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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"

19594 results found.

  1. GRB 090813: Liverpool Telescope afterglow confirmation
  2. GRB 090813: Swift detection of a burst
  3. GRB 090812: WIRO NIR upper limit
  4. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  5. GRB 090812: RAPTOR detections during the burst
  6. GRB 090812: Swift XRT refined analysis
  7. GRB 090812, RIMOTS optical upper limits
  8. GRB 090812 Swift-BAT Refined Analysis
  9. GRB090812: Swift/UVOT observations
  10. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  11. GRB 090812: Enhanced Swift-XRT position
  12. GRB 090812: Liverpool Telescope afterglow confirmation
  13. GRB 090812: Swift detection of a burst with an optical counterpart
  14. GRB 090809: Swift-XRT refined analysis
  15. GRB090809: Swift/UVOT observations
  16. GRB 090809: Enhanced Swift-XRT position
  17. GRB 090809: Swift-BAT refined analysis
  18. GRB 090809: Swift detection of a burst with a possible optical counterpart
  19. GRB 090807: Liverpool Telescope observations
  20. GRB 090807: Swift/UVOT Upper Limits
  21. GRB 090807: Swift-XRT refined analysis
  22. GRB 090807, Swift-BAT refined analysis
  23. GRB 090807: Enhanced Swift-XRT position
  24. GRB 090807, RIMOTS optical upper limits
  25. GRB 090807: Swift detection of a burst
  26. GRB 090726: optical observation
  27. Swift-BAT trigger 358760 is most likely not a GRB
  28. Swift trigger 358760 is probably a noise event
  29. GRB 090709A : Quick look analysis of the Suzaku observation
  30. GRB 090728: Swift-BAT refined analysis
  31. GRB 090727: GRT Optical Observation
  32. GRB 090728: Swift XRT refined analysis
  33. GRB 090726: GRT Optical Observation
  34. GRB 090727: Swift/UVOT Upper Limits
  35. GRB 090728: Swift/UVOT Upper Limits
  36. GRB 090728: Enhanced Swift-XRT position
  37. GRB 090728, RIMOTS optical upper limits
  38. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  39. GRB 090728: Swift detection of a burst
  40. GRB 090727: Swift-BAT refined analysis
  41. GRB 090727: Swift-XRT refined analysis
  42. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  43. GRB 090727: Enhanced Swift-XRT position
  44. GRB 090727: Liverpool Telescope possible OT candidate
  45. GRB 090727: Swift detection of a burst
  46. GRB090726: Swift/UVOT observations
  47. GRB 090726, Swift-BAT refined analysis
  48. GRB 090726: Afterglow candidate photometryfrom Crni Vrh
  49. GRB 090726: D50 optical observations
  50. GRB 090726: Swift-XRT Team refined analysis
  51. GRB 090726: Enhanced Swift-XRT position
  52. GRB 090726: Swift/UVOT Finding Chart Observation
  53. GRB 090726: Swift-XRT position of probable counterpart
  54. GRB 090726: Swift detection of a burst
  55. Swift Trigger 358354 is not a GRB
  56. GRB 090720: Gemini-North Imaging and Optical Afterglow
  57. Swift XRT and UVOT refned analysis of GRB 090720
  58. GRB 090709A: Swift XRT Timing Analysis
  59. GRB 090715B: VLA radio detection
  60. GRB 090720 Source found in ground processing of Swift-BAT data
  61. GRB 090715A: Suzaku WAM observation of the prompt emission
  62. GRB 090709A - CARMA mm Observations
  63. Konus-Wind observations of short/hard GRB 090715A
  64. GRB 090715B: MASTER optical limit
  65. GRB 090715A: Swift-BAT refined analysis
  66. GRB 090715B: Swift/UVOT followup observations
  67. GRB 090715B: break in the optical afterglow decay
  68. GRB 090715B: Enhanced Swift-XRT position
  69. GRB 090715B: Swift XRT Refined Analysis
  70. GRB 090715B: Swift-BAT refined analysis
  71. GRB 090715B - Liverpool Telescope Optical Afterglow Candidate
  72. Swift problem fixed
  73. GRB 090715B: Swift detection of a burst with a possible optical counterpart
  74. GRB 090715A: ROTSE-III Optical Limits
  75. GRB 090715: Swift detection of a short hard burst
  76. Swift satellite anomaly
  77. GRB 090712: Fermi GBM observation
  78. GRB 090712: Swift-BAT refined analysis
  79. GRB 090712: Swift detection of a burst
  80. GRB 090621B: MTM-500 optical observations
  81. GRB 090709A: deep optical observation with the 10.4m GTC
  82. GRB 090709A: Suzaku WAM observation of the prompt emission
  83. GRB 090709A: Swift UVOT upper limits
  84. GRB 090709B: Fermi GBM detection
  85. GRB 090709A: confirmation of the periodicity in the SPI-ACS data
  86. GRB 090709A: evidence for a very red afterglow at low z
  87. GRB 090709A: RAPTOR Limits During Gamma-Ray Emission
  88. GRB 090709A: Swift XRT Refined Analysis
  89. GRB 090709B, Swift-BAT refined analysis
  90. GRB 090709A: Swift-BAT refined analysis
  91. GRB090709A: High Energy BAT/XRT Analysis Suggests Low to Moderate Redshift
  92. GRB 090709A: Wyoming Infrared Observatory NIR upper limits
  93. GRB 090709A, RIMOTS optical upper limits
  94. GRB 090709A: Enhanced Swift-XRT position
  95. GRB 090709B: Swift detection of a burst
  96. GRB 090708 : Fermi GBM detection
  97. GRB 090709: Faulkes Telescope North Upper Limits
  98. GRB 090709: PAIRITEL NIR Upper Limits
  99. GRB 090709: ROTSE-III Optical Limits
  100. GRB 090709: Swift detection of a bright burst

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