An Hst Study of the Supernovae Accompanying Grb040924 and Grb041006

We present the results from a Hubble Space Telescope/ACS study of the supernovae associated with gamma-ray bursts 040924 (z = 0.86) and 041006 (z = 0.71). We find evidence that both GRBs were associated with a SN1998bw-like supernova dimmed by ∼ 1.5 and ∼ 0.3 magnitudes, respectively, making GRB040924 the faintest GRB-associated SN ever detected. We study the luminosity dispersion in GRB/XRF-associated SNe and compare to local Type Ibc supernovae from the literature. We find significant overlap between the two samples, suggesting that GRB/XRF-associated SNe are not necessarily more luminous nor produce more Ni than local SNe. Based on the current (limited) datasets, we find that the two samples may share a similar Ni production mechanism. Subject headings: gamma rays: bursts radiation mechanisms: nonthermal supernova: individual