Type Ibn supernova SN~2010al is explored to infer parameters of supernova and a circumstellar (CS) shell. The CS interaction model combined with the spectral model of 4600\AA\ blend suggests the explosion of a WR star with the energy of $(1-1.5)\times10^{ 51}$ erg inside a dense confined CS shell with the mass of $\sim0.1$\msun\ and kinetic energy of $\sim 10^{ 48}$ erg. The confined CS shell has been formed during the last 0.4 yr prior to the core collapse.
Categories: astro-ph.HE