arXiv subjects

C. Lovis

Publications and source records attributed to C. Lovis.

At least 235 records · Page 13Linked to original sources

arXiv2014

The HARPS search for southern extra-solar planets XXXV. Planetary systems and stellar activity of the M dwarfs GJ 3293, GJ 3341, and GJ 3543

Context. Planetary companions of a fixed mass induce larger amplitude reflex motions around lower-mass stars, which helps make M dwarfs excellent targets for extra-solar planet searches. State of the art velocimeters with $\sim$1m/s stability can detect very low-mass planets out to the habitable zone of these stars. Low-mass, small, planets are abundant around M dwarfs, and most known potentially habitable planets orbit one of these cool stars. Aims. Our M-dwarf radial velocity monitoring with HARPS on the ESO 3.6m telescope at La Silla observatory makes a major contribution to this sample. Methods. We present here dense radial velocity (RV) time series for three M dwarfs observed over $\sim5$ years: GJ 3293 (0.42M$_\odot$), GJ 3341 (0.47M$_\odot$), and GJ 3543 (0.45M$_\odot$). We extract those RVs through minimum $χ^2$ matching of each spectrum against a high S/N ratio stack of all observed spectra for the same star. We then vet potential orbital signals against several stellar activity indicators, to disentangle the Keplerian variations induced by planets from the spurious signals which result from rotational modulation of stellar surface inhomogeneities and from activity cycles. Results. Two Neptune-mass planets - $msin(i)=1.4\pm0.1$ and $1.3\pm0.1M_{nept}$ - orbit GJ 3293 with periods $P=30.60\pm0.02$ d and $P=123.98\pm0.38$ d, possibly together with a super-Earth - $msin(i)\sim7.9\pm1.4M_\oplus$ - with period $P=48.14\pm0.12\;d$. A super-Earth - $msin(i)\sim6.1M_\oplus$ - orbits GJ 3341 with $P=14.207\pm0.007\;d$. The RV variations of GJ 3543, on the other hand, reflect its stellar activity rather than planetary signals.

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arXiv2014

The well-aligned orbit of WASP-84b: evidence for disc migration

We report the sky-projected orbital obliquity (spin-orbit angle) of WASP-84b, a 0.70-$M_{\rm Jup}$ planet in a 8.52-day orbit around a G9V/K0V star, to be $λ= 0.3 \pm 1.7^\circ$. We obtain a true obliquity of $ψ= 14.8 \pm 8.0^\circ$ from a measurement of the inclination of the stellar spin axis with respect to the sky plane. Due to the young age and the weak tidal forcing of the system, we suggest that the orbit of WASP-84b is unlikely to have both realigned and circularised from the misaligned and/or eccentric orbit likely to have arisen from high-eccentricity migration. Therefore we conclude that the planet probably migrated via interaction with the protoplanetary disc. This would make it the first short-orbit, giant planet to have been shown to have migrated via this pathway. Further, we argue that the distribution of obliquities for planets orbiting cool stars ($T_{\rm eff}$ < 6250 K) suggests that high-eccentricity migration is an important pathway for the formation of short-orbit, giant planets.

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arXiv2014

Characterization of the Kepler-101 planetary system with HARPS-N. A hot super-Neptune with an Earth-sized low-mass companion

We report on the characterization of the Kepler-101 planetary system, thanks to a combined DE-MCMC analysis of Kepler data and forty radial velocities obtained with the HARPS-N spectrograph. This system was previously validated by Rowe et al. (2014) and is composed of a hot super-Neptune, Kepler-101b, and an Earth-sized planet, Kepler-101c. These two planets orbit the slightly evolved and metal-rich G-type star in 3.49 and 6.03 days, respectively. With mass $M_{\rm p}=51.1_{-4.7}^{+5.1}~M_{\oplus}$, radius $R_{\rm p}=5.77_{-0.79}^{+0.85}~R_{\oplus}$, and density $ρ_{\rm p}=1.45_{-0.48}^{+0.83} \rm g\;cm^{-3}$, Kepler-101b is the first fully-characterized super-Neptune, and its density suggests that heavy elements make up a significant fraction of its interior; more than $60\%$ of its total mass. Kepler-101c has a radius of $1.25_{-0.17}^{+0.19}~R_{\oplus}$, which implies the absence of any H/He envelope, but its mass could not be determined due to the relative faintness of the parent star for highly precise radial-velocity measurements ($K_{\rm p}=13.8$) and the limited number of radial velocities. The $1~σ$ upper limit, $M_{\rm p} < 3.8~M_{\oplus}$, excludes a pure iron composition with a $68.3\%$ probability. The architecture of the Kepler-101 planetary system - containing a close-in giant planet and an outer Earth-sized planet with a period ratio slightly larger than the 3:2 resonance - is certainly of interest for planet formation and evolution scenarios. This system does not follow the trend, seen by Ciardi et al. (2013), that in the majority of Kepler systems of planet pairs with at least one Neptune-size or larger planet, the larger planet has the longer period.

