TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4478 SUBJECT: GRB 060110: Mitsume optical observations DATE: 06/01/11 04:30:40 GMT FROM: Nobuyuki Kawai at Tokyo Tech K. Yanagisawa (OAO/NAOJ), H. Toda and N. Kawai (Tokyo Tech) report on behalf of the Mitsume collaboration: "We have observed the field of GRB 060110 (Zane et al. GCN 4463, Parsons et al. GCN 4477) with the three-color Mitsume 50 cm telescopes at Okayama, Japan in g', Rc, and Ic bands starting at 9:58 UT (T_burst+2.0h) until 10:12 UT (T_burst+2.2h) for an effective exposure of 10 min (60sec x 10). The observing condition was not good due to clouds and the position near the moon. In the co-added image, we could not confirm the OT candidate (Torii GCN 4468; Bloom et al. GCN 4471, Rujopakarn et al. GCN 4472, Tanvir et al. GCN 4473, Wozniak et al. GCN 4474) down to the following 3-sigma magnutude limits: g': 17.6 Rc: 18.0 Ic: 17.3 The images obtained at Okayama can be viewed at http://bragi.oao.nao.ac.jp/support/telescope/grb50/images/GRB060110A.pdf"