arXiv subjects

A. P. Hatzes

Publications and source records attributed to A. P. Hatzes.

At least 109 records · Page 6Linked to original sources

arXiv2018

The CARMENES search for exoplanets around M dwarfs. First visual-channel radial-velocity measurements and orbital parameter updates of seven M-dwarf planetary systems

Context: The main goal of the CARMENES survey is to find Earth-mass planets around nearby M-dwarf stars. Seven M-dwarfs included in the CARMENES sample had been observed before with HIRES and HARPS and either were reported to have one short period planetary companion (GJ15A, GJ176, GJ436, GJ536 and GJ1148) or are multiple planetary systems (GJ581 and GJ876). Aims: We aim to report new precise optical radial velocity measurements for these planet hosts and test the overall capabilities of CARMENES. Methods: We combined our CARMENES precise Doppler measurements with those available from HIRES and HARPS and derived new orbital parameters for the systems. Bona-fide single planet systems are fitted with a Keplerian model. The multiple planet systems were analyzed using a self-consistent dynamical model and their best fit orbits were tested for long-term stability. Results: We confirm or provide supportive arguments for planets around all the investigated stars except for GJ15A, for which we find that the post-discovery HIRES data and our CARMENES data do not show a signal at 11.4 days. Although we cannot confirm the super-Earth planet GJ15Ab, we show evidence for a possible long-period ($P_{\rm c}$ = 7025$_{-629}^{+972}$ d) Saturn-mass ($m_{\rm c} \sin i$ = 51.8$_{-5.8}^{+5.5}M_\oplus$) planet around GJ15A. In addition, based on our CARMENES and HIRES data we discover a second planet around GJ1148, for which we estimate a period $P_{\rm c}$ = 532.6$_{-2.5}^{+4.1}$ d, eccentricity $e_{\rm c}$ = 0.34$_{-0.06}^{+0.05}$ and minimum mass $m_{\rm c} \sin i$ = 68.1$_{-2.2}^{+4.9}M_\oplus$. Conclusions: The CARMENES optical radial velocities have similar precision and overall scatter when compared to the Doppler measurements conducted with HARPS and HIRES. We conclude that CARMENES is an instrument that is up to the challenge of discovering rocky planets around low-mass stars.

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arXiv2018

Occultations from an active accretion disk in a 72 day detached post-Algol system detected by K2

Disks in binary systems can cause exotic eclipsing events. MWC 882 (BD-22 4376, EPIC 225300403) is such a disk-eclipsing system identified from observations during Campaign 11 of the K2 mission. We propose that MWC 882 is a post-Algol system with a B7 donor star of mass $0.542\pm0.053\,M_\odot$ in a 72 day period orbit around an A0 accreting star of mass $3.24\pm0.29\,M_\odot$. The $59.9\pm6.2\,R_\odot$ disk around the accreting star occults the donor star once every orbit, inducing 19 day long, 7% deep eclipses identified by K2, and subsequently found in pre-discovery ASAS and ASAS-SN observations. We coordinated a campaign of photometric and spectroscopic observations for MWC 882 to measure the dynamical masses of the components and to monitor the system during eclipse. We found the photometric eclipse to be gray to $\approx 1$%. We found the primary star exhibits spectroscopic signatures of active accretion, and observed gas absorption features from the disk during eclipse. We suggest MWC 882 initially consisted of a $\approx 3.6\,M_\odot$ donor star transferring mass via Roche lobe overflow to a $\approx 2.1\,M_\odot$ accretor in a $\approx 7$ day initial orbit. Through angular momentum conservation, the donor star is pushed outward during mass transfer to its current orbit of 72 days. The observed state of the system corresponds with the donor star having left the Red Giant Branch ~0.3 Myr ago, terminating active mass transfer. The present disk is expected to be short-lived ($10^2$ years) without an active feeding mechanism, presenting a challenge to this model.

