{
  "bibcode": "2020GCN.26689....1H",
  "body": "R. Hamburg (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:\n\n\"At 01:45:51.89 UT on 9 January 2020, the Fermi Gamma-Ray Burst Monitor\n(GBM) triggered and located GRB 200109A (trigger 600227156 / 200109074),\nwhich also triggered the Swift/BAT approximately 25 s later\n(Melandri et al. 2019, GCN 26678). The Fermi GBM Final Real-time\nLocalization (GCN 26677) is consistent with the Swift position.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 57\ndegrees.\n\nThe GBM light curve shows a complex structure with a duration (T90) of\nabout 41 s (50-300 keV). The time-averaged spectrum from T0-0.8 s to\nT0+41.2 s is best fit by a power law function with an exponential\nhigh-energy cutoff.  The power law index is -0.98 +/- 0.08 and the\ncutoff energy, parameterized as Epeak, is 449 +/- 109 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(6.9 +/- 0.6)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0-0.7 s in the 10-1000 keV band\nis 2.3 +/- 0.2 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support\nPage:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"",
  "circularId": 26689,
  "createdOn": 1578597729000,
  "email": "rkh0007@uah.edu",
  "subject": "GRB 200109A: Fermi GBM observation",
  "submitter": "Rachel Hamburg at UAH  <rkh0007@uah.edu>",
  "eventId": "GRB 200109A"
}