Problemi inversi in astrofisica
A Mathematical Model for a Contracting Interstellar Cloud
In this paper, we study a one-dimensional mathematical model for a contracting interstellar cloud, with a star inside. Existence and uniqueness of a positive solution are proved by means of the fixed point theorem. A time discretization procedure is given and the case of an expanding interstellar cloud is also considered.
Identification of a localized source in an interstellar cloud: an inverse problem
We study an inverse problem for photon transport in an interstellar cloud. In particular, we evaluate the position of a localized source , inside a nebula (for example, a star). We assume that the photon transport phenomenon is one-dimensional. Since a nebula moves slowly in time, the number of photons inside the cloud changes slowly in time. For this reason, we consider the so-called quasi-static approximation to the exact solution . By using semigroup theory, we prove existence and uniqueness...
Page 1