A binary merger origin for inflated hot Jupiter planets

作者：Martin E L^*; Spruit H C; Tata R

来源：Astronomy & Astrophysics, 2011, 535: A50.

DOI：10.1051/0004-6361/201116907

• planets and satellites: formation
• binaries: eclipsing
• planets and satellites: dynamical evolution and stability
• blue stragglers
• methods: statistical

We hypothesize that hot Jupiters with inflated sizes represent a separate planet formation channel, the merging of two low-mass stars. We show that the abundance and properties of W UMa stars and low mass detached binaries are consistent with their being possible progenitors. The degree of inflation of the transiting hot Jupiters correlates with their expected spiral-in life time by tidal dissipation, and this could indicate youth if the stellar dissipation parameter Q(*)' is sufficiently low. Several Jupiter-mass planets can form in the massive compact disk formed in a merger event. Gravitational scattering between them can explain the high incidence of excentric, inclined, and retrograde orbits. If the population of inflated planets is indeed formed by a merger process, their frequency should be much higher around blue stragglers than around T Tauri stars.

• 出版日期2011-11