L183 (=L134N) revisited : the physical conditions in the main prestellar core
Résumé
We continue the detailed study of L183 with the observations of N-bearing species (N2H+, N2D+, NH3) which allow to trace the physical conditions in the most inner parts of prestellar cores where standard tracers are completely depleted. With the help of our new 1D Monte-Carlo code which treats the hyperfine structure of N2H+ in detail, we are able to trace the density, temperature and N2H+/N2D+ abundance profiles of the core and also its kinematical properties. Depletion of N2H+, very cold gas and a peculiar rotational pattern are revealed.