{
  "format": "text/plain",
  "eventId": "sb25043004",
  "circularId": 40287,
  "submitter": "SVOM_group <svomgroup@bao.ac.cn>",
  "body": "Y. Liang (PMO), W. Zheng (Berkeley), O. Godet, S. Guillot (IRAP), C. Plasse, J. T. Palmerio (CEA)\non behalf of the SVOM mission team.\n\n\nSVOM/ECLAIRs triggered and located the X-ray transient sb25043004 (SVOM burst-id sb25043004) starting at 2025-04-30T10:40:57.1 UTC (Tb).\n\nThe following trigger information was received on the ground with low latency by the SVOM VHF Alert Network.\n\nThe source was only detected by the Image Trigger (IMT), which produced a sequence of 3 alerts. IMT provided the alert with the best signal-to-noise-ratio (SNR) of 8.96 in the [5-8] keV energy band over a time window of 327.68 seconds starting at Tb.\n\nThe localization of the best alert is R.A., Dec. 272.104, -38.6635 degrees:\nR.A. (J2000) = 18h08m25.13s\nDec. (J2000) = -38d39m48.60s\nwith a 90% confidence level (C.L.) radius of 8.82 arcmin (including systematic error of 2 arcmin added in quadrature).\n\nSVOM slewed to the source.\n\nMXT began observing the field after the slew. The analysis of the recorded images will be published in a future circular gathering information on the follow-up of the SVOM optical instruments.\n\nVT began observing the field after the slew. The analysis of the recorded images will be published in a future circular gathering information on the follow-up of the SVOM optical instruments.\n\nThe Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe.\n\nThe Burst Advocate (BA) on shift for this burst is Weikang Zheng: weikang@berkeley.edu.\nPlease contact the BA by email if you require additional information regarding the SVOM follow-up of this burst.\n",
  "subject": "SVOM/sb25043004: SVOM  detection of a X-ray transient",
  "submittedHow": "web",
  "bibcode": "2025GCN.40287....1L",
  "createdOn": 1746013146595
}