Light-curve of GRB 060614

Light curve of the optical emission from GRB 060614. The circles represent the observed data. At the expected time (10-20 days after the GRB), there is no sign of rebrightening due to a supernova. The light curve after ~0.3 day (blue solid line) has been decomposed in the sum of two components: the afterglow (blue dotted line) and the host galaxy (blue short-dashed lines). There is no need for a supernova component: the green dot-dashed line is the brightest supernova allowed by our data. This is very faint, and for comparison the yellow long-dashed line shows the light curves of SN 1998bw, the proto-typical SN associated with a GRB. The inset displays a zoom around the maximum of the putative SN, with the green solid line showing the contribution from the brightest supernova allowed by our data.

This is very faint, and for comparison the yellow long-dashed line shows the light curves of SN 1998bw, the proto-typical SN associated with a GRB. The inset displays a zoom around the maximum of the putative SN, with the green solid line showing the contribution from the brightest supernova allowed by our data. Right: Light curve of the optical emission from GRB 060505. This gamma-ray burst was monitored with the Danish 1.5 m telescope, the Very Large Telescope and the Keck telescope over a period of 12 weeks, allowing te astronomers to detect the afterglow on the first night after the burst and thereafter obtain very strict upper limits on associated supernova emission. Thus neither GRB 060505 nor GRB 060614 were associated with significant supernova emission down to very faint limits hundreds of times less luminous than the archetypal SN 1998bw.