- ID:
- ivo://CDS.VizieR/J/AJ/153/138
- Title:
- Radial velocity curve of 51 Peg
- Short Name:
- J/AJ/153/138
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the detection of water absorption features in the day side spectrum of the first-known hot Jupiter, 51 Peg b, confirming the star-planet system to be a double-lined spectroscopic binary. We use high-resolution (R{approx}100000), 3.2{mu}m spectra taken with CRIRES/VLT to trace the radial-velocity shift of the water features in the planet's day side atmosphere during 4 hr of its 4.23 day orbit after superior conjunction. We detect the signature of molecular absorption by water at a significance of 5.6{sigma} at a systemic velocity of V_sys_=-33+/-2km/s, coincident with the 51 Peg host star, with a corresponding orbital velocity K_P_=133_-3.5_^+4.3^km/s. This translates directly to a planet mass of M_p_=0.476_-0.031_^+0.032^M_J_, placing it at the transition boundary between Jovian and Neptunian worlds. We determine upper and lower limits on the orbital inclination of the system of 70{deg}<i<82.2{deg}. We also provide an updated orbital solution for 51 Peg b, using an extensive set of 639 stellar radial velocities measured between 1994 and 2013, finding no significant evidence of an eccentric orbit. We find no evidence of significant absorption or emission from other major carbon-bearing molecules of the planet, including methane and carbon dioxide. The atmosphere is non-inverted in the temperature-pressure region probed by these observations. The deepest absorption lines reach an observed relative contrast of 0.9*10^-3^ with respect to the host star continuum flux at an angular separation of 3 milliarcseconds. This work is consistent with a previous tentative report of K-band molecular absorption for 51 Peg b by Brogi et al.
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- ID:
- ivo://CDS.VizieR/J/A+A/533/A90
- Title:
- Radial velocity curves of HD 132563
- Short Name:
- J/A+A/533/A90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of our radial velocity planet-search survey performed with SARG at TNG, we monitored the components of HD 132563 for ten years. It is a binary system formed by two rather similar solar type stars with a projected separation of 4.1arcsec, which corresponds to 400AU at the distance of 96 pc. The two components are moderately metal-poor and the age of the system is about 5Gyr. We detected RV variations of HD 132563B with period of 1544 days and semi-amplitude of 26m/s. From the star characteristics and line profile measurements, we infer their Keplerian origin. Therefore HD 132563B turns out to host a planet with a projected mass msini=1.49M_Jup_ at 2.6AU with a moderately eccentric orbit (e=0.22). The planet around HD 132563B is one of the few that are known in triple stellar systems, as we found that the primary HD 132563A is itself a spectroscopic binary with a period longer than 15 years and an eccentricity higher than 0.65. The spectroscopic component was not detected in adaptive-optics images taken with AdOpt@TNG, since it expected at a projected separation that was smaller than 0.2 arcsec at the time of our observations. A small excess in K band difference between the components with respect to the difference in V band is compatible with a companion of about 0.55M_{sun}_. A preliminary statistical analysis of the occurrence of planets in triple systems indicate a similar frequency of planets around the isolated component in a triple system, components of wide binaries and single stars. There is no significant iron abundance difference between the components. The lack of stars in binary systems and open clusters showing strong enhancements of iron abundance, comparable to the typical metallicity difference between stars with and without giant planets, agrees with the idea that accretion of planetary material producing iron abundance anomalies larger than 0.1dex is rare.
- 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/A+A/573/L5
- Title:
- Radial velocity data of Kepler-432
- Short Name:
- J/A+A/573/L5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the first disclosure of the planetary nature of Kepler-432 b (aka Kepler object of interest KOI-1299.01). We accurately constrained its mass and eccentricity by high-precision radial velocity measurements obtained with the CAFE spectrograph at the CAHA 2.2-m telescope. By a simultaneous fit of these new data and Kepler photometry, we found that KOI-1299 b is a dense transiting exoplanet, having a mass of Mp=4.87+/-0.48M_Jup_ and radius of Rp=1.120+/-0.036R_Jup_. The planet revolves around a K giant star, ascending the red giant branch, every 52.5d, moving on a highly eccentric orbit with e=0.535+/-0.030. By analysing two NIR high-resolution images, we found that a star occurs at 1:100 from Kepler-432, but it is too faint to cause significant effects on the transit depth. Together with Kepler-56 and Kepler-91, KOI-1299 occupies an almost-desert region of parameter space, which is important to constrain the evolutionary processes of planetary systems.
