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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"

36398 results found.

  1. Optical polarization observation of GRB 221009A
  2. GRB 221126A: Fermi GBM observation
  3. GRB 221126A: AGILE detection
  4. GRB 221127A: Detection by GRBAlpha
  5. GRB 221126A: AstroSat CZTI detection
  6. GRB 221126A: Swift/BAT-GUANO detection outside the coded FOV
  7. IPN triangulation of GRB 221124A (long)
  8. GRB 221126A: Fermi GBM Final Real-time Localization
  9. GRB 221124A: Swift/BAT-GUANO detection
  10. GRB 221120A: Detection by VZLUSAT-2
  11. GRB 221124A: CALET Gamma-Ray Burst Monitor detection
  12. GRB 221120A: TURBO Optical Upper Limit
  13. GRB 221122A: Detection by GRBAlpha
  14. GRB 221120A: VIRT Optical Upper Limit
  15. GRB 221121A: CALET Gamma-Ray Burst Monitor detection
  16. GRB 221009A：DAMPE observed a 34.7 GeV photon at 1.36 hour after the GBM trigger
  17. GRB 221120A: GTC Confirmation of an Underlying Galaxy
  18. IPN triangulation of GRB 221121A (long)
  19. GRB 221120A: Swift-BAT refined analysis
  20. GRB221121A: AstroSat CZTI detection
  21. GRB 221120A: AKO Telescope Upper Limits
  22. GRB221120A: WIRC near-IR imaging of the afterglow candidate
  23. GRB 221120A: Liverpool Telescope Upper Limits
  24. GRB 221120A: Archival PS1 Imaging of Faint Source near XRT position
  25. GRB 221120A: Fermi GBM observation
  26. GRB 221120A: Swift-XRT refined Analysis
  27. GRB 221120A: Enhanced Swift-XRT position
  28. GRB 221121A: Fermi GBM Final Real-time Localization
  29. GRB 221120A is a short burst
  30. GRB 221120A: Swift/UVOT Upper Limits
  31. GRB 221120A: LDT Optical Afterglow Candidate
  32. GRB 221120A: GIT upper limits on optical afterglow
  33. GRB 221120A: Swift detection of a likely short burst
  34. GRB 221119A: Fermi GBM detection
  35. GRB 221119A: Detection by GRBAlpha
  36. GRB 221119A: Fermi-LAT detection
  37. GRB 221119A: Fermi GBM Final Real-time Localization
  38. GRB 221009A: Japanese VLBI Network observation
  39. GRB 221115B: CALET Gamma-Ray Burst Monitor detection
  40. GRB 221114A: CALET Gamma-Ray Burst Monitor detection
  41. GRB 221118A: Fermi GBM Final Real-time Localization
  42. GRB 221115B: LCOGT Optical Upper Limits
  43. Correction to GCN 32646 (GRB 221009A (Swift J1913.1+1946): MeerLICHT observations)
  44. GRB 221115B : MeerLICHT upper limits
  45. GRB 221115A: Fermi GBM detection
  46. GRB 221115B: Swift/BAT-GUANO arcminute localization
  47. GRB 221115A: Swift/BAT-GUANO detection
  48. GRB 221110A: GRANDMA observations
  49. GRB 221112A: Detection by GRBAlpha
  50. GRB 221112A: Fermi GBM Final Real-time Localization
  51. GRB 221110A: COATLI Second-Epoch Upper Limits
  52. GRB 221009A: GRANDMA/Kilonova-Catcher observations
  53. GRB 221110A: GMG upper limit
  54. GRB 221110A: Swift/UVOT Detection and Corrected UVOT Position
  55. GRB 221110A: Swift-BAT refined analysis
  56. GRB 221110A: Swift-XRT refined Analysis
  57. GRB 221110A: Enhanced Swift-XRT position
  58. GRB 221110A: VLT/X-shooter redshift
  59. GRB 221110A: COATLI Afterglow detection
  60. GRB 221110A: LCOGT Optical Afterglow Detection
  61. GRB 221110A: Swift detection of a burst with an optical counterpart
  62. GRB 221009A: Hubble Space Telescope observations
  63. GRB 221104A: Fermi GBM Final Localization
  64. GRB 221108A: Fermi GBM Final Localization
  65. GRB 221107A: Fermi GBM Observation
  66. GRB 221107A: Detection by GRBAlpha
  67. GRB 221009A: Extended Bad Time Intervals for Fermi LAT data
  68. GRB 221107A: Swift/BAT-GUANO detection outside the coded FOV
  69. GRB 221107A: Fermi GBM Final Localization
  70. Correction to GCN 32852 (GRB 221009A: SARA-RM 1m Optical Afterglow Detection)
  71. GRB 221029A: CALET Gamma-Ray Burst Monitor detection
  72. High-precision position of the compact radio counterpart to GRB221009A
  73. GRB 221028A: GRANDMA observations
  74. GRB 221027B: GRANDMA observations
  75. GRB 221028A: Detection by VZLUSAT-2
  76. GRB 221029A: Fermi GBM observation
  77. GRB 221027C: AstroSat CZTI detection
  78. Konus-Wind detection of GRB 221022C
  79. GRB 221029A: Fermi GBM Final Localization
  80. GRB 221028A: Swift-XRT refined Analysis
  81. GRB 221028A: 1.3m DFOT Optical upper limit
  82. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  83. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  84. GRB 221028A: Correction to GCN 32893 - Fluence and flux are for 50-150 keV
  85. GRB 221028A: AKO Optical Upper Limit
  86. GRB 221028A, Swift-BAT refined analysis
  87. GRB 221027B: Swift-BAT refined analysis
  88. GRB 221029A: Swift/BAT-GUANO detection outside the coded FOV
  89. GRB 221029A: Detection by GRBAlpha
  90. GRB 221028A: CrAO/ZTSh optical upper limit
  91. GRB 221028A: COATLI Upper Limits
  92. GRB 221028A: HCT optical upper limit
  93. GRB 221028A: AGILE detection
  94. GRB 221027A: AGILE detection
  95. GRB 221028A: MITSuME Okayama optical upper limits
  96. GRB 221028B: MAXI/GSC detection
  97. GRB 221028A: LCOGT Optical Upper Limits
  98. GRB 221027B: COATLI Upper Limits
  99. Swift GRB 221028A: Global MASTER-Net observations report
  100. GRB 221028A: BOOTES-4/MET optical upper limit

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