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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"

19935 results found.

  1. GRB 061021, Swift-BAT refined analysis
  2. GRB 061021: Swift detection of a burst
  3. GRB 061019: Super-LOTIS upper limit
  4. GRB 061019: SARA upper limit
  5. GRB 061019: dust-scattered X-ray halo detected in Swift/XRT
  6. GRB 061019: Swift/UVOT upper limit
  7. GRB061019: Swift XRT refined analysis
  8. GRB 061019, Swift-BAT refined analysis
  9. GRB 061019: TAROT La Silla observatory optical observations
  10. GRB061019: Swift/XRT position
  11. GRB 061019: Swift-BAT detection of a burst
  12. GRB 061006: astrometry-corrected XRT position
  13. Konus-Wind observation of GRB 061007
  14. GRB 060928: Confirmation of the X-ray afterglow detected by Swift
  15. GRB061007: Swift UVOT followup observations
  16. GRB 061007: Magellan Spectroscopy
  17. GRB 061007: Correction to GCN 5712
  18. GRB 061007: Swift-BAT refined analysis
  19. GRB 061007: Swift XRT refined analysis
  20. GRB 061006: Swift/UVOT optical observations
  21. Konus-Wind observation of the short hard GRB 061006
  22. GRB 061007 - Faulkes Telescope South Afterglow Confirmation
  23. GRB 061007: Swift detection of a burst with an optical counterpart
  24. GRB 061007: ROTSE-III Detection of Optical Counterpart
  25. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  26. GRB 061006: Swift-XRT Team Refined Analysis
  27. GRB061006 (Swift 232585) might be a short-hard GRB
  28. GRB061006: Faulkes Telescope South Observations
  29. GRB 061006: Swift detection of a burst
  30. GRB061004: Swift/UVOT optical observations
  31. GRB 061004: Swift-XRT Team Refined Analysis
  32. GRB 061004, Swift BAT refined analysis
  33. GRB 061004: Swift detection of a burst
  34. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  35. GRB 060928: Swift observations
  36. IPN triangulation of GRB060928 (long, exceptionally bright)
  37. GRB061002: Swift UVOT followup observations
  38. GRB 061002: Swift-XRT Team Refined Analysis
  39. GRB 061002, Swift-BAT refined analysis
  40. GRB061002: MASTER-VWF-Kislovodsk observations
  41. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  42. GRB 061002: Swift detection of a burst
  43. GRB 060929: Further XRT Refined Analysis
  44. GRB 060929: Swift/UVOT Optical Observations
  45. GRB060929: Swift-XRT refined analysis.
  46. GRB 060929, Swift-BAT further refined analysis - late-time flare
  47. GRB 060929, Swift-BAT refined analysis
  48. GRB 060929: BART observation
  49. GRB 060929: MASTER-VWF-Kislovodsk observations
  50. GRB 060929: BOOTES-IR & OSN observations
  51. Liverpool Telescope observations of GRB 060929
  52. GRB 060929: Swift detection of a burst
  53. GRB 060729: An update on the late-time Swift observations
  54. GRB 060926: Swift-UVOT UVW1 Detection Retraction
  55. GRB 060927: pseudo-z from spectral parameters of the prompt emission
  56. GRB 060927: Swift/UVOT Optical Observations
  57. GRB 060927: Swift XRT Team refined analysis
  58. GRB 060927, Swift-BAT refined analysis
  59. GRB060927: Faulkes Telescope South observation
  60. GRB060927 - SDSS Pre-Burst Observations
  61. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  62. Swift XRT boresight
  63. GRB 060927: Swift detection of a burst
  64. GRB060926: VLT redshift
  65. GRB 060926: Swift-UVOT Detections
  66. GRB 060926: Swift XRT refined analysis
  67. GRB 060926, Swift-BAT refined analysis
  68. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  69. GRB 060926: BOOTES-IR observations
  70. GRB060926 OPTIMA-Burst optical observation
  71. GRB 060926: Swift detection of a burst
  72. GRB 060923C, Swift-BAT refined analysis
  73. GRB 060923C: VLA Observation
  74. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  75. GRB060923B: Swift/UVOT upper limits
  76. GRB 060923B: Swift XRT Refined Analysis
  77. GRB 060923C: Swift XRT refined analysis
  78. GRB 060923C, Swift-BAT partial refined analysis
  79. GRB 060923A: Swift XRT refined analysis
  80. GRB 060923A: Keck and Gemini Observations
  81. GRB 060923B, Swift-BAT refined analysis
  82. GRB060923C : Faulkes Telescope South optical limits
  83. GRB060923C: Faulkes Telescope North optical observations
  84. GRB 060923C: Swift detection of a burst
  85. GRB 060923B: Swift detection of a burst
  86. GRB 060923, Swift-BAT refined analysis
  87. GRB 060923: Early Super-LOTIS Observations
  88. GRB060923: Faulkes Telescope North optical observations
  89. GRB 060923: KAIT observations
  90. GRB 060923: Swift detection of a burst
  91. Swift detection of IGR J17497-2821 (trigger 230504)
  92. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  93. GRB060919: Swift/UVOT optical observations
  94. GRB 060919, Swift-BAT refined analysis
  95. GRB060919: XRT refined analysis
  96. GRB 060919: TAROT optical observations
  97. GRB 060919: Swift detection of a burst
  98. GRB 060912A: VLA Observation
  99. GRB060825: MAGIC telescope GeV observation
  100. Konus-Wind observation of GRB 060912

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