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arXiv2018

The Radial Velocity Variability of the K-giant Gamma Draconis: Stellar Variability Masquerading as a Planet

We present precise stellar radial velocity measurements of Gamma Dra taken from 2003 to 2017. The data from 2003 to 2011 show coherent, long-lived variations with a period of 702 d. These variations are consistent with the presence of a planetary companion having m sin i = 10.7 M_Jup whose orbital properties are typical for giant planets found around evolved stars. An analysis of the Hipparcos photometry, Ca II S-index measurements, and measurements of the spectral line shapes during this time show no variations with the radial velocity of the planet which seems to "confirm"' the presence of the planet. However, radial velocity measurements taken 2011 -- 2017 seem to refute this. From 2011 to 2013 the radial velocity variations virtually disappear only to return in 2014, but with a noticeable phase shift. The total radial velocity variations are consistent either with amplitude variations on timescales of ~ 10.6 yr, or the beating effect between two periods of 666 d and 801 d. It seems unlikely that both these signals stem from a two-planet system. A simple dynamical analysis indicates that there is only a 1-2 % chance that the two-planet is stable. Rather, we suggest that this multi-periodic behavior may represent a new form of stellar variability, possibly related to oscillatory convective modes. If such intrinsic stellar variability is common around K giant stars and is attributed to planetary companions, then the planet occurrence rate among these stars may be significantly lower than thought.

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arXiv2018

K2-141 b: A 5-M$_\oplus$ super-Earth transiting a K7 V star every 6.7 hours

We report on the discovery of K2-141 b (EPIC 246393474 b), an ultra-short-period super-Earth on a 6.7-hour orbit transiting an active K7 V star based on data from K2 campaign 12. We confirmed the planet's existence and measured its mass with a series of follow-up observations: seeing-limited MuSCAT imaging, NESSI high-resolution speckle observations, and FIES and HARPS high-precision radial-velocity monitoring. K2-141 b has a mass of $5.31 \pm 0.46 $ $M_{\oplus}$ and radius of $1.54^{+0.10}_{-0.09}$ $R_{\oplus}$, yielding a mean density of $8.00_{ - 1.45 } ^ { + 1.83 }$ $\mathrm{g\,cm^{-3}}$ and suggesting a rocky-iron composition. Models indicate that iron cannot exceed $\sim$70 % of the total mass. With an orbital period of only 6.7 hours, K2-141 b is the shortest-period planet known to date with a precisely determined mass.

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arXiv2017

The CARMENES search for exoplanets around M dwarfs - HD 147379b: A nearby Neptune in the temperate zone of an early-M dwarf

We report on the first star discovered to host a planet detected by radial velocity (RV) observations obtained within the CARMENES survey for exoplanets around M dwarfs. HD 147379 ($V = 8.9$ mag, $M = 0.58 \pm 0.08$ M$_{\odot}$), a bright M0.0V star at a distance of 10.7 pc, is found to undergo periodic RV variations with a semi-amplitude of $K = 5.1\pm0.4$ m s$^{-1}$ and a period of $P = 86.54\pm0.06$ d. The RV signal is found in our CARMENES data, which were taken between 2016 and 2017, and is supported by HIRES/Keck observations that were obtained since 2000. The RV variations are interpreted as resulting from a planet of minimum mass $m_{\rm p}\sin{i} = 25 \pm 2$ M$_{\oplus}$, 1.5 times the mass of Neptune, with an orbital semi-major axis $a = 0.32$ au and low eccentricity ($e < 0.13$). HD 147379b is orbiting inside the temperate zone around the star, where water could exist in liquid form. The RV time-series and various spectroscopic indicators show additional hints of variations at an approximate period of 21.1d (and its first harmonic), which we attribute to the rotation period of the star.

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arXiv2017

K2-139 b: a low-mass warm Jupiter on a 29-day orbit transiting an active K0 V star

We announce the discovery of K2-139 b (EPIC 218916923 b), a transiting warm-Jupiter ($T_\mathrm{eq}$=547$\pm$25 K) on a 29-day orbit around an active (log $R^\prime_\mathrm{HK}$ = $-$4.46 $\pm$ 0.06) K0 V star in K2 Campaign 7. We derive the system's parameters by combining the K2 photometry with ground-based follow-up observations. With a mass of~$0.387 _{ - 0.075 } ^ {+ 0.083 } M_{\rm J}$ and radius of $0.808 _{ - 0.033 } ^ {+ 0.034 } R_{\rm J}$, K2-139 b is one of the transiting warm Jupiters with the lowest mass known to date. The planetary mean density of $0.91 _{ - 0.20} ^ { + 0.24 }$ $\mathrm{g cm^{-3}}$ can be explained with a core of $\sim$50 $M_\oplus$. Given the brightness of the host star ($V$ = 11.653 mag), the relatively short transit duration ($\sim$5 hours), and the expected amplitude of the Rossiter-McLaughlin effect ($\sim25 {\rm m s^{-1}}$ ), K2-139 is an ideal target to measure the spin-orbit angle of a planetary system hosting a warm Jupiter.

