Radiation transfer in dense interstellar clouds

Summary The scattering properties of interstellar dust in the far ultraviolet as derived from the observations are reviewed. The transfer of ultraviolet radiation within a spherically symmetric inhomogeneous cloud is analysed using the method of successive scattering. The effects of different assumptions, both on the albedo and asymmetry factor of interstellar dust, and also of the extinction law on UV radiation penetration into clouds are studied. The results are used to determine the lifetime against photodestruction of interstellar formaldehyde in dense clouds. Paper presented at the 2° Convegno Nazionale di Fisica Cosmica, held at L'Aquila, 29 May–2 June 1984.