{
  "bibcode": "1997GCN....20....1C",
  "body": "GRB 971227                                                             #020\n\nA. J. Castro-Tirado and J. Gorosabel, Laboratorio de Astrofisica Espacial y\n   Fisica Fundamental, Madrid\nJ. Greiner, Astrophysikalisches Institut, Potsdam\nM. R. Zapatero-Osorio, Instituto de Astrofisica de Canarias, Tenerife\n   and\nE. Costa, Istituto di Astrofisica Spaziale, Frascati (on behalf of the \n   BeppoSAX team)\n\nReport: following the detection of GRB 971227 by BeppoSAX and BATSE (IAUC \n6796, 6798), R-band images were obtained by Y. Aguilar and R. Kohley \n(Sternwarte der Universitat, Bonn) with the 2.2-m CAHA telescope (+CAFOS) at \nthe German-Spanish Calar Alto Observatory. Only the image taken on Dec 27.91 \nincludes the entire error box of 1SAX J1257.3+5924, presumably the GRB 971227\nX-ray afterglow (IAUC 6797).  An object with R = 19.5 (preliminary magnitude) \nat the edge of the 16' field of view and inside the 1SAX J1257.3+5924 error \nbox, is seen on the Dec 27.91 image, but it is not present on the images \ntaken on Dec 30.16 at Loiano (see below), above a limiting magnitude R = 20.5.\nIts position is AR(2000) = 12 57 10.6, Dec(2000) = +59 24 43 (+/- 3\"). \nAn identification-chart can be obtained via anonymous ftp at laeff.esa.es \nunder /pub/users/ajct/grb971227.  Deeper observations are encouraged in order \nto confirm whether this is the optical counterpart of GRB 971227.\n\nC. Bartolini, A. Guarnieri, M. Lolli, A. Piccioni and F. Zavatti, Universita \ndi Bologna, \n\nCommunicate: the object proposed by Castro-Tirado et al (this Circ.) is\nundetectable on our R frames on Dec 30.16 which were taken at the 1.5m \ntelescope of the Bologna Astronomical Observatory in Loiano.  The object\nwas therefore fainter than R=20.5 (mag limit of the images, preliminary \nvalue).  Data reduction is in progress.  Deeper imaging is highly recommended.",
  "circularId": 20,
  "createdOn": 0,
  "email": "circulars@gcn.nasa.gov",
  "subject": "Untitled",
  "submitter": "circulars@gcn.nasa.gov"
}