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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"

19715 results found.

  1. GRB 220521A: Swift detection of a burst
  2. GRB 220514A: AstroSat CZTI detection
  3. Continued Chandra monitoring of GW170817 at ~4.8 yr post-merger
  4. GRB 220518A: Swift/UVOT Detection
  5. GRB 220518A: Enhanced Swift-XRT position
  6. GRB 220518A: Swift detection of a burst
  7. GRB 220514A: MITSuME Akeno optical observation
  8. GRB 220514A: GRANDMA Optical Afterglow Observations
  9. Fermi trigger No 674397342: Global MASTER-Net observations report
  10. GRB 220514B: Swift-XRT observations
  11. GRB 220511A: Swift-XRT afterglow detection
  12. Fermi-LAT Gamma-ray Observations of IceCube-220513A
  13. GRB 220514B: Tiled Swift observations
  14. IceCube-220513A: No significant detection in HAWC
  15. GRB 220514A: MeerLICHT optical afterglow candidate
  16. IceCube-220509A: No significant detection in HAWC
  17. GRB 220511A: Swift ToO observations
  18. Fermi-LAT Gamma-ray Observations of IceCube-220509A
  19. GRB 220506A: MITSuME Akeno optical upper limits
  20. GRB 220506A: GIT optical upper limit.
  21. GRB 220508A: Fermi GBM Final Real-time Localization
  22. GRB 220506A: Tiled Swift observations
  23. GRB 220430A: Nanshan/NEXT optical upper limit
  24. GRB 220430A: Nanshan/HMT optical upper limit
  25. GRB 220430A: GIT optical upper limits
  26. IPN triangulation of GRB 220423A
  27. Fermi-LAT Gamma-ray Observations of IceCube-220501A
  28. GRB 220427A: GRANDMA Early Optical Afterglow Detection
  29. GRB 220501A: GRANDMA/TJML Optical Observations
  30. GRB 220430A: Mondy and AbAO optical upper limits
  31. GRB 220430A: MeerLICHT optical upper limits
  32. GRB 220430A: Enhanced Swift-XRT position
  33. GRB 220430A: Swift detection of a burst or Swift J0630.4+0932
  34. GRB 220427A: Swift-BAT refined analysis
  35. GRB 220427A: VLT/X-shooter photometry
  36. GRB 220427A: Enhanced Swift-XRT position
  37. GRB 220426A: Tiled Swift observations
  38. GRB 220427A: Swift detection of a burst with an optical counterpart
  39. IPN triangulation of GRB 220426A
  40. Fermi-LAT Gamma-ray Observations of IceCube-220425A
  41. Correction to 31937: GRB 220421B: Detection by VZLUSAT-2
  42. Fermi-LAT Gamma-ray Observations of IceCube-220424A
  43. Fermi-LAT Gamma-ray Observations of IceCube-220421A
  44. GRB 220418B: Swift ToO observations
  45. GRB 220412B: Swift/UVOT Upper Limits
  46. GRB 220408B: Fermi GBM observation
  47. GRB 220412B: TNG optical observations
  48. GRB 220412A: GRANDMA observations
  49. GRB 220412A: Continued RATIR Observations and Steepening of the Light Curve
  50. GRB 220412A: RATIR Observations of the Fading Afterglow
  51. GRB 220412B: Swift-XRT observations
  52. GRB 220408B: Fermi-LAT detection
  53. IPN triangulation of short/soft GRB 220406A
  54. GRB 220412B: GIT optical upper limit
  55. GRB 220412A: MITSuME Akeno optical upper limits
  56. GRB 220412B: MITSuME Akeno optical upper limits
  57. GRB 220412A: Enhanced Swift-XRT position
  58. GRB 220412B: Swift detection of a short burst
  59. GRB 220412A: Swift/UVOT Upper Limits
  60. GRB 220408A: GRANDMA observations
  61. GRB 220403B: GRANDMA observations
  62. GRB 220412A: RATIR Afterglow Candidate
  63. GRB 220412A: Swift detection of a burst
  64. IPN triangulation of GRB 220403C
  65. GRB 220403B: Swift/UVOT Detection
  66. GRB 220408A: RATIR Optical and NIR Observations
  67. GRB 220408A: 1.3m DFOT Optical upper limit
  68. GRB 220408A: NOT optical observations and archival detection
  69. GRB 220403C: Swift ToO observations
  70. GRB 220408A: BOOTES-5/JGT optical afterglow detection
  71. GRB 220408A: GIT optical upper limit
  72. GRB 220408A: Fermi GBM observation
  73. GRB 220408A: Swift/UVOT Detection
  74. GRB 220408B: Fermi GBM Final Localization
  75. GRB 220408A: Xinglong-2.16m optical upper limit
  76. GRB 220408A: Enhanced Swift-XRT position
  77. GRB 220408A: Swift detection of a burst with an optical counterpart, possibly associated with M51
  78. GRB 220408A: Fermi GBM Final Real-time Localization
  79. GRB 220403B: Mondy optical upper limit
  80. GRB 220403B: Kitab optical observations
  81. Fermi-LAT Gamma-ray Observations of IceCube-220405A
  82. GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  83. GRB 220403B: LBT observations
  84. GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
  85. GRB 220403A: Tautenburg observations
  86. GRB 220403B: Swift detection of a burst with an optical counterpart
  87. Swift Trigger 1100848 is likely not a GRB
  88. Fermi GRB 220330A: Global MASTER-Net observations report
  89. GRB 220325A: GRANDMA observations
  90. GRB 220325A: Swift/UVOT Upper Limits
  91. GRB 220325A: Tautenburg observations
  92. GRB 220325A: Swift-XRT refined Analysis
  93. GRB 220325A: Enhanced Swift-XRT position
  94. GRB 220325A: MASTER Global Robotic Net optical observations
  95. GRB 220325A: Swift detection of a burst
  96. GRB 220319A: GRANDMA observations
  97. GRB 220319A: MITSuME Akeno optical upper limits
  98. GRB220319A: Optical observations from NOT
  99. GRB 220319A: Mondy optical uper limit
  100. GRB 220319A: Enhanced Swift-XRT position

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