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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"

19171 results found.

  1. GRB060218: UV Detection and Light Curves
  2. GRB 060219: Swift/UVOT Upper Limits
  3. GRB 060219: Swift-XRT Team refined analysis
  4. GRB 051221B: Swift-XRT Team Refined Analysis
  5. GRB 060219: Partial refined analysis of the Swift-BAT burst
  6. GRB 060219: Swift-XRT position typo correction
  7. GRB 060219: Swift-XRT position
  8. GRB 060218: optical/nIR observations at La Palma
  9. GRB 060219: Swift-BAT detection of a weak burst
  10. Oddball GRB 060218, transient or GRB?
  11. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  12. Brightening of the Optical Counterpart of the Possible GRB 060218
  13. GRB 060218: MDM Observations
  14. GRB 060218A: ROTSE-III Possible Optical Flare
  15. GRB060218: Swift/XRT refined position of a possible burst
  16. Preliminary refined analysis of the Swift-BAT trigger 191157
  17. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  18. GRB 060211B: Swift/UVOT Upper Limits
  19. GRB 060218: Swift XRT Position
  20. GRB 060218: Swift-BAT detection of a possible burst
  21. GRB 060213: optical afterglow not confirmed
  22. Swift UVOT observations of GRB060213
  23. GRB060213: Swift XRT observations and possible afterglow candidate
  24. GRB 060211b: WIRO NIR Observations
  25. GRB060206: Swift XRT observations of an unbroken powerlaw decay
  26. GRB 060213: IPN localization
  27. GRB 060211a: WIRO NIR Observations
  28. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec
  29. GRB 060211A: Further refined analysis of the Swift burst
  30. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  31. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  32. GRB 050826: Optical Afterglow and Host Galaxy
  33. GRB 060210: Further refined analysis of the Swift-BAT burst
  34. GRB 060211B: Swift/BAT refined analysis
  35. GRB060210: Swift/UVOT Upper Limits
  36. GRB 060211B: Swift-XRT Team refined analysis
  37. GRB060211B: Swift/XRT position
  38. GRB 060210: Optical Observations
  39. GRB 060211A: Swift XRT Team Refined Analysis
  40. GRB 060211B: Swift-BAT detection of a burst
  41. GRB060211: Faulkes North observation
  42. GRB 060211: Swift detection of a long burst
  43. GRB 060210: Refined analysis of the Swift-BAT burst
  44. GRB060210: Swift XRT Refined Analysis
  45. GRB060210: Early Optical Observations
  46. GRB060210:Faulkes Telescope North Afterglow Confirmation
  47. GRB 060210: candidate afterglow
  48. GRB 060210: Swift detection of a burst
  49. GRB060210: Optical afterglow
  50. GRB 060206: Swift/UVOT Observations
  51. Swift-BAT trigger 180931 is not a GRB
  52. GRB060209: RTT150 optical observations
  53. GRB 060209 : TAROT optical observation
  54. GRB 060209(?): Swift-BAT detection of a possible burst
  55. GRB 060206: WSRT Radio Observations
  56. GRB 060203: Swift/UVOT upper limits
  57. GRB060204a: Swift XRT Source is not GRB Afterglow
  58. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  59. GRB 060204A: ROSAT Pointing
  60. GRB060204A: Swift/UVOT observations
  61. GRB 060206: Swift-BAT refined analysis
  62. GRB060206: Swift XRT Refined Analysis
  63. GRB060206: Swift XRT Position
  64. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  65. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  66. GRB060206: Swift-BAT detection of a burst
  67. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  68. BAT GRB 060204C is probably not a GRB
  69. GRB 060204B: BVRi-band detections of optical afterglow
  70. GRB 060204A: Swift XRT upper limit
  71. GRB060204B: Swift/UVOT refined analysis
  72. Swift XRT Observation of GRB 060204C
  73. GRB 060204B: Swift-BAT refined analysis
  74. GRB060204B: Swift XRT Team Refined Analysis
  75. GRB 060204C: OSN limits
  76. GRB 060204C: Liverpool Telescopes optical limit
  77. GRB 060204C: ROTSE-III Optical Limits
  78. GRB 060204C: Swift-BAT detection of a burst
  79. GRB 060124: Radio Observations
  80. GRB060204B: Faulkes OT candidate
  81. GRB060204B, optical observation
  82. GRB060204B - SDSS pre-burst observations
  83. GRB 060203: Swift-BAT refined analysis
  84. GRB 060204B: Swift detection of a burst
  85. GRB 060203: RTT150 optical observations
  86. GRB060203: Swift XRT Team Refined Analysis
  87. GRB060203 - Swift UVOT observation
  88. Swift-BAT trigger is GRB 060203
  89. GRB060203: Observations with SARA
  90. GRB 060203: P60 Confirmation of Optical Afterglow
  91. Possible GRB 060203: candidate optical counterpart
  92. Swift BAT Trigger 180151: Swift XRT source detection
  93. Possible GRB 060203: optical observations at Asiago
  94. Swift-BAT trigger 180151 is unknown origin at this time
  95. GRB 060202: Refined analysis of the Swift-BAT burst
  96. GRB060202, optical observation
  97. GRB 060202: Swift/UVOT upper limits
  98. GRB 060202: Swift XRT Team Refined Analysis
  99. GRB060202: Faulkes North observation
  100. GRB 060202: Swift detection of a burst

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