Open AccessEfficient metal emissions in the upper atmospheres of close‐in exoplanets
Author(s) -
Liu Lei,
Tian Feng
Publication year - 2018
Publication title -
earth and planetary physics
Language(s) - English
Resource type - Journals
ISSN - 2096-3955
DOI - 10.26464/epp2018003
Subject(s) - exoplanet , planet , astrobiology , radiative transfer , hot jupiter , physics , environmental science , population , radiative cooling , atmosphere (unit) , atmospheric sciences , gas giant , astrophysics , meteorology , demography , quantum mechanics , sociology
Atmospheric escape is a key process controlling the long term evolution of planets. Radiative cooling competes for energy against atmospheric escape in planetary upper atmospheres. In this work, we use a population balance method and a Monte Carlo model to calculate the previously ignored emissions of metals (C, N, O and their ions) and compare them with radiative recombination of H II and Ly‐α emission of H I, which are the most efficient cooling mechanisms currently recognized in the upper atmospheres of hot Jupiters. The results show that the emissions of C, N, O and their ions are strong non‐linear functions of environmental parameters (temperature, density, etc.) and are likely to be efficient cooling mechanisms in the upper atmospheres of close‐in exoplanets.