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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

14854 results found.

  1. GRB 070125: UVOT Detection in Ultraviolet Filters
  2. GRB 070125: SARA detection in R
  3. GRB 070126?: Swift detection of a possible burst
  4. IPN-BAT localization of GRB070125 (very long duration, intense)
  5. GRB 070110: Continued Detection and Request for Ground Followup
  6. GRB 070110 declared a "Burst of Interest" by Swift team
  7. Further Retractions of previous Swift-BAT triggers
  8. Trigger 255685: Swift detection of a possible burst
  9. GRB 070110: VLT absorption redshift
  10. GRB 070110: Swift detection of a burst with a possible optical afterglow
  11. GRB 070107: Swift detection of a burst
  12. VLA detection of GRB 061222A
  13. GRB 070103: Swift detection of a burst
  14. Retractions of previous Swift-BAT triggers
  15. GRB 050826: MDM Redshift
  16. GRB 061222B: TAROT La Silla observatory early optical observations
  17. GRB 061222B: BOOTES-IR optical observations
  18. GRB 061222B: Swift detection of a burst
  19. GRB 061222: Swift detection of a burst
  20. GRB 061217: optical observations at Calar Alto
  21. GRB 061217: Swift detection of a short hard burst
  22. GRB 061214(?): Swift detection of a possible burst
  23. GRB 061210: Swift-BAT detection of a short burst
  24. GRB061126: update on the Swift-XRT afterglow light curve
  25. GRB 061202: Swift detection of a burst
  26. GRB 061201: Swift detection of a short hard burst
  27. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  28. GRB 061121: ATCA & WSRT Radio Observations
  29. GRB 061126: Swift/UVOT Observations
  30. GRB 061126: Early Detection of the IR Afterglow
  31. GRB 061126: Faulkes Telescope North Optical Observations
  32. GRB 061126: Swift/UVOT Afterglow Detection
  33. GRB 061126: Swift detection of a burst
  34. GRB 061121: ART detection in Ic
  35. Radio detection of GRB 061121
  36. GRB 061121: Faulkes Telescope North Optical Observation
  37. GRB061121: Spectroscopic Redshift
  38. GRB 061121: Swift detection of a bright burst with an optical counterpart
  39. GRB 060111B: Swift UVOT Refined Magnitudes
  40. GRB 061110A - VLT tentative redshift
  41. GRB 061110A: Swift XRT refined analysis
  42. GRB 061110B : Liverpool Telescope Optical Afterglow Detection
  43. GRB 061110B: Swift detection of a burst
  44. GRB 061110: Swift detection of a burst
  45. GRB061110A - Optical Non-detection
  46. GRB 061109: Swift detection of a possible burst
  47. GRB 061028: Optical R passband observations
  48. GRB 061102B: Swift detection of a possible burst
  49. GRB 061102: Swift detection of a burst
  50. GRB 061028: VLA Observation
  51. GRB061028: XRT refined analysis
  52. GRB 061028: Swift detection of a burst
  53. GRB 061027, Swift refined analysis of a possible burst
  54. GRB 061027: Swift detection of a possible burst
  55. GRB061025: ROTSE-III Confirmation of Optical Counterpart
  56. GRB 061021: Swift detection of a burst
  57. GRB 061019: SMARTS afterglow confirmation
  58. GRB 061019: Swift-BAT detection of a burst
  59. GRB061007: Swift UVOT followup observations
  60. GRB 061007: Swift-BAT refined analysis
  61. GRB 061007: Swift detection of a burst with an optical counterpart
  62. GRB 061007: ROTSE-III Detection of Optical Counterpart
  63. GRB 061006: Swift detection of a burst
  64. GRB 061004: Swift detection of a burst
  65. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  66. GRB 060928: Swift observations
  67. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  68. GRB 061002: Swift detection of a burst
  69. GRB 060908: Detection of a possible host
  70. GRB 060923A: Probable host galaxy in the R-band
  71. GRB 060807: Detection of a possible host galaxy
  72. GRB 060929: Swift detection of a burst
  73. GRB 060729: An update on the late-time Swift observations
  74. GRB 060926: Swift-UVOT UVW1 Detection Retraction
  75. GRB 060927: Early color
  76. GRB060926: improved redshift
  77. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  78. GRB 060927: Swift detection of a burst
  79. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  80. GRB 060926: Swift detection of a burst
  81. GRB 060923C: VLA Observation
  82. GRB 060923C: Swift detection of a burst
  83. GRB 060923B: Swift detection of a burst
  84. GRB 060923: Swift detection of a burst
  85. Swift detection of IGR J17497-2821 (trigger 230504)
  86. GRB 060919: Swift detection of a burst
  87. GRB 060912A: VLA Observation
  88. GRB 060912: Swift detection of a burst with an optical afterglow
  89. VLA observations of GRB 060908
  90. GRB 060908: PROMPT Detection of a Bright Counterpart
  91. GRB 060908: Swift detection of a burst with a bright optical counterpart
  92. GRB 060906: KAIT observations
  93. GRB 060906: Swift detection of a probable burst
  94. GRB 060904A: Swift-XRT refined analysis
  95. GRB060904B: Watcher observations
  96. GRB 060904B: Swift detection of a burst with optical counterpart
  97. GRB 060904B: ROTSE-III Detection of Optical Counterpart
  98. GRB 060904: Swift detection of a bright burst
  99. GRB 060901: SMARTS optical/IR observations update
  100. GRB 060901: SMARTS optical/IR observations

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