Twelve type II-P supernovae seen with the eyes ofSpitzer

Context. Core-collapse supernovae (CC SNe), especially those of type II-plateau (II-P), are thought to be important contributors to cosmic dust production. The most obvious indicator of newly-formed and/or pre-existing dust is the time-dependent mid-infrared (MIR) excess coming from the environment of SNe. In the past few years several CC SNe were monitored by the Spitzer Space Telescope in the nebular phase, hundreds of days after explosion. On the other hand, only a few of these objects have been analyzed and published to date.