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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"

18634 results found.

  1. GRB 061110: ROTSE-III Optical Limits
  2. GRB 061110: Swift detection of a burst
  3. Swift-BAT Trigger 237821 is a Cosmic Ray Shower event
  4. GRB 061109: TAROT Calern observatory optical observations
  5. GRB 061109: Swift detection of a possible burst
  6. GRB061028: MAGIC telescope GeV observation
  7. GRB 061027: TAROT La Silla observatory optical observations
  8. GRB 061028: Swift/XRT Astrometry Correction
  9. GRB 061102: Swift/UVOT Magnitude Upper Limits
  10. GRB 061102, XRT refined analysis
  11. Swift-BAT Trigger 236481 is a Cosmic Ray Shower event
  12. GRB061102B: Super-LOTIS observations
  13. GRB 061028: Optical R passband observations
  14. GRB 061102B: Swift detection of a possible burst
  15. GRB 061102, Swift-BAT refined analysis
  16. GRB 061102: Swift detection of a burst
  17. GRB 061028: VLA Observation
  18. GRB 061004: Swift/XRT Astrometry Correction
  19. GRB 060801: Swift/XRT Astrometry Correction
  20. GRB 061028: MDM Observations
  21. GRB 061028: SARA upper limit
  22. GRB061028: XRT refined analysis
  23. GRB 061028: Swift/UVOT Observations
  24. GRB 061028, Swift-BAT refined analysis
  25. GRB 061028: TAROT Calern observatory optical observations
  26. GRB 061028: Swift detection of a burst
  27. GRB 061027, Swift refined analysis of a possible burst
  28. GRB 061027: Swift detection of a possible burst
  29. GRB061025: Swift XRT refined analysis
  30. GRB061025: Swift/UVOT observations
  31. GRB061025: Swift XRT position
  32. Swift XRT boresight update
  33. GRB 061021, Swift-BAT Lag analysis
  34. Konus-Wind observation of GRB 061021
  35. GRB 061021: Swift-XRT refined analysis
  36. GRB 061021: Swift/UVOT Observation
  37. GRB 061021, Swift-BAT refined analysis
  38. GRB 061021: Swift detection of a burst
  39. GRB 061019: Super-LOTIS upper limit
  40. GRB 061019: SARA upper limit
  41. GRB 061019: dust-scattered X-ray halo detected in Swift/XRT
  42. GRB 061019: Swift/UVOT upper limit
  43. GRB061019: Swift XRT refined analysis
  44. GRB 061019, Swift-BAT refined analysis
  45. GRB 061019: TAROT La Silla observatory optical observations
  46. GRB061019: Swift/XRT position
  47. GRB 061019: Swift-BAT detection of a burst
  48. GRB 061006: astrometry-corrected XRT position
  49. Konus-Wind observation of GRB 061007
  50. GRB 060928: Confirmation of the X-ray afterglow detected by Swift
  51. GRB061007: Swift UVOT followup observations
  52. GRB 061007: Magellan Spectroscopy
  53. GRB 061007: Correction to GCN 5712
  54. GRB 061007: Swift-BAT refined analysis
  55. GRB 061007: Swift XRT refined analysis
  56. GRB 061006: Swift/UVOT optical observations
  57. Konus-Wind observation of the short hard GRB 061006
  58. GRB 061007 - Faulkes Telescope South Afterglow Confirmation
  59. GRB 061007: Swift detection of a burst with an optical counterpart
  60. GRB 061007: ROTSE-III Detection of Optical Counterpart
  61. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  62. GRB 061006: Swift-XRT Team Refined Analysis
  63. GRB061006 (Swift 232585) might be a short-hard GRB
  64. GRB061006: Faulkes Telescope South Observations
  65. GRB 061006: Swift detection of a burst
  66. GRB061004: Swift/UVOT optical observations
  67. GRB 061004: Swift-XRT Team Refined Analysis
  68. GRB 061004, Swift BAT refined analysis
  69. GRB 061004: Swift detection of a burst
  70. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  71. GRB 060928: Swift observations
  72. IPN triangulation of GRB060928 (long, exceptionally bright)
  73. GRB061002: Swift UVOT followup observations
  74. GRB 061002: Swift-XRT Team Refined Analysis
  75. GRB 061002, Swift-BAT refined analysis
  76. GRB061002: MASTER-VWF-Kislovodsk observations
  77. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  78. GRB 061002: Swift detection of a burst
  79. GRB 060929: Further XRT Refined Analysis
  80. GRB 060929: Swift/UVOT Optical Observations
  81. GRB060929: Swift-XRT refined analysis.
  82. GRB 060929, Swift-BAT further refined analysis - late-time flare
  83. GRB 060929, Swift-BAT refined analysis
  84. GRB 060929: BART observation
  85. GRB 060929: MASTER-VWF-Kislovodsk observations
  86. GRB 060929: BOOTES-IR & OSN observations
  87. Liverpool Telescope observations of GRB 060929
  88. GRB 060929: Swift detection of a burst
  89. GRB 060729: An update on the late-time Swift observations
  90. GRB 060926: Swift-UVOT UVW1 Detection Retraction
  91. GRB 060927: pseudo-z from spectral parameters of the prompt emission
  92. GRB 060927: Swift/UVOT Optical Observations
  93. GRB 060927: Swift XRT Team refined analysis
  94. GRB 060927, Swift-BAT refined analysis
  95. GRB060927: Faulkes Telescope South observation
  96. GRB060927 - SDSS Pre-Burst Observations
  97. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  98. Swift XRT boresight
  99. GRB 060927: Swift detection of a burst
  100. GRB060926: VLT redshift

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