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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"

27333 results found.

  1. GRB 221120A: Fermi GBM observation
  2. GRB 221120A: Swift-XRT refined Analysis
  3. GRB221120A: Montarrenti Observatory Upper Limit
  4. GRB 221121A: Fermi GBM Final Real-time Localization
  5. GRB 221120A: Swift/UVOT Upper Limits
  6. GRB 221120A: GIT upper limits on optical afterglow
  7. GRB 221120A: Swift detection of a likely short burst
  8. GRB 221119A: Fermi GBM detection
  9. GRB 221119A: Fermi-LAT detection
  10. LAT GRB221119.63: Global MASTER-Net observations report
  11. GRB 221119A: Fermi GBM Final Real-time Localization
  12. GRB 221009A: Japanese VLBI Network observation
  13. GRB 221115B: CALET Gamma-Ray Burst Monitor detection
  14. GRB 221114A: CALET Gamma-Ray Burst Monitor detection
  15. GRB 221118A: Fermi GBM Final Real-time Localization
  16. GRB 221115B: LCOGT Optical Upper Limits
  17. GRB 221115B : MeerLICHT upper limits
  18. GRB 221115A: Fermi GBM detection
  19. GRB 221115B: Swift/BAT-GUANO arcminute localization
  20. GRB 221115A: Swift/BAT-GUANO detection
  21. GRB 221110A: GRANDMA observations
  22. GRB 221112A: Fermi GBM Final Real-time Localization
  23. GRB 221110A: COATLI Second-Epoch Upper Limits
  24. GRB 221009A: GRANDMA/Kilonova-Catcher observations
  25. GRB 221110A: GMG upper limit
  26. GRB 221110A: Swift/UVOT Detection and Corrected UVOT Position
  27. GRB 221110A: Swift-BAT refined analysis
  28. GRB 221110A: Swift-XRT refined Analysis
  29. GRB 221110A: COATLI Afterglow detection
  30. GRB 221110A: LCOGT Optical Afterglow Detection
  31. GRB 221110A: Swift detection of a burst with an optical counterpart
  32. Swift GRB221110.10: Global MASTER-Net OT detection
  33. Swift GRB221110.10: Global MASTER-Net observations report
  34. GRB 221009A: Hubble Space Telescope observations
  35. GRB 221104A: Fermi GBM Final Localization
  36. GRB 221108A: Fermi GBM Final Localization
  37. GRB 221107A: Fermi GBM Observation
  38. GRB 221009A: Extended Bad Time Intervals for Fermi LAT data
  39. GRB 221107A: Swift/BAT-GUANO detection outside the coded FOV
  40. GRB 221107A: Fermi GBM Final Localization
  41. Correction to GCN 32852 (GRB 221009A: SARA-RM 1m Optical Afterglow Detection)
  42. IceCube Alert 221104.26: Global MASTER-Net observations report
  43. GRB 221029A: CALET Gamma-Ray Burst Monitor detection
  44. GRB 221028A: GRANDMA observations
  45. GRB 221027B: GRANDMA observations
  46. GRB 221029A: Fermi GBM observation
  47. Konus-Wind detection of GRB 221022C
  48. GRB 221029A: Fermi GBM Final Localization
  49. GRB 221028A: Swift-XRT refined Analysis
  50. GRB 221028A: 1.3m DFOT Optical upper limit
  51. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  52. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  53. GRB 221028A, Swift-BAT refined analysis
  54. GRB 221027B: Swift-BAT refined analysis
  55. GRB 221029A: Swift/BAT-GUANO detection outside the coded FOV
  56. GRB 221029A: Detection by GRBAlpha
  57. GRB 221028A: COATLI Upper Limits
  58. Trigger 1132968: Swift trigger is the Crab
  59. GRB 221028A: MITSuME Okayama optical upper limits
  60. GRB 221028A: LCOGT Optical Upper Limits
  61. GRB 221027B: COATLI Upper Limits
  62. Swift GRB 221028A: Global MASTER-Net observations report
  63. GRB 221028A: BOOTES-4/MET optical upper limit
  64. GRB 221027B: Swift/UVOT Upper Limits
  65. GRB 221028A: Swift detection of a burst
  66. GRB 221027B: FRAM-ORM and Ondrejov SBT optical limits
  67. Swift GRB 221027B: Global MASTER-Net observations report
  68. GRB 221027B: Swift-XRT refined Analysis
  69. GRB 221027B: BOOTES-1 optical upper limit
  70. GRB 221027B: Swift detection of a burst
  71. GRB 221027A: Fermi GBM detection
  72. IPN triangulation of GRB 221025A (short)
  73. GRB 221027A: Fermi-LAT detection
  74. GRB 221027A: Fermi GBM Final Real-time Localization
  75. GRB 221024A: GRANDMA observations
  76. Fermi Gamma-ray Burst Monitor trigger 688431261/221025954 is not a GRB
  77. IPN triangulation of GRB 221022C (short)
  78. GRB 221024A: Swift-BAT refined analysis
  79. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  80. GRB 221025A: Fermi GBM Observation
  81. GRB 221009A: spectroscopic confirmation of SN in LBT spectra
  82. GRB 221024A: Swift/UVOT UV upper limits
  83. GRB 221024A: Swift-XRT refined Analysis
  84. GRB 221023A: Fermi GBM Observation
  85. GRB 221022B: Detection by GRBAlpha
  86. GRB 221025A: Fermi-LAT detection
  87. LAT GRB221025.04: Global MASTER-Net observations report
  88. GRB 221022A: Fermi GBM detection
  89. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  90. GRB 221023A: Fermi-LAT detection
  91. GRB 221022B: Fermi GBM detection
  92. GRB 221021A: Fermi GBM observation
  93. GRB 221009A: Determination of the black holes mass and spin
  94. GRB 221024A: Swift detection of a burst
  95. GRB 221023A: Fermi GBM Final Localization
  96. GRB 221022A: Swift/BAT-GUANO detection
  97. GRB 221022B: Swift/BAT-GUANO detection outside the coded FOV
  98. GRB 221022B: AGILE detection
  99. GRB 221009A: James Webb Space Telescope Observations
  100. GRB 221022B: Fermi GBM Final Real-time Localization

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