Interstellar grain composition and the infrared spectrum of OH 26.5 + 0.6

Abstract

Theoretical infrared spectra in the range 1 to 35 µm are compared for cellulose and various silicate materials. The dusty object OH 26.5 + 0.6 is modelled for illustrative purposes, and the full radiative transport is solved subject to the constraint of radiative equilibrium. Our results appear to exclude cellulose as a viable candidate for the grain material. Meteoritic silicates provide a satisfactory fit to the 9.7 µm feature.