{
  "bibcode": "2017GCN.20652....1R",
  "body": "O.J. Roberts (USRA/NASA) and C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 01:08:38.08 UT on the 9th of February 2017,\nthe Fermi Gamma-Ray Burst Monitor triggered and\nlocated GRB 170209A (trigger 508295323 / 170209048),\nfor which MASTER reported an OT in follow-up \nobservations of the reported GBM location region\n(Podesta et al. 2017, GCN 20650). The on-ground \ncalculated location using the GBM trigger data is,\n\nRA = 113.40, DEC = -49.64 (J2000 degrees), equivalent\nto J2000 7h 33m, -49d 38',\n\nwith an uncertainty of 3.22 degrees (radius, 1-sigma\ncontainment, statistical only; there is additionally\na systematic error which we have characterized as a\ncore-plus-tail model, with 90% of GRBs having a 3.7 deg.\nerror and a small tail suffering a larger than 10 deg.\nsystematic error [Connaughton et al. 2015, ApJS, 216, 32]).\n\nThe angle from the Fermi LAT boresight at the GBM trigger\ntime is 120 degrees.\n\nThe GBM light curve consists of a long GRB with two bright\nepisodes of emission over a duration (T90) of about 40 s\n(50-300 keV). The time-averaged spectrum from T0+0 s to\nT0+40.0 s is best fit by a power law function with an\nexponential high-energy cutoff.  The power law index is\n-0.95 +/- 0.07 and the cutoff energy, parameterized as\nEpeak is 132 +/- 9 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(9.34 +/- 0.37)E-06 erg/cm^2. The 1-sec peak photon flux\nmeasured starting from T0+1.9 s in the 10-1000 keV band\nis 12.6 +/- 0.4 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 20652,
  "createdOn": 1486679203000,
  "email": "oliver.roberts@nasa.gov",
  "subject": "GRB 170209A: Fermi GBM Detection",
  "submitter": "Oliver J Roberts at USRA/NASA  <oliver.roberts@nasa.gov>",
  "eventId": "GRB 170209A"
}