Optical Bumps in Cosmological GRBs as Supernovae


From both photometric and broadband spectral monitoring of γ-ray burst (GRB) lightcurve ``bumps,’’ particularly in GRB011121, a strong case grew for a supernova (SN) origin. The GRB-SN connection was finally solidified beyond a reasonable doubt with the discovery that the bump in GRB030329 was spectroscopically similar to a bright Type Ic SN. In light of this result, I re-assess the previous SN bump claims and conclude that: 1) the distribution of GRB-SN bump peak magnitudes is consistent with the local Type Ib/c SNe peak distribution and 2) the late-time bumps in all long-duration GRBs are likely supernovae.

IAU Colloq. 192: Cosmic Explosions, On the 10th Anniversary of SN1993J