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"

21769 results found.

  1. GRB 100514A: Swift detection of a burst
  2. GRB 100513A: Swift/UVOT upper limits
  3. GRB 100513A, RIMOTS optical upper limits
  4. GRB 100513A: Enhanced Swift-XRT position
  5. GRB 100513A: SARA-N Upper Limit
  6. GRB 100513A: Swift detection of a burst
  7. GRB 100510A: Fermi GBM detection/observation
  8. GRB 100511A: Fermi GBM detection/observation
  9. GRB 100511A: Super-LOTIS early observations
  10. Swift-BAT trigger 421695 is likely not astrophysical
  11. GRB100504A: Optical upper limits at IAO
  12. GRB 100511A, RIMOTS optical upper limits
  13. Trigger 421695: Swift detection of a possible burst
  14. GRB100503A: Suzaku WAM observation of the prompt emission
  15. GRB 100508A: GROND Detection of the optical afterglow
  16. GRB 100508A: Enhanced Swift-XRT position
  17. GRB100508A: Swift/UVOT Detection of the Afterglow
  18. GRB 100508A: ROTSE-III Optical Limits
  19. GRB 100508A: Swift detection of a burst
  20. GRB 100418A: Keck imaging
  21. GRB 100418A: RTT150 optical observations
  22. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  23. GRB 100504A: Swift/UVOT Observations
  24. GRB 100504A: Enhanced Swift-XRT position
  25. GRB 100504A: GROND Upper limits
  26. GRB 100504A: SARA-South Upper Limit
  27. GRB 100503A: Fermi GBM detection
  28. GRB 100504A: Swift detection of a burst
  29. INTEGRAL observations of Swift GRB trigger 421072
  30. GRB100423A : Suzaku WAM observation of the prompt emission
  31. Trigger 421072: Possible Swift detection of a GRB or transient
  32. GRB 100420A: Terskol optical upper limit
  33. GRB 100427A: Swift XRT and UVOT Upper Limits
  34. GRB 100414A : EVLA Radio Detection
  35. GRB 100414A : WSRT Radio Detection
  36. Konus-Wind observation of GRB 100423A
  37. GRB 100423A: CrAO optical observations
  38. GRB 100418A: Terskol optical observations
  39. GRB 100424A: CrAO optical observations
  40. GRB 100424A: NIR Afterglow Confirmation
  41. GRB 100424A: Gemini/NIRI H-band observations
  42. GRB100425A: Swift/UVOT Upper Limits
  43. GRB 100424A: Swift/UVOT Upper Limits
  44. GRB 100424A: Liverpool Telescope Upper Limits
  45. GRB 100425A: Enhanced Swift-XRT position
  46. GRB 100425A: GROND afterglow observation
  47. GRB 100424A: Gemini/NIRI Candidate Afterglow
  48. GRB 100424A: D50 optical limits
  49. GRB 100425A: candidate optical afterglow from the VLT
  50. GRB100424A: MITSuME optical upper limits
  51. GRB100423A: MITSuME optical upper limits
  52. GRB 100424A : Lulin early z'-band upper limit
  53. GRB 100424A: GROND Upper Limits
  54. GRB 100424A: PAIRITEL NIR Upper Limits
  55. GRB 100425A: Swift detection of a burst
  56. GRB 100424A: NOT optical observations
  57. GRB 100424A: Enhanced Swift-XRT position
  58. GRB 100424A: Swift detection of a burst
  59. GRB 100420A: GRT Optical Observation
  60. Swift Trigger 420256: D50 optical limits
  61. GRB 100423B: Fermi GBM detection
  62. Swift Trigger 420256: IAC80 R-band observations
  63. Swift Trigger 420256: BOOTES-2 observations
  64. Swift Trigger 420256: ROTSE-III Optical Limits
  65. Trigger 420256: Swift detection of a possible GRB
  66. GRB 100423A: GROND discovery of afterglow
  67. GRB100418A: REM possible afterglow detection
  68. GRB 100418A: Continuing Swift/UVOT Observations
  69. GRB100420A: MITSuME optical upper limits
  70. GRB 100414A: CFHT optical observations
  71. GRB 100420A: Swift/UVOT Upper Limits
  72. GRB 100420A: Enhanced Swift-XRT position
  73. GRB 100418A: SARA second epoch
  74. GRB 100420A: SARA Upper Limits
  75. GRB 100418A: optical observations
  76. GRB 100418A: SMA submm detection
  77. GRB 100420A: ROTSE-III Optical Limits
  78. GRB 100420A: Swift detection of a burst
  79. GRB 100418A: Swift/UVOT Observations
  80. GRB 100418A: Gemini-N redshift confirmation
  81. GRB100418A: VLT/X-shooter redshift and photometry
  82. GRB 100418A: SARA observations
  83. GRB 100418A: GROND observations; missing author list added
  84. GRB 100418A: GROND observations
  85. GRB 100418A: Enhanced Swift-XRT position
  86. GRB 100418A: ROTSE-III Optical Limits
  87. GRB 100418A: Swift detection of a burst with a possible optical afterglow
  88. GRB 100414A: Suzaku WAM observation of the prompt emission
  89. GRB 100414A: Swift/UVOT Observations
  90. GRB 100414A: GROND Detection of the Optical Afterglow
  91. GRB 100414A: Gemini-N candidate and redshift
  92. GRB 100414A: Enhanced Swift-XRT position of candidate afterglow
  93. GRB 100413A: Suzaku WAM observation of the prompt emission
  94. GRB 100414A: Palomar Transient Factory Observations
  95. GRB 100414A: Swift-XRT detection of a possible X-ray afterglow
  96. Konus-Wind observation of GRB 100414B
  97. GRB 100414A: Fermi GBM detection
  98. GRB100414A: Fermi LAT detection
  99. GRB 100413B : Swift detection of a burst
  100. GRB 100413A: GROND Upper limits

Advanced

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