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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"
  1. GRB 080822: Swift detection of a short burst
  2. GLAST Burst Monitor detection of a GRB: 080816B
  3. GLAST Burst Monitor detection of GRB 080818
  4. GLAST Burst Monitor detection of GRB080817B
  5. GLAST Burst Monitor detection of GRB 080817
  6. GLAST Burst Monitor detection of GRB080816
  7. GRB080810 - optical observations
  8. GRB080810: optical observations
  9. GLAST Burst Monitor detection of GRB 080812
  10. Radio detection of GRB 080810 with the VLA
  11. GRB 080810: RTT150 optical observations
  12. GRB 080810: Konus-Wind and Swift/BAT joint spectral analysis
  13. GLAST Burst Monitor detection of GRB 080810
  14. GRB 080810: Liverpool and Faulkes North observations
  15. GRB 080810: RTT150 optical observations
  16. GRB080810: MITSuME optical observation
  17. First GLAST Burst Monitor GRB Circulars
  18. GRB 080810: Swift/UVOT Refined Analysis
  19. GRB 080810: optical observations
  20. GRB 080810: Liverpool Telescope observations
  21. GRB 080810: D50 optical observation
  22. GRB 080810: Kanazawa optical observation
  23. GRB 080810: OSN follow-up
  24. GRB 080810: Observations from NOT
  25. GRB 080810: RTT150 optical observations
  26. GRB 080810: Swift-XRT Team refined analysis
  27. GRB 080810: Enhanced Swift-XRT position
  28. GRB 080810: KANATA optical-NIR observation, update
  29. GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
  30. GRB 080810: Keck/HIRES Spectroscopy
  31. GRB 080810, Swift-BAT refined analysis
  32. GRB 080810 : optical observation with KANATA
  33. GRB 080810: Swift detection of a burst with a bright optical afterglow
  34. GRB 080723B: GROND upper limits
  35. GRB 080723B: XMM-Newton observation
  36. GRB 080805: VLT redshift update
  37. GRB 080805: Faulkes Telescope South optical observations
  38. GRB 080804: GROND observations
  39. GRB 080727B: Late VLT imaging
  40. GRB 080804: ATCA Radio Observations
  41. GRB 080805: Swift-XRT Refined Analysis
  42. GRB 080805: Swift/UVOT Upper Limits
  43. GRB 080804: Swift-XRT Refined Analysis
  44. GRB 080804: Swift/UVOT Refined Analysis
  45. GRB 080805, Swift-BAT refined analysis
  46. GRB 080804, Swift-BAT refined analysis
  47. GRB 080804: Enhanced Swift-XRT position
  48. GRB080804: Gemini South redshift confirmation
  49. GRB 080804: Faulkes Telescope South observations
  50. GRB080805 optical limit by "Pi of the Sky"
  51. GRB 080805: VLT redshift
  52. GRB 080805: Afterglow confirmation
  53. GRB 080805: GROND detection of possible afterglow
  54. GRB 080805: Swift detection of a burst
  55. GRB 080804: UVES redshift
  56. GRB 080804: Swift detection of a burst with optical afterglow
  57. GRB 080804: ROTSE-III Detection of Optical Counterpart
  58. GRB 080802: Swift/UVOT Upper Limits
  59. GRB 080802: Swift-XRT Refined Analysis
  60. GRB 080802: UVI Telescope Upper Limit
  61. GRB 080802, Swift-BAT refined analysis
  62. GRB 080802: Swift detection of a probable burst
  63. GRB 080727C: Suzaku WAM observation of the prompt emission
  64. GRB 080727B: IR photometry
  65. GRB 080727A: Early IR observations
  66. GRB 080727C: TAROT Calern observatory optical observations
  67. GRB 080727B: KAIT photometry and an early lightcurve break
  68. GRB 080727B: GROND redshift limit
  69. GRB 080727C, Swift-BAT refined analysis
  70. GRB 080727C: Swift/UVOT Upper Limits
  71. Konus-Wind observation of GRB 080727B
  72. GRB 080727C: Swift XRT refined analysis
  73. GRB 080727C: Liverpool Telescope observations
  74. GRB 080727A: VLT upper limits
  75. GRB 080727C: Enhanced Swift-XRT position
  76. GRB 080727B: REM NIR afterglow prompt detection
  77. GRB080727C: RTT150 optical observations
  78. GRB 080727C: Swift detection of a burst
  79. Swift detection of XTE J1701-407
  80. GRB 080727B: Swift/UVOT Upper Limits
  81. BAT Trigger 318150 is not a GRB
  82. GRB 080727B: Swift-XRT refined analysis
  83. GRB 080727B, Swift-BAT refined analysis
  84. GRB 080727A, Swift-BAT refined analysis
  85. GRB 080727A: Swift-XRT refined analysis
  86. GRB080727A: Swift/UVOT Upper Limits
  87. GRB 080727B: Enhanced Swift-XRT position
  88. GRB 080727A: Enhanced Swift-XRT position
  89. GRB 080727B: KAIT observations
  90. GRB 080727B: REM prompt observations
  91. GRB 080727B: Swift detection of a bright burst
  92. GRB 080727: Swift detection of a burst
  93. GRB 080726: GRB Localization by SuperAGILE
  94. GRB 080725, Swift-BAT refined analysis
  95. GRB 080723A: optical upper limit
  96. GRB080723B: Swift/UVOT Upper Limits
  97. GRB 080725: REM prompt observations
  98. Konus-Wind observation of GRB 080723B
  99. GRB 080725: Swift detection of a burst
  100. ATCA radio upper limit on GRB 080723B

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