3 research outputs found
TOI-733 b -- a planet in the small-planet radius valley orbiting a Sun-like star
We report the discovery of a hot ( 1055 K) planet in
the small planet radius valley transiting the Sun-like star TOI-733, as part of
the KESPRINT follow-up program of TESS planets carried out with the HARPS
spectrograph. TESS photometry from sectors 9 and 36 yields an orbital period of
= days and a radius of
= .
Multi-dimensional Gaussian process modelling of the radial velocity
measurements from HARPS and activity indicators, gives a semi-amplitude of
= m s, translating into a planet mass of
= . These
parameters imply that the planet is of moderate density ( =
g cm) and place it in the transition
region between rocky and volatile-rich planets with H/He-dominated envelopes on
the mass-radius diagram. Combining these with stellar parameters and
abundances, we calculate planet interior and atmosphere models, which in turn
suggest that TOI-733 b has a volatile-enriched, most likely secondary outer
envelope, and may represent a highly irradiated ocean world - one of only a few
such planets around G-type stars that are well-characterised.Comment: Accepted for publication in A&
HD 20329b: An ultra-short-period planet around a solar-type star found by TESS
We used TESS light curves and HARPS-N spectrograph radial velocity
measurements to establish the physical properties of the transiting exoplanet
candidate found around the star HD 20329 (TOI-4524). We performed a joint fit
of the light curves and radial velocity time series to measure the mass,
radius, and orbital parameters of the candidate. We confirm and characterize HD
20329b, an ultra-short-period (USP) planet transiting a solar-type star. The
host star (HD 20329, mag, mag) is characterized by its G5
spectral type with M,
R, and K; it is located at a distance pc. By jointly
fitting the available TESS transit light curves and follow-up radial velocity
measurements, we find an orbital period of
days, a planetary radius of , and a mass of
, implying a mean density of
g cm. HD 20329b joins the 30
currently known USP planets with radius and Doppler mass measurements.Comment: Accepted for publication in A&A, 26 page
HD 20329b: An ultra-short-period planet around a solar-type star found by TESS
We used TESS light curves and HARPS-N spectrograph radial velocity measurements to establish the physical properties of the transiting exoplanet candidate found around the star HD 20329 (TOI-4524). We performed a joint fit of the light curves and radial velocity time series to measure the mass, radius, and orbital parameters of the candidate. We confirm and characterize HD 20329b, an ultra-short-period (USP) planet transiting a solar-type star. The host star (HD 20329, V = 8.74 mag, J = 7.5 mag) is characterized by its G5 spectral type with M_star= 0.90 ± 0.05 M_sun, R_star = 1.13 ± 0.02 R_sun, and T_eff = 5596 ± 50 K; it is located at a distance d= 63.68 ± 0.29 pc. By jointly fitting the available TESS transit light curves and follow-up radial velocity measurements, we find an orbital period of 0.9261 ± (0.5× 10^-4) days, a planetary radius of 1.72 ± 0.07 R_earth, and a mass of 7.42 ± 1.09 M_earth, implying a mean density of rho_planet = 8.06 ± 1.53 g cm^-3. HD 20329b joins the ~30 currently known USP planets with radius and Doppler mass measurements