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arXiv2014

A global analysis of Spitzer and new HARPS data confirms the loneliness and metal-richness of GJ 436 b

Context. GJ 436b is one of the few transiting warm Neptunes for which a detailed characterisation of the atmosphere is possible, whereas its non-negligible orbital eccentricity calls for further investigation. Independent analyses of several individual datasets obtained with Spitzer have led to contradicting results attributed to the different techniques used to treat the instrumental effects. Aims. We aim at investigating these previous controversial results and developing our knowledge of the system based on the full Spitzer photometry dataset combined with new Doppler measurements obtained with the HARPS spectrograph. We also want to search for additional planets. Methods. We optimise aperture photometry techniques and the photometric deconvolution algorithm DECPHOT to improve the data reduction of the Spitzer photometry spanning wavelengths from 3-24 μm. Adding the high precision HARPS radial velocity data, we undertake a Bayesian global analysis of the system considering both instrumental and stellar effects on the flux variation. Results. We present a refined radius estimate of RP=4.10 +/- 0.16 R_Earth, mass MP=25.4 +/- 2.1 M_Earth and eccentricity e= 0.162 +/- 0.004 for GJ 436b. Our measured transit depths remain constant in time and wavelength, in disagreement with the results of previous studies. In addition, we find that the post-occultation flare-like structure at 3.6 μm that led to divergent results on the occultation depth measurement is spurious. We obtain occultation depths at 3.6, 5.8, and 8.0 μm that are shallower than in previous works, in particular at 3.6 μm. However, these depths still appear consistent with a metal-rich atmosphere depleted in methane and enhanced in CO/CO2, although perhaps less than previously thought. We find no evidence for a potential planetary companion, stellar activity, nor for a stellar spin-orbit misalignment. [ABRIDGED]

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arXiv2014

CoRoT-22 b: a validated 4.9 RE exoplanet in 10-day orbit

The CoRoT satellite has provided high-precision photometric light curves for more than 163,000 stars and found several hundreds of transiting systems compatible with a planetary scenario. If ground-based velocimetric observations are the best way to identify the actual planets among many possible configurations of eclipsing binary systems, recent transit surveys have shown that it is not always within reach of the radial-velocity detection limits. In this paper, we present a transiting exoplanet candidate discovered by CoRoT whose nature cannot be established from ground-based observations, and where extensive analyses are used to validate the planet scenario. They are based on observing constraints from radial-velocity spectroscopy, adaptive optics imaging and the CoRoT transit shape, as well as from priors on stellar populations, planet and multiple stellar systems frequency. We use the fully Bayesian approach developed in the PASTIS analysis software, and conclude that the planet scenario is at least 1400 times more probable than any other false positive scenario. The primary star is a metallic solar-like dwarf, with Ms = 1.099+-0.049 Msun and Rs = 1.136 (+0.038,-0.090) Rsun . The validated planet has a radius of Rp = 4.88 (+0.17,-0.39) RE and mass less than 49 ME. Its mean density is smaller than 2.56 g/cm^3 and orbital period is 9.7566+-0.0012 days. This object, called CoRoT-22 b, adds to a large number of validated Kepler planets. These planets do not have a proper measurement of the mass but allow statistical characterization of the exoplanet population.

