TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4040 SUBJECT: GRB 050922C: break in the lightcurve DATE: 05/09/26 20:13:40 GMT FROM: Brian Lindgren Jensen at U.of Copenhagen Johan P. U. Fynbo, Brian L. Jensen, Páll Jakobsson, Jens Hjorth, Jesper Sollerman, José María Castro Cerón (DARK, NBI), Karianne Holhjem (NOT, La Palma), Ricardo Salinas (Universidad de Concepción, Chile) report: We have obtained further imaging of the afterglow of GRB 050922C (GCN 4011, 4012, 4013) using the ALFOSC at the Nordic Optical Telescope on La Palma and DFOSC at the Danish 1.5m telescope at La Silla, Chile. We find that the early decay slope of about 1 (GCN 4012) extends to less than a day post burst, after which the decay slope steepens to about alpha=1.7+-0.3. Further observations are planned. A preliminary lightcurve can be seen at: http://www.astro.ku.dk/~brian_j/grb/grb050922.830/