{
  "bibcode": "2010GCN.10577....1U",
  "body": "SUBJECT: GRB100401A, GROND Upper Limits\n\nA. Updike (Clemson University), A. Rau, P. Afonso and J. Greiner (all\nMPE Garching) report on behalf of the GROND team:\n\nWe observed the field of GRB 100401A (Cummings et al., GCN #10567,\nGoldstein and Gruber, #GCN 10568)  simultaneously in g'r'i'z'JHK with\nGROND (Greiner et al. 2008,PASP 120, 405), mounted at the 2.2m ESO/MPI\ntelescope at La Silla Observatory (Chile).\n\nObservations started on 2010, April 3, at 09:21 UT, 2.09 days after the\nburst, and consisted of 20 min in JHK and 24.6 min in g'r'i'z'. A second\nepoch was obtained on 2010, April 4, at 09:09 UT, 2.99 days after the burst.\n\nImage subtraction of the two epochs does not reveal a variable source,\ndown to the following 1st epoch limiting magnitudes (all in AB system):\n\ng' > 23.7\nr' > 23.9\ni' > 23.4\nz' > 23.4\nJ  > 21.8\nH  > 21.4\nK  > 20.3\n\nThese magnitudes were obtained using 2MASS field stars and GROND\nzero-points as reference, and are not corrected for the Galactic\nextinction due to the reddening of E(B-V) = 0.29 mag in the direction of\nthe burst (Schlegel et al. 1998).",
  "circularId": 10577,
  "createdOn": 1270424500000,
  "email": "pafonso@mpe.mpg.de",
  "subject": "GRB100401A: GROND Upper Limits",
  "submitter": "Paulo M. J. Afonso at MPE  <pafonso@mpe.mpg.de>",
  "eventId": "GRB 100401A"
}