{
  "bibcode": "2006GCN..4938....1F",
  "body": "E. Fenimore, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley,\non behalf of the HETE Science Team;\n\nM. Arimoto, T. Donaghy, M. Galassi, C. Graziani, N. Ishikawa,\nA. Kobayashi, J. Kotoku, M. Maetou, M. Matsuoka, Y. Nakagawa,\nT. Sakamoto, R. Sato, T. Shimokawabe, Y. Shirasaki, S. Sugita,\nM. Suzuki, T. Tamagawa, K. Tanaka, and A. Yoshida, on behalf of the\nHETE WXM Team;\n\nN. Butler, G. Crew, J. Doty, G. Prigozhin, R. Vanderspek,\nJ. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga,\nR. Manchanda, G. Pizzichini, and S. Gunasekera, on behalf of the HETE\nOperations and HETE Optical-SXC Teams;\n\nM. Boer, J-F Olive, A. Pelangeon, J-P Dezalay, and K. Hurley, on behalf\nof the HETE FREGATE Team;\n\nreport:\n\nAt 06:41:42 UTC on March 31, 2006 HETE-2 detected a long, bright\nand soft event at the extreme edge of the WXM field of view.\n\nGround analysis yields an error box centered at (J2000):\n(RA,DEC) (deg) = 233.444d  -15.235d (15h 33m 47s  -15d 14' 04\")\n\nwith the following corners (J2000):\n(RA,DEC) (deg) =   233.792   -15.396\n(RA,DEC) (deg) =   233.081   -15.456\n(RA,DEC) (deg) =   233.096   -15.072\n(RA,DEC) (deg) =   233.806   -15.015\n\nThe error box area is 944 square arc minutes.\n\nThe time profile shows a rise time of ~10 seconds and a fall time\nof >100s, with little obvious spectral evolution. Neither a power-law\nnor a blackbody yields an acceptable spectral fit.\n\nThis event is unusual. It resembles an X-ray burst from a galactic binary,\nyet its location at high galactic latitude, its long duration without the\nexpected spectral evolution from photospheric expansion, and the failure\nof a blackbody spectral fit all argue against this interpretation.\n\nOn the other hand, it is unusually bright for an X-ray flash, and the\nfailure of a power law fit argues against this interpretation.\n\nThere is  a known x-ray source (1RXS J153521.7-150420) in the error box,\nbut this is not unlikely for a box this large.\n\nA light-curve of the event is given at http://space.mit.edu/HETE/Bursts/GRB060331/\n\nWe urge further observations of this unusual event at all wavelengths.\n\n[GCN OPS NOTE(31mar06): Per author's request, the URL was corected; see \nGCN Circ 4939.]",
  "circularId": 4938,
  "createdOn": 1143820817000,
  "email": "atteia@ast.obs-mip.fr",
  "subject": "H4043, an unusual high-energy transient observed by HETE",
  "submitter": "Jean-Luc Atteia at Lab d Astrophys.,OMP,Toulouse  <atteia@ast.obs-mip.fr>"
}