Cometary bodies in the circumstellar disk around β Pictoris

The IRAS star β Pictoris is still the only one around which a disk made of both dust and gas has been detected. Spectroscopic observations of β Pic have revealed that some metallic absorption lines present redshifted additional components which strongly variate with time. This has been interpreted as the result of the infall of small evaporating cometary-like bodies toward the star. To improve this model, a theoretical description of such an event has been purchased. Numerical simulations of such infalling bodies have been able to reproduce quite faithfully the observed behaviour of some metallic ions, and we have explained the observed difference between these behaviours by means of radiation pressure. Some constraints on the orbits of the bodies have been deduced by through the simulations which should be related to a possible interpretation concerning β Pic's disk