# The Detectability of Neon Fluorescence and Measurement of the Solar Photospheric Neon Abundance - Astrophysics

Abstract: Monte Carlo calculations of the Ne K$\alpha$ line fluoresced by coronalx-rays and emitted near the temperature minimum region of the solar atmospherehave been employed to investigate the use of this feature to measure directlythe solar photospheric Ne abundance. Though very weak, comparison with spectralline databases indicates that at plasma temperatures typical of the quiet Sunand cool active regions $\leq 2\times 10^6$ K the line is isolated andunblended. A canonical solar chemical composition yields an equivalent width of$\sim 6$ m\AA 0.3 eV when observed at heliocentric angles $\sim 0$. For a 1arcmin field of view, photon fluxes at Earth are of order 0.2 ph s$^{-1}$ forthe quiet Sun, rendering the Ne K$\alpha$ fluorescent line a quite feasiblemeans for determining the solar photospheric Ne content.

Author: Jeremy J. Drake, Barbara Ercolano

Source: https://arxiv.org/