TITLE: GCN CIRCULAR NUMBER: 8085 SUBJECT: GRB 080810: KANATA optical-NIR observation, update DATE: 08/08/10 19:35:44 GMT FROM: Makoto Uemura at Hiroshima U M. Uemura, M. Yamanaka, Y. Ikejiri, K. Sakimoto, T. Ohsugi, K.S. Kawabata, and A. Arai, report on behalf of the KANATA GRB team: We continue the observation of GRB 080810 with the KANATA 1.5-m telescope. We obtained V, J, and Ks-band images of the field of the afterglow using TRISPEC. The latest observation shows: time(UT) mag. err exposure time Aug. 2008 10.78444 18.92V 0.05 123sec * 10 10.78479 17.53J 0.31 72sec * 10 The light curve we obtained can be described with a simple power-law decay between 420 and 20000 sec after the GRB trigger, without an apparent break. The power-law index is calculated to be 1.21+/-0.02. The index is slightly, but significantly larger than that reported in GCN 8084, implying a possible break around the very early or very late phase of our observation period. Further monitoring is encouraged.