Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

27391 results found.

  1. GRB 090404: Swift detection of a burst
  2. GRB 090401A: Suzaku WAM observation of the prompt emission
  3. GRB 090401B: Suzaku WAM observation of the prompt emission
  4. GRB 090401B: Xinglong TNT optical Upper Limit
  5. GRB 090401B: VLA radio upper limit
  6. GRB 090401B: Upper limits of MITSuME optical observation
  7. GRB090401B, RIMOTS optical upper limits
  8. GRB 090401B: AGILE refined analysis
  9. GRB 090401B: Swift XRT Refined Analysis
  10. GRB 090331: Fermi GBM detection
  11. Konus-Wind observation of GRB 090401A
  12. GRB 090401B: Enhanced Swift-XRT position
  13. AGILE Gamma-ray detection of GRB 090401B
  14. GRB 090401B: Swift-BAT refined analysis
  15. GRB 090401B: Swift detection of a burst
  16. GRB 090328B: MASTER-Irkutsk prompt optical short burst observations
  17. GRB 090401, Swift-BAT refined analysis
  18. GRB 090323: Further TLS detections - a break?
  19. GRB 090324: Suzaku WAM observation of the prompt emission
  20. GRB 090328: Radio afterglow detection
  21. GRB 090326: Fermi GBM detection
  22. GRB 090328: Fermi GBM Spectral Analysis
  23. GRB 090328B: Fermi GBM Detection
  24. GRB 090330: Fermi GBM detection
  25. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  26. GRB 090328: Swift XRT refined analysis
  27. GRB090323: Optical observations from NOT
  28. GRB 090328: Swift UVOT observations
  29. GRB 090328: Updated position/optical afterglow candidate
  30. Fermi LAT and GBM detections of GRB090328
  31. GRB 090323: Radio afterglow detection
  32. GRB 090327: Fermi GBM detection
  33. GRB 090320B: MASTER-Net prompt optical observations
  34. GRB 090323: Fermi GBM Spectral Analysis
  35. GRB 090323: UVOT Detection of Afterglow
  36. GRB 090324: SuperAGILE Localization of a Long GRB
  37. GRB 090323: P60 Afterglow Confirmation
  38. GRB 090323: GROND Detection of the Afterglow and Photo-z
  39. GRB 090323: Possible XRT Counterpart
  40. GRB 090320C: Fermi GBM Detection
  41. GRB 090320B: Fermi GBM detection.
  42. GRB 090319: Fermi GBM detection
  43. GRB 090320A: Fermi GBM detection
  44. Further 15GHz observations of GRB090313
  45. X-shooter observations of GRB 090313
  46. A bright burst from AXP 1E 1547.0-5408/SGR J1550-5418
  47. GRB 090315: Suzaku WAM observation of the prompt emission
  48. GRB090313: radio detection with the VLA
  49. IPN Triangulation of GRB090315 and Tupi Detection of Muon Increase
  50. Further radio observation of GRB 090313
  51. GRB 090313: detection with CARMA in 3mm band
  52. GRB090305B: MASTER-net prompt optical short burst observations
  53. GRB 090313: MITSuME Okayama observation
  54. GRB 090313: Additional Gemini-S photometry
  55. GRB 090313: TAROT La Silla observatory optical detection
  56. GRB 090313: Zadko Telescope observations
  57. GRB 090313 optical observations
  58. GRB 090313: Ongoing plateau phase
  59. GRB 090313: Swift-XRT refined analysis
  60. GRB 090313: Swift/UVOT upper limits
  61. GRB 090313: Swift-BAT refined analysis
  62. GRB 090313, GROND observations
  63. GRB 090309, Swift-BAT lag analysis
  64. Swift trigger 346250 is probably not a burst
  65. GRB090310: Fermi GBM detection
  66. GRB 090205: Zadko Telescope late-time observations
  67. GRB 090309A: GROND upper limits
  68. GRB 090307A: TAROT Calern observatory optical observations
  69. GRB 090309: Swift/UVOT Upper Limits
  70. GRB090305B: Fermi GBM detection
  71. GRB 090309B: Fermi GBM detection
  72. GRB 090309: Swift-XRT refined analysis
  73. GRB 090309: Enhanced Swift-XRT position
  74. GRB 090309, Swift-BAT refined analysis
  75. GRB 090308: GROND observations
  76. GRB 090308: Gemini GMOS Observations
  77. GRB 090309: Swift detection of a burst
  78. GRB 090308B: Fermi GBM detection
  79. GRB 090308: Swift/UVOT Upper Limits
  80. GRB 090307B: Fermi GBM detection
  81. GRB 090306C: Fermi GBM detection
  82. GRB 090307: GROND Upper Limits
  83. GRB 090306B: GROND Upper Limits
  84. GRB 090308: Swift-XRT refined analysis
  85. Radio observation of GRB 090201 with ATCA
  86. Radio observation of GRB 090117 with ATCA
  87. Radio observation of GRB 081226b with ATCA
  88. Radio observation of GRB 081226a with ATCA
  89. Radio observation of GRB 081007 with ATCA
  90. GRB 090308: Swift-BAT refined analysis
  91. GRB 090308: Swift detection of a burst
  92. GRB 090306B: Possible XRT afterglow
  93. GRB 090307: Swift-XRT afterglow confirmation and analysis
  94. GRB 090307: Swift-BAT refined analysis of trigger 345551
  95. GRB 090306B: Burst detection from Swift-BAT slew data
  96. Swift Trigger 345551 is probably not a GRB
  97. IPN localization of short GRB 090305C
  98. GRB 090306: Swift detection of a possible burst
  99. GRB 090305: Swift/UVOT Upper Limits
  100. GRB 090305: Swift-XRT refined analysis

Advanced

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