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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"

27018 results found.

  1. GRB 090814C: Fermi GBM detection
  2. GRB 090814A: Swift/UVOT Observations
  3. GRB 090814A: Swift-XRT Team Refined Analysis
  4. GRB 090814A, RIMOTS optical upper limits
  5. GRB 090814A: Swift-BAT refined analysis
  6. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  7. GRB 090814: Swift detection of a burst
  8. GRB 090813: Fermi GBM observation
  9. Fermi Gamma-ray Burst Monitor trigger 271446248 is not a GRB
  10. GRB 090813: Swift-XRT refined analysis
  11. Fermi Gamma-ray Burst Monitor trigger 271833016 is not a GRB
  12. GRB 090813, Swift-BAT refined analysis
  13. Konus-Wind observations of GRB090813
  14. GRB090813: Swift/UVOT upper limits
  15. GRB 090813: Liverpool Telescope afterglow confirmation
  16. GRB 090813: optical candidate from 1.23m CAHA telescope
  17. GRB 090813: Swift detection of a burst
  18. GRB 090812: WIRO NIR upper limit
  19. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  20. GRB 090812: RAPTOR detections during the burst
  21. GRB 090812: Swift XRT refined analysis
  22. GRB 090812, RIMOTS optical upper limits
  23. GRB 090812 Swift-BAT Refined Analysis
  24. GRB090812: Swift/UVOT observations
  25. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  26. GRB 090812: Liverpool Telescope afterglow confirmation
  27. GRB 090812: Swift detection of a burst with an optical counterpart
  28. GRB 090807B: Fermi GBM detection
  29. GRB 090809B: Fermi GBM detection
  30. GRB 090809: Swift-XRT refined analysis
  31. GRB090809: Swift/UVOT observations
  32. GRB 090809: Swift-BAT refined analysis
  33. GRB 090809: Swift detection of a burst with a possible optical counterpart
  34. GRB 090807: Liverpool Telescope observations
  35. GRB 090807: Swift/UVOT Upper Limits
  36. GRB 090807: Swift-XRT refined analysis
  37. GRB 090807, Swift-BAT refined analysis
  38. GRB 090807, RIMOTS optical upper limits
  39. GRB 090807: Swift detection of a burst
  40. Fermi Gamma-ray Burst Monitor trigger 271275771 is not a GRB
  41. GRB 090802B: Fermi GBM detection
  42. GRB 090802: Fermi GBM detection
  43. Swift-BAT trigger 358760 is most likely not a GRB
  44. Swift trigger 358760 is probably a noise event
  45. GRB 090717A: Suzaku WAM observation of the prompt emission
  46. GRB 090709A : Quick look analysis of the Suzaku observation
  47. GRB 090728: Swift-BAT refined analysis
  48. GRB 090727: GRT Optical Observation
  49. GRB 090728: Swift XRT refined analysis
  50. GRB 090727: optical observations
  51. GRB 090726: GRT Optical Observation
  52. GRB 090727: Swift/UVOT Upper Limits
  53. GRB 090728: Swift/UVOT Upper Limits
  54. GRB 090728, RIMOTS optical upper limits
  55. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  56. GRB 090728: Swift detection of a burst
  57. GRB 090727: Swift-BAT refined analysis
  58. GRB 090727: Swift-XRT refined analysis
  59. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  60. GRB 090727: Liverpool Telescope possible OT candidate
  61. GRB 090727: Swift detection of a burst
  62. GRB090726: Swift/UVOT observations
  63. GRB 090726, Swift-BAT refined analysis
  64. GRB 090726: D50 optical observations
  65. GRB 090711: Fermi GBM detection
  66. GRB090726: 6-meter telescope redshift
  67. GRB 090726: Swift-XRT Team refined analysis
  68. GRB 090726: optical transient candidate
  69. GRB 090726: Swift/UVOT Finding Chart Observation
  70. GRB 090726: Swift-XRT position of probable counterpart
  71. GRB 090726: Swift detection of a burst
  72. Swift Trigger 358354 is not a GRB
  73. Konus-Wind and Konus-RF observations of GRB 090719
  74. Konus-RF and Konus-Wind observations of GRB 090718B
  75. Fermi Gamma-ray Burst Monitor triggers 269935914 through 270021937 are not GRBs
  76. Konus-Wind observations of bright hard GRB 090720B
  77. IPN Triangulation of bright GRB 090720B
  78. GRB 090720: Gemini-North Imaging and Optical Afterglow
  79. GRB 090720B: Fermi GBM detection
  80. GRB 090709A: Swift XRT Timing Analysis
  81. GRB 090720 Source found in ground processing of Swift-BAT data
  82. GRB 090717B: Fermi GBM detection
  83. GRB 090717: Fermi GBM detection
  84. GRB 090719: Fermi GBM detection
  85. GRB 090718B: Fermi GBM detection
  86. GRB 090718: Fermi GBM detection
  87. GRB 090720: Fermi GBM detection
  88. GRB 090715A: Suzaku WAM observation of the prompt emission
  89. GRB 090709A - CARMA mm Observations
  90. Konus-Wind observations of short/hard GRB 090715A
  91. GRB 090715B: MASTER optical limit
  92. GRB 090715A: Swift-BAT refined analysis
  93. GRB 090715B: Swift/UVOT followup observations
  94. GRB 090715B: break in the optical afterglow decay
  95. GRB 090715B: Swift XRT Refined Analysis
  96. GRB 090715B: Swift-BAT refined analysis
  97. GRB 090715B - Liverpool Telescope Optical Afterglow Candidate
  98. GRB 090715B: Swift detection of a burst with a possible optical counterpart
  99. GRB 090715A: ROTSE-III Optical Limits
  100. GRB 090715: Swift detection of a short hard burst

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