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"

38354 results found.

  1. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  2. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  3. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  4. GRB 080822B: Swift detection of a burst
  5. GRB080818B: GLAST Burst Monitor detection
  6. Third event from SGR 0501+4516
  7. New Soft Gamma Repeater 0501+4516 was GRB 080822
  8. GRB 080822: Swift detection of a short burst
  9. GLAST Burst Monitor detection of a GRB: 080816B
  10. GLAST Burst Monitor detection of GRB 080818
  11. GLAST Burst Monitor detection of GRB080817B
  12. GLAST Burst Monitor detection of GRB 080817
  13. GLAST Burst Monitor detection of GRB080816
  14. GRB080810 - optical observations
  15. GRB080810: optical observations
  16. GLAST Burst Monitor detection of GRB 080812
  17. Radio detection of GRB 080810 with the VLA
  18. GRB 080810: Konus-Wind and Swift/BAT joint spectral analysis
  19. GLAST Burst Monitor detection of GRB 080810
  20. GRB 080810: Liverpool and Faulkes North observations
  21. GRB 080810: RTT150 optical observations
  22. GRB080810: MITSuME optical observation
  23. GRB 080810: Swift/UVOT Refined Analysis
  24. GRB 080810: optical observations
  25. GRB 080810: Liverpool Telescope observations
  26. GRB 080810: Kanazawa optical observation
  27. GRB 080810: OSN follow-up
  28. GRB 080810: Observations from NOT
  29. GRB 080810: Swift-XRT Team refined analysis
  30. GRB 080810: Enhanced Swift-XRT position
  31. GRB 080810: KANATA optical-NIR observation, update
  32. GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
  33. GRB 080810: Keck/HIRES Spectroscopy
  34. GRB 080810 : optical observation with KANATA
  35. GRB 080810: Swift detection of a burst with a bright optical afterglow
  36. GRB 080723B: GROND upper limits
  37. GRB 080723B: XMM-Newton observation
  38. GRB 080805: VLT redshift update
  39. GRB 080805: Faulkes Telescope South optical observations
  40. GRB 080804: GROND observations
  41. GRB 080727B: Late VLT imaging
  42. GRB 080805: Swift-XRT Refined Analysis
  43. GRB 080805: Swift/UVOT Upper Limits
  44. GRB 080804: Swift-XRT Refined Analysis
  45. GRB 080804: Swift/UVOT Refined Analysis
  46. GRB 080804: Enhanced Swift-XRT position
  47. GRB080804: Gemini South redshift confirmation
  48. GRB 080804: Faulkes Telescope South observations
  49. GRB080805 optical limit by "Pi of the Sky"
  50. GRB 080805: VLT redshift
  51. GRB 080805: GROND detection of possible afterglow
  52. GRB 080805: Swift detection of a burst
  53. GRB 080804: UVES redshift
  54. GRB 080804: Swift detection of a burst with optical afterglow
  55. GRB 080804: ROTSE-III Detection of Optical Counterpart
  56. GRB 080802: Swift/UVOT Upper Limits
  57. GRB 080802: Swift-XRT Refined Analysis
  58. GRB 080802: Swift detection of a probable burst
  59. GRB 080727C: Suzaku WAM observation of the prompt emission
  60. GRB 080727B: KAIT photometry and an early lightcurve break
  61. GRB 080727B: GROND redshift limit
  62. GRB 080727C: Swift/UVOT Upper Limits
  63. Konus-Wind observation of GRB 080727B
  64. GRB 080727C: Swift XRT refined analysis
  65. GRB 080727C: Liverpool Telescope observations
  66. GRB 080727A: VLT upper limits
  67. GRB 080727C: Enhanced Swift-XRT position
  68. GRB 080727B: REM NIR afterglow prompt detection
  69. GRB 080727C: Swift detection of a burst
  70. Swift detection of XTE J1701-407
  71. GRB 080727B: Swift/UVOT Upper Limits
  72. BAT Trigger 318150 is not a GRB
  73. GRB 080727B: Swift-XRT refined analysis
  74. GRB 080727A: Swift-XRT refined analysis
  75. GRB080727A: Swift/UVOT Upper Limits
  76. GRB 080727B: Enhanced Swift-XRT position
  77. GRB 080727A: Enhanced Swift-XRT position
  78. GRB 080727B: KAIT observations
  79. GRB 080727B: REM prompt observations
  80. GRB 080727B: Swift detection of a bright burst
  81. GRB 080727: Swift detection of a burst
  82. GRB 080726: GRB Localization by SuperAGILE
  83. GRB 080723A: optical upper limit
  84. GRB080723B: Swift/UVOT Upper Limits
  85. GRB 080725: REM prompt observations
  86. Konus-Wind observation of GRB 080723B
  87. GRB 080725: Swift detection of a burst
  88. ATCA radio upper limit on GRB 080723B
  89. GRB 080723A: Swift/UVOT Upper Limits
  90. VLA radio upper limit on GRB 080721
  91. GRB 080723B - correction to flux conversion factor
  92. GRB 080723B - Swift-XRT refined analysis
  93. GRB 080723B - Swift-XRT position
  94. GRB 080723B: AGILE GRID and MCAL results
  95. GRB 080723B : Planned XMM-Newton observation
  96. GRB 080723A: Swift-XRT refined analysis
  97. GRB 080723B: Detection and Localization by SuperAGILE
  98. GRB 080723B : a long GRB detected with INTEGRAL
  99. GRB 080723: Enhanced Swift-XRT position
  100. GRB 080723: Swift detection of a burst

Advanced

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