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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"

27022 results found.

  1. GRB 110915A, Swift-BAT refined analysis
  2. GRB 110915A: Swift-XRT refined Analysis
  3. GRB 110915B: XRT afterglow candidate
  4. GRB 110903A: Suzaku WAM observation of the prompt emission
  5. GRB110915A MITSuME Okayama J-band upper-limit
  6. GRB 110915A: MITSuME Akeno Optical upper limits
  7. GRB 110915A: Swift detection of a burst
  8. GRB 110906A(?): Burst detection (unconfirmed) from Swift-BAT slew data
  9. MAXI J1836-194 (originally GRB 110905A): Swift-BAT refined analysis
  10. GRB 110905A: Potential BAT trigger on MAXI J1836-194
  11. GRB 110905A: KAIT observations
  12. GRB 110905A: Swift detection of a burst
  13. GRB 110903A: Fermi GBM observation
  14. GRB 110903A: Swift/UVOT Upper Limits
  15. GRB 110903A: Swift-XRT observations
  16. GRB 110820A: optical upper limit
  17. SGR Swift J1834.9-0846: Correction to the Swift-BAT refined spectral analysis
  18. Trigger 502024: Swift detection of KS 1741-293
  19. GRB110825A: Fermi GBM observation
  20. SGR Swift J1834.9-0846: Swift-BAT refined analysis of trigger 501752
  21. Swift detection of an SGR burst from Swift J1834.9-0846
  22. GRB 110825A: Suzaku WAM observation of the prompt emission
  23. GRB110825A: ROTSE early time optical limit
  24. GRB 110827A, Swift-BAT refined analysis
  25. GRB 110827A: Swift detection of a burst
  26. GRB110825A: Swift target of opportunity observation
  27. IPN triangulation of GRB110825A (very intense, long-duration)
  28. Swift-BAT Trigger 501485 is noise
  29. Swift-BAT refined analysis of SFXT IGR J08408-4503 (trigger 501368)
  30. Fermi GBM trigger 110823.518 is not a GRB
  31. GRB 110820A: Swift/UVOT Upper Limits
  32. GRB 110820A: CQUEAN izY Observation
  33. GRB 110820A: Swift-XRT refined Analysis
  34. GRB 110820A: Swift-BAT refined analysis
  35. GRB 110820A: Swift detection of a burst
  36. GRB 110818A: Fermi GBM observation
  37. GRB 110818A: Swift/UVOT Upper Limits
  38. GRB 110818A: Swift-XRT refined Analysis
  39. GRB 110815A: Swift-XRT and UVOT refined Analysis
  40. GRB 110818A, Swift-BAT refined analysis
  41. GRB 110815A : Suzaku WAM observation of the prompt emission
  42. GRB 110818A: Swift detection of a burst
  43. GRB 110801A: Konus-Wind and Swift/BAT joint spectral analysis
  44. Fermi Gamma-ray Burst Monitor trigger 110809.346 is not a GRB
  45. GRB 110808A: Swift/UVOT Detection
  46. Swift Trigger 458942 is probably not a burst
  47. GRB 110808A: Swift-BAT refined analysis
  48. GRB 110808A: Swift-XRT refined Analysis
  49. SGR J1834.9-0846: A Neutron Star in W41?
  50. Swift SGR 1834.9-0846: Swift-BAT refined analysis
  51. GRB 110808A: Swift detection of a burst with optical counterpart
  52. Fermi GBM detection of a SGR-like burst
  53. GRB 110807A: SAO RAS observations
  54. GRB 110807A: Swift detection of a burst or a posible new SGR
  55. Fermi Gamma-ray Burst Monitor trigger 110806.263 is not a GRB
  56. Fermi GBM trigger 334123030 (110804165) is not a GRB
  57. GRB 110731A : Suzaku WAM observation of the prompt emission
  58. GRB 110726A: Swift-XRT refined Analysis
  59. GRB110731A: MOA optical observations of the steeply fading afterglow
  60. GRB 110801A: SAO RAS optical observations
  61. GRB 110801A: Evidence for a jet break
  62. GRB 110801A: MASTER OT observations
  63. GRB 110801A: Swift-BAT refined analysis
  64. Swift/UVOT observations of GRB110801A
  65. GRB 110801A: Swift-XRT refined Analysis
  66. AXP 4U 0142+61: Fermi GBM detection
  67. GRB 110801A: TLS Optical afterglow confirmation
  68. GRB 110801A: ROTSE-III Detection of re-brightening from OT
  69. GRB 110801A: Swift detection of a burst with an optical counterpart
  70. GRB 110731A: Swift-XRT refined Analysis
  71. Konus-Wind observation of GRB 110731A
  72. GRB110731A: Swift/UVOT Observations
  73. GRB 110731A: Fermi GBM observation
  74. GRB 110731A: NOT photometry
  75. GRB 110731A: Swift-BAT refined analysis
  76. GRB 110731A: FTN+FTS afterglow observations
  77. GRB 110731A: Swift detection of a burst with an optical counterpart
  78. INTEGRAL Weak trigger #6331: GRT Optical Observation
  79. GRB 110721A: Swift observations of afterglow candidate
  80. AXP 4U 0142+61: Swift-BAT refined analysis
  81. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  82. Swift triggers 458268 and 458269 are not astrophysical
  83. GRB 110726A: Further Swift/UVOT Observations
  84. GRB 110726A: Swift-BAT refined analysis
  85. GRB 110726A: Swift/UVOT Detection
  86. GRB 110726A: Liverpool Telescope observations
  87. GRB 110726: ROTSE-III Detection of Optical Counterpart
  88. GRB 110726A: Swift detection of a burst
  89. GRB 110721A: Preliminary Swift/UVOT Upper Limits
  90. GRB 110721A: potential counterpart candidate
  91. GRB 110721A: Fermi-LAT detection
  92. GRB 110721A: Fermi GBM detection
  93. GRB110715A: spectral lag analysis
  94. GRB 110715A : Suzaku WAM observation of the prompt emission
  95. GRB 110719A: GRT Optical Observation
  96. Swift/UVOT observations of GRB110719A
  97. Swift J1822.3-1606 : Fermi GBM observation
  98. GRB 110719A: Swift-XRT refined Analysis
  99. GRB 110719A: Swift-BAT refined analysis
  100. GRB 110719A: Swift detection of a burst

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