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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"

27404 results found.

  1. GRB 090916, Swift-BAT refined analysis
  2. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  3. GRB 090915 Swift-BAT detection of a burst in ground analysis
  4. GRB 090827: Confirmation of the X-ray afterglow
  5. GRB 090912: Swift-XRT refined analysis
  6. GRB 090912, Swift-BAT refined analysis
  7. GRB 090912: Swift/UVOT Upper Limits
  8. GRB 090912 optical upper limit
  9. GRB 090912: Enhanced Swift-XRT position
  10. GRB 090912: Swift detection of a burst
  11. GRB 090910: Fermi GBM detection
  12. GRB 090814A: Skynet/DSO & GORT Observations
  13. GRB 090823: Swift XRT confirmation of the X-ray afterglow
  14. GRB 090904B: GROND detection of the optical afterglow
  15. GRB 090831A: Suzaku WAM observation of the prompt emission
  16. GRB 090904B: Swift/UVOT Refined Analysis
  17. GRB 090902B: Suzaku WAM observation of the prompt emission
  18. GRB 090829A: Suzaku WAM observation of the prompt emission
  19. GRB 090904B: Fermi GBM detection
  20. GRB 090904A: Swift-XRT refined analysis
  21. GRB 090904B: Swift XRT Refined Analysis
  22. GRB 090904B: Swift-BAT refined analysis
  23. GRB 090902B: VLA radio detection
  24. GRB 090904A: Swift-BAT refined analysis
  25. GRB 090904B: Enhanced Swift-XRT position
  26. GRB 090904A: Enhanced Swift-XRT position
  27. GRB 090904A: NOT observations
  28. GRB090904B: REM observations
  29. GRB 090904B: Swift detection of a burst
  30. GRB 090904: Swift detection of a burst
  31. GRB 090902B: Swift/UVOT refined analysis
  32. GRB090902B: Swift XRT refined analysis
  33. GRB 090902B: Faulkes Telescope North observations
  34. GRB 090902B: GROND NIR Afterglow Observations
  35. GRB 090902B: Enhanced Swift-XRT position
  36. GRB 090902B: Optical afterglow candidate
  37. GRB090902B: Swift/UVOT observations
  38. GRB 090902B: Swift/XRT Afterglow Candidate
  39. GRB 090902B: Fermi LAT detection
  40. GRB 090902B: Fermi GBM detection of a bright burst
  41. GRB 090902: Fermi GBM detection
  42. GRB 090831A: IPN Triangulation
  43. GRB 090831C BAT refined analysis
  44. GRB 090831C: GROND upper limits
  45. Swift Trigger 361477, called GRB090831B, is probably not real.
  46. GRB090831C: Swift/UVOT upper limits
  47. GRB 090831B: MITSuME optical upper limits
  48. GRB 090831C: Swift XRT Refined Analysis
  49. GRB 090829B: Fermi GBM Detection
  50. GRB 090831C: Enhanced Swift-XRT position
  51. GRB 090831C: Swift detection of a burst
  52. GRB 090831B, RIMOTS optical upper limits
  53. GRB 090831: MAXI GSC detection
  54. GRB 090831B: Swift detection of a possible burst
  55. GRB 090831: Fermi GBM detection
  56. GRB090829: Fermi GBM Detection
  57. GRB 090827: Swift XRT and UVOT observations
  58. GRB 090827 Burst discovered in BAT ground analysis
  59. GRB 090826: Fermi GBM detection
  60. GRB 090828: Fermi GBM detection
  61. GRB 090817 - TLS Observations
  62. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  63. GRB 090823 Long burst with IPN triangulation and BAT position
  64. GRB 090820B: Fermi GBM detection
  65. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  66. GRB 090820: MASTER-Net optical polarization observations
  67. GRB 090820: Fermi GBM Detection of a bright burst.
  68. GRB 090817: optical upper limit
  69. GRB 090817: Confirmation of the X-ray afterglow
  70. GRB 090815C: Swift refined analysis
  71. GRB 090817: Fermi GBM observation
  72. GRB 090817: Swift/UVOT Upper Limits
  73. GRB 090812: Konus-Wind and Swift/BAT joint spectral analysis
  74. GRB 090817: Swift-XRT observations
  75. GRB 090814A: optical observations
  76. GRB 090813: Suzaku WAM observation of the prompt emission
  77. GRB 090812: Suzaku WAM observation of the prompt emission
  78. VLA radio non-detection of GRB 090812
  79. GRB 090815B: Fermi GBM detection
  80. GRB 090815: Fermi GBM detection
  81. GRB 090813: CrAO optical obsevations
  82. GRB090814A: NOT optical follow-ups
  83. GRB 090814B: Swift/UVOT Upper Limits
  84. GRB 090814B: Liverpool Telescope Observations
  85. GRB 090814C: Fermi GBM detection
  86. GRB 090814B: Swift-XRT detection of a possible afterglow.
  87. GRB 090814A: Swift/UVOT Observations
  88. GRB 090814A: Swift-XRT Team Refined Analysis
  89. GRB 090814A, RIMOTS optical upper limits
  90. GRB 090814A: Swift-BAT refined analysis
  91. GRB090814A: VLT spectroscopy
  92. GRB 090814: Enhanced Swift-XRT position
  93. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  94. GRB 090814: Swift detection of a burst
  95. GRB 090813: Swift-XRT refined analysis
  96. GRB 090813, Swift-BAT refined analysis
  97. Konus-Wind observations of GRB090813
  98. GRB090813: Swift/UVOT upper limits
  99. GRB 090813: Enhanced Swift-XRT position
  100. GRB 090813: Liverpool Telescope afterglow confirmation

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