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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"

45747 results found.

  1. GRB 261029A: LCO optical observations (correction to GCN 46082)
  2. GRB 261029A: SVOM/COLIBRÍ (FM-GFT) optical observations
  3. GRB 261011A: LCO optical observations
  4. GRB 261029A: NOT imaging and spectroscopic redshift z = 3.27
  5. GRB261029A: Early infrared detection with MDM/MIRAGE
  6. GRB 261029A: KAIT optical observations
  7. GRB 261029A: TRT optical observations
  8. EP261006a / AT 2026aetp: Xinglong 2.16-m optical follow-up
  9. EP261025a: EP-FXT follow-up observations
  10. GRB 261029B: Fermi GBM Final Real-time Localization
  11. GRB 261028B / MAXI J1609-487: MAXI GSC detection
  12. GRB 261029A: GOTO optical counterpart candidate
  13. GRB 261029A: SVOM detection of a burst
  14. GRB 261029A: Fermi GBM Final Real-time Localization
  15. GRB 261021A: Glowbug gamma-ray detection
  16. GRB 261028A: Fermi GBM Final Localization
  17. GRB 261026A: SVOM/ECLAIRs refined analysis
  18. GRB 261024C: GECAM-B observation
  19. GRB 261026B: AstroSat CZTI detection
  20. GRB 261024D: Insight-HXMT/HE detection
  21. GRB261026A: Infrared detection with MDM/MIRAGE
  22. GRB 261026A: SVOM/VT optical blue bump
  23. GRB 261026A: SAO RAS optical observations
  24. GRB 261024D: GECAM-B observation
  25. The EP-WXT trigger 01709321750 is likely a flaring star
  26. EP Alert 261026.29: Global MASTER-Net observations report
  27. GRB 261026A: EP-FXT follow-up observation
  28. GRB 261024A: SVOM/GRM observation
  29. GRB 261026A: Upper Limit with 60cm Panzhihua Telescope
  30. EP 261025a: J-band upper limit with MIRAGE
  31. GRB 261026A: OHP/T120 optical imaging
  32. GRB 261024D: Glowbug gamma-ray detection
  33. GRB 261026B: NuSTAR detection of prompt emission
  34. GRB 261024D: NuSTAR detection of prompt emission
  35. GRB 261024C: NuSTAR detection of prompt emission
  36. GRB 261026A: Ondrejov D50 optical limit
  37. GRB 261026A: ULL-ASTRO-MASTER optical detection with LCO 40-cm telescope at Haleakalā Observatory
  38. GRB 261026A: J-band observations by the SYSU 80cm infrared telescope
  39. GRB 261026A: SVOM/VT optical observations
  40. IPN triangulation of GRB 260730B
  41. GRB 261026C: Fermi GBM Final Real-time Localization
  42. GRB 261020A: Insight-HXMT/HE detection
  43. SVOM GRB261026.26: Global MASTER-Net observations report
  44. GRB 261026A: WINTER J-band observations
  45. GRB 261024D: AstroSat CZTI detection of a long burst
  46. GRB 261024C: AstroSat CZTI detection of a long burst
  47. GRB 261019A: GECAM-B observation
  48. GRB 261019A: SVOM/GRM observation
  49. Fermi GRB 261026B: Global MASTER-Net observations report
  50. GRB 261026A: SVOM/VT optical observation from VHF data
  51. GRB 261026A: KAIT optical observations
  52. GRB 261026A: SVOM/COLIBRÍ (FM-GFT) optical observations
  53. GRB 261026B: Fermi GBM Final Real-time Localization
  54. GRB 261024A: NuSTAR detection of prompt emission
  55. GRB 261026A: SVOM detection of a burst
  56. GRB 261025B: Fermi GBM Final Real-time Localization
  57. EP261025a: J-band upper limit with WINTER
  58. EP261023a: J-band upper limit with WINTER
  59. EP 261025a: COLIBRÍ optical upper limit
  60. EP261025a: Einstein Probe detection of a fast X-ray transient
  61. GRB 261025A: Fermi GBM Final Localization Correction
  62. EP261023a: J band upper limit by SYSU 80cm infrared telescope
  63. GRB 261024B: Fermi GBM Final Real-time Localization
  64. EP261015a: VST optical observations
  65. GRB 261024A: BALROG localization (Fermi Trigger 814551785 / GRB 261024683)
  66. GRB 261024A: Fermi GBM Final Real-time Localization
  67. EP261023a: Mondy optical upper limit
  68. EP261015a: MAO/AZT-22 optical observations
  69. EP261015a: VLA non-detection
  70. EP261023a: NOT optical counterpart candidate
  71. EP261023a: Einstein Probe detection of an X-ray transient
  72. GRB 261019A: Insight-HXMT/HE detection
  73. The EP-WXT trigger 01709321472 is likely a flaring star
  74. IceCube-261020A: Upper limits from a search for additional neutrino events in IceCube
  75. NuSTAR 261020, a 830s hard X-ray transient
  76. EP261015a: GSP multiband optical follow-up observations
  77. GRB 261017A: SVOM/GRM observation
  78. GRB 261021A: Fermi GBM Final Real-time Localization
  79. EP261015a: Further optical observations with the 1.3m DFOT
  80. GRB 261020B: AstroSat CZTI detection of a short burst
  81. Fermi-LAT Gamma-ray Observations of IceCube-261020A
  82. EP261015a: AZT-20 Assy-Turgen optical observations
  83. GRB 261020A: Fermi GBM Observation
  84. GRB 261017A: SAO RAS optical upper limit
  85. EP261015a: Wendelstein 43 cm optical observations
  86. GRB 260903A
  87. EP261015a: Follow-up with the 1.3m DFOT
  88. EP261015a: Terskol Zeiss-2000 optical upper limit
  89. EP261007b: Further EP-FXT follow-up observations
  90. GRB 261017A: COLIBRÍ optical upper limit
  91. IceCube-261020A - IceCube observation of a high-energy neutrino candidate track-like event
  92. GRB 261020A: MAXI GSC detection
  93. GRB 261020A: Fermi GBM Final Real-time Localization
  94. EP261015a: COLIBRÍ optical observations of a rebrightening
  95. Konus-Wind detection of GRB 261017A
  96. GRB 261019A: Fermi GBM Final Localization
  97. GRB 261017A: Possible Swift/UVOT Detection
  98. GRB 261017A: Luminance-band upper limit from a 28cm telescope in Chengde
  99. GRB 261017A: R-band upper limit with the 1.3-m DFOT
  100. GRB 261017A: Swift-BAT refined analysis

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