Thesis Defense: Sarah Trowbridge Heine

Friday May 2, 2014 3:00 pm
Marlar Lounge (37-252)


Sarah Trowbridge Heine

High-Resolution Studies of Charge Exchange in Supernova Remnants with Magellan, XMM-Newton, and Micro-X

Committee: Enectali Figueroa-Feliciano, Claude Canizares, and Allan Adams

Abstract: Charge exchange, the semi-resonant transfer of an electron from a neutral atom to an excited state in an energetic ion, can occur in plasmas where energetic ions are incident on a cold, at least partially neutral gas.  Supernova remnants, especially in the immediate shock region, provide conditions conducive to charge exchange.  The emission from post charge-exchange ions as the captured electron cascades down to the ground state, can shed light on the physical conditions of the shock and the immediate post-shock material, providing an important tool for understanding supernova explosions and their aftermath.

In the first half of this thesis, I study charge exchange in the galactic supernova remnant G296.1-0.5 in the optical band using the IMACS instrument on the Magellan Baade Telescope at Las Campanas Observatory, seeks to identify ‘Balmer-dominated shocks’ in the remnant, which signal the occurrence of charge exchange between hot, post-shock protons and colder neutral hydrogen in the environment.  I also discuss the process of measuring charge exchange in the X-ray band and the need for more sensitive instrumentation in this regime.

The focus of the second half of the thesis is Micro-X: a sounding rocket-borne, X-ray telescope, utilizing an array of microcalorimeters to achieve high energy resolution for even extended sources.  I describe the design and commissioning of the payload and the steps toward launch, which is anticipated in the spring of 2015.