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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"

24167 results found.

  1. GRB 090831: MAXI GSC detection
  2. GRB 090831B: Swift detection of a possible burst
  3. GRB 090831: Fermi GBM detection
  4. GRB090829: Fermi GBM Detection
  5. GRB 090827: Swift XRT and UVOT observations
  6. GRB 090827 Burst discovered in BAT ground analysis
  7. GRB 090826: Fermi GBM detection
  8. GRB 090828: Fermi GBM detection
  9. Fermi Gamma-ray Burst Monitor trigger 273123112 is not a GRB
  10. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  11. GRB 090823: Confirmation of Swift-BAT position by BAT Slew Survey
  12. GRB 090823 Correction to BAT position
  13. Konus-Wind observations of GRB 090823
  14. GRB 090823 Long burst with IPN triangulation and BAT position
  15. GRB 090817: Swift/UVOT Observations of a Possible Late-Time Brightening
  16. GRB 090820: detection of a strong burst by RT-2 on board CORONAS PHOTON
  17. GRB 090820B: Fermi GBM detection
  18. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  19. GRB 090820: Fermi GBM Detection of a bright burst.
  20. GRB 090815C: Swift refined analysis
  21. GRB 090817: Fermi GBM observation
  22. GRB 090817: Swift/UVOT Upper Limits
  23. GRB 090812: Konus-Wind and Swift/BAT joint spectral analysis
  24. GRB 090813: Suzaku WAM observation of the prompt emission
  25. GRB 090812: Suzaku WAM observation of the prompt emission
  26. GRB 090815B: Fermi GBM detection
  27. GRB 090815: Fermi GBM detection
  28. Fermi Gamma-ray Burst Monitor trigger 271934815 is not a GRB
  29. GRB 090814C: Fermi GBM detection
  30. GRB 090814A: Swift/UVOT Observations
  31. GRB 090814A: Swift-XRT Team Refined Analysis
  32. GRB 090814A, RIMOTS optical upper limits
  33. GRB 090814A: Swift-BAT refined analysis
  34. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  35. GRB 090814: Swift detection of a burst
  36. GRB 090813: Fermi GBM observation
  37. Fermi Gamma-ray Burst Monitor trigger 271446248 is not a GRB
  38. GRB 090813: Swift-XRT refined analysis
  39. Fermi Gamma-ray Burst Monitor trigger 271833016 is not a GRB
  40. GRB 090813, Swift-BAT refined analysis
  41. Konus-Wind observations of GRB090813
  42. GRB090813: Swift/UVOT upper limits
  43. GRB 090813: Liverpool Telescope afterglow confirmation
  44. GRB 090813: optical candidate from 1.23m CAHA telescope
  45. GRB 090813: Swift detection of a burst
  46. GRB 090812: WIRO NIR upper limit
  47. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  48. GRB 090812: RAPTOR detections during the burst
  49. GRB 090812: Swift XRT refined analysis
  50. GRB 090812, RIMOTS optical upper limits
  51. GRB 090812 Swift-BAT Refined Analysis
  52. GRB090812: Swift/UVOT observations
  53. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  54. GRB 090812: Liverpool Telescope afterglow confirmation
  55. GRB 090812: Swift detection of a burst with an optical counterpart
  56. GRB 090807B: Fermi GBM detection
  57. GRB 090621B: MAGIC telescope GeV observation
  58. GRB 090621A: MAGIC telescope GeV observation
  59. GRB 090809B: Fermi GBM detection
  60. GRB 090809: Swift-XRT refined analysis
  61. GRB090809: Swift/UVOT observations
  62. GRB 090809: Swift-BAT refined analysis
  63. GRB 090809: Swift detection of a burst with a possible optical counterpart
  64. GRB 090807: Liverpool Telescope observations
  65. GRB 090807: Swift/UVOT Upper Limits
  66. GRB 090807: Swift-XRT refined analysis
  67. GRB 090807, Swift-BAT refined analysis
  68. GRB 090807, RIMOTS optical upper limits
  69. GRB 090807: Swift detection of a burst
  70. Fermi Gamma-ray Burst Monitor trigger 271275771 is not a GRB
  71. GRB 090802B: Fermi GBM detection
  72. GRB 090802: Fermi GBM detection
  73. Swift-BAT trigger 358760 is most likely not a GRB
  74. Swift trigger 358760 is probably a noise event
  75. GRB 090717A: Suzaku WAM observation of the prompt emission
  76. GRB 090709A : Quick look analysis of the Suzaku observation
  77. GRB 090728: Swift-BAT refined analysis
  78. GRB 090727: GRT Optical Observation
  79. GRB 090728: Swift XRT refined analysis
  80. GRB 090727: optical observations
  81. GRB 090726: GRT Optical Observation
  82. GRB 090727: Swift/UVOT Upper Limits
  83. GRB 090728: Swift/UVOT Upper Limits
  84. GRB 090728, RIMOTS optical upper limits
  85. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  86. GRB 090728: Swift detection of a burst
  87. GRB 090727: Swift-BAT refined analysis
  88. GRB 090727: Swift-XRT refined analysis
  89. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  90. GRB 090727: Liverpool Telescope possible OT candidate
  91. GRB 090727: Swift detection of a burst
  92. GRB090726: Swift/UVOT observations
  93. GRB 090726, Swift-BAT refined analysis
  94. GRB 090726: D50 optical observations
  95. GRB 090711: Fermi GBM detection
  96. GRB090726: 6-meter telescope redshift
  97. GRB 090726: Swift-XRT Team refined analysis
  98. GRB 090726: optical transient candidate
  99. GRB 090726: Swift/UVOT Finding Chart Observation
  100. GRB 090726: Swift-XRT position of probable counterpart

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