GCN Circular 4981
Daniel Kocevski, J. S. Bloom (UC Berkeley), and C. H. Blake (Harvard/ CfA), on behalf of a larger collaboration, report: "We began observations of GRB 060417 (Falcone et. al. GCN 4966) with the PAIRITEL 1.3m at 2006-04-18 05:25:34. UTC, 2hr32min after the GRB trigger. The transient reported by Falcone et al. (GCN 4966) is well detected in 300s mosaics simultaneously in JHKs bands, and is seen to fade between mosaics. A series of 13 simultaneous JHKs mosaics taken over 6 hours of observations shows a power law decline in J with a slope of about alpha = 1.11 +/- 0.10 ( F(t)~t^(-alpha) ). The decay slopes measured in H and Ks are consistent with the J band slope within error. This slope is consistent with that reported by Nysewander et al. (GCN 4971) and Cobb et al. (GCN 4972). No break was seen in the observed decay out to at least 08:09:31 UTC. An animated gif of the observations can be found at: http://lyra.berkeley.edu/~kocevski/GCN/GRB060418.gif This message may be cited.