The Physical Conditions Pertaining to Some Possible Supernova Remnants

Citation

Parker, Robert Allan Ridley (1963) The Physical Conditions Pertaining to Some Possible Supernova Remnants. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/XGR5-7574. https://resolver.caltech.edu/CaltechETD:etd-04292008-090916

Abstract

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. A large number of spectrophotometric observations have been made of 16 individual filaments in five possible supernova remnants, S 22, S 147, IC 443, NGC 6888, and the Cygnus Loop. Using these observations and making certain assumptions regarding abundances (that relative to Hydrogen we will expect abundances to be at least normal), it is shown that temperatures vary greatly within the filaments but are generally of the order of ten to fifteen thousand degrees for the regions from which we receive most of the [OII], [NII], [SII] , and Balmer emission. The densities for these same regions are of the order of a few hundred electrons per cubic centimeter. From these conclusions it is further indicated that: 1) the source of excitation of the Balmer lines is collisional; 2) all of the observed radio radiation from IC 443 and the Cygnus Loop can, by extrapolation from the observed total H[...] flux, be accounted for as thermal radiation; 3) the total mass of the visible filaments of IC 443, NGC 6888 and the Cygnus Loop is of the order of several tens of solar masses; and 4) the apparent filaments are actually only the results of the projection effect for shells.

Thesis Files