TITLE: GCN CIRCULAR NUMBER: 11552 SUBJECT: GRB 110106B: early optical and near-IR observations DATE: 11/01/11 11:38:30 GMT FROM: Javier Gorosabel at IAA-CSIC J. Gorosabel, A.J. Castro-Tirado, M. Jelinek (IAA-CSIC, Granada), P. Kubanek (U. Valencia & IAA-CSIC, Granada), M. Visus, R. Tata (IAC, Obs. del Teide, Tenerife), A. Sota (OSN, Granada), S. Mottola, C. Faber (DLR, German Aerospace Center, Berlin), report on behalf of a larger collaboration: "We have carried out VRIH-band observations of the GRB 110106B XRT error circle (Sbarufatti et al. GCN Circ. 11525) using the 0.6m BOOTES2, 1.23m CAHA, the 1.5m OSN, the 0.82m IAC80 and the 1.5m TCS telescopes, as follows: Telescope Date Jan.2011 Post-GRB-time Filter Lim.Mag. (UT) (min) (3sigma) ------------------------------------------------------------------------------------------- 0.6m BOOTES2 6.90041-6.90212 10.3-12.8 R 16.5 1.23m CAHA 6.90179-6.91123 12.3-25.9 R 20.4 1.5m OSN 6.90258-6.91564 13.4-32.2 I 21.0 1.23m CAHA 6.91184-6.96185 26.8-98.8 V 20.5 IAC80 6.91533-6.92520 31.8-46.0 R 20.3 1.5m TCS 6.94378-6.96465 72.8-102.8 H 18.0 -------------------------------------------------------------------------------------------- No optical object is detected coincident with the optical afterglow position (Levan et al. GCN Circ. 11534, Berger et al. GCN Circ. 11540) down to the limiting magnitudes (Vega system) displayed in the above table."