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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"

18432 results found.

  1. GRB 100526A: Swift/UVOT Upper Limits
  2. GRB 100526A: Swift XRT refined analysis
  3. GRB 100526B: Swift-BAT refined analysis
  4. GRB 100526B: Swift XRT/UVOT observations
  5. GRB 100526A: Swift-BAT refined analysis
  6. GRB 100526A: Enhanced Swift-XRT position
  7. GRB 100526B: Swift detection of a probable GRB
  8. GRB 100526A: MASTER-Net optical alert observations
  9. GRB 100526A: Swift detection of a burst
  10. Konus-Wind observation of GRB 100522A
  11. GRB100522A: Suzaku WAM observation of the prompt emission
  12. GRB 100522A: GROND observations, upper limits
  13. Swift/UVOT observations of GRB100522A.
  14. GRB 100522A: Fermi GBM observation
  15. GRB 100522A: Swift XRT refined analysis
  16. GRB 100522A, Swift-BAT refined analysis
  17. GRB 100522A: Enhanced Swift-XRT position
  18. GRB 100522A: BOOTES-2 optical limit
  19. GRB 100522A: Swift detection of a burst
  20. GRB 100418A: CrAO optical observations
  21. GRB 100518A: Swift/UVOT Upper Limits
  22. GRB 100518A: Swift-XRT refined analysis
  23. GRB 100518A: Swift target of opportunity observation of the INTEGRAL burst
  24. Swift-BAT trigger 422437 is not anything astrophysical
  25. Swift Trigger 422437 is probably not a GRB
  26. GRB 100514A: optical afterglow confirmation
  27. GRB 100514A: Swift/UVOT Observations
  28. GRB 100514A: Swift XRT refined analysis
  29. GRB 100514A: MASTER-Net optical observations
  30. GRB 100514A: Enhanced Swift-XRT position
  31. GRB 100514A: Swift-BAT refined analysis
  32. GRB 100514A: Faulkes Telescope South observations
  33. GRB 100514A: Swift detection of a burst
  34. GRB 100513A: Faulkes Telescope South observations
  35. GRB 100513A: Swift/UVOT upper limits
  36. GRB 100513A, RIMOTS optical upper limits
  37. GRB 100513A: Swift XRT refined analysis
  38. GRB 100513A: Swift-BAT refined analysis
  39. GRB 100513A: Enhanced Swift-XRT position
  40. GRB 100513A: PAIRITEL NIR afterglow candidate
  41. GRB 100513A: Swift detection of a burst
  42. GRB 100511A: Super-LOTIS early observations
  43. Swift-BAT trigger 421695 is likely not astrophysical
  44. GRB 100511A, RIMOTS optical upper limits
  45. Trigger 421695: Swift detection of a possible burst
  46. GRB100508A: Further Swift/UVOT Observations
  47. GRB 100508A: GROND Detection of the optical afterglow
  48. GRB 100508A: Swift-XRT Refined analysis
  49. GRB 100508A: Swift-BAT refined analysis
  50. GRB 100508A: Enhanced Swift-XRT position
  51. GRB100508A: Swift/UVOT Detection of the Afterglow
  52. GRB 100508A: ROTSE-III Optical Limits
  53. GRB 100508A: Swift detection of a burst
  54. Swift-BAT refined analysis of trigger 421262
  55. GRB 100504A: Fermi GBM observation
  56. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  57. GRB 100504A: Swift/UVOT Observations
  58. GRB 100418A: Flattening of the Swift/UVOT Optical Light Curve
  59. GRB 100504A: Swift-XRT refined analysis
  60. GRB 100504A: Enhanced Swift-XRT position
  61. GRB 100504A: GROND Upper limits
  62. GRB 100504A: Swift-BAT refined analysis
  63. GRB 100504A: UVOT-enhanced XRT position
  64. GRB 100504A: Swift detection of a burst
  65. Swift-BAT trigger 421072 is not astrophyical
  66. INTEGRAL observations of Swift GRB trigger 421072
  67. GRB100423A : Suzaku WAM observation of the prompt emission
  68. Trigger 421072: Possible Swift detection of a GRB or transient
  69. GRB 100420A: Terskol optical upper limit
  70. GRB 100427A: Swift XRT and UVOT Upper Limits
  71. GRB 100427A: Fermi GBM detection
  72. GRB 100427A detected in ground analysis of Swift BAT data
  73. Konus-Wind observation of GRB 100423A
  74. GRB 100423A: CrAO optical observations
  75. GRB 100418A: Terskol optical observations
  76. GRB 100424A: CrAO optical observations
  77. GRB 100425A: Swift XRT refined analysis
  78. GRB100425A: Swift/UVOT Upper Limits
  79. GRB 100424A: Swift/UVOT Upper Limits
  80. GRB 100425A: Enhanced Swift-XRT position
  81. GRB 100425A: Swift-BAT refined analysis
  82. GRB 100425A: GROND afterglow observation
  83. GRB 100424A: D50 optical limits
  84. GRB 100424A : Lulin early z'-band upper limit
  85. GRB 100424A: GROND Upper Limits
  86. GRB 100424A: PAIRITEL NIR Upper Limits
  87. GRB 100424A: Swift-XRT refined analysis
  88. GRB 100425A: Swift detection of a burst
  89. GRB 100424A, Swift-BAT refined analysis
  90. GRB 100424A: Enhanced Swift-XRT position
  91. GRB 100424A: Prompt enhanced Swift-XRT position.
  92. GRB 100424A: Swift detection of a burst
  93. GRB 100420A: GRT Optical Observation
  94. Swift-BAT refined analysis of trigger 420256
  95. Swift Trigger 420256: D50 optical limits
  96. GRB 100418A: Possible Evidence for a Supernova
  97. GRB 100420A: Swift-BAT refined analysis
  98. GRB 100423A: Swift-BAT refined analysis
  99. Swift Trigger 420256: IAC80 R-band observations
  100. Swift Trigger 420256: BOOTES-2 observations

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