- ID:
- ivo://CDS.VizieR/J/A+A/593/A5
- Title:
- Radial velocity fitting challenge dataset
- Short Name:
- J/A+A/593/A5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Stellar signals are the main limitation for precise radial-velocity (RV) measurements. These signals arise from the photosphere of the stars. The m/s perturbation created by these signals prevents the detection and mass characterization of small-mass planetary candidates such as Earth-twins. Several methods have been proposed to mitigate stellar signals in RV measurements. However, without precisely knowing the stellar and planetary signals in real observations, it is extremely difficult to test the efficiency of these methods. The goal of the RV fitting challenge is to generate simulated RV data including stellar and planetary signals and to perform a blind test within the community to test the efficiency of the different methods proposed to recover planetary signals despite stellar signals. In this first paper, we describe the simulation used to model the measurements of the RV fitting challenge. Each simulated planetary system includes the signals from instrumental noise, stellar oscillations, granulation, supergranulation, stellar activity, and observed and simulated planetary systems. In addition to RV variations, this simulation also models the effects of instrumental noise and stellar signals on activity observables obtained by HARPS-type high-resolution spectrographs, that is, the calcium activity index log(R'HK),and the bisector span and full width at half maximum of the cross-correlation function. We publish the 15 systems used for the RV fitting challenge including the details about the planetary systems that were injected into each of them.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A142
- Title:
- Radial velocity for GJ 1132
- Short Name:
- J/A+A/618/A142
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The source GJ1132 is a nearby red dwarf known to host a transiting Earth-size planet. After its initial detection, we pursued an intense follow-up with the HARPS velocimeter. We now confirm the detection of GJ1132b with radial velocities alone. We refined its orbital parameters, and in particular, its mass (m_b_= 1.66+/-0.23M_{sun}_), density ({rho}_b_=6.3+/-1.3g/cm^3^), and eccentricity (e_b_<0.22; 95%). We also detected at least one more planet in the system. GJ1132c is a super-Earth with period P_c_=8.93+/-0.01-days and minimum mass m_c_sini_c_=2.64+/-0.44M_{sun}_. Receiving about 1.9 times more flux than Earth in our solar system, its equilibrium temperature is that of a temperate planet (T_eq_=230-300K for albedos A=0.75-0.00), which places GJ1132c near the inner edge of the so-called habitable zone. Despite an a priori favorable orientation for the system, Spitzer observations reject most transit configurations, leaving a posterior probability <1% that GJ11 32c transits. GJ1132(d) is a third signal with period P_d_=177+/-5-days attributed to either a planet candidate with minimum mass m_d_sini_d_=8.4^+1.7^_-2.5_M_{sun}_ or stellar activity. Its Doppler signal is the most powerful in our HARPS time series but appears on a timescale where either the stellar rotation or a magnetic cycle are viable alternatives to the planet hypothesis. On the one hand, the period is different than that measured for the stellar rotation (~125-days), and a Bayesian statistical analysis we performed with a Markov chain Monte Carlo and Gaussian processes demonstrates that the signal is better described by a Keplerian function than by correlated noise. On the other hand, periodograms of spectral indices sensitive to stellar activity show power excess at similar periods to that of this third signal, and radial velocity shifts induced by stellar activity can also match a Keplerian function. We therefore prefer to leave the status of GJ1132(d) undecided.
