Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.705597
Title: The acceleration and transport of electron populations in solar flares
Author: Stackhouse, Duncan James
ISNI:       0000 0004 6060 7779
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 2017
Availability of Full Text:
Access from EThOS:
Access from Institution:
Abstract:
Solar flares are known to accelerate electrons to high energies, resulting in the movement of these particles throughout the Sun's atmosphere. Although this has been known since the middle of the last century, it is still unknown quite how these particles are accelerated, how they are transported and where the energization takes place. This thesis is concerned with these key questions of solar physics, using a mixture of analytical and numerical modelling in conjunction with the valuable diagnostic tool of the X-rays observed by the Reuven-Ramaty High Energy Solar Spectroscopic Imager (RHESSI). First, imaging spectroscopy with RHESSI is shown, focussing on how to infer to the underlying electron distribution producing the X-ray photons and how this can be used to produce more realistic models. Secondly, a model where the region in which the electrons are accelerated, stopped and emit X-rays is the same is presented, driven specifically by observations of such sources by RHESSI. This admits a steady-state kappa distribution solution and it is shown that the relaxation of an originally thermal Maxwellian population of electrons to this final state proceeds as a wavefront in velocity space. Finally, a model which takes account of recent studies showing the extended nature of the acceleration region within the loops of solar flares is considered. For the first time the intrinsic spatial dependencies of acceleration and transport are explicitly studied, showing the importance of accounting for this in future modelling of solar flares.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.705597  DOI: Not available
Keywords: QB Astronomy ; QC Physics
Share: