{
  "bibcode": "2008GCN..7630....1O",
  "body": "M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA)\nK. Yamaoka, S. Sugita (Aoyama Gakuin U.),\nT. Enoto (Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN),\nT. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata\n(Hiroshima U.), M. Tashiro,\nY. Terada, Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami (Saitama U.),\nK. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi,\nH. Tanaka, R. Hara (Univ. of Miyazaki), , S. Hong (Nihon U.),\non behalf of the Suzaku WAM team, report:\n\nJ. Tueller (GSFC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),\nA. P. Beardmore (U Leicester), J. Cummings (GSFC/UMBC), E. Fenimore (LANL),\nN. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),\nK. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC),\nG. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU)\n(i.e. the Swift-BAT team):\n\nreport:\n\nWe performed the Suzaku/WAM and Swift/BAT joint fit spectral\nanalysis of GRB 080413A (Swift/BAT trigger #309096; Beardmore et al., \nGCN 7594).  The time interval of the spectral data for each \ninstrument is chosen from T0(WAM)-1 to T0(WAM)+22 sec where\nT0(WAM) is the trigger time of WAM at  02:54:18.648 UTC.  \nThis time interval includes the initial two peaks, but not \nthe relatively soft third peak around T0(WAM)+45 sec which \nis clearly visible in the BAT data (Tueller et al., GCN 7604).  \nThe energy ranges which we used in the joint spectral analysis\nare 13-150 keV and 150-1000 keV for Swift/BAT and Suzaku/WAM\nrespectively.  The spectral data of two instruments are fit\nwith the spectral model multiplied by the constant factor to\ntake into account the systematic uncertainties in the response\nmatrices of each instrument.\n\nThe spectrum is well fit with a power-law with exponential cutoff\nmodel (dN/dE ~ E^{alpha} * exp(-(2+alpha)*E/Epeak)).  The constant\nfactors of each instrument agree within 20%.  No systematic residual\nfrom the best fit model is seen in the spectral data of each instrument.\nThe best fit spectral parameters are: alpha = -1.2 +- 0.1 and\nEpeak = 170 (-40/+80) keV (chi2/dof = 75/73).  The energy fluence\nin the 15-1000 keV band calculated by a power-law with exponential\ncutoff model for this 23 sec interval is 4.8 (-1.2/+0.4) x 10^-6 erg/cm2\n(assuming the constant factor of the BAT is fixed to 1).\n\nAssuming z = 2.433 (Thoene et al., GCN 7602) and a standard \ncosmology model with H_0 = 71 km/s/Mpc, Omega_M = 0.27, \nOmega_\\Lambda = 0.73, the isotropic energy release is \nE_iso ~8x10^52 erg in 1 keV to 10 MeV at the GRB rest frame.   \n\nAll the quoted errors are at the 90% confidence level.",
  "circularId": 7630,
  "createdOn": 1208555405000,
  "email": "takanori.sakamoto-1@nasa.gov",
  "subject": "GRB 080413A: Suzaku/WAM and Swift/BAT joint spectral analysis",
  "submitter": "Takanori Sakamoto at NASA/GSFC  <takanori.sakamoto-1@nasa.gov>",
  "eventId": "GRB 080413A"
}