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arXiv2014

Planets and Stellar Activity: Hide and Seek in the CoRoT-7 system

Since the discovery of the transiting super-Earth CoRoT-7b, several investigations have yielded different results for the number and masses of planets present in the system, mainly owing to the star's high level of activity. We re-observed CoRoT-7 in January 2012 with both HARPS and CoRoT, so that we now have the benefit of simultaneous radial-velocity and photometric data. This allows us to use the off-transit variations in the star's light curve to estimate the radial-velocity variations induced by the suppression of convective blueshift and the flux blocked by starspots. To account for activity-related effects in the radial-velocities which do not have a photometric signature, we also include an additional activity term in the radial-velocity model, which we treat as a Gaussian process with the same covariance properties (and hence the same frequency structure) as the light curve. Our model was incorporated into a Monte Carlo Markov Chain in order to make a precise determination of the orbits of CoRoT-7b and CoRoT-7c. We measure the masses of planets b and c to be 4.73 +/- 0.95 Mearth and 13.56 +/- 1.08 Mearth, respectively. The density of CoRoT-7b is (6.61 +/- 1.72)(Rp/1.58 Rearth)^(-3) g.cm^(-3), which is compatible with a rocky composition. We search for evidence of an additional planet d, identified by previous authors with a period close to 9 days. We are not able to confirm the existence of a planet with this orbital period, which is close to the second harmonic of the stellar rotation at around 7.9 days. Using Bayesian model selection we find that a model with two planets plus activity-induced variations is most favoured.

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arXiv2014

Impact of micro-telluric lines on precise radial velocities and its correction

Context: In the near future, new instruments such as ESPRESSO will arrive, allowing us to reach a precision in radial-velocity measurements on the order of 10 cm/s. At this level of precision, several noise sources that until now have been outweighed by photon noise will start to contribute significantly to the error budget. The telluric lines that are not neglected by the masks for the radial velocity computation, here called micro-telluric lines, are one such noise source. Aims: In this work we investigate the impact of micro-telluric lines in the radial velocities calculations. We also investigate how to correct the effect of these atmospheric lines on radial velocities. Methods: The work presented here follows two parallel lines. First, we calculated the impact of the micro-telluric lines by multiplying a synthetic solar-like stellar spectrum by synthetic atmospheric spectra and evaluated the effect created by the presence of the telluric lines. Then, we divided HARPS spectra by synthetic atmospheric spectra to correct for its presence on real data and calculated the radial velocity on the corrected spectra. When doing so, one considers two atmospheric models for the synthetic atmospheric spectra: the LBLRTM and TAPAS. Results: We find that the micro-telluric lines can induce an impact on the radial velocities calculation that can already be close to the current precision achieved with HARPS, and so its effect should not be neglected, especially for future instruments such as ESPRESSO. Moreover, we find that the micro-telluric lines' impact depends on factors, such as the radial velocity of the star, airmass, relative humidity, and the barycentric Earth radial velocity projected along the line of sight at the time of the observation.

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arXiv2014

The GAPS programme with HARPS-N@TNG IV: A planetary system around XO-2S

We performed an intensive radial velocity monitoring of XO-2S, the wide companion of the transiting planet-host XO-2N, using HARPS-N at TNG in the framework of the GAPS programme. The radial velocity measurements indicate the presence of a new planetary system formed by a planet that is slightly more massive than Jupiter at 0.48 au and a Saturn-mass planet at 0.13 au. Both planetary orbits are moderately eccentric and were found to be dynamically stable. There are also indications of a long-term trend in the radial velocities. This is the first confirmed case of a wide binary whose components both host planets, one of which is transiting, which makes the XO-2 system a unique laboratory for understanding the diversity of planetary systems.

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arXiv2014

Transiting exoplanets from the CoRoT space mission: XXVI. CoRoT-24: A transiting multi-planet system

We present the discovery of a candidate multiply-transiting system, the first one found in the CoRoT mission. Two transit-like features with periods of 5.11 and 11.76d are detected in the CoRoT light curve, around a main sequence K1V star of r=15.1. If the features are due to transiting planets around the same star, these would correspond to objects of 3.7$\pm$0.4 and 5.0$\pm$0.5 R_earth respectively. Several radial velocities serve to provide an upper limit of 5.7 M_earth for the 5.11~d signal, and to tentatively measure a mass of 28$^{+11}_{-11}$ M_earth for the object transiting with a 11.76~d period. These measurements imply low density objects, with a significant gaseous envelope. The detailed analysis of the photometric and spectroscopic data serve to estimate the probability that the observations are caused by transiting Neptune-sized planets as $>$26$\times$ higher than a blend scenario involving only one transiting planet, and $>$900$\times$ higher than a scenario involving two blends and no planets. The radial velocities show a long term modulation that might be attributed to a 1.5 M_jup planet orbiting at 1.8~A.U. from the host, but more data are required to determine the precise orbital parameters of this companion.

