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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"

27039 results found.

  1. Swift detection of outburst from the SFXT IGR J18410-0535
  2. GRB 100528A: GROND detection in all bands
  3. GRB100526B: GROND Upper limits
  4. GRB 100528A: Fermi GBM observation
  5. GRB 100526B: Swift-XRT confirmation of fading afterglow
  6. GRB 100526B: Swift/UVOT Upper Limits
  7. GRB 100526A: Swift/UVOT Upper Limits
  8. GRB 100526A: Swift XRT refined analysis
  9. GRB 100526B: Swift-BAT refined analysis
  10. GRB 100526B: Swift XRT/UVOT observations
  11. GRB 100526A: Swift-BAT refined analysis
  12. GRB 100526B: Swift detection of a probable GRB
  13. GRB 100526A: Swift detection of a burst
  14. Konus-Wind observation of GRB 100522A
  15. GRB100522A: Suzaku WAM observation of the prompt emission
  16. GRB 100418A: Subaru late-time optical imaging and spectroscopy
  17. Swift/UVOT observations of GRB100522A.
  18. GRB 100522A: Fermi GBM observation
  19. GRB 100522A: Swift XRT refined analysis
  20. GRB 100522A, Swift-BAT refined analysis
  21. GRB 100522A: BOOTES-2 optical limit
  22. GRB 100522A: Swift detection of a burst
  23. GRB 100518A: GROND afterglow observation and photo-z
  24. GRB 100518A: Swift/UVOT Upper Limits
  25. GRB 100518A: Swift-XRT refined analysis
  26. GRB 100518A: optical afterglow decay
  27. Update to the configuration of the Fermi-LAT onboard GRB search
  28. GRB 100518A: Swift target of opportunity observation of the INTEGRAL burst
  29. Swift-BAT trigger 422437 is not anything astrophysical
  30. Swift Trigger 422437 is probably not a GRB
  31. Fermi/GBM trigger 295791986 - unreliable location
  32. GRB 100517A: MASTER-Net wide field camera prompt optical observations
  33. GRB 100514A: Swift/UVOT Observations
  34. GRB 100514A: YNAO-GMG observations
  35. GRB 100514A: Swift XRT refined analysis
  36. GRB 100514A: Swift-BAT refined analysis
  37. GRB 100514A: Faulkes Telescope South observations
  38. GRB 100514A: Swift detection of a burst
  39. GRB 100513A: Faulkes Telescope South observations
  40. GRB 100513A: Swift/UVOT upper limits
  41. GRB 100513A, RIMOTS optical upper limits
  42. GRB 100513A: Swift-BAT refined analysis
  43. GRB 100513A: PAIRITEL NIR afterglow candidate
  44. GRB 100513A: Swift detection of a burst
  45. GRB 100510A: Fermi GBM detection/observation
  46. GRB 100511A: Fermi GBM detection/observation
  47. GRB 100511A: Super-LOTIS early observations
  48. Swift-BAT trigger 421695 is likely not astrophysical
  49. GRB 100510A: MAXI/GSC detection
  50. GRB 100511A, RIMOTS optical upper limits
  51. Trigger 421695: Swift detection of a possible burst
  52. GRB100508A: Further Swift/UVOT Observations
  53. GRB100503A: Suzaku WAM observation of the prompt emission
  54. GRB 100508A: GROND Detection of the optical afterglow
  55. GRB 100508A: Swift-XRT Refined analysis
  56. GRB 100508A: Swift-BAT refined analysis
  57. GRB100508A: Swift/UVOT Detection of the Afterglow
  58. GRB 100508A: ROTSE-III Optical Limits
  59. GRB 100508A: Swift detection of a burst
  60. Fermi Gamma-ray Burst Monitor trigger 294712621 is not a GRB
  61. Swift-BAT refined analysis of trigger 421262
  62. GRB 100504A: Fermi GBM observation
  63. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  64. GRB 100504A: Swift/UVOT Observations
  65. GRB 100418A: Flattening of the Swift/UVOT Optical Light Curve
  66. GRB 100504A: GROND Upper limits
  67. GRB 100504A: Swift-BAT refined analysis
  68. GRB 100504A: SARA-South Upper Limit
  69. GRB 100503A: Fermi GBM detection
  70. GRB 100504A: UVOT-enhanced XRT position
  71. GRB 100504A: Swift detection of a burst
  72. Swift-BAT trigger 421072 is not astrophyical
  73. INTEGRAL observations of Swift GRB trigger 421072
  74. GRB100423A : Suzaku WAM observation of the prompt emission
  75. Trigger 421072: Possible Swift detection of a GRB or transient
  76. GRB 100427A: Fermi GBM detection
  77. GRB 100427A detected in ground analysis of Swift BAT data
  78. Konus-Wind observation of GRB 100423A
  79. GRB 100425A: Swift XRT refined analysis
  80. GRB100425A: Swift/UVOT Upper Limits
  81. GRB 100424A: Swift/UVOT Upper Limits
  82. GRB 100425A: Swift-BAT refined analysis
  83. GRB 100425A: GROND afterglow observation
  84. GRB 100424A: D50 optical limits
  85. GRB 100424A : Lulin early z'-band upper limit
  86. GRB 100424A: GROND Upper Limits
  87. GRB 100424A: PAIRITEL NIR Upper Limits
  88. GRB 100424A: Swift-XRT refined analysis
  89. GRB 100425A: Swift detection of a burst
  90. GRB 100424A, Swift-BAT refined analysis
  91. GRB 100424A: Swift detection of a burst
  92. GRB 100420A: GRT Optical Observation
  93. Swift-BAT refined analysis of trigger 420256
  94. Swift Trigger 420256: D50 optical limits
  95. GRB 100420A: Swift-BAT refined analysis
  96. GRB 100423B: Fermi GBM detection
  97. GRB 100423A: Swift-BAT refined analysis
  98. Swift Trigger 420256: IAC80 R-band observations
  99. Swift Trigger 420256: BOOTES-2 observations
  100. Swift Trigger 420256: ROTSE-III Optical Limits

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