{
  "eventId": "GRB 260307A",
  "createdOn": 1773398712905,
  "circularId": 43982,
  "submittedHow": "web",
  "format": "text/plain",
  "submitter": "Yuta Kawakubo at Aoyama Gakuin University <kawakubo@phys.aoyama.ac.jp>",
  "subject": "GRB 260307A: CALET Gamma-Ray Burst Monitor detection",
  "body": "Y. Shimizu (Kanagawa U), A. Yoshida, T. Sakamoto, S. Sugita, Y. Kawakubo (AGU),\nK. Yamaoka (Nagoya U), S. Nakahira (JAXA), Y. Asaoka (ICRR), S. Torii,\nY. Akaike, K. Kobayashi (Waseda U), T. Tamura (Kanagawa U),\nN. Cannady (GSFC/UMBC), M. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena)\nand the CALET collaboration:\n\nThe long GRB 260307A (Fermi GBM Final Real-time Localization: Fermi GBM team,\nGCN Circ. 43939; Glowbug gamma-ray detection: Cheung et al., GCN Circ. 43950;\nGECAM-B observation: Zao et al., GCN Circ. 43961) triggered the CALET Gamma-ray\nBurst Monitor (CGBM) at 11:27:56.49 UTC on 7 March 2026\n(https://cgbm.calet.jp/cgbm_trigger/flight/1456918069/index.html).\nThe burst signal was seen by all CGBM detectors. \n\nThe burst light curve shows a multi-peaked structure that starts\nat T+2.8 sec, peaks at T+5.2 sec, and ends at T+8.0 sec.\nThe T90 and T50 durations measured by the SGM data are 4.6 +/- 0.5 sec\nand 2.0 +/- 0.2 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\nhttps://cgbm.calet.jp/cgbm_trigger/ground/1456918069/\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University.\n"
}