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arXiv2014

The HARPS search for southern extra-solar planets XXXV. The interesting case of HD41248: stellar activity, no planets?

The search for planets orbiting metal-poor stars is of uttermost importance for our understanding of the planet formation models. However, no dedicated searches have been conducted so far for very low mass planets orbiting such objects. Only a few cases of low mass planets orbiting metal-poor stars are thus known. Amongst these, HD41248 is a metal-poor, solar-type star on which a resonant pair of super-Earth like planets has In the present paper we present a new planet search program that is using the HARPS spectrograph to search for Neptunes and Super-Earths orbiting a sample of metal-poor FGK dwarfs. We then present a detailed analysis of an additional 162 radial velocity measurements of HD41248, obtained within this program, with the goal of confirming the existence of the proposed planetary system. We analyzed the precise radial velocities, obtained with the HARPS spectrograph, together with several stellar activity diagnostics and line profile indicators. A careful analysis shows no evidence for the planetary system previously announced. One of the signals, with a period of about 25 days, is shown to be related to the rotational period of the star, and is clearly seen in some of the activity proxies. The remaining signal (P~18 days) could not be convincingly retrieved in the new data set. We discuss possible causes for the complex (evolving) signals observed in the data of HD41248, proposing that they may be explained by the appearance and disappearance of active regions on the surface of a star with strong differential rotation, or by a combination of the sparse data sampling and active region evolution.

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arXiv2014

Transit confirmation and improved stellar and planet parameters for the super-Earth HD 97658 b and its host star

Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition. We present here the confirmation, based on Spitzer transit observations, that the super-Earth HD 97658 b transits its host star. HD 97658 is a low-mass ($M_*=0.77\pm0.05\,M_{\odot}$) K1 dwarf, as determined from the Hipparcos parallax and stellar evolution modeling. To constrain the planet parameters, we carry out Bayesian global analyses of Keck-HIRES radial velocities, and MOST and Spitzer photometry. HD 97658 b is a massive ($M_P=7.55^{+0.83}_{-0.79} M_{\oplus}$) and large ($R_{P} = 2.247^{+0.098}_{-0.095} R_{\oplus}$ at 4.5 $μ$m) super-Earth. We investigate the possible internal compositions for HD 97658 b. Our results indicate a large rocky component, by at least 60% by mass, and very little H-He components, at most 2% by mass. We also discuss how future asteroseismic observations can improve the knowledge of the HD 97658 system, in particular by constraining its age. Orbiting a bright host star, HD 97658 b will be a key target for coming space missions TESS, CHEOPS, PLATO, and also JWST, to characterize thoroughly its structure and atmosphere.

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arXiv2014

ESPRESSO: The next European exoplanet hunter

The acronym ESPRESSO stems for Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations; this instrument will be the next VLT high resolution spectrograph. The spectrograph will be installed at the Combined-Coudé Laboratory of the VLT and linked to the four 8.2 m Unit Telescopes (UT) through four optical Coudé trains. ESPRESSO will combine efficiency and extreme spectroscopic precision. ESPRESSO is foreseen to achieve a gain of two magnitudes with respect to its predecessor HARPS, and to improve the instrumental radial-velocity precision to reach the 10 cm/s level. It can be operated either with a single UT or with up to four UTs, enabling an additional gain in the latter mode. The incoherent combination of four telescopes and the extreme precision requirements called for many innovative design solutions while ensuring the technical heritage of the successful HARPS experience. ESPRESSO will allow to explore new frontiers in most domains of astrophysics that require precision and sensitivity. The main scientific drivers are the search and characterization of rocky exoplanets in the habitable zone of quiet, nearby G to M-dwarfs and the analysis of the variability of fundamental physical constants. The project passed the final design review in May 2013 and entered the manufacturing phase. ESPRESSO will be installed at the Paranal Observatory in 2016 and its operation is planned to start by the end of the same year.

