{
  "eventType": [
    "GRB",
    "X-ray Transient"
  ],
  "format": "text/plain",
  "eventId": "GRB 261024D",
  "subject": "GRB 261024D: NuSTAR detection of prompt emission",
  "circularId": 46051,
  "body": "G. Waratkar (Caltech) and B. Grefenstette (Caltech) report on behalf of the NuSTAR Search for INteresting Gamma-ray Signals (SINGS) working group:\n\nThe NuSTAR SINGS working group reports the detection of prompt emission from the long-duration GRB 261024D in both the NuSTAR CsI anti-coincidence shields. This GRB was identified through a blind search using the CsI shield rates. Details of the search algorithm will be described in a future paper.\n\nThe NuSTAR SINGS algorithm triggered at 2026-10-24T21:33:05.000 UTC shows a detection of GRB 261024D, also detected by SVOM-GRM (GCN Notices), KONUS-Wind (GCN Notices), and AstroSat-CZTI (GCN 46040).\n\nThe NuSTAR CsI shield data are recorded at 1 Hz. We detect a single-peaked burst lasting for about 10-s. The peak count rate is ~1500-cps with a baseline rate of ~1000-cps during this time period. We do not see any evidence in the signal above 100 keV in the CZT detectors.\n\nThe SVOM-GRM localization at RA = 209.99, Dec = -47.33 implies an offset from the NuSTAR boresight of 100-deg and an offset from the geocenter of 102-deg.\n\nLightcurves and analysis for this GRB can be found here:\nhttps://nustarsoc.caltech.edu/NuSTAR_Public/grbs/reports/2026/261024D \n\nInformation on NuSTAR SINGS can be found here: \nhttps://nustarsoc.caltech.edu/NuSTAR_Public/grbs/     \n\nNuSTAR is a NASA Small Explorer mission led by Caltech and managed by JPL for NASA's Science Mission Directorate in Washington.\n",
  "createdOn": 1793051929782,
  "submitter": "Gaurav Waratkar at Caltech <gauravwaratkar@iitb.ac.in>",
  "submittedHow": "web"
}