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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"

24046 results found.

  1. Swift-BAT trigger 421695 is likely not astrophysical
  2. GRB 100510A: MAXI/GSC detection
  3. GRB 100511A, RIMOTS optical upper limits
  4. Trigger 421695: Swift detection of a possible burst
  5. GRB100508A: Further Swift/UVOT Observations
  6. GRB100503A: Suzaku WAM observation of the prompt emission
  7. GRB 100508A: GROND Detection of the optical afterglow
  8. GRB 100508A: Swift-XRT Refined analysis
  9. GRB 100508A: Swift-BAT refined analysis
  10. GRB100508A: Swift/UVOT Detection of the Afterglow
  11. GRB 100508A: ROTSE-III Optical Limits
  12. GRB 100508A: Swift detection of a burst
  13. Fermi Gamma-ray Burst Monitor trigger 294712621 is not a GRB
  14. Swift-BAT refined analysis of trigger 421262
  15. GRB 100504A: Fermi GBM observation
  16. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  17. GRB 100504A: Swift/UVOT Observations
  18. GRB 100418A: Flattening of the Swift/UVOT Optical Light Curve
  19. GRB 100504A: GROND Upper limits
  20. GRB 100504A: Swift-BAT refined analysis
  21. GRB 100504A: SARA-South Upper Limit
  22. GRB 100503A: Fermi GBM detection
  23. GRB 100504A: UVOT-enhanced XRT position
  24. GRB 100504A: Swift detection of a burst
  25. Swift-BAT trigger 421072 is not astrophyical
  26. INTEGRAL observations of Swift GRB trigger 421072
  27. Trigger 421072: Possible Swift detection of a GRB or transient
  28. GRB 100427A: Swift XRT and UVOT Upper Limits
  29. GRB 100427A: Fermi GBM detection
  30. GRB 100427A detected in ground analysis of Swift BAT data
  31. Konus-Wind observation of GRB 100423A
  32. GRB 100425A: Swift XRT refined analysis
  33. GRB100425A: Swift/UVOT Upper Limits
  34. GRB 100424A: Swift/UVOT Upper Limits
  35. GRB 100425A: Swift-BAT refined analysis
  36. GRB 100425A: GROND afterglow observation
  37. GRB 100424A: D50 optical limits
  38. GRB 100424A : Lulin early z'-band upper limit
  39. GRB 100424A: GROND Upper Limits
  40. GRB 100424A: PAIRITEL NIR Upper Limits
  41. GRB 100424A: Swift-XRT refined analysis
  42. GRB 100425A: Swift detection of a burst
  43. GRB 100424A, Swift-BAT refined analysis
  44. GRB 100424A: Swift detection of a burst
  45. GRB 100420A: GRT Optical Observation
  46. Swift-BAT refined analysis of trigger 420256
  47. Swift Trigger 420256: D50 optical limits
  48. GRB 100420A: Swift-BAT refined analysis
  49. GRB 100423B: Fermi GBM detection
  50. GRB 100423A: Swift-BAT refined analysis
  51. Swift Trigger 420256: IAC80 R-band observations
  52. Swift Trigger 420256: BOOTES-2 observations
  53. Swift Trigger 420256: ROTSE-III Optical Limits
  54. Trigger 420256: Swift detection of a possible GRB
  55. GRB 100423A: Skynet/PROMPT Detections
  56. GRB 100423A: GROND discovery of afterglow
  57. GRB 100423A: Swift detection of a burst
  58. GRB 100418A: Continued PAIRITEL NIR Observations
  59. GRB 100414A: CFHT optical observations
  60. GRB 100420A: Swift/UVOT Upper Limits
  61. GRB 100420A: XRT refined analysis
  62. GRB 100418A: SARA second epoch
  63. GRB 100420A: SARA Upper Limits
  64. GRB 100418A: MASTER-Net optical observations
  65. GRB 100414A: Confirmation of the X-ray afterglow
  66. GRB 100420A: ROTSE-III Optical Limits
  67. GRB 100420A: Swift detection of a burst
  68. GRB 100418A PAIRITEL NIR Observations
  69. GRB 100418A: Swift/UVOT Observations
  70. GRB 100418A: Swift-XRT Refined Analysis
  71. GRB 100418A: SARA observations
  72. GRB 100418A: Swift-BAT refined analysis
  73. GRB 100418A: ROTSE-III Optical Limits
  74. GRB 100418A: Swift detection of a burst with a possible optical afterglow
  75. GRB 100413A: Radio Afterglow Detection with the EVLA
  76. GRB 100414A: Suzaku WAM observation of the prompt emission
  77. GRB 100414A: Swift/UVOT Observations
  78. GRB 100414A: GROND Detection of the Optical Afterglow
  79. GRB 100413A: Suzaku WAM observation of the prompt emission
  80. GRB 100414A: Palomar Transient Factory Observations
  81. GRB 100413B: Swift Confirmation of Burst
  82. GRB 100414A: Swift-XRT detection of a possible X-ray afterglow
  83. GRB 100413A: Swift-BAT final refined analysis
  84. GRB 100414A: Fermi GBM detection
  85. GRB100414A: Fermi LAT detection
  86. GRB 100413B : Swift detection of a burst
  87. GRB 100413A: GROND Upper limits
  88. GRB 100413A: Swift/UVOT Upper Limits
  89. Konus-Wind observation of GRB 100413A
  90. GRB 100413A: Faulkes Telescope South observations
  91. GRB 100413A: SARA upper limit
  92. GRB 100413A: Swift-XRT Refined Analysis
  93. GRB 100413A: Swift-BAT initial refined analysis
  94. GRB 100413A: MASTER-Net optical observations
  95. GRB 100413A: Swift detection of a burst
  96. Swift-BAT trigger 419015 is not astrophysical
  97. Trigger 419015 is probably not a GRB
  98. INTEGRAL Alert n. 5995: MASTER-Net optical observations
  99. MASTER observations on the Swift second trigger on LS V +44 17
  100. IBAS Alert n. 5996: not a GRB

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