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arXiv2014

Three planetary companions around M67 stars

For the past six years we have carried out a search for massive planets around main sequence and evolved stars in the open cluster (OC) M67, using radial velocity (RV) measurements obtained with HARPS at ESO (La Silla), SOPHIE at OHP and HRS at HET. Additional RV data come from CORALIE at the Euler Swiss Telescope. We aim to perform a long-term study on giant planet formation in open clusters and determine how it depends on stellar mass and chemical composition. We report the detection of three new extrasolar planets: two in orbit around the two G dwarfs YBP1194 and YBP1514, and one around the evolved star S364. The orbital solution for YBP1194 yields a period of 6.9 days, an eccentricity of 0.24, and a minimum mass of 0.34 Mj. YBP1514 shows periodic RV variations of 5.1 days, a minimum mass of 0.40 Mj, and an eccentricity of 0.39. The best Keplerian solution for S364 yields a period of 121.7 days, an eccentricity of 0.35 and a minimum mass of 1.54 Mj. An analysis of H_alpha core flux measurements as well as of the line bisectors spans revealed no correlation with the RV periods, indicating that the RV variations are best explained by the presence of a planetary companion. Remarkably, YBP1194 is one of the best solar twins identified so far, and YBP1194b is the first planet found around a solar twin that belongs to a stellar cluster. In contrast with early reports and in agreement with recent findings, our results show that massive planets around stars of open clusters are as frequent as those around field stars.

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arXiv2013

On the long-term correlation between the flux in the Ca II H & K and Halpha lines for FGK stars

The re-emission in the cores of the Ca II H & K and H$α$ lines, are well known proxies of stellar activity. However, these activity indices probe different activity phenomena, the first being more sensitive to plage variation, while the other one being more sensitive to filaments. In this paper we study the long-term correlation between $\log R'_{HK}$ and $\log I_{Hα}$, two indices based on the Ca II H & K and H$α$ lines respectively, for a sample of 271 FGK stars using measurements obtained over a $\sim$9 year time span. Because stellar activity is one of the main obstacles to the detection of low-mass and long-period planets, understanding further this activity index correlation can give us some hints about the optimal target to focus on, and ways to correct for these activity effects. We found a great variety of long-term correlations between $\log R'_{HK}$ and $\log I_{Hα}$. Around 20% of our sample has strong positive correlation between the indices while about 3% show strong negative correlation. These fractions are compatible with those found for the case of early-M dwarfs. Stars exhibiting a positive correlation have a tendency to be more active when compared to the median of the sample, while stars showing a negative correlation are more present among higher metallicity stars. There is also a tendency for the positively correlated stars to be more present among the coolest stars, a result which is probably due to the activity level effect on the correlation. Activity level and metallicity seem therefore to be playing a role on the correlation between $\log R'_{HK}$ and $\log I_{Hα}$. Possible explanations based on the influence of filaments for the diversity in the correlations between these indices are discussed in this paper.

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arXiv2013

A Community Science Case for E-ELT HIRES

Building on the experience of the high-resolution community with the suite of VLT high-resolution spectrographs, which has been tremendously successful, we outline here the (science) case for a high-fidelity, high-resolution spectrograph with wide wavelength coverage at the E-ELT. Flagship science drivers include: the study of exo-planetary atmospheres with the prospect of the detection of signatures of life on rocky planets; the chemical composition of planetary debris on the surface of white dwarfs; the spectroscopic study of protoplanetary and proto-stellar disks; the extension of Galactic archaeology to the Local Group and beyond; spectroscopic studies of the evolution of galaxies with samples that, unlike now, are no longer restricted to strongly star forming and/or very massive galaxies; the unraveling of the complex roles of stellar and AGN feedback; the study of the chemical signatures imprinted by population III stars on the IGM during the epoch of reionization; the exciting possibility of paradigm-changing contributions to fundamental physics. The requirements of these science cases can be met by a stable instrument with a spectral resolution of R~100,000 and broad, simultaneous spectral coverage extending from 370nm to 2500nm. Most science cases do not require spatially resolved information, and can be pursued in seeing-limited mode, although some of them would benefit by the E-ELT diffraction limited resolution. Some multiplexing would also be beneficial for some of the science cases. (Abridged)

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arXiv2013

Line-profile variations in radial-velocity measurements: Two alternative indicators for planetary searches

