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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"

39403 results found.

  1. GRB 221120A: GIT upper limits on optical afterglow
  2. GRB 221120A: Swift detection of a likely short burst
  3. GRB 221119A: Fermi GBM detection
  4. GRB 221119A: Detection by GRBAlpha
  5. GRB 221119A: Fermi-LAT detection
  6. LAT GRB221119.63: Global MASTER-Net observations report
  7. GRB 221119A: Fermi GBM Final Real-time Localization
  8. GRB 221009A: Japanese VLBI Network observation
  9. GRB 221115B: CALET Gamma-Ray Burst Monitor detection
  10. GRB 221114A: CALET Gamma-Ray Burst Monitor detection
  11. GRB 221118A: Fermi GBM Final Real-time Localization
  12. GRB 221115B: LCOGT Optical Upper Limits
  13. Correction to GCN 32646 (GRB 221009A (Swift J1913.1+1946): MeerLICHT observations)
  14. GRB 221115B : MeerLICHT upper limits
  15. GRB 221115A: Fermi GBM detection
  16. GRB 221115B: Swift/BAT-GUANO arcminute localization
  17. GRB 221115A: Swift/BAT-GUANO detection
  18. GRB 221110A: GRANDMA observations
  19. GRB 221112A: Detection by GRBAlpha
  20. GRB 221112A: Fermi GBM Final Real-time Localization
  21. GRB 221110A: COATLI Second-Epoch Upper Limits
  22. GRB 221009A: GRANDMA/Kilonova-Catcher observations
  23. GRB 221110A: GMG upper limit
  24. GRB 221110A: Swift/UVOT Detection and Corrected UVOT Position
  25. GRB 221110A: Swift-BAT refined analysis
  26. GRB 221110A: Swift-XRT refined Analysis
  27. GRB 221110A: Enhanced Swift-XRT position
  28. GRB 221110A: VLT/X-shooter redshift
  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 221107A: Detection by GRBAlpha
  39. GRB 221009A: Extended Bad Time Intervals for Fermi LAT data
  40. GRB 221107A: Swift/BAT-GUANO detection outside the coded FOV
  41. GRB 221107A: Fermi GBM Final Localization
  42. Correction to GCN 32852 (GRB 221009A: SARA-RM 1m Optical Afterglow Detection)
  43. IceCube Alert 221104.26: Global MASTER-Net observations report
  44. Fermi-LAT gamma-ray observations of IceCube-221104A
  45. GRB 221029A: CALET Gamma-Ray Burst Monitor detection
  46. High-precision position of the compact radio counterpart to GRB221009A
  47. GRB 221028A: GRANDMA observations
  48. GRB 221027B: GRANDMA observations
  49. GRB 221028A: Detection by VZLUSAT-2
  50. GRB 221029A: Fermi GBM observation
  51. GRB 221027C: AstroSat CZTI detection
  52. Konus-Wind detection of GRB 221022C
  53. GRB 221029A: Fermi GBM Final Localization
  54. GRB 221028A: Swift-XRT refined Analysis
  55. GRB 221028A: 1.3m DFOT Optical upper limit
  56. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  57. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  58. GRB 221028A: Correction to GCN 32893 - Fluence and flux are for 50-150 keV
  59. GRB 221028A: AKO Optical Upper Limit
  60. GRB 221028A, Swift-BAT refined analysis
  61. GRB 221027B: Swift-BAT refined analysis
  62. GRB 221029A: Swift/BAT-GUANO detection outside the coded FOV
  63. GRB 221029A: Detection by GRBAlpha
  64. GRB 221028A: CrAO/ZTSh optical upper limit
  65. GRB 221028A: COATLI Upper Limits
  66. GRB 221028A: HCT optical upper limit
  67. GRB 221028A: AGILE detection
  68. GRB 221027A: AGILE detection
  69. GRB 221028A: MITSuME Okayama optical upper limits
  70. GRB 221028B: MAXI/GSC detection
  71. GRB 221028A: LCOGT Optical Upper Limits
  72. GRB 221027B: COATLI Upper Limits
  73. Swift GRB 221028A: Global MASTER-Net observations report
  74. GRB 221028A: BOOTES-4/MET optical upper limit
  75. LIGO-Virgo-KAGRA and GEO600 statement on GRB 221009A
  76. GRB 221028A: GIT optical upper limit
  77. GRB 221027B: Swift/UVOT Upper Limits
  78. GRB 221028A: Swift detection of a burst
  79. GRB 221027B: FRAM-ORM and Ondrejov SBT optical limits
  80. Konus-Wind detection of GRB 221017A
  81. Swift GRB 221027B: Global MASTER-Net observations report
  82. GRB 221027B: Swift-XRT refined Analysis
  83. GRB 221027B: BOOTES-1 optical upper limit
  84. GRB 221027B: Enhanced Swift-XRT position
  85. GRB 221027B: Swift detection of a burst
  86. GRB 221027A: Fermi GBM detection
  87. IPN triangulation of GRB 221025A (short)
  88. Konus-Wind detection of GRB 221022B
  89. GRB 221024A: Mondy optical observations
  90. GRB 221027A: Fermi-LAT detection
  91. GRB 221027A: Fermi GBM Final Real-time Localization
  92. GRB 221009A: Further Gemini-South Infrared Observations
  93. GRB 221024A: GRANDMA observations
  94. Fermi Gamma-ray Burst Monitor trigger 688431261/221025954 is not a GRB
  95. IPN triangulation of GRB 221022C (short)
  96. GRB 221023A: AGILE/GRID analysis
  97. GRB 221024A: Swift-BAT refined analysis
  98. GRB 221025A: AstroSat CZTI detection
  99. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  100. GRB 221025A: Fermi GBM Observation

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