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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"

19193 results found.

  1. GRB 061019: Swift/UVOT upper limit
  2. GRB061019: Swift XRT refined analysis
  3. GRB 061019, Swift-BAT refined analysis
  4. GRB 061019: TAROT La Silla observatory optical observations
  5. GRB061019: Swift/XRT position
  6. GRB 061019: Swift-BAT detection of a burst
  7. GRB 061006: astrometry-corrected XRT position
  8. Konus-Wind observation of GRB 061007
  9. GRB 060928: Confirmation of the X-ray afterglow detected by Swift
  10. GRB061007: Swift UVOT followup observations
  11. GRB 061007: Magellan Spectroscopy
  12. GRB 061007: Correction to GCN 5712
  13. GRB 061007: Swift-BAT refined analysis
  14. GRB 061007: Swift XRT refined analysis
  15. GRB 061006: Swift/UVOT optical observations
  16. Konus-Wind observation of the short hard GRB 061006
  17. GRB 061007 - Faulkes Telescope South Afterglow Confirmation
  18. GRB 061007: Swift detection of a burst with an optical counterpart
  19. GRB 061007: ROTSE-III Detection of Optical Counterpart
  20. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  21. GRB 061006: Swift-XRT Team Refined Analysis
  22. GRB061006 (Swift 232585) might be a short-hard GRB
  23. GRB061006: Faulkes Telescope South Observations
  24. GRB 061006: Swift detection of a burst
  25. GRB061004: Swift/UVOT optical observations
  26. GRB 061004: Swift-XRT Team Refined Analysis
  27. GRB 061004, Swift BAT refined analysis
  28. GRB 061004: Swift detection of a burst
  29. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  30. GRB 060928: Swift observations
  31. IPN triangulation of GRB060928 (long, exceptionally bright)
  32. GRB061002: Swift UVOT followup observations
  33. GRB 061002: Swift-XRT Team Refined Analysis
  34. GRB 061002, Swift-BAT refined analysis
  35. GRB061002: MASTER-VWF-Kislovodsk observations
  36. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  37. GRB 061002: Swift detection of a burst
  38. GRB 060929: Further XRT Refined Analysis
  39. GRB 060929: Swift/UVOT Optical Observations
  40. GRB060929: Swift-XRT refined analysis.
  41. GRB 060929, Swift-BAT further refined analysis - late-time flare
  42. GRB 060929, Swift-BAT refined analysis
  43. GRB 060929: BART observation
  44. GRB 060929: MASTER-VWF-Kislovodsk observations
  45. GRB 060929: BOOTES-IR & OSN observations
  46. Liverpool Telescope observations of GRB 060929
  47. GRB 060929: Swift detection of a burst
  48. GRB 060729: An update on the late-time Swift observations
  49. GRB 060926: Swift-UVOT UVW1 Detection Retraction
  50. GRB 060927: pseudo-z from spectral parameters of the prompt emission
  51. GRB 060927: Swift/UVOT Optical Observations
  52. GRB 060927: Swift XRT Team refined analysis
  53. GRB 060927, Swift-BAT refined analysis
  54. GRB060927: Faulkes Telescope South observation
  55. GRB060927 - SDSS Pre-Burst Observations
  56. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  57. Swift XRT boresight
  58. GRB 060927: Swift detection of a burst
  59. GRB060926: VLT redshift
  60. GRB 060926: Swift-UVOT Detections
  61. GRB 060926: Swift XRT refined analysis
  62. GRB 060926, Swift-BAT refined analysis
  63. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  64. GRB 060926: BOOTES-IR observations
  65. GRB060926 OPTIMA-Burst optical observation
  66. GRB 060926: Swift detection of a burst
  67. GRB 060923C, Swift-BAT refined analysis
  68. GRB 060923C: VLA Observation
  69. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  70. GRB060923B: Swift/UVOT upper limits
  71. GRB 060923B: Swift XRT Refined Analysis
  72. GRB 060923C: Swift XRT refined analysis
  73. GRB 060923C, Swift-BAT partial refined analysis
  74. GRB 060923A: Swift XRT refined analysis
  75. GRB 060923A: Keck and Gemini Observations
  76. GRB 060923B, Swift-BAT refined analysis
  77. GRB060923C : Faulkes Telescope South optical limits
  78. GRB060923C: Faulkes Telescope North optical observations
  79. GRB 060923C: Swift detection of a burst
  80. GRB 060923B: Swift detection of a burst
  81. GRB 060923, Swift-BAT refined analysis
  82. GRB 060923: Early Super-LOTIS Observations
  83. GRB060923: Faulkes Telescope North optical observations
  84. GRB 060923: KAIT observations
  85. GRB 060923: Swift detection of a burst
  86. Swift detection of IGR J17497-2821 (trigger 230504)
  87. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  88. GRB060919: Swift/UVOT optical observations
  89. GRB 060919, Swift-BAT refined analysis
  90. GRB060919: XRT refined analysis
  91. GRB 060919: TAROT optical observations
  92. GRB 060919: Swift detection of a burst
  93. GRB 060912A: VLA Observation
  94. GRB060825: MAGIC telescope GeV observation
  95. Konus-Wind observation of GRB 060912
  96. GRB060912: Swift/UVOT Observations
  97. GRB060912: OPTIMA-Burst optical observations
  98. GRB 060912: Swift XRT Team Refined Analysis
  99. GRB 060912, Swift-BAT refined analysis
  100. GRB 060912: Swift detection of a burst with an optical afterglow

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