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arXiv2017

K2-137 b: an Earth-sized planet in a 4.3-hour orbit around an M-dwarf

We report the discovery from K2 of a transiting terrestrial planet in an ultra-short-period orbit around an M3-dwarf. K2-137 b completes an orbit in only 4.3 hours, the second-shortest orbital period of any known planet, just 4 minutes longer than that of KOI 1843.03, which also orbits an M-dwarf. Using a combination of archival images, AO imaging, RV measurements, and light curve modelling, we show that no plausible eclipsing binary scenario can explain the K2 light curve, and thus confirm the planetary nature of the system. The planet, whose radius we determine to be 0.89 +/- 0.09 Earth radii, and which must have a iron mass fraction greater than 0.45, orbits a star of mass 0.463 +/- 0.052 Msol and radius 0.442 +/- 0.044 Rsol.

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arXiv2017

K2-106, a system containing a metal-rich planet and a planet of lower density

Planets in the mass range from 2 to 15 MEarth are very diverse. Some of them have low densities, while others are very dense. By measuring the masses and radii, the mean densities, structure, and composition of the planets are constrained. These parameters also give us important information about their formation and evolution, and about possible processes for atmospheric loss.We determined the masses, radii, and mean densities for the two transiting planets orbiting K2-106. The inner planet has an ultra-short period of 0.57 days. The period of the outer planet is 13.3 days.Although the two planets have similar masses, their densities are very different. For K2-106b we derive Mb=8.36-0.94+0.96 MEarh, Rb=1.52+/-0.16 REarth, and a high density of 13.1-3.6+5.4 gcm-3. For K2-106c, we find Mc=5.8-3.0+3.3 MEarth, Rc=2.50-0.26+0.27 REarth and a relatively low density of 2.0-1.1+1.6 gcm-3.Since the system contains two planets of almost the same mass, but different distances from the host star, it is an excellent laboratory to study atmospheric escape. In agreement with the theory of atmospheric-loss processes, it is likely that the outer planet has a hydrogen-dominated atmosphere. The mass and radius of the inner planet is in agreement with theoretical models predicting an iron core containing 80+20-30% of its mass. Such a high metal content is surprising, particularly given that the star has an ordinary (solar) metal abundance. We discuss various possible formation scenarios for this unusual planet.

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arXiv2017

Mass determination of K2-19b and K2-19c from radial velocities and transit timing variations

We present FIES@NOT, HARPS-N@TNG, and HARPS@ESO-3.6m radial velocity follow-up observations of K2-19, a compact planetary system hosting three planets, of which the two larger ones, namely K2-19b and K2-19c, are close to the 3:2 mean motion resonance. An analysis considering only the radial velocity measurements detects K2-19b, the largest and most massive planet in the system, with a mass of $54.8\pm7.5$~M${_\oplus}$ and provides a marginal detection of K2-19c, with a mass of M$_\mathrm{c}$=$5.9^{+7.6}_{-4.3}$ M$_\oplus$. We also used the TRADES code to simultaneously model both our RV measurements and the existing transit-timing measurements. We derived a mass of $54.4\pm8.9$~M${_\oplus}$ for K2-19b and of $7.5^{+3.0}_{-1.4}$~M${_\oplus}$ for K2-19c. A prior K2-19b mass estimated by Barros et al. 2015, based principally on a photodynamical analysis of K2-19's light-curve, is consistent with both analysis, our combined TTV and RV analysis, and with our analysis based purely on RV measurements. Differences remain mainly in the errors of the more lightweight planet, driven likely by the limited precision of the RV measurements and possibly some yet unrecognized systematics.