- ID:
- ivo://CDS.VizieR/J/A+A/613/A25
- Title:
- Radial velocity for Ross 128
- Short Name:
- J/A+A/613/A25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- After that a new technique combining high-contrast imaging and high-dispersion spectroscopy successfully detected the atmosphere of a giant planet, it soon became contemplated as one of the most promising avenues to study the atmosphere of Earth-size worlds. With the forthcoming ELTs, it shall gain the angular resolution and sensitivity to even detect O2 in the atmosphere of planets orbiting red dwarfs. This is a strong motivation to make the census of planets around cool stars which habitable zones can be resolved by ELTs, i.e. for M dwarfs within ~5-parsecs. In that context, our HARPS survey is already a major contributor to that sample of nearby planets. Here we report on our radial-velocity observations of Ross 128 (Proxima Virginis, GJ447, HIP 57548), a M4 dwarf just 3.4-parsec away from our Sun. We detect it is host of an exo-Earth with a projected mass m*sini=1.35M_{sun}_ and an orbital period of 9.9-days. Ross 128 b receives ~1.38 as much flux as Earth from the Sun and has an equilibrium temperature between 269K (resp. 213K) for an Earth-like (resp. Venus-like) albedo. According to recent studies, it is located at the inner edge of the so called habitable zone. An 80-day long light curve performed by K2 during campaign C01 excludes Ross 128 b is a transiting planet. Together with ASAS photometry and other activity indices, it argues for a long rotational period and a weak activity which, in the context of habitability, gives a high merit to the detection. Today, Ross 128 b is the second closest known exo-Earth after Proxima Centauri b (1.3 parsec) and the closest known temperate planet around a quiet star. At maximum elongation, the planet-star angular separation of 15 milli-arcsec will be resolved by the ELT (>3{lambda}/D) in all optical bands of O_2_.
- ID:
- ivo://CDS.VizieR/J/AJ/162/117
- Title:
- Radial velocity for 19 RR Lyrae
- Short Name:
- J/AJ/162/117
- Date:
- 21 Mar 2022 00:54:18
- Publisher:
- CDS
- Description:
- We report 272 radial velocities for 19 RR-Lyrae variables. For most of the stars we have radial velocities for the complete pulsation cycle. These data are used to determine robust center-of-mass radial velocities that have been compared to values from the literature in a search for evidence of binary systems. Center-of-mass velocities were determined for each star using Fourier Series and template fits to the radial velocities. Our center-of-mass velocities have uncertainties from {+/-}0.16km/s to {+/-}2.5km/s, with a mean uncertainty of {+/-}0.92km/s. We combined our center-of-mass velocities with values from the literature to look for deviations from the mean center-of-mass velocity of each star. Fifteen RR-Lyrae show no evidence of binary motion (BK And, CI And, Z CVn, DM Cyg, BK Dra, RR Gem, XX Hya, SZ Leo, BX Leo, TT Lyn, CN Lyr, TU Per, U Tri, RV UMa, and AV Vir). In most cases this conclusion is reached due to the sporadic sampling of the center-of-mass velocities over time. Three RR Lyrae show suspicious variation in the center-of-mass velocities that may indicate binary motion but do not prove it (SS Leo, ST Leo, and AO Peg). TU UMa was observed by us near a predicted periastron passage (at 0.14 in orbital phase) but the absence of additional center-of-mass velocities near periastron makes the binary detection, based on radial velocities alone, uncertain. Two stars in our sample show H{gamma} emission in phases 0.9-1.0: SS Leo and TU UMa.
- ID:
- ivo://CDS.VizieR/J/A+A/551/A73
- Title:
- Radial Velocity for WASP-54b, WASP-56b and WASP-57b
- Short Name:
- J/A+A/551/A73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present three newly discovered sub-Jupiter mass planets from the SuperWASP survey: WASP-54b is a heavily bloated planet, and orbits a F9 star, evolving off the main sequence, every 3.69 days. WASP-56b and WASP-57b orbit main sequence stars of spectral type G6 every 4.67 and 2.84 days, respectively. WASP-56b and WASP-57b show no radius anomaly and a high density implying a large core of heavy elements; possibly as high as 50M_Earth_ in the case of WASP-57b. We present the Radial Velocity and line bisector span measurements for the transiting planet host stars WASP-54, WASP-56 and WASP-57.
- ID:
- ivo://CDS.VizieR/J/A+A/374/227
- Title:
- Radial velocity in multiple systems
- Short Name:
- J/A+A/374/227
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New close sub-systems are reported and studied in eight visual multiple systems. Elements of one double-lined and eight single-lined spectroscopic orbits are given. Magnitudes, colors, spectral types, masses of individual components are estimated by combining all available data. The visual secondary component of the young binary HD 27638 is a double-lined pair of G-type dwarfs on a 17-day orbit with an unseen but massive (>1.2M_{sun}_) spectroscopic tertiary on an 8-year orbit. The invisible secondary of HD 28271A is also massive, but it is not seen probably owing to a high luminosity of the primary - an F7 star with fast axial rotation and active chromosphere which evolves off the Main Sequence. Two additional companions are found in the visual triple system HD 179484.
