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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"

19589 results found.

  1. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  2. GRB061126 : NMSU 1.0m observations
  3. GRB 061202: Swift XRT refined analysis
  4. GRB061202: FRAM early follow-up limit
  5. GRB061202 optical limit by "Pi of the Sky"
  6. Konus-Wind observation of GRB 061201
  7. GRB061202: Swift/UVOT Upper Limits
  8. GRB 061202, Swift-BAT refined analysis
  9. GRB 061202: Swift detection of a burst
  10. GRB 061201: Swift XRT Team refined analysis
  11. GRB 061201: Initial UVOT Observations
  12. GRB 061201, Swift-BAT refined analysis of the SHB
  13. GRB 061201: Swift detection of a short hard burst
  14. GRB 061201: Coincidence with a Galaxy Cluster
  15. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  16. Swift XRT on-board boresight update
  17. GRB 061126: Early Super-LOTIS Observations
  18. GRB061126: Optical afterglow observations from MIRO
  19. GRB061126: Optical afterglow observations from MIRO
  20. GRB 061126: Swift-XRT refined analysis
  21. GRB 061126: Swift/UVOT Observations
  22. GRB 061126, Swift-BAT refined analysis
  23. GRB 061126: Faulkes Telescope North Optical Observations
  24. GRB 061126: Swift/UVOT Afterglow Detection
  25. GRB 061126: XRT position
  26. GRB 061126: Swift detection of a burst
  27. GRB 061122: Confirmation of X-ray/Optical Afterglow
  28. GRB 061122: Candidate Optical Afterglow
  29. GRB 061121: Ep,i - Eiso correlation
  30. GRB061122: Swift/UVOT Optical Observations
  31. GRB061122: Swift-XRT position
  32. GRB 061121 declared "Burst of Interest" by Swift team
  33. Konus-Wind and Konus-A observations of GRB 061121
  34. Swift-BAT trigger 239987 is not a GRB
  35. GRB 061121: Swift/UVOT Observations
  36. GRB 061121: Swift-XRT Team Refined Analysis
  37. GRB 061121, Swift-BAT refined analysis
  38. GRB061121, optical observation
  39. GRB 061121: Faulkes Telescope North Optical Observation
  40. GRB 061121: ROTSE-III Confirmation of Optical Counterpart
  41. GRB 061121: Swift detection of a bright burst with an optical counterpart
  42. GRB 060111B: Swift UVOT Refined Magnitudes
  43. Swift-BAT triggers 238544 and 238546 are not GRBs
  44. Swift TOO observations of GRB061110A
  45. Swift/UVOT Upper Limits for GRB061110b
  46. Swift/UVOT Upper Limits for GRB061110a
  47. GRB 061110B: Swift XRT refined analysis
  48. GRB 061110B, Swift-BAT refined analysis
  49. GRB061110B: Optical observations at Crni Vrh
  50. GRB 061110A: Swift XRT refined analysis
  51. GRB 061110B: Swift/XRT position
  52. GRB 061110B: Swift-UVOT Initial Observation
  53. GRB 061110A, Swift-BAT refined analysis
  54. GRB 061110B: TAROT Calern observatory optical observations
  55. GRB 061110B: Swift detection of a burst
  56. GRB 061110: ROTSE-III Optical Limits
  57. GRB 061110: Swift detection of a burst
  58. Swift-BAT Trigger 237821 is a Cosmic Ray Shower event
  59. GRB 061109: TAROT Calern observatory optical observations
  60. GRB 061109: Swift detection of a possible burst
  61. GRB061028: MAGIC telescope GeV observation
  62. GRB 061027: TAROT La Silla observatory optical observations
  63. GRB 061028: Swift/XRT Astrometry Correction
  64. GRB 061102: Swift/UVOT Magnitude Upper Limits
  65. GRB 061102, XRT refined analysis
  66. Swift-BAT Trigger 236481 is a Cosmic Ray Shower event
  67. GRB061102B: Super-LOTIS observations
  68. GRB 061028: Optical R passband observations
  69. GRB 061102B: Swift detection of a possible burst
  70. GRB 061102, Swift-BAT refined analysis
  71. GRB 061102: Swift detection of a burst
  72. GRB 061028: VLA Observation
  73. GRB 061004: Swift/XRT Astrometry Correction
  74. GRB 060801: Swift/XRT Astrometry Correction
  75. GRB 061028: MDM Observations
  76. GRB 061028: SARA upper limit
  77. GRB061028: XRT refined analysis
  78. GRB 061028: Swift/UVOT Observations
  79. GRB 061028, Swift-BAT refined analysis
  80. GRB 061028: TAROT Calern observatory optical observations
  81. GRB 061028: Swift detection of a burst
  82. GRB 061027, Swift refined analysis of a possible burst
  83. GRB 061027: Swift detection of a possible burst
  84. GRB061025: Swift XRT refined analysis
  85. GRB061025: Swift/UVOT observations
  86. GRB061025: Swift XRT position
  87. Swift XRT boresight update
  88. GRB 061021, Swift-BAT Lag analysis
  89. Konus-Wind observation of GRB 061021
  90. GRB 061021: Swift-XRT refined analysis
  91. GRB 061021: Swift/UVOT Observation
  92. GRB 061021, Swift-BAT refined analysis
  93. GRB 061021: Swift detection of a burst
  94. GRB 061019: Super-LOTIS upper limit
  95. GRB 061019: SARA upper limit
  96. GRB 061019: dust-scattered X-ray halo detected in Swift/XRT
  97. GRB 061019: Swift/UVOT upper limit
  98. GRB061019: Swift XRT refined analysis
  99. GRB 061019, Swift-BAT refined analysis
  100. GRB 061019: TAROT La Silla observatory optical observations

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