{
  "bibcode": "2013GCN.14453....1M",
  "body": "A. N. Morgan (UC Berkeley) reports:\n\nWe observed the field of GRB 130427A (Maselli et al., GCN 14448) with the\n1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations began at\n2013-Apr-27 07h59m24s UT, 11.45 minutes after the Swift Trigger.  In\npreliminary mosaics (consisting of 75 ~8 second images for a total\neffective exposure time of 9.75 minutes) taken simultaneously in the J, H,\nand Ks filters, we detect the optical afterglow (Elenin et al., GCN 14450;\nPerley, GCN 14451; Melandri et al., GCN 14452).\n\nThe preliminary photometry yields:\n\npost burst\nt_mid (hr) exp.(m)   filt  mag   m_err\n0.36       9.75      J     12.13  0.03\n0.36       9.75      H     11.75  0.04\n0.36       9.75      Ks    11.02  0.08\n\nObservations continued until the source passed beyond telescope limits. All\nmagnitudes are given in the Vega system, calibrated to 2MASS. No correction\nfor Galactic extinction has been made to the above reported values.",
  "circularId": 14453,
  "createdOn": 1367056061000,
  "email": "qmorgan@gmail.com",
  "subject": "GRB 130427A: PAIRITEL NIR Detections",
  "submitter": "Adam Morgan at U.C. Berkeley  <qmorgan@gmail.com>",
  "eventId": "GRB 130427A"
}