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arXiv2016

K2-99: a subgiant hosting a transiting warm Jupiter in an eccentric orbit and a long-period companion

We report the discovery from K2 of a transiting planet in an 18.25-d, eccentric (0.19$\pm$ 0.04) orbit around K2-99, an 11th magnitude subgiant in Virgo. We confirm the planetary nature of the companion with radial velocities, and determine that the star is a metal-rich ([Fe/H] = 0.20$\pm$0.05) subgiant, with mass $1.60^{+0.14}_{-0.10}~M_\odot$ and radius $3.1\pm 0.1~R_\odot$. The planet has a mass of $0.97\pm0.09~M_{\rm Jup}$ and a radius $1.29\pm0.05~R_{\rm Jup}$. A measured systemic radial acceleration of $-2.12\pm0.04~{\rm m s^{-1} d^{-1}}$ offers compelling evidence for the existence of a third body in the system, perhaps a brown dwarf orbiting with a period of several hundred days.

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arXiv2016

K2-31b, a grazing transiting hot Jupiter on an 1.26-day orbit around a bright G7V star

We report the discovery of K2-31b, the first confirmed transiting hot Jupiter detected by the K2 space mission. We combined K2 photometry with FastCam lucky imaging and FIES and HARPS high-resolution spectroscopy to confirm the planetary nature of the transiting object and derived the system parameters. K2-31b is a 1.8-Jupiter-mass planet on an 1.26-day-orbit around a G7\,V star ($M_\star=0.91$~\Msun, $R_\star=0.78$~\Rsun). The planetary radius is poorly constrained (0.7$<$$R_\mathrm{p}$$<$1.4~\Rjup), owing to the grazing transit and the low sampling rate of the K2 photometry.

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arXiv2015

Long-lived, long-period radial velocity variations in Aldebaran: A planetary companion and stellar activity

We investigate the nature of the long-period radial velocity variations in Alpha Tau first reported over 20 years ago. We analyzed precise stellar radial velocity measurements for Alpha Tau spanning over 30 years. An examination of the Halpha and Ca II 8662 spectral lines, and Hipparcos photometry was also done to help discern the nature of the long-period radial velocity variations. Our radial velocity data show that the long-period, low amplitude radial velocity variations are long-lived and coherent. Furthermore, Halpha equivalent width measurements and Hipparcos photometry show no significant variations with this period. Another investigation of this star established that there was no variability in the spectral line shapes with the radial velocity period. An orbital solution results in a period of P = 628.96 +/- 0.90 d, eccentricity, e = 0.10 +/- 0.05, and a radial velocity amplitude, K = 142.1 +/- 7.2 m/s. Evolutionary tracks yield a stellar mass of 1.13 +/- 0.11 M_sun, which corresponds to a minimum companion mass of 6.47 +/- 0.53 M_Jup with an orbital semi-major axis of a = 1.46 +/- 0.27 AU. After removing the orbital motion of the companion, an additional period of ~ 520 d is found in the radial velocity data, but only in some time spans. A similar period is found in the variations in the equivalent width of Halpha and Ca II. Variations at one-third of this period are also found in the spectral line bisector measurements. The 520 d period is interpreted as the rotation modulation by stellar surface structure. Its presence, however, may not be long-lived, and it only appears in epochs of the radial velocity data separated by $\sim$ 10 years. This might be due to an activity cycle. The data presented here provide further evidence of a planetary companion to Alpha Tau, as well as activity-related radial velocity variations.

