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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"

18435 results found.

  1. GRB 090831B: Swift detection of a possible burst
  2. GRB 090827: Swift XRT and UVOT observations
  3. GRB 090827 Burst discovered in BAT ground analysis
  4. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  5. GRB 090823: Confirmation of Swift-BAT position by BAT Slew Survey
  6. GRB 090823 Correction to BAT position
  7. GRB 090817: No host galaxy, no supernova
  8. Konus-Wind observations of GRB 090823
  9. GRB 090823 Long burst with IPN triangulation and BAT position
  10. GRB 090817: Swift/UVOT Observations of a Possible Late-Time Brightening
  11. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  12. GRB 090817: Liverpool Telescope Observations
  13. GRB 090817: Confirmation of the X-ray afterglow
  14. GRB 090815C: Swift refined analysis
  15. GRB 090817: Swift/UVOT Upper Limits
  16. GRB 090812: Konus-Wind and Swift/BAT joint spectral analysis
  17. GRB 090817: Swift-XRT observations
  18. GRB 090813: Suzaku WAM observation of the prompt emission
  19. GRB 090812: Suzaku WAM observation of the prompt emission
  20. GRB 090813: CrAO optical obsevations
  21. GRB 090814B: Confirmation of the X-ray afterglow
  22. GRB 090814B: I-band observations from 1.23m CAHA telescope
  23. GRB 090814B: Swift/UVOT Upper Limits
  24. GRB 090814B: Liverpool Telescope Observations
  25. GRB 090814B: Swift-XRT detection of a possible afterglow.
  26. GRB 090814A: Swift/UVOT Observations
  27. GRB 090814A: Swift-XRT Team Refined Analysis
  28. GRB 090814A, RIMOTS optical upper limits
  29. GRB 090814A: Swift-BAT refined analysis
  30. GRB 090814: Enhanced Swift-XRT position
  31. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  32. GRB 090814: Swift detection of a burst
  33. GRB 090813: Fermi GBM observation
  34. GRB 090813: Swift-XRT refined analysis
  35. GRB 090813, Swift-BAT refined analysis
  36. Konus-Wind observations of GRB090813
  37. GRB090813: Swift/UVOT upper limits
  38. GRB 090813: Enhanced Swift-XRT position
  39. GRB 090813: Liverpool Telescope afterglow confirmation
  40. GRB 090813: Swift detection of a burst
  41. GRB 090812: WIRO NIR upper limit
  42. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  43. GRB 090812: RAPTOR detections during the burst
  44. GRB 090812: Swift XRT refined analysis
  45. GRB 090812, RIMOTS optical upper limits
  46. GRB 090812 Swift-BAT Refined Analysis
  47. GRB090812: Swift/UVOT observations
  48. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  49. GRB 090812: Enhanced Swift-XRT position
  50. GRB 090812: Liverpool Telescope afterglow confirmation
  51. GRB 090812: Swift detection of a burst with an optical counterpart
  52. GRB 090809: Swift-XRT refined analysis
  53. GRB090809: Swift/UVOT observations
  54. GRB 090809: Enhanced Swift-XRT position
  55. GRB 090809: Swift-BAT refined analysis
  56. GRB 090809: Swift detection of a burst with a possible optical counterpart
  57. GRB 090807: Liverpool Telescope observations
  58. GRB 090807: Swift/UVOT Upper Limits
  59. GRB 090807: Swift-XRT refined analysis
  60. GRB 090807, Swift-BAT refined analysis
  61. GRB 090807: Enhanced Swift-XRT position
  62. GRB 090807, RIMOTS optical upper limits
  63. GRB 090807: Swift detection of a burst
  64. GRB 090726: optical observation
  65. Swift-BAT trigger 358760 is most likely not a GRB
  66. Swift trigger 358760 is probably a noise event
  67. GRB 090709A : Quick look analysis of the Suzaku observation
  68. GRB 090728: Swift-BAT refined analysis
  69. GRB 090727: GRT Optical Observation
  70. GRB 090728: Swift XRT refined analysis
  71. GRB 090726: GRT Optical Observation
  72. GRB 090727: Swift/UVOT Upper Limits
  73. GRB 090728: Swift/UVOT Upper Limits
  74. GRB 090728: Enhanced Swift-XRT position
  75. GRB 090728, RIMOTS optical upper limits
  76. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  77. GRB 090728: Swift detection of a burst
  78. GRB 090727: Swift-BAT refined analysis
  79. GRB 090727: Swift-XRT refined analysis
  80. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  81. GRB 090727: Enhanced Swift-XRT position
  82. GRB 090727: Liverpool Telescope possible OT candidate
  83. GRB 090727: Swift detection of a burst
  84. GRB090726: Swift/UVOT observations
  85. GRB 090726, Swift-BAT refined analysis
  86. GRB 090726: Afterglow candidate photometryfrom Crni Vrh
  87. GRB 090726: D50 optical observations
  88. GRB 090726: Swift-XRT Team refined analysis
  89. GRB 090726: Enhanced Swift-XRT position
  90. GRB 090726: Swift/UVOT Finding Chart Observation
  91. GRB 090726: Swift-XRT position of probable counterpart
  92. GRB 090726: Swift detection of a burst
  93. Swift Trigger 358354 is not a GRB
  94. GRB 090720: Gemini-North Imaging and Optical Afterglow
  95. Swift XRT and UVOT refned analysis of GRB 090720
  96. GRB 090709A: Swift XRT Timing Analysis
  97. GRB 090715B: VLA radio detection
  98. GRB 090720 Source found in ground processing of Swift-BAT data
  99. GRB 090715A: Suzaku WAM observation of the prompt emission
  100. GRB 090709A - CARMA mm Observations

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