Studying Particle Acceleration in Solar Flares via Subsecond X-ray Spikes: Analysis and Instrumentation

Abstract

Solar flares are explosive releases of magnetic energy in the solar atmosphere. Driven by a process known as magnetic reconnection, these events are associated with a wide array of interesting and dynamic phenomena. One such phenomenon is the acceleration of electrons to extremely high, nonthermal energies (10s-100s of keV). How these particles are accelerated is an outstanding question. Studying the X-ray radiation produced by these electrons is a direct means of studying the particles themselves. A potentially useful, yet rarely explored, feature in the solar flare X-ray flux is the existence of subsecond spikes of emission. In this dissertation I first provide a broad overview of the solar physics relevant to the study of particle acceleration and highlight the major past studies which focused on subsecond X-ray spikes. I then present the case study I performed in analyzing subsecond X-ray spikes in Fermi Gamma-ray Burst Monitor data. This study presents a comprehensive method of identifying, measuring, and analyzing these spikes. The results of this work help constrain the temporal characteristics of acceleration models as well as paving the way for future fast time domain analysis of solar flares using Fermi GBM data. I also discuss the work I have completed for the University of Minnesota Small Satellite Research Laboratory (UMNSSRL) developing fast time precision solar X-ray instruments. This included the founding of the UMN-SSRL itself, the creation of an analytical detector model for inorganic scintillators, and the development of the scientific requirements for multiple CubeSats. This work aims to progress the development of solar X-ray instrumentation capable of observing subsecond X-ray spikes.