{
  "bibcode": "2012GCN.13325....1M",
  "body": "A. N. Morgan (UC Berkeley) reports:\n\nWe observed the field of GRB 120521C (Baumgartner et al., GCN 13318)\nwith the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations\nbegan at 2012-May-22 03h52m27s UT, ~4.5 hours after the Swift trigger.\n In  mosaics (effective exposure time of 1568 s) taken simultaneously\nin the J, H, and Ks filters, we do not detect any source within the\nenhanced XRT error circle (Beardmore et al. GCN 13324).\n\npost burst\nt_mid (hr) exp.(hr) filt  U. Limit (3 sig)\n4.99      0.44     J     > 18.5\n4.99      0.44     H     > 17.6\n4.99      0.44     Ks    > 16.0\n\nAll magnitudes are given in the Vega system, calibrated to 2MASS. No\ncorrection for Galactic extinction has been made to the above reported\nvalues.",
  "circularId": 13325,
  "createdOn": 1337665477000,
  "email": "qmorgan@gmail.com",
  "subject": "GRB 120521C: PAIRITEL NIR Upper Limits",
  "submitter": "Adam Morgan at U.C. Berkeley  <qmorgan@gmail.com>",
  "eventId": "GRB 120521C"
}