TITLE: GCN CIRCULAR NUMBER: 23713 SUBJECT: GRB 190114B: NOT optical counterpart DATE: 19/01/15 12:53:20 GMT FROM: Jonatan Selsing at DARK/NBI J. Selsing (DAWN/NBI and DAWN/DTU), A. de Ugarte Postigo (HETH/IAA-CSIC and DARK/NBI), and S. Dyrbye (NOT), report on behalf of a larger collaboration: We have observed the optical afterglow of GRB GRB190114B (Siegel et al., GCN 23686; Goad et al., GCN 23691) at the 2.5-m Nordic Optical Telescope (NOT). We have obtained an griz-band imaging sequence using the ALFOSC instrument, with 3x300s exposure in gri-band and 5x200s in z-band. Observations began at 01:51:42 UT, on the night of the 14th of January, 6.3 hr after the BAT trigger.  In the images we confirm the detection of the optical counterpart in Fernandez-Garcia et al. (GCN 23694) and Pozanenko et al. (GCN 23696) and report further fading. The source is located at: RA (J2000.0) = 11:39:29.823 DEC (J2000.0) = +18:53:28.19 with the astrometric solution calibrated against the 2MASS catalog.  We calibrate the photometric zeropoints against the Pan-STARRS catalog and calculate the following magnitudes for the optical counterpart: g = 21.61 +- 0.13 AB mag  r = 21.15 +- 0.09 AB mag  i = 20.96 +- 0.04 AB mag  z = 20.59 +- 0.08 AB mag