Date of Award
Thesis open access
The Crab Nebula contains a number of regions of anomalous elemental abundances, including a large band of nearly pure helium and several pockets that display unusually strong nickel lines. Previous attempts at their explanation have proven unsatisfactory, so we turn our focus to the pulsar which powers the nebula. Following the suggestion that positive ions could be removed from the surface of the central neutron star (rich in iron-peak nuclei), we have examined this possibility within the framework of the Ruderman & Sutherland polar gap magnetospheric model. We identify two processes, surface irradiation by electrons and subsurface electron flows, that, owing to the Crab Pulsar’s youth, appear to raise the surface temperature of the magnetic polar cap region to levels at which significant thermionic emission of iron-peak nuclei occurs.
Vanderveer, Steven J., "On the Removal of Iron-Peak Nuclei from the Surface of the Crab Pulsar" (2007). Physics & Astronomy Honors Theses. 3.