Extreme Ultra-Violet Spectroscopy of the Lower Solar Atmosphere During Solar Flares

TL;DR

This paper reviews recent advances in extreme ultraviolet spectroscopy of the lower solar atmosphere during solar flares, highlighting diagnostic tools and data from Hinode/EIS and SDO/EVE.

Contribution

It provides a comprehensive overview of recent spectroscopic techniques and findings, emphasizing the use of Hinode/EIS and SDO/EVE data in solar flare studies.

Findings

Enhanced understanding of temperature and density diagnostics during flares

Identification of nonthermal broadening and Doppler shifts in EUV lines

Insights into solar atmospheric energetics and composition

Abstract

The extreme ultraviolet portion of the solar spectrum contains a wealth of diagnostic tools for probing the lower solar atmosphere in response to an injection of energy, particularly during the impulsive phase of solar flares. These include temperature and density sensitive line ratios, Doppler shifted emission lines and nonthermal broadening, abundance measurements, differential emission measure profiles, and continuum temperatures and energetics, among others. In this paper I shall review some of the advances made in recent years using these techniques, focusing primarily on studies that have utilized data from Hinode/EIS and SDO/EVE, while also providing some historical background and a summary of future spectroscopic instrumentation.