Aims. We introduce two methods to identify false-positive planetary signals in the context of radial-velocity exoplanet searches. The first is the bi-Gaussian cross-correlation function fitting, and the second is the measurement of asymmetry in radial-velocity spectral line information content, Vasy. Methods. We make a systematic analysis of the most used common line profile diagnosis, Bisector Inverse Slope and Velocity Span, along with the two proposed ones. We evaluate all these diagnosis methods following a set of well-defined common criteria and using both simulated and real data. We apply them to simulated cross-correlation functions created with the program SOAP and which are affected by the presence of stellar spots, and to real cross-correlation functions, calculated from HARPS spectra, for stars with a signal originating both in activity and created by a planet. Results. We demonstrate that the bi-Gaussian method allows a more precise characterization of the deformation of line profiles than the standard bisector inverse slope. The calculation of the deformation indicator is simpler and its interpretation more straightforward. More importantly, its amplitude can be up to 30% larger than that of the bisector span, allowing the detection of smaller-amplitude correlations with radial-velocity variations. However, a particular parametrization of the bisector inverse slope is shown to be more efficient on high-signal-to-noise data than both the standard bisector and the bi-Gaussian. The results of the Vasy method show that this indicator is more effective than any of the previous ones, being correlated with the radial-velocity with more significance for signals resulting from a line deformation. Moreover, it provides a qualitative advantage over the bisector, showing significant correlations with RV for active stars for which bisector analysis is inconclusive. (abridged)

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arXiv2013

The HARPS search for southern extra-solar planets. XXXIV. A planetary system around the nearby M dwarf GJ163, with a super-Earth possibly in the habitable zone

The meter-per-second precision achieved by today velocimeters enables the search for 1-10 M_Earth planets in the habitable zone of cool stars. This paper reports on the detection of 3 planets orbiting GJ163 (HIP19394), a M3 dwarf monitored by our ESO/HARPS search for planets. We made use of the HARPS spectrograph to collect 150 radial velocities of GJ163 over a period of 8 years. We searched the RV time series for coherent signals and found 5 distinct periodic variabilities. We investigated the stellar activity and casted doubts on the planetary interpretation for 2 signals. Before more data can be acquired we concluded that at least 3 planets are orbiting GJ163. They have orbital periods of P_b=8.632+-0.002, P_c=25.63+-0.03 and P_d=604+-8 days and minimum masses msini = 10.6+-0.6, 6.8+-0.9, and 29+-3 M_Earth, respectively. We hold our interpretations for the 2 additional signals with periods P_(e)=19.4 and P_(f)=108 days. The inner pair presents an orbital period ratio of 2.97, but a dynamical analysis of the system shows that it lays outside the 3:1 mean motion resonance. GJ163c, in particular, is a super-Earth with an equilibrium temperature of T_eq = (302+-10) (1-A)^(1/4) K and may lie in the so called habitable zone for albedo values (A=0.34-0.89) moderately higher than that of Earth (A_Earth=0.2-0.3).

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arXiv2013

The GAPS programme with HARPS-N at TNG. I: Observations of the Rossiter-McLaughlin effect and characterisation of the transiting system Qatar-1

A long-term multi-purpose observational programme has started with HARPS-N@TNG aimed to characterise the global architectural properties of exoplanetary systems. In this first paper we fully characterise the transiting system Qatar-1. We exploit HARPS-N high-precision radial velocity measurements obtained during a transit to measure the Rossiter-McLaughlin effect in the Qatar-1 system, and out-of-transit measurements to redetermine the spectroscopic orbit. New photometric transit light-curves are analysed and a spectroscopic characterisation of the host star atmospheric parameters is performed based on various methods (line equivalent width ratios, spectral synthesis, spectral energy distribution). We achieved a significant improvement in the accuracy of the orbital parameters and derived the spin-orbit alignment of the system; this information, combined with the spectroscopic determination of the host star properties, allows us to derive the fundamental physical parameters for star and planet (masses and radii). The orbital solution for the Qatar-1 system is consistent with a circular orbit and the system presents a sky-projected obliquity of lambda = -8.4+-7.1 deg. The planet, with a mass of 1.33+-0.05 M_J, is found to be significantly more massive than previously reported. The host star is confirmed to be metal-rich ([Fe/H]= 0.20+-0.10) and slowly rotating (vsinI = 1.7+-0.3 km/s), though moderately active, as indicated by strong chromospheric emission in the Ca II H&K line cores (logR'_HK about -4.60). The system is well aligned and fits well within the general lambda vs Teff trend. We definitely rule out any significant orbital eccentricity. The evolutionary status of the system is inferred based on gyrochronology, and the present orbital configuration and timescale for orbital decay are discussed in terms of star-planet tidal interactions.

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