{
  "bibcode": "1999GCN...197....1T",
  "body": "S. E. Thorsett (Princeton University) and David W. Hogg (Institute for\nAdvanced Study) report:\n\nSN1999E is a bright (V=16) supernova discovered on Jan 15.276 (Perez\net al, IAUC 7089).  The supernova was not visible on 1998 Jul 29.046.\nIt is at redshift 0.025 (Filippenko et al, IAUC 7090), and is quite\nluminous, with M_V<-19.4 (H_0 = 65 km s^-1 Mpc^-1, Jha et al, IAUC\n7090).  The spectrum is similar to a spectrum of SN1997cy, the most\nluminous supernova known (M_V<=-20.06), taken about 4 months after\ndiscovery (Capellarro et al, IAUC 7091).  It is also similar in some\nrespects to the luminous SN1998bw (Filippenko et al, IAUC 7091).\n\nSN1998bw has been identified with GRB980425 (e.g., Sadler et al, IAUC\n6901).  SN1997cy has been associated with GRB970514 (Woosley et al,\nApJ, submitted, and http://xxx.lanl.gov/abs/astro-ph/?9806299).\n\nIn the five months between 1998 Jul 29 and 1999 Jan 15, BATSE observed\n97 GRBs (Meegan et al,\nhttp://www.batse.msfc.nasa.gov/data/grb/catalog/).  One of these, GRB\n980910 (BATSE trigger 7077), is coincident with the position of\nSN1999E, with a separation of 4.8 deg (the GRB position is uncertain\nto 6.8 deg).  We note that this GRB occurred just over 4 months before\nthe SN discovery, in agreement with the rough SN age, and propose that\nthe GRB and SN may be associated.\n\nIt is difficult to estimate a meaningful a posteriori likelihood of a\nchance coincidence.  The 97 GRBs have statistical error circles that\ncover 6766 deg^2, or about 16 percent of the sky, giving a 1/6 chance\nof accidental association.  However, only 31 GRBs fall between 3 and 5\nmonths before the SN discovery. If further observations of the SN\nlightcurve and spectrum allow a tighter constraint on the SN explosion\ntime, by comparison with the late-time properties of SN1998bw and\nSN1997cy, confidence in the association could be greatly improved.\nThe existence of one very good SN-GRB identification (SN1998bw) and\nnow two weaker associations (SN1998cy and 1999E) strongly suggests\nthat a significant fraction of GRBs are caused by peculiar supernovae.",
  "circularId": 197,
  "createdOn": 916961532000,
  "email": "hogg@ias.edu",
  "subject": "Possible identification of SN1999E with GRB980910",
  "submitter": "David W. Hogg at Institute for Advanced Study  <hogg@ias.edu>",
  "eventId": "GRB 980910"
}