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"

6792 results found.

  1. GRB 090323: GROND Detection of the Afterglow and Photo-z
  2. Fermi GBM and LAT detections of GRB 090323
  3. GRB 090313: VLT spectroscopy
  4. GRB 090313: Light curve steepening
  5. GRB 090313 - PAIRITEL NIR detections
  6. GRB 090313 optical observations
  7. GRB 090313: Swift-XRT refined analysis
  8. GRB 090313: Faulkes Telescope North observations
  9. GRB 090306B: Confirmation of the X-ray afterglow
  10. GRB 090309: Swift-XRT refined analysis
  11. GRB 090308: Gemini GMOS Observations
  12. GRB 090308: Swift-XRT refined analysis
  13. GRB 090306B: Possible XRT afterglow
  14. GRB 090307: Swift-XRT afterglow confirmation and analysis
  15. GRB 090305: Swift-XRT refined analysis
  16. Ongoing activity of AXP/SGR 1E1547.0-5408
  17. GRB090217: Fermi-LAT Detection
  18. GRB 090205: Swift-XRT refined analysis
  19. GRB 090201: Swift-XRT refined analysis
  20. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  21. GRB090113: MAGIC telescope GeV observation
  22. GRB 090126A: Swift/UVOT Upper Limits
  23. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  24. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  25. GRB 090126A: Swift-XRT Refined Analysis
  26. GRB 090123: Swift XRT refined analysis
  27. AXP 1E1547.0-5408: Fermi GBM observations
  28. GRB 090118: Swift-XRT observations
  29. GRB090118 Swift/UVOT upper limits
  30. GRB090117 Swift/UVOT upper limits
  31. GRB090117: Swift-XRT detection of a possible candidate afterglow
  32. GRB090102: MAGIC telescope GeV observation
  33. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  34. GRB 090113: Swift-XRT refined analysis
  35. GRB 090112B: Fermi GBM Detection
  36. GRB 090111: Swift-XRT refined analysis
  37. GRB 090107B: Swift XRT afterglow confirmation
  38. GRB 090107B: Swift-XRT detection of possible afterglow
  39. Fermi/GBM detection of GRB 081226A
  40. Fermi/GBM detection of GRB 081225
  41. GRB 090102: Swift XRT refined analysis
  42. GRB 081230, Swift-BAT refined analysis
  43. GRB081230: Swift-XRT refined analysis
  44. GRB 081226B: Fermi GBM observation
  45. GRB 081228, Swift-BAT refined analysis
  46. GRB 081228: Swift-XRT Team refined analysis
  47. GRB 081226B: Swift XRT and UVOT upper limits
  48. GRB 081226: Swift-XRT refined analysis
  49. GRB 081226: Gemini-South imaging
  50. GRB 081224: Swift-XRT observation
  51. GRB 081224: Fermi GBM Detection & LAT Localization
  52. GRB 081222:Optical afterglow observation
  53. GRB081215A: Fermi-LAT observations
  54. GRB 081211B: Further Swift-XRT analysis
  55. GRB 081215B: Fermi GBM detection
  56. GRB 081211B - possibly a short burst with extended emission
  57. Possible GRB 081211B: Swift/UVOT Upper Limits
  58. Possible GRB 081211B - Swift-XRT analysis
  59. GRB 081211: Swift XRT refined analysis
  60. GRB 081210: Swift-XRT refined analysis
  61. GRB 081206C: Fermi GBM detection
  62. GRB 081128: Optical afterglow observations
  63. GRB081203A: Radio upper limit at 15 GHz
  64. GRB 081204: Swift XRT afterglow confirmation
  65. Swift-XRT observations of GRB 081203B
  66. GRB081203A: Swift-XRT refined analysis
  67. GRB 081203B: Swift-XRT candidate afterglow.
  68. GRB 081130B: MASTER prompt optical observations
  69. GRB 081130B: Fermi GBM detection
  70. GRB 081122B: Fermi GBM Detection
  71. GRB 081128: Swift-XRT refined analysis
  72. GRB 081127: Swift-XRT refined analysis
  73. GRB 081126: Swift-XRT refined analysis
  74. GRB 081121: Swift-XRT refined analysis
  75. GRB 081118: Swift-XRT refined analysis
  76. GRB 081118: Swift UVOT Upper Limits
  77. GRB 081109A: confirmation of possible detection host galaxy
  78. Further Swift-XRT observations of the probable GRB 081105.
  79. GRB 081025: Swift-XRT further analysis
  80. GRB 081024B: Swift-XRT late-time observations
  81. GRB 081109A: Swift-XRT refined analysis
  82. GRB 081028 - PAIRITEL NIR detection
  83. GRB 081024C: Fermi Gamma-ray Burst Monitor detection
  84. GRB 081104: refined XRT analysis
  85. Fermi Detection of GRB 081102
  86. GRB 081102: Swift-XRT refined analysis
  87. GRB 081101 (or SGR 0623-0006 ): Fermi GBM detection
  88. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis
  89. GRB 081024B: new Swift-XRT observations
  90. GRB 081029: Swift-BAT refined analysis
  91. GRB081029: Swift XRT refined analysis
  92. GRB 081029: UVES/VLT Absorption Redshift
  93. GRB 081028B: Fermi GBM detection
  94. GRB 081028: Swift-XRT refined analysis
  95. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow (Corrected)
  96. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow
  97. GRB 081024B: Swift-XRT further observations
  98. Swift UVOT observations of GRB081024B
  99. GRB 081025: Swift-XRT position
  100. GRB 081024B: Swift-XRT observations

Advanced

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