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arXiv2015

Kepler423b: a half-Jupiter mass planet transiting a very old solar-like star

We report the spectroscopic confirmation of the Kepler object of interest KOI-183.01 (Kepler-423b), a half-Jupiter mass planet transiting an old solar-like star every 2.7 days. Our analysis is the first to combine the full Kepler photometry (quarters 1-17) with high-precision radial velocity measurements taken with the FIES spectrograph at the Nordic Optical Telescope. We simultaneously modelled the photometric and spectroscopic data-sets using Bayesian approach coupled with Markov chain Monte Carlo sampling. We found that the Kepler pre-search data conditioned (PDC) light curve of KOI-183 exhibits quarter-to-quarter systematic variations of the transit depth, with a peak-to-peak amplitude of about 4.3 % and seasonal trends reoccurring every four quarters. We attributed these systematics to an incorrect assessment of the quarterly variation of the crowding metric. The host star KOI-183 is a G4 dwarf with $M_\star=0.85\pm0.04$ M$_\rm{Sun}$, $R_\star=0.95\pm0.04$ R$_\rm{Sun}$, $T_\mathrm{eff}=5560\pm80$ K, $[M/H]=-0.10\pm0.05$ dex, and with an age of $11\pm2$ Gyr. The planet KOI-183b has a mass of $M_\mathrm{p}=0.595\pm0.081$ M$_\mathrm{Jup}$ and a radius of $R_\mathrm{p}=1.192\pm0.052$ R$_\mathrm{Jup}$, yielding a planetary bulk density of $ρ_\mathrm{p}=0.459\pm0.083$ g/cm$^{3}$. The radius of KOI-183b is consistent with both theoretical models for irradiated coreless giant planets and expectations based on empirical laws. The inclination of the stellar spin axis suggests that the system is aligned along the line of sight. We detected a tentative secondary eclipse of the planet at a 2-$σ$ confidence level ($ΔF_{\mathrm{ec}}=14.2\pm6.6$ ppm) and found that the orbit might have a small non-zero eccentricity of $e=0.019^{+0.028}_{-0.014}$. With a Bond albedo of $A_\mathrm{B}=0.037\pm0.019$, KOI-183b is one of the gas-giant planets with the lowest albedo known so far.

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arXiv2014

Low-amplitude and long-period radial velocity variations in giants HD 3574, 63 Cygni, and HD 216946 (Research Note)

Aims. We study the low-amplitude and long-period variations in evolved stars using precise radial velocity measurements. Methods. The high-resolution, fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) was used from September 2004 to May 2014 as part of the exoplanet search program at the Bohyunsan Optical Astronomy Observatory (BOAO). Results. We report the detection of low-amplitude and long-period orbital radial velocity variations in three evolved stars, HD 3574, 63 Cyg, and HD 216946. They have periods of 1061, 982, and 1382 days and semi-amplitudes of 376, 742, and 699 m/s, respectively.

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arXiv2014

Planetary companions in K giants beta Cancri, mu Leonis, and beta Ursae Minoris

Auns. The aim of our paper is to investigate the low-amplitude and long-period variations in evolved stars with a precise radial velocity (RV) survey. Methods. The high-resolution, the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) was used from 2003 to 2013 for a radial velocity survey of giant stars as part of the exoplanet search program at Bohyunsan Optical Astronomy Observatory (BOAO). Results. We report the detection of three new planetary companions orbiting the K giants beta Cnc, mu Leo, and beta UMi. The planetary nature of the radial velocity variations is supported by analyzes of ancillary data. The HIPPARCOS photometry shows no variations with periods close to those in RV variations and there is no strong correlation between the bisector velocity span (BVS) and the radial velocities for each star. Furthermore, the stars show weak or no core reversal in Ca II H lines indicating that they are inactive stars. The companion to beta Cnc has a minimum mass of 7.8 M_Jup in a 605-day orbit with an eccentricity of 0.08. The giant mu Leo is orbited by a companion of minimum mass of 2.4 M_Jup having a period of 357 days and an eccentricity of 0.09. The giant beta UMi is a known barium star and is suspected of harboring a white dwarf or substellar mass companion. Its companion has a minimum mass of 6.1 M_Jup, a period of 522 days, and an eccentricity e = 0.19.

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arXiv2014

The PLATO 2.0 Mission

PLATO 2.0 has recently been selected for ESA's M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets like ours, including potentially habitable planets? The PLATO 2.0 instrument consists of 34 small aperture telescopes (32 with 25 sec readout cadence and 2 with 2.5 sec candence) providing a wide field-of-view (2232 deg2) and a large photometric magnitude range (4-16 mag). It focusses on bright (4-11 mag) stars in wide fields to detect and characterize planets down to Earth-size by photometric transits, whose masses can then be determined by ground-based radial-velocity follow-up measurements. Asteroseismology will be performed for these bright stars to obtain highly accurate stellar parameters, including masses and ages. The combination of bright targets and asteroseismology results in high accuracy for the bulk planet parameters: 2%, 4-10% and 10% for planet radii, masses and ages, respectively. The planned baseline observing strategy includes two long pointings (2-3 years) to detect and bulk characterize planets reaching into the habitable zone (HZ) of solar-like stars and an additional step-and-stare phase to cover in total about 50% of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect and characterize hundreds of small planets, and thousands of planets in the Neptune to gas giant regime out to the HZ. It will therefore provide the first large-scale catalogue of bulk characterized planets with accurate radii, masses, mean densities and ages. This catalogue will include terrestrial planets at intermediate orbital distances, where surface temperatures are moderate. Coverage of this parameter range with statistical numbers of bulk characterized planets is unique to PLATO 2.0.

