Evaporation of Jupiter like planets orbiting extreme horizontal branch stars

TL;DR

This study investigates how Jupiter-like planets close to hot horizontal branch stars lose mass through evaporation, potentially detectable via spectral line variations, during their evolution over hundreds of millions of years.

Contribution

It presents the first analysis of planetary evaporation around EHB stars, highlighting the potential for detecting evaporating planets through spectral signatures.

Findings

Jupiter-like planets within 10 solar radii can lose significant mass over 10^8 years.

Evaporated gas from these planets can produce observable Balmer emission lines.

Periodic Doppler shifts in Balmer lines could reveal the presence of evaporating planets.

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 reg giant star progenitor. We find that Jupiter-like planets orbiting within 10Ro from an EHB star suffers a non-negligible mass-loss during their 10^8 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.