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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').

17956 results found.

  1. GRB 061121: Swift/UVOT Observations
  2. GRB 061121: Swift-XRT Team Refined Analysis
  3. GRB 061121, Swift-BAT refined analysis
  4. GRB061121, optical observation
  5. GRB 061121: Faulkes Telescope North Optical Observation
  6. GRB 061121: ROTSE-III Confirmation of Optical Counterpart
  7. GRB 061121: Swift detection of a bright burst with an optical counterpart
  8. GRB 060111B: Swift UVOT Refined Magnitudes
  9. Swift-BAT triggers 238544 and 238546 are not GRBs
  10. Swift TOO observations of GRB061110A
  11. Swift/UVOT Upper Limits for GRB061110b
  12. Swift/UVOT Upper Limits for GRB061110a
  13. GRB 061110B: Swift XRT refined analysis
  14. GRB 061110B, Swift-BAT refined analysis
  15. GRB061110B: Optical observations at Crni Vrh
  16. GRB 061110A: Swift XRT refined analysis
  17. GRB 061110B: Swift/XRT position
  18. GRB 061110B: Swift-UVOT Initial Observation
  19. GRB 061110A, Swift-BAT refined analysis
  20. GRB 061110B: TAROT Calern observatory optical observations
  21. GRB 061110B: Swift detection of a burst
  22. GRB 061110: ROTSE-III Optical Limits
  23. GRB 061110: Swift detection of a burst
  24. Swift-BAT Trigger 237821 is a Cosmic Ray Shower event
  25. GRB 061109: TAROT Calern observatory optical observations
  26. GRB 061109: Swift detection of a possible burst
  27. GRB061028: MAGIC telescope GeV observation
  28. GRB 061027: TAROT La Silla observatory optical observations
  29. GRB 061028: Swift/XRT Astrometry Correction
  30. GRB 061102: Swift/UVOT Magnitude Upper Limits
  31. GRB 061102, XRT refined analysis
  32. Swift-BAT Trigger 236481 is a Cosmic Ray Shower event
  33. GRB061102B: Super-LOTIS observations
  34. GRB 061028: Optical R passband observations
  35. GRB 061102B: Swift detection of a possible burst
  36. GRB 061102, Swift-BAT refined analysis
  37. GRB 061102: Swift detection of a burst
  38. GRB 061028: VLA Observation
  39. GRB 061004: Swift/XRT Astrometry Correction
  40. GRB 060801: Swift/XRT Astrometry Correction
  41. GRB 061028: MDM Observations
  42. GRB 061028: SARA upper limit
  43. GRB061028: XRT refined analysis
  44. GRB 061028: Swift/UVOT Observations
  45. GRB 061028, Swift-BAT refined analysis
  46. GRB 061028: TAROT Calern observatory optical observations
  47. GRB 061028: Swift detection of a burst
  48. GRB 061027, Swift refined analysis of a possible burst
  49. GRB 061027: Swift detection of a possible burst
  50. GRB061025: Swift XRT refined analysis
  51. GRB061025: Swift/UVOT observations
  52. GRB061025: Swift XRT position
  53. Swift XRT boresight update
  54. GRB 061021, Swift-BAT Lag analysis
  55. Konus-Wind observation of GRB 061021
  56. GRB 061021: Swift-XRT refined analysis
  57. GRB 061021: Swift/UVOT Observation
  58. GRB 061021, Swift-BAT refined analysis
  59. GRB 061021: Swift detection of a burst
  60. GRB 061019: Super-LOTIS upper limit
  61. GRB 061019: SARA upper limit
  62. GRB 061019: dust-scattered X-ray halo detected in Swift/XRT
  63. GRB 061019: Swift/UVOT upper limit
  64. GRB061019: Swift XRT refined analysis
  65. GRB 061019, Swift-BAT refined analysis
  66. GRB 061019: TAROT La Silla observatory optical observations
  67. GRB061019: Swift/XRT position
  68. GRB 061019: Swift-BAT detection of a burst
  69. GRB 061006: astrometry-corrected XRT position
  70. Konus-Wind observation of GRB 061007
  71. GRB 060928: Confirmation of the X-ray afterglow detected by Swift
  72. GRB061007: Swift UVOT followup observations
  73. GRB 061007: Magellan Spectroscopy
  74. GRB 061007: Correction to GCN 5712
  75. GRB 061007: Swift-BAT refined analysis
  76. GRB 061007: Swift XRT refined analysis
  77. GRB 061006: Swift/UVOT optical observations
  78. Konus-Wind observation of the short hard GRB 061006
  79. GRB 061007 - Faulkes Telescope South Afterglow Confirmation
  80. GRB 061007: Swift detection of a burst with an optical counterpart
  81. GRB 061007: ROTSE-III Detection of Optical Counterpart
  82. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  83. GRB 061006: Swift-XRT Team Refined Analysis
  84. GRB061006 (Swift 232585) might be a short-hard GRB
  85. GRB061006: Faulkes Telescope South Observations
  86. GRB 061006: Swift detection of a burst
  87. GRB061004: Swift/UVOT optical observations
  88. GRB 061004: Swift-XRT Team Refined Analysis
  89. GRB 061004, Swift BAT refined analysis
  90. GRB 061004: Swift detection of a burst
  91. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  92. GRB 060928: Swift observations
  93. IPN triangulation of GRB060928 (long, exceptionally bright)
  94. GRB061002: Swift UVOT followup observations
  95. GRB 061002: Swift-XRT Team Refined Analysis
  96. GRB 061002, Swift-BAT refined analysis
  97. GRB061002: MASTER-VWF-Kislovodsk observations
  98. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  99. GRB 061002: Swift detection of a burst
  100. GRB 060929: Further XRT Refined Analysis

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