The Evolutionary Track of H/He Envelopes of the Observed Population of Sub-Neptunes and Super-Earths

Autor(es)

Estrela, Raissa ^{[1, 2]} ; Swain, Mark R. ^[1] ; Gupta, Akash ^[3] ; Sotin, Christophe ^[1] ; Valio, Adriana ^[2]

Afiliação do(s) autor(es)

^[1] CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 - USA

^[2] Univ Prebiteriana Mackenzie, Ctr Radioastron & Astrophys Mackenzie, R Consolacao 896, BR-01301000 Sao Paulo, SP - Brazil

^[3] Univ Calif Los Angeles, Dept Earth Planetary & Space Sci, Los Angeles, CA 90095 - USA

• Tipo de documento: Artigo Científico
• Fonte: ASTROPHYSICAL JOURNAL; v. 898, n. 2 AUG 2020.
• Citações Web of Science: 0

Resumo

The observational detection of a localized reduction in the small planet occurrence rate, sometimes termed a ``gap,{''} is an exciting discovery because of the implications for planet evolutionary history. This gap appears to define a transition region in which sub-Neptune planets are believed to have lost their H/He envelopes, potentially by photoevaporation or core powered mass loss, and have thus been transformed into bare core terrestrial planets. Here we investigate the transition between sub-Neptunes and super-Earths using a real sample of observed small close-in planets and applying envelope evolution models of the H/He envelope together with the mass-radius diagram and a photoevaporation model. We find that photoevaporation can explain the H/He envelope loss of most super-Earths in 100 Myr, although an additional loss mechanism appears necessary in some planets. We explore the possibility that these planets' families have different core masses and find a continuum in the primordial population of the strongly irradiated super-Earths and the sub-Neptunes. Our analysis also shows that close-orbiting sub-Neptunes withR R(circle plus)typically lose similar to 30% of their primordial envelope. (AU)

• Processo FAPESP: 16/25901-9 - Interações magnéticas no sistema estrela-planeta e suas consequências na habitabilidade planetária
• Beneficiário: Raissa de Lourdes Freitas Estrela
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 18/09984-7 - Investigando a formação de hazes e o balanço energético nas atmosferas de exoplanetas com o Telescópio Espacial hubble
• Beneficiário: Raissa de Lourdes Freitas Estrela
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado