- ID:
- ivo://CDS.VizieR/J/A+A/546/A27
- Title:
- Radial velocity and photometry for GJ3470
- Short Name:
- J/A+A/546/A27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the discovery of GJ 3470b, a transiting hot Uranus of mass m_p_=14.0+/-1.8M_{earth}_, radius R_p_=4.2+/-0.6R_{earth}_ and period P=3.3371+/-0.0002-day. Its host star is a nearby (d=25.2+/-2.9pc) M1.5 dwarf of mass M_star_=0.54+/-0.07M_{sun}_ and radius R_star_=0.50+/-0.06R_{sun}_. The detection was made during a radial-velocity campaign with Harps that focused on the search for short-period planets orbiting M dwarfs. Once the planet was discovered and the transit-search window narrowed to about 10% of an orbital period, a photometric search started with Trappist and quickly detected the ingress of the planet. Additional observations with Trappist, EulerCam and Nites definitely confirmed the transiting nature of GJ3470b and allowed the determination of its true mass and radius. The star's visible or infrared brightness (Vmag=12.3, Kmag=8.0), together with a large eclipse depth D=0.57+/-0.05%, ranks GJ 3470 b among the most suitable planets for follow-up characterizations.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/509/A24
- Title:
- Radial velocity curve of {gamma}^1^ Leo
- Short Name:
- J/A+A/509/A24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Our primary goal is to search for planets around intermediate mass stars. We are also interested in studying the nature of radial velocity (RV) variations of K giant stars. We selected about 55 early K giant (K0-K4) stars brighter than fifth magnitude that were observed using BOES, a high resolution spectrograph attached to the 1.8m telescope at BOAO (Bohyunsan Optical Astronomy Observatory). BOES is equipped with I_2_ absorption cell for high precision RV measurements. We detected a periodic radial velocity variations in the K0 III star gamma1 Leo with a period of P=429-days. An orbital fit of the observed RVs yields a period of P=429-days, a semi-amplitude of K=208m/s, and an eccentricity of e=0.14. To investigate the nature of the RV variations, we analyzed the photometric, Ca II {lambda} 8662 equivalent width, and line-bisector variations of gamma1 Leo. We conclude that the detected RV variations can be best explained by a planetary companion with an estimated mass of msini=8.78M_{Jupiter}_ and a semi-major axis of a=1.19AU, assuming a stellar mass of 1.23M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/519/A10
- Title:
- Radial velocity curve of HD 202206
- Short Name:
- J/A+A/519/A10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Long-term, precise Doppler measurements with the CORALIE spectrograph have revealed the presence of two massive companions to the solar-type star HD 202206. Although the three-body fit of the system is unstable, it was shown that a 5:1 mean motion resonance exists close to the best fit, where the system is stable. It was also hinted that stable solutions with a wide range of mutual inclinations and low O-C were possible. We present here an extensive dynamical study of the HD 202206 system, aiming at constraining the inclinations of the two known companions, from which we derive possible value ranges for the companion masses.
- 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/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.
- 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/A+A/496/527
- Title:
- Radial velocity curves of HD 47186 and HD 181433
- Short Name:
- J/A+A/496/527
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This Letter reports on the detection of two new multiple planet systems around solar-like stars HD 47186 and HD 181433. The first system includes a hot Neptune of 22.78M_{Earth}_ at 4.08-days period and a Saturn of 0.35M_{Jup}_ at 3.7-years period. The second system includes a Super-Earth of 7.5M_{Earth}_ at 9.4-days period, a 0.64M_{Jup}_ at 2.6-years period as well as a third companion of 0.54M_{Jup}_ with a period of about 6 years. These detections increase to 20 the number of close-in low-mass exoplanets (below 0.1M_Jup_) and strengthen the fact that 80% of these planets are in a multiple planetary systems.
- ID:
- ivo://CDS.VizieR/J/A+A/566/A113
- Title:
- Radial velocity curves of HIP105854
- Short Name:
- J/A+A/566/A113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We are conducting a radial velocity survey called EXPRESS (EXoPlanets aRound Evolved StarS) of a sample of 166 giant stars aimed at studying the population of close-in planets and how their orbital properties are influenced by the host star evolution. We present precision radial velocity measurements of the giant star HIP 105854, which have revealed the presence of a massive giant planet in a 184-days orbit.
- 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/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.