Supernova 2002ic: The collapse of a stripped-envelope, massive star in a dense medium?

We revisit the case of SN 2002ic, which recently revived the debate about the progenitors of Type Ia supernovae (SNe Ia) after the claim of the unprecedented presence of hydrogen lines over a diluted SN Ia spectrum. As an alternative to the previous interpretation, we suggest that SN 2002ic actually was a Type Ic SN, the core collapse of a massive star that lost its hydrogen and helium envelope. In this scenario the observed interaction with a dense circumstellar material (CSM) is the predictable consequence of the intense mass loss of the progenitor and/or of the presence of a gas-rich environment. With this view we establish a link between energetic SNe Ic and highly interacting SNe IIn and add some credits to the proposed association of some SNe IIn with gamma-bursts (GRBs).