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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

38608 results found.

  1. GRB 091112: Fermi GBM observation
  2. GRB 091031: Fermi LAT detection of a faint burst
  3. GRB 091112: Swift detection of a possible burst
  4. GRB 091111: BOOTES-3 contemporaneous imaging
  5. GRB 091111: BOOTES-3 observations
  6. GRB 091111: a faint long GRB detected with INTEGRAL
  7. GRB 091109A: GROND and VLT observations
  8. GRB 091109B: Swift/UVOT Upper Limits
  9. GRB 091109B: VLT afterglow confirmation
  10. GRB 091109B: Swift-XRT Team refined analysis
  11. GRB 091109B: VLT observations
  12. GRB 091109b: Magellan Observations
  13. GRB 091109B: Enhanced Swift-XRT position
  14. GRB 091109B: Optical limits from Watcher
  15. GRB 091109B: ROTSE-III Optical Limits
  16. GRB 091109B: Swift detection of a short burst
  17. GRB091109: Correction to GCN 10139
  18. GRB 091030: Fermi GBM detection
  19. GRB 091109: Swift-XRT refined analysis
  20. GRB 091109: BOOTES-3 observations
  21. GRB 091109: Swift/UVOT observations
  22. GRB 091109: Faulkes Telescope South observations
  23. GRB 091109: Enhanced Swift-XRT position
  24. GRB091109: REM detection of the NIR afterglow
  25. GRB 091109: Swift detection of a burst with optical afterglow
  26. GRB 091104: Swift XRT Refined Analysis
  27. GRB 091104: Swift/UVOT Upper Limits
  28. GRB091026 : IRSF NIR upper limit
  29. GRB091102 : MOA optical upper limit
  30. GRB 091104: Enhanced Swift-XRT position
  31. GRB 091104: Swift detection of a burst
  32. GRB 091102: LABOCA/APEX submm observations
  33. Fermi LAT Upper Limits on GRB 091010
  34. GRB 091102 : Faulkes Telescope South Upper Limits
  35. GRB 091102A: Fermi GBM observation
  36. GRB 091102: Swift-XRT refined analysis
  37. GRB 091102: Swift/UVOT Upper Limits
  38. GRB 091102: GROND Upper Limits
  39. GRB 091102: BOOTES-3 observations
  40. GRB 091102: Swift/XRT localization
  41. GRB 091102: ROTSE-III Optical Limits
  42. GRB 091102: Swift/UVOT Finding Chart Observation
  43. GRB 091102: Swift detection of a burst
  44. GRB 091024: optical observations
  45. GRB 091031: Fermi GBM detection
  46. GRB 091024: Fermi LAT upper limits
  47. GRB 090926a, SMARTS optical/IR afterglow observations
  48. GRB 091029, SMARTS optical/IR afterglow observations
  49. GRB 091018, SMARTS optical/IR afterglow observations
  50. GRB091029: Swift/UVOT observations
  51. GRB 091029: Swift XRT refined analysis
  52. Fermi Gamma-ray Burst Monitor trigger 091028818 is not a GRB
  53. GRB 091029: BOOTES-3 observations
  54. GRB 091029: Enhanced Swift-XRT position
  55. GRB091024 optical observations
  56. GRB 091029: Gemini-South Redshift
  57. GRB 091029: GROND Detection of the Optical/NIR Afterglow
  58. GRB 091029: Swift detection of a burst with an optical counterpart
  59. A mistake in testing a new function in Swift
  60. GRB 091020: Fermi GBM observation
  61. GRB 091026: Suzaku WAM observation of the prompt emission
  62. GRB 091024: Keck/LRIS Spectroscopy
  63. GRB 091024: YNAO-GMG observations
  64. GRB 091026: GROND Upper Limits
  65. GRB 091020: Late TLS detection
  66. Radio afterglow detection from GRB 091020
  67. GRB 091026: Swift/UVOT Upper Limits
  68. GRB 091024: Burst was outside the Swift-BAT FOV after T0(BAT)+460sec
  69. GRB 091026: Swift-XRT refined analysis
  70. GRB 091026: Enhanced Swift-XRT position
  71. Konus-Wind and Konus-RF observations of GRB 091024
  72. GRB 091026: Updated Swift-XRT position
  73. GRB 091026: Swift detection of a Gamma Ray Burst
  74. GRB 091020 : Xinglong TNT upper limit
  75. Swift-BAT Triggers 373776-373778 are not real
  76. GRB091024 Swift/UVOT Upper Limits
  77. GRB 091024: TLS Upper Limit
  78. GRB 091024: KAIT optical afterglow observations
  79. Swift-BAT Triggers 373679-373684 are not real
  80. GRB 091024: Fermi GBM Observations
  81. GRB 091024: Swift-XRT team refined analysis
  82. Swift-BAT trigger 373691 is a galactic bulge transient
  83. GRB 091024: Xinglong TNT optical observation
  84. GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
  85. GRB 091024 Gemini-North redshift
  86. GRB 091024: GRAS004 optical observations
  87. GRB 091024: Swift detection of a burst
  88. Konus-Wind observations of GRB 091010
  89. GRB 091020: Swift-XRT refined analysis
  90. GRB 091018: Swift XRT refined analysis
  91. GRB091020 Swift/UVOT observations
  92. GRB 091020: NOT spectroscopic redshift
  93. GRB 091020: MASTER optical transient polarimetry
  94. GRB 091020: Enhanced Swift-XRT position
  95. GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
  96. GRB 091020: Swift detection of a burst with an optical afterglow
  97. GRB 091018: miniTAO/ANIR Observations
  98. Konus-RF observation of GRB 091018
  99. GRB 091018 : Faulkes Telescope South Observations
  100. GRB 091018: VLT/X-shooter spectra

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