TITLE: GCN CIRCULAR NUMBER: 9128 SUBJECT: GRB 090410: GROND upper limits DATE: 09/04/14 16:18:34 GMT FROM: Jochen Greiner at MPI P. Afonso, T. Kruehler, A. Rau and J. Greiner (MPE Garching), report on behalf of the GROND team: GROND (Greiner et al. 2008, PASP 120, 405), the 7-channel imager mounted at the 2.2m ESO/MPI telescope at La Silla Observatory (Chile) started follow-up observations of GRB 090410 (Grupe et al. 2009, GCN #9122) on April 11, at 10:17 UTC (17.3 h after the burst). In addition, a second epoch of imaging was obtained, which started on April 12, 10:10 UTC. Observations were performed at high airmass (~2.5) and limited to a total of 4 min exposures in each J, H and K in both epochs because of Sun constraints. We do not detect any new object with respect to 2MASS inside the enhanced BAT error circle (Barthelmy et al. 2009, GCN #9123), and image subtraction between the two epochs does not reveal any obvious variable source. Upper limits from the first observation are as follows (all in the AB system): J > 19.1 mag H > 19.0 mag K > 18.1 mag The upper limits have been obtained using 2MASS field stars as reference. The given magnitudes are not corrected for the expected Galactic foreground extinction of E(B-V) of 0.05 mag.