Previous simulations predicted the activity-induced radial-velocity (RV) variations of M dwarfs to range from ~1cm/s to ~1km/s, depending on various stellar and activity parameters. We investigate the observed relations between RVs, stellar activity, and stellar parameters of M dwarfs by analyzing CARMENES high-resolution visual-channel spectra (0.5-1um), which were taken within the CARMENES RV planet survey during its first 20 months of operation. During this time, 287 of the CARMENES- sample stars were observed at least five times. From each spectrum we derived a relative RV and a measure of chromospheric Halpha emission. In addition, we estimated the chromatic index (CRX) of each spectrum, which is a measure of the RV wavelength dependence. Despite having a median number of only 11 measurements per star, we show that the RV variations of the stars with RV scatter of >10m/s and a projected rotation velocity vsini>2km/s are caused mainly by activity. We name these stars 'active RV-loud stars' and find their occurrence to increase with spectral type: from ~3% for early-type M dwarfs (M0.0-2.5V) through ~30% for mid-type M dwarfs (M3.0-5.5V) to >50% for late-type M dwarfs (M6.0-9.0V). Their RV-scatter amplitude is found to be correlated mainly with vsini. For about half of the stars, we also find a linear RV-CRX anticorrelation, which indicates that their activity-induced RV scatter is lower at longer wavelengths. For most of them we can exclude a linear correlation between RV and Halpha emission. Our results are in agreement with simulated activity-induced RV variations in M dwarfs. The RV variations of most active RV-loud M dwarfs are likely to be caused by dark spots on their surfaces, which move in and out of view as the stars rotate.
- ID:
- ivo://CDS.VizieR/J/AJ/149/8
- Title:
- Radial velocity of southern visual multiple stars
- Short Name:
- J/AJ/149/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution spectra of visual multiple stars were taken in 2008-2009 to detect or confirm spectroscopic subsystems and to determine their orbits. Radial velocities of 93 late-type stars belonging to visual multiple systems were measured by numerical cross-correlation. We provide the individual velocities, the width, and the amplitude of the Gaussians that approximate the correlations. The new information on the multiple systems resulting from these data is discussed. We discovered double-lined binaries in HD 41742B, HD 56593C, and HD 122613AB, confirmed several other known subsystems, and constrained the existence of subsystems in some visual binaries where both components turned out to have similar velocities. The orbits of double-lined subsystems with periods of 148 and 13 days are computed for HD 104471 Aa,Ab and HD 210349 Aa,Ab, respectively. We estimate individual magnitudes and masses of the components in these triple systems and update the outer orbit of HD 104471 AB.
