Speaker
Adam Ritchey
(University of Washington)
Description
We present a detailed analysis of the physical conditions in shocked interstellar clouds along two lines of sight through the Vela supernova remnant using new high-resolution HST/STIS spectra acquired at FUV wavelengths. From the relative populations of collisionally-excited fine-structure levels in C I and O I, we derive unique solutions for the gas density and kinetic temperature in discrete radial velocity bins along each line of sight. Observations of collisionally-excited Si II provide electron densities, which are used, in conjunction with the previously-derived densities and temperatures, to estimate the strength of the local radiation field from a consideration of the ionization balance between neutral and singly-ionized carbon. Finally, variations in nickel depletion levels allow us to estimate the degree to which dust grains have been destroyed in the highly compressed regions. We discuss the implications of these new results for models of cloud compression and dust grain destruction in supernova shocks.
Author
Adam Ritchey
(University of Washington)