Grain destruction in a supernova remnant shock wave

Abstract

Dust grains are sputtered away in the hot gas behind shock fronts in supernova remnants (SNRs), gradually enriching the gas phase with refractory elements. We have measured emission in C IV λ1550 from C atoms sputtered from dust in the gas behind a non-radiative shock wave in the northern Cygnus Loop. Overall, the intensity observed behind the shock agrees approximately with predictions from model calculations that match the Spitzer 24 μm and the X-ray intensity profiles. Thus, these observations confirm the overall picture of dust destruction in SNR shocks and the sputtering rates used in models. However, there is a discrepancy in that the C IV intensity 10″ behind the shock is too high compared with the intensities at the shock and 25″ behind it. Variations in the density, hydrogen neutral fraction, and the dust properties over parsec scales in the pre-shock medium limit our ability to test dust destruction models in detail. © 2013. The American Astronomical Society. All rights reserved.