RHESSI Investigation of X-ray Coronal Sources During Decay Phase of Solar Flares: II. Energy Balance

TL;DR

This study uses RHESSI data to analyze the energy balance in long-duration solar flare decay phases, focusing on the effectiveness of magnetic reconnection and precise energy release calculations.

Contribution

It introduces a method to evaluate the energy release rate and the accuracy of energy term determinations during flare decay using image spectral analysis.

Findings

Magnetic reconnection sustains decay phase X-ray emissions.

Energy release rate can be quantitatively estimated from spectral data.

Terms in the energy equation are determined with known accuracy.

Abstract

As it was shown by many authors, a slow decrease in X-rays observed during the decay phase of long duration flares (LDE) can be explained only by a magnetic reconnection and energy release ceaselessly ongoing in the coronal part of a flare. Using RHESSI data we try to answer two following questions. How effective are these processes at the LDEs decay phase and how can precisely the energy release rate be calculated based on these data? To answer the questions images of the selected LDEs during their decay phase were reconstructed. Physical parameters of flare coronal sources obtained from image spectral analysis allowed us to study the efficiency of the energy release process. We also examined terms included in the energy equation to find out what is the accuracy of determination of each term.