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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"

18476 results found.

  1. GRB 060223: Swift detection of a burst
  2. GRB 060219: Swift-BAT refined analysis
  3. GRB 060218: Further refined analysis of the Swift-BAT burst
  4. GRB 060218: Likely an underluminous GRB
  5. GRB 060219: SDSS galaxy inside XRT error circle
  6. GRB060218: UV Detection and Light Curves
  7. GRB 060219: Swift/UVOT Upper Limits
  8. GRB 060219: Swift-XRT Team refined analysis
  9. GRB 051221B: Swift-XRT Team Refined Analysis
  10. GRB 060219: Partial refined analysis of the Swift-BAT burst
  11. GRB 060219: Swift-XRT position typo correction
  12. GRB 060219: Swift-XRT position
  13. GRB 060218: optical/nIR observations at La Palma
  14. GRB 060219: Swift-BAT detection of a weak burst
  15. Oddball GRB 060218, transient or GRB?
  16. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  17. Brightening of the Optical Counterpart of the Possible GRB 060218
  18. GRB 060218: MDM Observations
  19. GRB 060218A: ROTSE-III Possible Optical Flare
  20. GRB060218: Swift/XRT refined position of a possible burst
  21. Preliminary refined analysis of the Swift-BAT trigger 191157
  22. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  23. GRB 060211B: Swift/UVOT Upper Limits
  24. GRB 060218: Swift XRT Position
  25. GRB 060218: Swift-BAT detection of a possible burst
  26. GRB 060213: optical afterglow not confirmed
  27. Swift UVOT observations of GRB060213
  28. GRB060213: Swift XRT observations and possible afterglow candidate
  29. GRB 060211b: WIRO NIR Observations
  30. GRB060206: Swift XRT observations of an unbroken powerlaw decay
  31. GRB 060213: IPN localization
  32. GRB 060211a: WIRO NIR Observations
  33. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec
  34. GRB 060211A: Further refined analysis of the Swift burst
  35. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  36. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  37. GRB 050826: Optical Afterglow and Host Galaxy
  38. GRB 060210: Further refined analysis of the Swift-BAT burst
  39. GRB 060211B: Swift/BAT refined analysis
  40. GRB060210: Swift/UVOT Upper Limits
  41. GRB 060211B: Swift-XRT Team refined analysis
  42. GRB060211B: Swift/XRT position
  43. GRB 060210: Optical Observations
  44. GRB 060211A: Swift XRT Team Refined Analysis
  45. GRB 060211B: Swift-BAT detection of a burst
  46. GRB060211: Faulkes North observation
  47. GRB 060211: Swift detection of a long burst
  48. GRB 060210: Refined analysis of the Swift-BAT burst
  49. GRB060210: Swift XRT Refined Analysis
  50. GRB060210: Early Optical Observations
  51. GRB060210:Faulkes Telescope North Afterglow Confirmation
  52. GRB 060210: candidate afterglow
  53. GRB 060210: Swift detection of a burst
  54. GRB060210: Optical afterglow
  55. GRB 060206: Swift/UVOT Observations
  56. Swift-BAT trigger 180931 is not a GRB
  57. GRB060209: RTT150 optical observations
  58. GRB 060209 : TAROT optical observation
  59. GRB 060209(?): Swift-BAT detection of a possible burst
  60. GRB 060206: WSRT Radio Observations
  61. GRB 060203: Swift/UVOT upper limits
  62. GRB060204a: Swift XRT Source is not GRB Afterglow
  63. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  64. GRB 060204A: ROSAT Pointing
  65. GRB060204A: Swift/UVOT observations
  66. GRB 060206: Swift-BAT refined analysis
  67. GRB060206: Swift XRT Refined Analysis
  68. GRB060206: Swift XRT Position
  69. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  70. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  71. GRB060206: Swift-BAT detection of a burst
  72. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  73. BAT GRB 060204C is probably not a GRB
  74. GRB 060204B: BVRi-band detections of optical afterglow
  75. GRB 060204A: Swift XRT upper limit
  76. GRB060204B: Swift/UVOT refined analysis
  77. Swift XRT Observation of GRB 060204C
  78. GRB 060204B: Swift-BAT refined analysis
  79. GRB060204B: Swift XRT Team Refined Analysis
  80. GRB 060204C: OSN limits
  81. GRB 060204C: Liverpool Telescopes optical limit
  82. GRB 060204C: ROTSE-III Optical Limits
  83. GRB 060204C: Swift-BAT detection of a burst
  84. GRB 060124: Radio Observations
  85. GRB060204B: Faulkes OT candidate
  86. GRB060204B, optical observation
  87. GRB060204B - SDSS pre-burst observations
  88. GRB 060203: Swift-BAT refined analysis
  89. GRB 060204B: Swift detection of a burst
  90. GRB 060203: RTT150 optical observations
  91. GRB060203: Swift XRT Team Refined Analysis
  92. GRB060203 - Swift UVOT observation
  93. Swift-BAT trigger is GRB 060203
  94. GRB060203: Observations with SARA
  95. GRB 060203: P60 Confirmation of Optical Afterglow
  96. Possible GRB 060203: candidate optical counterpart
  97. Swift BAT Trigger 180151: Swift XRT source detection
  98. Possible GRB 060203: optical observations at Asiago
  99. Swift-BAT trigger 180151 is unknown origin at this time
  100. GRB 060202: Refined analysis of the Swift-BAT burst

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