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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19298 results found.

  1. GRB 261029A : SVOM/GWAC-F60 observations
  2. GRB 261029A: GECAM-B detection of a bright burst
  3. The EP-WXT trigger 01709321980 is likely a flaring star
  4. EP Alert 261030.22: Global MASTER-Net observations report
  5. GRB 261029A: WFST optical observations
  6. GRB 261029A: ULL-ASTRO-MASTER observations with LCO 1-m telescope at Siding Spring Observatory
  7. GRB 261029A: Ondrejov D50 optical observations, possible rebrightening
  8. GRB 261029A: Liverpool Telescope observations
  9. GRB 261029A: NuSTAR detection of bright prompt emission
  10. GRB 261029A: Optical detection with 60cm Panzhihua Telescope
  11. GRB 261029A: Fermi GBM Observation
  12. GRB 261029A: FRAM-ORM and FRAM-Auger optical afterglow light curve
  13. GRB 261029A: SVOM/GRM observation of a bright burst
  14. GRB 261029A: CALET Gamma-Ray Burst Monitor detection
  15. GRB261029A: Infrared fading detected with MDM/MIRAGE
  16. GRB 261029A: SVOM/VT optical observation
  17. GRB 261029B : AstroSat CZTI detection
  18. GRB 261029A / AT2026ahaw: r- and i-band optical follow-up with the PKU 60cm Telescope
  19. GRB 261029A : AstroSat CZTI detection
  20. GRB 261029A: SVOM/C-GFT optical observations
  21. EP261010a: Xinglong optical follow-up
  22. GRB 261029A: EP-FXT follow-up observation
  23. GRB 261029A: Fermi-LAT detection
  24. GRB 261029A: LCO optical observations (correction to GCN 46082)
  25. GRB 261029A: SVOM/COLIBRÍ (FM-GFT) optical observations
  26. GRB 261029A: LCO optical observations
  27. GRB 261029A: NOT imaging and spectroscopic redshift z = 3.27
  28. GRB261029A: Early infrared detection with MDM/MIRAGE
  29. GRB 261029A: KAIT optical observations
  30. EP261006a / AT 2026aetp: Xinglong 2.16-m optical follow-up
  31. EP261025a: EP-FXT follow-up observations
  32. GRB 261029B: Fermi GBM Final Real-time Localization
  33. GRB 261028B / MAXI J1609-487: MAXI GSC detection
  34. GRB 261029A: GOTO optical counterpart candidate
  35. GRB 261029A: SVOM detection of a burst
  36. GRB 261029A: Fermi GBM Final Real-time Localization
  37. GRB 261021A: Glowbug gamma-ray detection
  38. GRB 261028A: Fermi GBM Final Localization
  39. GRB 261026A: SVOM/ECLAIRs refined analysis
  40. GRB 261024C: GECAM-B observation
  41. GRB 261026B: AstroSat CZTI detection
  42. GRB 261024D: Insight-HXMT/HE detection
  43. GRB261026A: Infrared detection with MDM/MIRAGE
  44. GRB 261026A: SVOM/VT optical blue bump
  45. GRB 261026A: SAO RAS optical observations
  46. GRB 261024D: GECAM-B observation
  47. The EP-WXT trigger 01709321750 is likely a flaring star
  48. EP Alert 261026.29: Global MASTER-Net observations report
  49. GRB 261026A: EP-FXT follow-up observation
  50. GRB 261024A: SVOM/GRM observation
  51. GRB 261026A: Upper Limit with 60cm Panzhihua Telescope
  52. EP 261025a: J-band upper limit with MIRAGE
  53. GRB 261026A: OHP/T120 optical imaging
  54. GRB 261024D: Glowbug gamma-ray detection
  55. GRB 261026B: NuSTAR detection of prompt emission
  56. GRB 261024D: NuSTAR detection of prompt emission
  57. GRB 261024C: NuSTAR detection of prompt emission
  58. GRB 261026A: Ondrejov D50 optical limit
  59. GRB 261026A: ULL-ASTRO-MASTER optical detection with LCO 40-cm telescope at Haleakalā Observatory
  60. GRB 261026A: J-band observations by the SYSU 80cm infrared telescope
  61. GRB 261026A: SVOM/VT optical observations
  62. GRB 261026C: Fermi GBM Final Real-time Localization
  63. GRB 261020A: Insight-HXMT/HE detection
  64. SVOM GRB261026.26: Global MASTER-Net observations report
  65. GRB 261026A: WINTER J-band observations
  66. GRB 261024D: AstroSat CZTI detection of a long burst
  67. GRB 261024C: AstroSat CZTI detection of a long burst
  68. GRB 261019A: GECAM-B observation
  69. GRB 261019A: SVOM/GRM observation
  70. Fermi GRB 261026B: Global MASTER-Net observations report
  71. GRB 261026A: SVOM/VT optical observation from VHF data
  72. GRB 261026A: SVOM/COLIBRÍ (FM-GFT) optical observations
  73. GRB 261026B: Fermi GBM Final Real-time Localization
  74. GRB 261024A: NuSTAR detection of prompt emission
  75. GRB 261026A: SVOM detection of a burst
  76. GRB 261025B: Fermi GBM Final Real-time Localization
  77. EP261025a: J-band upper limit with WINTER
  78. EP261023a: J-band upper limit with WINTER
  79. EP 261025a: COLIBRÍ optical upper limit
  80. EP261025a: Einstein Probe detection of a fast X-ray transient
  81. GRB 261025A: Fermi GBM Final Localization Correction
  82. EP261023a: J band upper limit by SYSU 80cm infrared telescope
  83. GRB 261024B: Fermi GBM Final Real-time Localization
  84. EP261015a: VST optical observations
  85. GRB 261024A: BALROG localization (Fermi Trigger 814551785 / GRB 261024683)
  86. GRB 261024A: Fermi GBM Final Real-time Localization
  87. EP261023a: Mondy optical upper limit
  88. EP261015a: MAO/AZT-22 optical observations
  89. EP261015a: VLA non-detection
  90. EP261023a: Einstein Probe detection of an X-ray transient
  91. GRB 261019A: Insight-HXMT/HE detection
  92. The EP-WXT trigger 01709321472 is likely a flaring star
  93. IceCube-261020A: Upper limits from a search for additional neutrino events in IceCube
  94. NuSTAR 261020, a 830s hard X-ray transient
  95. EP261015a: GSP multiband optical follow-up observations
  96. GRB 261017A: SVOM/GRM observation
  97. GRB 261021A: Fermi GBM Final Real-time Localization
  98. EP261015a: Further optical observations with the 1.3m DFOT
  99. GRB 261020B: AstroSat CZTI detection of a short burst
  100. Fermi-LAT Gamma-ray Observations of IceCube-261020A

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