K2-140b and K2-180b - Characterization of a hot Jupiter and a mini-Neptune from the K2 mission

Korth, J.; Csizmadia, Sz; Gandolfi, D.; Fridlund, M.; Pätzold, M.; Hirano, T.; Livingston, J.; Persson, C. M.; Deeg, H. J.; Justesen, A. B.; Barragán, O.; Grziwa, S.; Endl, M.; Tronsgaard, R.; Dai, F.; Cochran, W. D.; Albrecht, S.; Alonso, R.; Cabrera, J.; Cauley, P. W.; Cusano, F.; Eigmüller, Ph; Erikson, A.; Esposito, M.; Guenther, E. W.; Hatzes, A. P.; Hidalgo, D.; Kuzuhara, M.; Montañes, P.; Napolitano, N. R.; Narita, N.; Niraula, P.; Nespral, D.; Nowak, G.; Palle, E.; Petrillo, C. E.; Redfield, S.; Prieto-Arranz, J.; Rauer, H.; Smith, A. M. S.; Tortora, C.; Van Eylen, V.; Winn, J. N.
Referencia bibliográfica

Monthly Notices of the Royal Astronomical Society, Volume 482, Issue 2, p.1807-1823

Fecha de publicación:
1
2019
Número de autores
43
Número de autores del IAC
9
Número de citas
19
Número de citas referidas
18
Descripción
We report the independent discovery and characterization of two K2 planets: K2-180b, a mini-Neptune-sized planet in an 8.9-d orbit transiting a V = 12.6 mag, metal-poor ([Fe/H] = -0.65 ± 0.10) K2V star in K2 campaign 5; K2-140b, a transiting hot Jupiter in a 6.6-d orbit around a V = 12.6 mag G6V ([Fe/H] = + 0.10 ± 0.10) star in K2 campaign 10. Our results are based on K2 time-series photometry combined with high-spatial resolution imaging and high-precision radial velocity measurements. We present the first mass measurement of K2-180b. K2-180b has a mass of Mp = 11.3 ± 1.9 M_{\oplus} and a radius of Rp = 2.2 ± 0.1 R_{\oplus}, yielding a mean density of ρp = 5.6 ± 1.9 g cm-3, suggesting a rocky composition. Given its radius, K2-180b is above the region of the so-called `planetary radius gap'. K2-180b is in addition not only one of the densest mini-Neptune-sized planets, but also one of the few mini-Neptune-sized planets known to transit a metal-poor star. We also constrain the planetary and orbital parameters of K2-140b and show that, given the currently available Doppler measurements, the eccentricity is consistent with zero, contrary to the results of a previous study.
Proyectos relacionados
Image withthe projects' name
Exoplanetas y Astrobiología
La búsqueda de vida en el Universo se ha visto impulsada por los recientes descubrimientos de planetas alrededor de otras estrellas (los llamados exoplanetas), convirtiéndose en uno de los campos más activos dentro de la Astrofísica moderna. En los últimos años los descubrimientos cada vez más numerosos de nuevos exoplanetas y los últimos avances
Enric
Pallé Bago