TITLE: GCN CIRCULAR NUMBER: 15797 SUBJECT: GRB 140206A: T100 observations DATE: 14/02/06 19:34:14 GMT FROM: Eda Sonbas at NASA/GSFC E. Sonbas (Adiyaman Univ.), T. Guver (Istanbul Univ.), U. Temiz (Cukurova Univ.), E. Gogus (Sabanci Univ.), M. Kocak (TUG), O. Erece (Akdeniz Univ.), Z. Eker (Akdeniz Univ.) report on behalf of a larger collaboration We observed the field of Swift GRB 140206A (Lien et al., GCN#15784) with the 1.0 meter T100 telescope (Bakirlitepe, TUBITAK National Observatory, Turkey), starting February, 06, 16:33:24 UT (~ 9.268 hours after the trigger). Observations were carried out in the R filter under good weather conditions. The afterglow is clearly detected in 300 s in the R band images at a position that is consistent with Oksanen et al. GCN#15786 and Oates et al., GCN#15787 Using USNO-B1 star USNO-B1 1567-0128093 (R.A.=9:41:23.33, Dec=+66:44:32.31) in the field, the magnitudes of the OT were estimated as follows; t-t0 (hr) exp.(s) filt mag err (+/-) 9.590 300 R 18.65 0.05 9.689 300 R 18.77 0.06 9.788 300 R 18.75 0.06 10.380 300 R 18.89 0.06 Further observations using the same filter are ongoing. We are grateful to TUBITAK National Observatory for prompt scheduling the observations and technical support.