Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

26040 results found.

  1. GRB 220907A: Swift detection of a burst
  2. Swift GRB220907.59: Global MASTER-Net observations report
  3. GRB 220831A: Swift-UVOT Upper Limits
  4. GRB 220831A: DECam detection of a possible optical counterpart
  5. GRB 220831A, VLT/HAWK-I near-infrared observations
  6. GRB 220831A: Fermi GBM observation
  7. GRB 220831A: Swift-XRT observations
  8. GRB 220831A: Swift ToO observations
  9. GRB 220831A: Swift/BAT-GUANO localization of a short burst
  10. Konus-Wind detection of GRB 220826A
  11. GRB 220826A: Swift-BAT refined analysis
  12. GRB 220826A: Fermi GBM observation
  13. GRB 220826A: Swift-XRT refined Analysis
  14. GRB 220825A: Fermi GBM observation
  15. GRB 220826A: Lesedi optical afterglow detection
  16. GRB 220826A: Swift/UVOT Detection
  17. GRB 220826A: iTelescope optical afterglow observations
  18. Swift GRB 220826A: Global MASTER-Net observations report
  19. GRB 220826A: Enhanced Swift-XRT position
  20. GRB 220826A: Swift detection of a burst with an optical counterpart
  21. GRB 220825A: Swift/BAT-GUANO detection
  22. GRB 220823A: Fermi GBM detection
  23. GRB 220823A: Swift/BAT-GUANO detection of a short burst
  24. Konus-Wind detection of GRB 220813A
  25. GRB 220813A: VLT optical observations and possible host galaxy
  26. GRB 220813A: Swift/UVOT Detection
  27. GRB 220810A: Further Swift-XRT observations
  28. GRB 220813A: Swift-XRT refined Analysis
  29. Swift GRB 220813A: Global MASTER-Net observations report
  30. GRB 220813A: Enhanced Swift-XRT position
  31. GRB 220813A: Swift detection of a burst with an optical counterpart
  32. GRB 220810A: Swift-XRT observations
  33. GRB 220810A: Swift ToO observations
  34. GRB 220810A: MeerLICHT detection of two afterglow candidates
  35. GRB 220806A: Swift-BAT refined analysis
  36. GRB 220806A: Swift detection of a burst
  37. Swift GRB220806.76: Global MASTER-Net observations report
  38. Konus-Wind detection of GRB 220730A (short)
  39. GRB 220730A: Swift-BAT refined analysis
  40. GRB 220730A: Fermi GBM detection
  41. GRB 220730A: Swift-XRT afterglow detection
  42. GRB 220730A: Swift/UVOT Upper Limits
  43. GRB 220730A: Swift-XRT observations
  44. Swift GRB 220730A: Global MASTER-Net observations report
  45. GRB 220730A: Swift detection of a short hard burst
  46. GRB 220715B: VIRT Optical Upper Limit
  47. GRB 220711B: CALET Gamma-Ray Burst Monitor detection
  48. GRB 220715B: Swift-BAT refined analysis
  49. GRB220714B: UVOT detections
  50. GRB 220715B: Fermi GBM detection
  51. GRB 220715B: Swift-XRT refined Analysis
  52. GRB 220715B: Swift/UVOT Upper Limits
  53. GRB 220715B: Enhanced Swift-XRT position
  54. GRB 220715B: BOOTES-network optical upper limits
  55. Swift GRB 220715B: Global MASTER-Net observations report
  56. GRB 220715B: Prompt enhanced Swift-XRT position
  57. GRB 220715B: Swift detection of a burst
  58. GRB 220714B: Swift-BAT refined analysis
  59. GRB 220714B: Fermi GBM observation
  60. GRB 220714B: LCO Optical Observations
  61. GRB 220714B: Swift-XRT refined Analysis
  62. Swift/BAT Trigger 1116172 (=GRB 220714A) is not a real astrophysical event
  63. GRB 220714B: UVOT afterglow discovery
  64. GRB 220714B: Enhanced Swift-XRT position
  65. GRB 220714B: Swift detection of a burst
  66. GRB 220714A: Possible Swift detection of a burst
  67. GRB 220710A: Swift/UVOT Upper Limits
  68. GRB 220711C: Fermi GBM Observation
  69. GRB 220711B: 10.4 m GTC(+EMIR) observations
  70. GRB 220711B: 10.4 m GTC(+EMIR) observations
  71. GRB 220710A: Swift-XRT afterglow detection
  72. GRB 220711C: Swift/BAT-GUANO detection outside the coded FOV
  73. GRB 220711B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  74. GRB 220711B: GIT optical upper limits
  75. GRB 220712B: NOT optical afterglow confirmation
  76. GRB 220710A: Swift ToO observations
  77. GRB 220710A: Swift/BAT-GUANO arcminute localization
  78. GRB 220711B: Swift-BAT refined analysis
  79. IPN triangulation of GRB 220711C (short)
  80. GRB 220711B: Swift-XRT refined Analysis
  81. GRB 220711B: Swift/UVOT Upper Limits
  82. GRB 220711B: Enhanced Swift-XRT position
  83. GRB 220711B: Fermi GBM Detection
  84. GRB 220711B: NOT optical observations
  85. GRB 220711B: LCO Optical Upper Limits
  86. GRB 220711B: Swift detection of a burst
  87. GRB 220708B: GIT optical upper limits
  88. GRB 220708A: Swift-BAT refined analysis
  89. GRB 220708B: T193-OHP optical upper limit
  90. Konus-Wind detection of GRB 220708B
  91. GRB 220708B: CALET Gamma-Ray Burst Monitor detection
  92. GRB 220708B: Nanshan/NEXT optical upper limits
  93. GRB 220708A: Swift/UVOT Upper Limits
  94. GRB 220706A : NICER detection of re-brightening 1 day after the Swift trigger
  95. GRB 220708A: Swift-XRT refined Analysis
  96. GRB 220706A: Swift/UVOT Upper Limits
  97. GRB 220708B: Swift-XRT afterglow detection
  98. GRB 220708A: BOOTES-5/JGT early optical upper limit
  99. GRB 220706A: Swift-BAT refined analysis
  100. GRB 220708A: Enhanced Swift-XRT position

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov