Bibcode
Bonfanti, A.; Gandolfi, D.; Egger, J. A.; Fossati, L.; Cabrera, J.; Krenn, A.; Alibert, Y.; Benz, W.; Billot, N.; Florén, H. -G.; Lendl, M.; Adibekyan, V.; Salmon, S.; Santos, N. C.; Sousa, S. G.; Wilson, T. G.; Barragán, O.; Collier Cameron, A.; Delrez, L.; Esposito, M.; Goffo, E.; Osborne, H.; Osborn, H. P.; Serrano, L. M.; Van Eylen, V.; Alarcon, J.; Alonso, R.; Anglada, G.; Bárczy, T.; Barrado Navascues, D.; Barros, S. C. C.; Baumjohann, W.; Beck, M.; Beck, T.; Bedell, M.; Bonfils, X.; Borsato, L.; Brandeker, A.; Broeg, C.; Charnoz, S.; Corral Van Damme, C.; Csizmadia, Sz.; Cubillos, P. E.; Davies, M. B.; Deleuil, M.; Demangeon, O. D. S.; Demory, B. -O.; Ehrenreich, D.; Erikson, A.; Fortier, A.; Fridlund, M.; Gillon, M.; Güdel, M.; Hoyer, S.; Isaak, K. G.; Kerschbaum, F.; Kiss, L. L.; Laskar, J.; Lecavelier des Etangs, A.; Lorenzo-Oliveira, D.; Lovis, C.; Magrin, D.; Marafatto, L.; Maxted, P. F. L.; Meléndez, J.; Mordasini, C.; Nascimbeni, V.; Olofsson, G.; Ottensamer, R.; Pagano, I.; Pallé, E.; Peter, G.; Piazza, D.; Piotto, G.; Pollacco, D.; Queloz, D.; Ragazzoni, R.; Rando, N.; Rauer, H.; Ribas, I.; Scandariato, G.; Ségransan, D.; Simon, A. E.; Smith, A. M. S.; Steller, M.; Szabó, Gy. M.; Thomas, N.; Udry, S.; Ulmer, B.; Van Grootel, V.; Venturini, J.; Walton, N. A.
Bibliographical reference
Astronomy and Astrophysics
Advertised on:
3
2023
Journal
Citations
0
Refereed citations
0
Description
Context. TOI-1055 is a Sun-like star known to host a transiting Neptune-sized planet on a 17.5-day orbit (TOI-1055 b). Radial velocity (RV) analyses carried out by two independent groups using nearly the same set of HARPS spectra have provided measurements of planetary masses that differ by ∼2σ.
Aims: Our aim in this work is to solve the inconsistency in the published planetary masses by significantly extending the set of HARPS RV measurements and employing a new analysis tool that is able to account and correct for stellar activity. Our further aim was to improve the precision on measurements of the planetary radius by observing two transits of the planet with the CHEOPS space telescope.
Methods: We fit a skew normal function to each cross correlation function extracted from the HARPS spectra to obtain RV measurements and hyperparameters to be used for the detrending. We evaluated the correlation changes of the hyperparameters along the RV time series using the breakpoint technique. We performed a joint photometric and RV analysis using a Markov chain Monte Carlo scheme to simultaneously detrend the light curves and the RV time series.
Results: We firmly detected the Keplerian signal of TOI-1055 b, deriving a planetary mass of Mb = 20.4−2.5+2.6 M⊕ (∼12%). This value is in agreement with one of the two estimates in the literature, but it is significantly more precise. Thanks to the TESS transit light curves combined with exquisite CHEOPS photometry, we also derived a planetary radius of Rb = 3.490−0.064+0.070 R⊕ (∼1.9%). Our mass and radius measurements imply a mean density of ρb = 2.65−0.35+0.37 g cm−3 (∼14%). We further inferred the planetary structure and found that TOI-1055 b is very likely to host a substantial gas envelope with a mass of 0.41−0.20+0.34 M⊕ and a thickness of 1.05−0.29+0.30 R⊕.
Conclusions: Our RV extraction combined with the breakpoint technique has played a key role in the optimal removal of stellar activity from the HARPS time series, enabling us to solve the tension in the planetary mass values published so far for TOI-1055 b. Light curves are only available at the CDS via anonymous ftp to cdsarc.cds.unistra.fr (ftp://130.79.128.5) or via https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/671/L8 This article uses data from CHEOPS program CH_PR100024. Based on observations made with ESO-3.6 m telescope at the La Silla Observatory under programme IDs 106.21TJ.001, 188.C-0265, and 0100.D-044.
Aims: Our aim in this work is to solve the inconsistency in the published planetary masses by significantly extending the set of HARPS RV measurements and employing a new analysis tool that is able to account and correct for stellar activity. Our further aim was to improve the precision on measurements of the planetary radius by observing two transits of the planet with the CHEOPS space telescope.
Methods: We fit a skew normal function to each cross correlation function extracted from the HARPS spectra to obtain RV measurements and hyperparameters to be used for the detrending. We evaluated the correlation changes of the hyperparameters along the RV time series using the breakpoint technique. We performed a joint photometric and RV analysis using a Markov chain Monte Carlo scheme to simultaneously detrend the light curves and the RV time series.
Results: We firmly detected the Keplerian signal of TOI-1055 b, deriving a planetary mass of Mb = 20.4−2.5+2.6 M⊕ (∼12%). This value is in agreement with one of the two estimates in the literature, but it is significantly more precise. Thanks to the TESS transit light curves combined with exquisite CHEOPS photometry, we also derived a planetary radius of Rb = 3.490−0.064+0.070 R⊕ (∼1.9%). Our mass and radius measurements imply a mean density of ρb = 2.65−0.35+0.37 g cm−3 (∼14%). We further inferred the planetary structure and found that TOI-1055 b is very likely to host a substantial gas envelope with a mass of 0.41−0.20+0.34 M⊕ and a thickness of 1.05−0.29+0.30 R⊕.
Conclusions: Our RV extraction combined with the breakpoint technique has played a key role in the optimal removal of stellar activity from the HARPS time series, enabling us to solve the tension in the planetary mass values published so far for TOI-1055 b. Light curves are only available at the CDS via anonymous ftp to cdsarc.cds.unistra.fr (ftp://130.79.128.5) or via https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/671/L8 This article uses data from CHEOPS program CH_PR100024. Based on observations made with ESO-3.6 m telescope at the La Silla Observatory under programme IDs 106.21TJ.001, 188.C-0265, and 0100.D-044.
Related projects
Helio and Astero-Seismology and Exoplanets Search
The principal objectives of this project are: 1) to study the structure and dynamics of the solar interior, 2) to extend this study to other stars, 3) to search for extrasolar planets using photometric methods (primarily by transits of their host stars) and their characterization (using radial velocity information) and 4) the study of the planetary
Savita
Mathur
Exoplanets and Astrobiology
The search for life in the universe has been driven by recent discoveries of planets around other stars (known as exoplanets), becoming one of the most active fields in modern astrophysics. The growing number of new exoplanets discovered in recent years and the recent advance on the study of their atmospheres are not only providing new valuable
Enric
Pallé Bago