An approximate recipe of chromospheric radiative losses for solar flares

TL;DR

This paper develops a new, more accurate lookup table for estimating chromospheric radiative losses during solar flares, improving upon previous semi-empirical recipes by using detailed radiative hydrodynamic simulations.

Contribution

The authors create a new approximate recipe for flare chromospheric radiative losses based on radiative hydrodynamic models, enhancing accuracy over existing semi-empirical methods.

Findings

New lookup tables better match detailed radiative loss calculations.

Improved approximation for flare conditions over previous recipes.

Method validated against a grid of radiative hydrodynamic simulations.

Abstract

Radiative losses in the chromosphere are very important in the energy balance. There have been efforts to make simple lookup tables for chromospheric radiative losses in the quiet Sun. During solar flares, the atmospheric conditions are quite different, and the currently available recipe of Gan & Fang (1990) is constructed from semi-empirical models. It remains to be evaluated how these recipes work in flare conditions. We aim to construct an approximate recipe of chromospheric radiative losses for solar flares. We follow the method of Carlsson & Leenaarts (2012) to tabulate the optically thin radiative loss, escape probability, and ionization fraction, while using a grid of flare models from radiative hydrodynamic simulations as our dataset. We provide new lookup tables to calculate chromospheric radiative losses for flares. Compared with previous recipes, our recipe provides a better approximation to the detailed radiative losses for flares.