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arXiv2013

Kepler-77b: a very low albedo, Saturn-mass transiting planet around a metal-rich solar-like star

We report the discovery of Kepler-77b (alias KOI-127.01), a Saturn-mass transiting planet in a 3.6-day orbit around a metal-rich solar-like star. We combined the publicly available Kepler photometry (quarters 1-13) with high-resolution spectroscopy from the Sandiford@McDonald and FIES@NOT spectrographs. We derived the system parameters via a simultaneous joint fit to the photometric and radial velocity measurements. Our analysis is based on the Bayesian approach and is carried out by sampling the parameter posterior distributions using a Markov chain Monte Carlo simulation. Kepler-77b is a moderately inflated planet with a mass of Mp=0.430+/-0.032 Mjup, a radius of Rp=0.960+/-0.016 Rjup, and a bulk density of 0.603+/-0.055 g/cm^3. It orbits a slowly rotating (P=36+/-6 days) G5V star with M*=0.95+/-0.04 Msun, R*=0.99+/-0.02 Rsun, Teff=5520+/-60 K, [M/H]=0.20+/-0.05, that has an age of 7.5+/-2.0 Gyr. The lack of detectable planetary occultation with a depth higher than about 10 ppm implies a planet geometric and Bond albedo of Ag<0.087+/-0.008 and Ab<0.058+/-0.006, respectively, placing Kepler-77b among the gas-giant planets with the lowest albedo known so far. We found neither additional planetary transit signals nor transit-timing variations at a level of about 0.5 minutes, in accordance with the trend that close-in gas giant planets seem to belong to single-planet systems. The 106 transits observed in short-cadence mode by Kepler for nearly 1.2 years show no detectable signatures of the planet's passage in front of starspots. We explored the implications of the absence of detectable spot-crossing events for the inclination of the stellar spin-axis, the sky-projected spin-orbit obliquity, and the latitude of magnetically active regions.

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arXiv2012

The planet search programme at the ESO CES and HARPS. IV. The search for Jupiter analogues around solar-like stars

In 1992 we began a precision radial velocity (RV) survey for planets around solar-like stars with the Coude Echelle Spectrograph and the Long Camera (CES LC) at the 1.4 m telescope in La Silla (Chile). We have continued the survey with the upgraded CES Very Long Camera (VLC) and HARPS, both at the 3.6 m telescope, until 2007. The observations for 31 stars cover a time span of up to 15 years and the RV precision permit a search for Jupiter analogues. We perform a joint analysis for variability, trends, periodicities, and Keplerian orbits and compute detection limits. Moreover, the HARPS RVs are analysed for correlations with activity indicators (CaII H&K and CCF shape). We achieve a long-term RV precision of 15 m/s (CES+LC, 1992-1998), 9 m/s (CES+VLC, 1999-2006), and 2.8 m/s (HARPS, 2003-2009, including archive data), resp. This enables us to confirm the known planets around Iota Hor, HR 506, and HR 3259. A steady RV trend for Eps Ind A can be explained by a planetary companion. On the other hand, we find previously reported trends to be smaller for Beta Hyi and not present for Alp Men. The candidate planet Eps Eri b was not detected despite our better precision. Also the planet announced for HR 4523 cannot be confirmed. Long-term trends in several of our stars are compatible with known stellar companions. We provide a spectroscopic orbital solution for the binary HR 2400 and refined solutions for the planets around HR 506 and Iota Hor. For some other stars the variations could be attributed to stellar activity. The occurrence of two Jupiter-mass planets in our sample is in line with the estimate of 10% for the frequency of giant planets with periods smaller than 10 yr around solar-like stars. We have not detected a Jupiter analogue, while the detections limits for circular orbits indicate at 5 AU a sensitivity for minimum mass of at least 1 M_Jup (2 M_Jup) for 13% (61%) of the stars.

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