E-viri
Recenzirano
Odprti dostop
-
Van Eylen, V; Astudillo-Defru, N; Bonfils, X; Livingston, J; Hirano, T; Luque, R; Lam, K W F; Justesen, A B; Winn, J N; Gandolfi, D; Nowak, G; Palle, E; Albrecht, S; Dai, F; Campos Estrada, B; Owen, J E; Foreman-Mackey, D; Fridlund, M; Korth, J; Mathur, S; Forveille, T; Mikal-Evans, T; Osborne, H L M; Ho, C S K; Almenara, J M; Artigau, E; Barragán, O; Barros, S C C; Bouchy, F; Cabrera, J; Caldwell, D A; Charbonneau, D; Chaturvedi, P; Cochran, W D; Csizmadia, S; Damasso, M; Delfosse, X; De Medeiros, J R; Díaz, R F; Doyon, R; Esposito, M; Fűrész, G; Figueira, P; Georgieva, I; Goffo, E; Grziwa, S; Guenther, E; Hatzes, A P; Jenkins, J M; Kabath, P; Knudstrup, E; Latham, D W; Lavie, B; Lovis, C; Mennickent, R E; Mullally, S E; Murgas, F; Narita, N; Pepe, F A; Persson, C M; Redfield, S; Ricker, G R; Santos, N C; Seager, S; Serrano, L M; Smith, A M S; Mascareño, A Suárez; Subjak, J; Twicken, J D; Udry, S; Vanderspek, R; Zapatero Osorio, M R
Monthly notices of the Royal Astronomical Society, 10/2021, Letnik: 507, Številka: 2Journal Article
ABSTRACT We report on precise Doppler measurements of L231-32 (TOI-270), a nearby M dwarf (d = 22 pc, M⋆ = 0.39 M⊙, R⋆ = 0.38 R⊙), which hosts three transiting planets that were recently discovered using data from the Transiting Exoplanet Survey Satellite (TESS). The three planets are 1.2, 2.4, and 2.1 times the size of Earth and have orbital periods of 3.4, 5.7, and 11.4 d. We obtained 29 high-resolution optical spectra with the newly commissioned Echelle Spectrograph for Rocky Exoplanet and Stable Spectroscopic Observations (ESPRESSO) and 58 spectra using the High Accuracy Radial velocity Planet Searcher (HARPS). From these observations, we find the masses of the planets to be 1.58 ± 0.26, 6.15 ± 0.37, and 4.78 ± 0.43 M⊕, respectively. The combination of radius and mass measurements suggests that the innermost planet has a rocky composition similar to that of Earth, while the outer two planets have lower densities. Thus, the inner planet and the outer planets are on opposite sides of the ‘radius valley’ – a region in the radius-period diagram with relatively few members – which has been interpreted as a consequence of atmospheric photoevaporation. We place these findings into the context of other small close-in planets orbiting M dwarf stars, and use support vector machines to determine the location and slope of the M dwarf (Teff < 4000 K) radius valley as a function of orbital period. We compare the location of the M dwarf radius valley to the radius valley observed for FGK stars, and find that its location is a good match to photoevaporation and core-powered mass-loss models. Finally, we show that planets below the M dwarf radius valley have compositions consistent with stripped rocky cores, whereas most planets above have a lower density consistent with the presence of a H-He atmosphere.
Avtor
Vnos na polico
Trajna povezava
- URL:
Faktor vpliva
Dostop do baze podatkov JCR je dovoljen samo uporabnikom iz Slovenije. Vaš trenutni IP-naslov ni na seznamu dovoljenih za dostop, zato je potrebna avtentikacija z ustreznim računom AAI.
Leto | Faktor vpliva | Izdaja | Kategorija | Razvrstitev | ||||
---|---|---|---|---|---|---|---|---|
JCR | SNIP | JCR | SNIP | JCR | SNIP | JCR | SNIP |
Baze podatkov, v katerih je revija indeksirana
Ime baze podatkov | Področje | Leto |
---|
Povezave do osebnih bibliografij avtorjev | Povezave do podatkov o raziskovalcih v sistemu SICRIS |
---|
Vir: Osebne bibliografije
in: SICRIS
To gradivo vam je dostopno v celotnem besedilu. Če kljub temu želite naročiti gradivo, kliknite gumb Nadaljuj.