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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"

5819 results found.

  1. GRB060213: MASTER final result
  2. GRB060213:_MASTER_optical_observation
  3. GRB 060213: IPN localization
  4. GRB060121: optical observations
  5. GRB 060211: ROTSE-III Optical Limits
  6. GRB 060211: Swift detection of a long burst
  7. GRB060210: Swift XRT Refined Analysis
  8. GRB 060210: Swift detection of a burst
  9. Swift-BAT trigger 180931 is not a GRB
  10. GRB060209: RTT150 optical observations
  11. GRB 060209 : TAROT optical observation
  12. GRB060209A: MASTER optical observation
  13. GRB 060206: TTT Observations
  14. GRB 060206: Super-LOTIS observations
  15. GRB060204C: optical observation
  16. GRB060204B, optical observation
  17. GRB 060202: GETS observation
  18. GRB060202, optical observation
  19. GRB 060202: Swift/UVOT upper limits
  20. GRB 060121: Gemini Late-time Observations
  21. GRB 060130, SMARTS optical observations
  22. GRB 060130: FRAM optical observations
  23. GRB060124: detailed XRT analysis
  24. GRB 060116: MARGE optical observations
  25. GRB 060121: candidate optical counterpart
  26. GRB060121 - SDSS pre-burst observations
  27. GRB 060116: IR Candidate Afterglow
  28. GRB 060116: Swift-BAT detection of a burst
  29. GRB 060115: Swift/UVOT upper limits
  30. GRB 060115: Swift detection of a burst
  31. GRB060108: Faulkes North afterglow evidence
  32. GRB 060110: MARGE observations
  33. GRB 060111B: Swift detection of a burst
  34. GRB060110, optical observation
  35. GRB 060109: Swift/UVOT upper limits
  36. GRB060109, optical observation
  37. GRB 060109: Swift Detection of a long burst
  38. GRB060108: SDSS pre-burst observations
  39. GRB 060105: Mitsume optical observations
  40. GRB060105, optical observation
  41. GRB060105 : Kiso optical observation
  42. GRB051211B: optical observations
  43. GRB 051221B: ROTSE-III Optical Limits
  44. Refined analysis of the SWIFT J1626.6-5156
  45. Swift detection of an RS CVn flare star
  46. GRB051105: optical observations
  47. Possible resuming of the SGR 1806-20 activity
  48. GRB051117A : XRT refined analysis
  49. GRB 051117B: Swift detection of a burst
  50. GRB 051109B : Nainital upper limits
  51. GRB 051114: Swift-BAT refined analysis
  52. GRB 051114: Swift-BAT detection of a short burst
  53. GRB 051105a: GETS optical limit
  54. GRB 051109b: GETS observation
  55. GRB 051109A: KAIT optical observations
  56. GRB 051109A: Swift-UVOT Observations
  57. GRB 051109B Kiso optical follow-up observation
  58. GRB 051109a: IR Photometry and Astrometry
  59. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  60. GRB 051109a: IR Detections
  61. GRB051103: MASTER: OT limit and host galaxy candidates
  62. GRB051103:_MASTER_optical_observations
  63. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  64. GRB 051105: Optical limit
  65. GRB051028:MASTER observations
  66. GRB051021a: optical observations
  67. GRB051021A: Swift XRT refined analysis
  68. GRB051022,optical observation
  69. GRB 051022: Optical observations
  70. GRB 051021B: Swift detection of a burst
  71. GRB051021: Swift XRT analysis
  72. GRB 051016B: Swift detection of a soft burst
  73. GRB051006: optical observations
  74. GRB050805A: Rc optical observations
  75. GRB 051006: XRT refined analysis
  76. GRB 051006: optical observations at Sierra Nevada
  77. GRB 051006: XRT position
  78. GRB/SGR 050925: IR Observations
  79. GRB050922C - Swift UVOT preliminary analysis
  80. GRB050925: Swift UVOT upper limits
  81. GRB050925: Swift-BAT detection of a short burst
  82. GRB050922C: Optical Observations
  83. GRB 050922C: Swift XRT refined analysis
  84. GRB 050922C: Swift-BAT refined analysis
  85. GRB 050922B: Swift-BAT refined analysis
  86. GRB 050922C: NOT optical observations
  87. GRB 050922C: Swift detection of a bright burst
  88. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  89. GRB050916: Swift/UVOT Upper Limits
  90. GRB 050916: XRT position
  91. GRB 050915b, SMARTS optical/IR observations of the XRT position
  92. GRB 050915a: IR Transient
  93. GRB 050915b, SMARTS optical/IR observations
  94. GRB 050915: IR Observations
  95. GRB 050915: Swift detection of a GRB
  96. GRB 050910a: TAROT early optical limits
  97. GRB 050908: Optical observations
  98. GRB050904: Optical Observations
  99. GRB 050904: TAROT optical limits
  100. GRB 050827: P200 NIR Observations

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