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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').
Advanced Search

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.

Advanced Search Examples (click to copy):

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

28259 results found.

  1. GRB 221126A: AstroSat CZTI detection
  2. GRB 221126A: Swift/BAT-GUANO detection outside the coded FOV
  3. IPN triangulation of GRB 221124A (long)
  4. GRB 221126A: Fermi GBM Final Real-time Localization
  5. GRB 221124A: Swift/BAT-GUANO detection
  6. GRB 221120A: Detection by VZLUSAT-2
  7. GRB 221124A: CALET Gamma-Ray Burst Monitor detection
  8. IceCube-221124A - IceCube observation of a high-energy neutrino candidate track-like event
  9. GRB 221120A: TURBO Optical Upper Limit
  10. GRB 221122A: Detection by GRBAlpha
  11. GRB 221120A: VIRT Optical Upper Limit
  12. GRB 221121A: CALET Gamma-Ray Burst Monitor detection
  13. GRB 221009A：DAMPE observed a 34.7 GeV photon at 1.36 hour after the GBM trigger
  14. IPN triangulation of GRB 221121A (long)
  15. GRB221121A: AstroSat CZTI detection
  16. GRB 221120A: AKO Telescope Upper Limits
  17. GRB221120A: WIRC near-IR imaging of the afterglow candidate
  18. GRB 221120A: Liverpool Telescope Upper Limits
  19. GRB 221120A: Archival PS1 Imaging of Faint Source near XRT position
  20. GRB 221120A: Swift-XRT refined Analysis
  21. GRB 221120A: Enhanced Swift-XRT position
  22. GRB 221121A: Fermi GBM Final Real-time Localization
  23. GRB 221120A: Swift/UVOT Upper Limits
  24. GRB 221120A: LDT Optical Afterglow Candidate
  25. GRB 221120A: GIT upper limits on optical afterglow
  26. GRB 221120A: Swift detection of a likely short burst
  27. GRB 221119A: Fermi GBM detection
  28. GRB 221119A: Detection by GRBAlpha
  29. GRB 221119A: Fermi-LAT detection
  30. GRB 221119A: Fermi GBM Final Real-time Localization
  31. GRB 221115B: CALET Gamma-Ray Burst Monitor detection
  32. GRB 221114A: CALET Gamma-Ray Burst Monitor detection
  33. GRB 221118A: Fermi GBM Final Real-time Localization
  34. Correction to GCN 32646 (GRB 221009A (Swift J1913.1+1946): MeerLICHT observations)
  35. GRB 221115B : MeerLICHT upper limits
  36. GRB 221115A: Fermi GBM detection
  37. GRB 221115B: Swift/BAT-GUANO arcminute localization
  38. GRB 221115A: Swift/BAT-GUANO detection
  39. GRB 221110A: GRANDMA observations
  40. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 November 9
  41. GRB 221112A: Detection by GRBAlpha
  42. GRB 221112A: Fermi GBM Final Real-time Localization
  43. GRB 221009A: GRANDMA/Kilonova-Catcher observations
  44. GRB 221110A: Swift/UVOT Detection and Corrected UVOT Position
  45. GRB 221110A: Swift-XRT refined Analysis
  46. GRB 221110A: Enhanced Swift-XRT position
  47. GRB 221110A: VLT/X-shooter redshift
  48. GRB 221110A: COATLI Afterglow detection
  49. GRB 221110A: LCOGT Optical Afterglow Detection
  50. GRB 221110A: Swift detection of a burst with an optical counterpart
  51. Swift GRB221110.10: Global MASTER-Net OT detection
  52. GRB 221009A: Hubble Space Telescope observations
  53. GRB 221104A: Fermi GBM Final Localization
  54. GRB 221108A: Fermi GBM Final Localization
  55. GRB 221107A: Detection by GRBAlpha
  56. GRB 221107A: Swift/BAT-GUANO detection outside the coded FOV
  57. GRB 221107A: Fermi GBM Final Localization
  58. Correction to GCN 32852 (GRB 221009A: SARA-RM 1m Optical Afterglow Detection)
  59. IceCube-221104A - IceCube observation of a high-energy neutrino candidate track-like event
  60. GRB 221029A: CALET Gamma-Ray Burst Monitor detection
  61. GRB 221028A: GRANDMA observations
  62. GRB 221027B: GRANDMA observations
  63. GRB 221028A: Detection by VZLUSAT-2
  64. GRB 221027C: AstroSat CZTI detection
  65. Konus-Wind detection of GRB 221022C
  66. GRB 221029A: Fermi GBM Final Localization
  67. GRB 221028A: Swift-XRT refined Analysis
  68. GRB 221028A: 1.3m DFOT Optical upper limit
  69. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  70. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  71. GRB 221028A: AKO Optical Upper Limit
  72. GRB 221029A: Swift/BAT-GUANO detection outside the coded FOV
  73. GRB 221029A: Detection by GRBAlpha
  74. GRB 221028A: CrAO/ZTSh optical upper limit
  75. GRB 221028A: COATLI Upper Limits
  76. Trigger 1132968: Swift trigger is the Crab
  77. GRB 221028A: HCT optical upper limit
  78. GRB 221028A: AGILE detection
  79. GRB 221027A: AGILE detection
  80. GRB 221028A: MITSuME Okayama optical upper limits
  81. GRB 221028B: MAXI/GSC detection
  82. GRB 221028A: LCOGT Optical Upper Limits
  83. GRB 221027B: COATLI Upper Limits
  84. GRB 221028A: BOOTES-4/MET optical upper limit
  85. GRB 221028A: GIT optical upper limit
  86. GRB 221027B: Swift/UVOT Upper Limits
  87. GRB 221028A: Swift detection of a burst
  88. Konus-Wind detection of GRB 221017A
  89. GRB 221027B: Swift-XRT refined Analysis
  90. GRB 221027B: BOOTES-1 optical upper limit
  91. GRB 221027B: Enhanced Swift-XRT position
  92. GRB 221027B: Swift detection of a burst
  93. GRB 221027A: Fermi GBM detection
  94. IPN triangulation of GRB 221025A (short)
  95. Konus-Wind detection of GRB 221022B
  96. GRB 221024A: Mondy optical observations
  97. GRB 221027A: Fermi-LAT detection
  98. GRB 221027A: Fermi GBM Final Real-time Localization
  99. GRB 221009A: Further Gemini-South Infrared Observations
  100. GRB 221024A: GRANDMA observations

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