Evaporation of Jupiter-like planets orbiting extreme horizontal branch stars

Abstract

We study the evaporation of planets orbiting close to hot (extreme) horizontal branch (EHB) stars. These planets survived the common envelope phase inside the envelope of the red giant star progenitor. We find that Jupiter-like planets orbiting within ∼10R⊙ from an EHB star suffer a non-negligible mass-loss during their ∼108-yr evolution on the horizontal branch. The evaporated gas is ionized and becomes a source of Balmer lines. Such planets might be detected by the periodic variation of the Doppler shift of the Balmer lines. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.