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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"

21470 results found.

  1. GRB 220514B: Tiled Swift observations
  2. GRB 220427A: MeerLICHT afterglow observations
  3. GRB 220511A: Fermi GBM observation
  4. GRB 220511A: Swift-XRT observations
  5. GRB 220511A: AstroSat CZTI detection
  6. GRB 220511A: BOOTES-2/TELMA optical upper limit
  7. GRB 220511A: Swift ToO observations
  8. GRB 220511A: Swift/BAT-GUANO arcminute localization
  9. GRB 220506A: MITSuME Akeno optical upper limits
  10. GRB 220506A: GIT optical upper limit.
  11. GRB 220506A: BOOTES-5/JGT optical upper limit
  12. GRB 220506A: Swift-XRT afterglow detection
  13. GRB 220506A: Tiled Swift observations
  14. Swift-BAT triggers 1105560-1 are not GRBs
  15. Swift GRB220506.51: Global MASTER-Net observations report
  16. GRB 220430A: Nanshan/NEXT optical upper limit
  17. GRB 220430A: Nanshan/HMT optical upper limit
  18. GRB 220430A: GIT optical upper limits
  19. IPN triangulation of GRB 220423A
  20. GRB 220427A: LCO Optical Observations
  21. GRB 220501A: Swift-BAT refined analysis
  22. GRB 220427A: GRANDMA Early Optical Afterglow Detection
  23. GRB 220501A: BOOTES-1 optical upper limit
  24. GRB 220501A: Fermi GBM observation
  25. GRB 220430A: AstroSat CZTI detection
  26. GRB 220501A: Swift detection of a burst
  27. GRB 220430A: Swift-BAT refined analysis
  28. GRB 220430A: CAHA 2.2m telescope optical limit
  29. GRB 220430A: Swift-XRT refined Analysis
  30. Swift GRB 220430A: Global MASTER-Net observations report
  31. GRB 220430A: GRANDMA observations
  32. GRB 220430A: Mondy and AbAO optical upper limits
  33. GRB 220430A: AGILE detection
  34. GRB 220430A: MeerLICHT optical upper limits
  35. GRB 220430A: Enhanced Swift-XRT position
  36. GRB 220430A: Swift detection of a burst or Swift J0630.4+0932
  37. GRB 220427A: Swift-BAT refined analysis
  38. GRB 220426A: Swift-XRT and UVOT observations
  39. GRB 220423A: Detection by VZLUSAT-2
  40. Konus-Wind detection of GRB 220427A
  41. GRB 220427A: Swift-XRT refined Analysis
  42. GRB 220427A: Enhanced Swift-XRT position
  43. GRB 220426A: Tiled Swift observations
  44. GRB 220427A: Swift detection of a burst with an optical counterpart
  45. Konus-Wind detection of GRB 220426A
  46. IPN triangulation of GRB 220426A
  47. GRB 220426C: Swift/BAT-GUANO detection outside the coded FOV (short)
  48. GRB 220426A: Swift/BAT-GUANO detection outside the coded FOV
  49. GRB 220423A: Swift/BAT-GUANO detection outside the coded FOV
  50. GRB 220421A: Fermi GBM observation
  51. GRB 220421A: Swift/BAT-GUANO detection outside the coded FOV
  52. GRB 220418B: Swift-XRT observations
  53. GRB 220418B Fermi GBM observation
  54. GRB 220420A: Swift/BAT-GUANO detection outside the coded FOV
  55. GRB 220403C: Further Swift-XRT observations
  56. GRB 220418B: Swift ToO observations
  57. GRB 220417A: Fermi GBM detection
  58. GRB 220418B: Swift/BAT-GUANO refined location of a short burst
  59. GRB 220418B: Swift/BAT-GUANO candidate arcminute localization of a short burst
  60. GRB 220417A: Swift/BAT-GUANO detection outside the coded FOV
  61. GRB 220412B: Swift/UVOT Upper Limits
  62. GRB 220412B: Swift-BAT refined analysis
  63. Konus-Wind detection of GRB 220412B
  64. GRB 220412B: Fermi GBM observation
  65. Konus-Wind detection of GRB 220403C
  66. GRB 220412A: GRANDMA observations
  67. GRB 220412A: BOOTES-network optical upper limits
  68. GRB 220412B: BOOTES-1 optical upper limit
  69. GRB 220412A: Swift-BAT refined analysis
  70. GRB 220412A: RATIR Observations of the Fading Afterglow
  71. GRB 220412B: Swift-XRT observations
  72. IPN triangulation of short/soft GRB 220406A
  73. Swift GRB 220412B: Global MASTER-Net observations report
  74. GRB 220408A: HCT optical upper limit
  75. GRB 220412B: GIT optical upper limit
  76. GRB 220412A: MITSuME Akeno optical upper limits
  77. Correction to GCN 31888: GRB 220412A: Swift-XRT refined Analysis
  78. GRB 220412B: MITSuME Akeno optical upper limits
  79. GRB 220412A: Swift-XRT refined Analysis
  80. GRB 220412A: Enhanced Swift-XRT position
  81. GRB 220412B: Swift detection of a short burst
  82. GRB 220412A: Swift/UVOT Upper Limits
  83. GRB 220408A: GRANDMA observations
  84. GRB 220412A: RATIR Afterglow Candidate
  85. GRB 220412A: Swift detection of a burst
  86. Swift GRB220412.28: Global MASTER-Net observations report
  87. IPN triangulation of GRB 220403C
  88. GRB 220403B: Swift/UVOT Detection
  89. GRB 220408A: Swift-BAT refined analysis
  90. GRB 220408A: RATIR Optical and NIR Observations
  91. GRB 220403B: 1.3m DFOT Optical upper limit
  92. GRB 220408A: 1.3m DFOT Optical upper limit
  93. GRB 220403C: Swift-XRT observations
  94. GRB 220408A: redshift lower limit estimating
  95. GRB 220408A: NOT optical observations and archival detection
  96. GRB 220408A: LCO Optical Afterglow Detection
  97. GRB 220408A: Swift-XRT refined Analysis
  98. GRB 220403C: Swift ToO observations
  99. GRB 220408A: BOOTES-5/JGT optical afterglow detection
  100. GRB 220408A: GIT optical upper limit

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Download all Circulars as a .tar.gz archive (updated once a day):
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