{
  "bibcode": "2013GCN.15531....1X",
  "body": "D. Xu (DARK/NBI), H.-B. Niu, J.-Z. Liu, G.-J. Feng, C.-H. Bai, A.\nEsamdin, L. Ma (XAO) report:\n\nWe observed the fields of the three afterglow candidates of GRB\n131127B (von Kienlin, GCN 15528; Singer & Kasliwal, GCN 15524;\nGolenetskii et al., GCN 15530), using the 1m telescope located on Mt.\nNanshan, Xinjiang, China. Observations started at 11:37:34 UT on\n2013-11-28, (i.e., 21.42 hr after the Fermi trigger) and a series of\nR-band frames were obtained.\n\nThe three optical afterglow candidates are clearly detected in their\nstacked images.\n\nFor the one dubbed iPTF13ecv, we measure its magnitude\nm(R)=18.66+/-0.14, calibrated with two nearby SDSS stars and using the\nLupton (2005) transformation. This magnitude is basically consistent\nwith the value reported in Singer & Kasliwal (GCN 15524), indicating\nthat its significant fading is ruled out.\n\nFor the other two dubbed iPTF13ect and iPTF13ecu, given that they are\nvery close to the cores of the galaxies and not well resolved in our\nimages, we are not able to put good constraints on their magnitudes at\nthe moment.",
  "circularId": 15531,
  "createdOn": 1385645105000,
  "email": "dong.dark@gmail.com",
  "subject": "GRB 131127B: Nanshan optical observations",
  "submitter": "Dong Xu at DARK/NBI  <dong.dark@gmail.com>",
  "eventId": "GRB 131127B"
}