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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"

21525 results found.

  1. IPN triangulation of GRB 220426A
  2. GRB 220426C: Swift/BAT-GUANO detection outside the coded FOV (short)
  3. GRB 220426A: Swift/BAT-GUANO detection outside the coded FOV
  4. GRB 220423A: Swift/BAT-GUANO detection outside the coded FOV
  5. GRB 220421A: Fermi GBM observation
  6. GRB 220421A: Swift/BAT-GUANO detection outside the coded FOV
  7. GRB 220418B: Swift-XRT observations
  8. GRB 220418B Fermi GBM observation
  9. GRB 220420A: Swift/BAT-GUANO detection outside the coded FOV
  10. GRB 220403C: Further Swift-XRT observations
  11. GRB 220418B: Swift ToO observations
  12. GRB 220417A: Fermi GBM detection
  13. GRB 220418B: Swift/BAT-GUANO refined location of a short burst
  14. GRB 220418B: Swift/BAT-GUANO candidate arcminute localization of a short burst
  15. GRB 220417A: Swift/BAT-GUANO detection outside the coded FOV
  16. GRB 220412B: Swift/UVOT Upper Limits
  17. GRB 220412B: Swift-BAT refined analysis
  18. Konus-Wind detection of GRB 220412B
  19. GRB 220412B: Fermi GBM observation
  20. Konus-Wind detection of GRB 220403C
  21. GRB 220412A: GRANDMA observations
  22. GRB 220412A: BOOTES-network optical upper limits
  23. GRB 220412B: BOOTES-1 optical upper limit
  24. GRB 220412A: Swift-BAT refined analysis
  25. GRB 220412A: RATIR Observations of the Fading Afterglow
  26. GRB 220412B: Swift-XRT observations
  27. IPN triangulation of short/soft GRB 220406A
  28. Swift GRB 220412B: Global MASTER-Net observations report
  29. GRB 220408A: HCT optical upper limit
  30. GRB 220412B: GIT optical upper limit
  31. GRB 220412A: MITSuME Akeno optical upper limits
  32. Correction to GCN 31888: GRB 220412A: Swift-XRT refined Analysis
  33. GRB 220412B: MITSuME Akeno optical upper limits
  34. GRB 220412A: Swift-XRT refined Analysis
  35. GRB 220412A: Enhanced Swift-XRT position
  36. GRB 220412B: Swift detection of a short burst
  37. GRB 220412A: Swift/UVOT Upper Limits
  38. GRB 220408A: GRANDMA observations
  39. GRB 220412A: RATIR Afterglow Candidate
  40. GRB 220412A: Swift detection of a burst
  41. Swift GRB220412.28: Global MASTER-Net observations report
  42. IPN triangulation of GRB 220403C
  43. GRB 220403B: Swift/UVOT Detection
  44. GRB 220408A: Swift-BAT refined analysis
  45. GRB 220408A: RATIR Optical and NIR Observations
  46. GRB 220403B: 1.3m DFOT Optical upper limit
  47. GRB 220408A: 1.3m DFOT Optical upper limit
  48. GRB 220403C: Swift-XRT observations
  49. GRB 220408A: redshift lower limit estimating
  50. GRB 220408A: NOT optical observations and archival detection
  51. GRB 220408A: LCO Optical Afterglow Detection
  52. GRB 220408A: Swift-XRT refined Analysis
  53. GRB 220403C: Swift ToO observations
  54. GRB 220408A: BOOTES-5/JGT optical afterglow detection
  55. GRB 220408A: GIT optical upper limit
  56. GRB 220408A: Fermi GBM observation
  57. GRB 220408A: Swift/UVOT Detection
  58. GRB 220408A: Xinglong-2.16m optical upper limit
  59. GRB 220408A: Enhanced Swift-XRT position
  60. GRB 220408A: KAIT Optical Observations
  61. GRB 220408A: Swift detection of a burst with an optical counterpart, possibly associated with M51
  62. GRB 220403B: 1.5m OSN optical observation
  63. GRB 220404A: Swift-BAT refined analysis
  64. GRB 220403B: Swift-BAT refined analysis
  65. GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  66. GRB 220403B: Fermi GBM detection
  67. GRB 220404A: Swift detection of a burst
  68. GRB 220403B: Swift-XRT refined Analysis
  69. Swift GRB 220403B: Global MASTER-Net observations report
  70. GRB 220403C (or A): Swift/BAT-GUANO detection outside the coded FOV
  71. GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
  72. GRB 220403A: Tautenburg observations
  73. GRB 220403B: optical detection by D50
  74. GRB 220403B: Swift detection of a burst with an optical counterpart
  75. GRB 220401A: Swift/BAT-GUANO detection outside the coded FOV
  76. Swift Trigger 1100848 is likely not a GRB
  77. Swift GRB220402.16: Global MASTER-Net observations report
  78. GRB 220325A: GRANDMA observations
  79. GRB 220325A: Swift/UVOT Upper Limits
  80. GRB 220325A: Swift-BAT refined analysis
  81. GRB 220325A: Tautenburg observations
  82. GRB 220325A: LCO Optical Upper Limits
  83. GRB 220325A: Swift-XRT refined Analysis
  84. GRB 220325A: 1.3m DFOT Optical upper limit
  85. Fermi GBM Sub-Threshold Detection of GRB 220325A
  86. GRB 220325A: Enhanced Swift-XRT position
  87. GRB 220325A: MASTER Global Robotic Net optical observations
  88. GRB 220325A: Swift detection of a burst
  89. GRB 220319A: GRANDMA observations
  90. GRB 220319A: Swift-BAT refined analysis
  91. GRB 220317A: Fermi GBM detection
  92. GRB 220319A: MITSuME Akeno optical upper limits
  93. GRB220319A: Optical observations from NOT
  94. GRB 220319A: LCO Optical Upper Limit
  95. GRB 220319A: Mondy optical uper limit
  96. GRB 220319A: Swift-XRT refined Analysis
  97. GRB 220319A: Enhanced Swift-XRT position
  98. GRB 220319A: MASTER Global Robotic Net optical observations
  99. GRB 220319A: Swift detection of a burst
  100. GRB 220317A: Swift/BAT-GUANO detection outside the coded FOV

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