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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"

36403 results found.

  1. Swift GRB 221201A: Global MASTER-Net observations report
  2. Konus-Wind detection of GRB 221124A
  3. GRB 221201A: Swift detection of a burst
  4. GRB 221201A: Fermi GBM Final Real-time Localization
  5. Fermi Gamma-ray Burst Monitor trigger 691534074/221130867 is not a GRB
  6. Optical polarization observation of GRB 221009A
  7. GRB 221126A: Fermi GBM observation
  8. GRB 221126A: AGILE detection
  9. GRB 221127A: Detection by GRBAlpha
  10. GRB 221126A: AstroSat CZTI detection
  11. GRB 221126A: Swift/BAT-GUANO detection outside the coded FOV
  12. IPN triangulation of GRB 221124A (long)
  13. GRB 221126A: Fermi GBM Final Real-time Localization
  14. GRB 221124A: Swift/BAT-GUANO detection
  15. GRB 221120A: Detection by VZLUSAT-2
  16. GRB 221124A: CALET Gamma-Ray Burst Monitor detection
  17. GRB 221120A: TURBO Optical Upper Limit
  18. GRB 221122A: Detection by GRBAlpha
  19. GRB 221120A: VIRT Optical Upper Limit
  20. GRB 221121A: CALET Gamma-Ray Burst Monitor detection
  21. GRB 221009A：DAMPE observed a 34.7 GeV photon at 1.36 hour after the GBM trigger
  22. GRB 221120A: GTC Confirmation of an Underlying Galaxy
  23. IPN triangulation of GRB 221121A (long)
  24. GRB 221120A: Swift-BAT refined analysis
  25. GRB221121A: AstroSat CZTI detection
  26. GRB 221120A: AKO Telescope Upper Limits
  27. GRB221120A: WIRC near-IR imaging of the afterglow candidate
  28. GRB 221120A: Liverpool Telescope Upper Limits
  29. GRB 221120A: Archival PS1 Imaging of Faint Source near XRT position
  30. GRB 221120A: Fermi GBM observation
  31. GRB 221120A: Swift-XRT refined Analysis
  32. GRB 221120A: Enhanced Swift-XRT position
  33. GRB 221121A: Fermi GBM Final Real-time Localization
  34. GRB 221120A is a short burst
  35. GRB 221120A: Swift/UVOT Upper Limits
  36. GRB 221120A: LDT Optical Afterglow Candidate
  37. GRB 221120A: GIT upper limits on optical afterglow
  38. GRB 221120A: Swift detection of a likely short burst
  39. GRB 221119A: Fermi GBM detection
  40. GRB 221119A: Detection by GRBAlpha
  41. GRB 221119A: Fermi-LAT detection
  42. GRB 221119A: Fermi GBM Final Real-time Localization
  43. GRB 221009A: Japanese VLBI Network observation
  44. GRB 221115B: CALET Gamma-Ray Burst Monitor detection
  45. GRB 221114A: CALET Gamma-Ray Burst Monitor detection
  46. GRB 221118A: Fermi GBM Final Real-time Localization
  47. GRB 221115B: LCOGT Optical Upper Limits
  48. Correction to GCN 32646 (GRB 221009A (Swift J1913.1+1946): MeerLICHT observations)
  49. GRB 221115B : MeerLICHT upper limits
  50. GRB 221115A: Fermi GBM detection
  51. GRB 221115B: Swift/BAT-GUANO arcminute localization
  52. GRB 221115A: Swift/BAT-GUANO detection
  53. GRB 221110A: GRANDMA observations
  54. GRB 221112A: Detection by GRBAlpha
  55. GRB 221112A: Fermi GBM Final Real-time Localization
  56. GRB 221110A: COATLI Second-Epoch Upper Limits
  57. GRB 221009A: GRANDMA/Kilonova-Catcher observations
  58. GRB 221110A: GMG upper limit
  59. GRB 221110A: Swift/UVOT Detection and Corrected UVOT Position
  60. GRB 221110A: Swift-BAT refined analysis
  61. GRB 221110A: Swift-XRT refined Analysis
  62. GRB 221110A: Enhanced Swift-XRT position
  63. GRB 221110A: VLT/X-shooter redshift
  64. GRB 221110A: COATLI Afterglow detection
  65. GRB 221110A: LCOGT Optical Afterglow Detection
  66. GRB 221110A: Swift detection of a burst with an optical counterpart
  67. GRB 221009A: Hubble Space Telescope observations
  68. GRB 221104A: Fermi GBM Final Localization
  69. GRB 221108A: Fermi GBM Final Localization
  70. GRB 221107A: Fermi GBM Observation
  71. GRB 221107A: Detection by GRBAlpha
  72. GRB 221009A: Extended Bad Time Intervals for Fermi LAT data
  73. GRB 221107A: Swift/BAT-GUANO detection outside the coded FOV
  74. GRB 221107A: Fermi GBM Final Localization
  75. Correction to GCN 32852 (GRB 221009A: SARA-RM 1m Optical Afterglow Detection)
  76. GRB 221029A: CALET Gamma-Ray Burst Monitor detection
  77. High-precision position of the compact radio counterpart to GRB221009A
  78. GRB 221028A: GRANDMA observations
  79. GRB 221027B: GRANDMA observations
  80. GRB 221028A: Detection by VZLUSAT-2
  81. GRB 221029A: Fermi GBM observation
  82. GRB 221027C: AstroSat CZTI detection
  83. Konus-Wind detection of GRB 221022C
  84. GRB 221029A: Fermi GBM Final Localization
  85. GRB 221028A: Swift-XRT refined Analysis
  86. GRB 221028A: 1.3m DFOT Optical upper limit
  87. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  88. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  89. GRB 221028A: Correction to GCN 32893 - Fluence and flux are for 50-150 keV
  90. GRB 221028A: AKO Optical Upper Limit
  91. GRB 221028A, Swift-BAT refined analysis
  92. GRB 221027B: Swift-BAT refined analysis
  93. GRB 221029A: Swift/BAT-GUANO detection outside the coded FOV
  94. GRB 221029A: Detection by GRBAlpha
  95. GRB 221028A: CrAO/ZTSh optical upper limit
  96. GRB 221028A: COATLI Upper Limits
  97. GRB 221028A: HCT optical upper limit
  98. GRB 221028A: AGILE detection
  99. GRB 221027A: AGILE detection
  100. GRB 221028A: MITSuME Okayama optical upper limits

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