A Model of the 10 Micrometer Silicate Feature in the Spectra of BN-like IR-Point Sources (Mitteilungen der Universitäts-Sternwarte zu Jena Nr. 150)

A model representing the profile of the silicate absorption band at 9.8 μm in the spectra of BECKLIN -NEUGEBAUER objects has been developed, solving the equation of radiative transfer. The model based on the condition of radiative equilibrium, on an analytical temperature distribution and on the assumption of constant density in the circumstellar shell allows the evaluation of the optical depth in the band's centre and the investigation of the effect of the temperature variation at the inner boundary of the envelope. The optical depth in the band's centre ist calculated for the BN point source.