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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 050820: Early RAPTOR detections
  2. GRB 050820 Swift-BAT refined analysis
  3. GRB050819: refined XRT analysis
  4. GRB 050820: Swift detection of a GRB
  5. GRB050820: Optical afterglow from P60
  6. GRB 050819 Swift-BAT refined analysis
  7. GRB050819: Swift XRT position
  8. GRB050819: Swift-BAT detection of a weak burst
  9. Swift-BAT trigger 150993 is not a GRB
  10. Swift Trigger 150823 is HETE J1900.1-2455
  11. GRB050817: Swift-BAT Detection of a burst
  12. GRB050815: Optical afterglow detection by Swift UVOT
  13. GRB050815: XRT refined analysis
  14. GRB050815: Refined analysis of the Swift-BAT burst
  15. GRB 050815: ROTSE-III Optical Limits
  16. GRB050815: Swift XRT afterglow localization
  17. GRB050815: Swift-BAT detection of a burst
  18. GRB050814: P60 Optical Afterglow Candidate
  19. GRB 050814: XRT refined analysis
  20. GRB050814: SWIFT/UVOT observation
  21. GRB050814: Refined analysis of the Swift-BAT burst
  22. GRB 050814: Swift XRT Afterglow Localization
  23. GRB 050814: Swift detection of a burst
  24. GRB050813, SDSS pre-burst observations
  25. GRB 050813: KAIT optical limit
  26. GRB 050813: Swift-BAT refined analysis
  27. GRB050813: SWIFT/UVOT observation
  28. GRB 050813: Swift XRT afterglow localization
  29. GRB 050813: Possible Short Swift-BAT GRB
  30. GRB050813 (Swift 150139): P60 Observations
  31. Swift-BAT trigger 150131 is not a GRB
  32. GRB050805b: CrAO optical limit
  33. GRB050805a : Null detection report
  34. Swift-BAT trigger 149118 is very likely not a GRB
  35. Retraction of Swift Trigger 149131 (GRB 050805B)
  36. GRB 050805b: OHP optical limits
  37. GRB 050805b: TAROT optical limits
  38. GRB050805b: MASTER optical observations
  39. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  40. GRB050805a: MASTER optical candidat
  41. Swift-BAT trigger 149118 is probably not a GRB
  42. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  43. GRB 050803: Swift-BAT refined analysis
  44. GRB050803: MASTER further analys
  45. GRB 050803: early Swift XRT analysis results
  46. GRB 050803: TAROT optical limits
  47. GRB050803: MASTER optical observations
  48. GRB050803: Swift-BAT detection of a very long burst
  49. GCN GRB observation 050713A
  50. GRB 050802: Swift/UVOT optical and UV detections
  51. GRB050802 radio non-detection
  52. GRB 050730: OHP optical observations
  53. GRB 050802: early Swift XRT analysis results
  54. GRB 050802: Swift/UVOT observations
  55. GRB 050802: Swift-BAT refined analysis
  56. GRB 050802: XRT position
  57. GRB 050802: Swift Gamma-ray Burst
  58. GRB050801: Swift/UVOT Optical and UV detections
  59. GCN 050801: early Swift XRT analysis results
  60. GRB 050801: Swift-BAT refined analysis
  61. GRB 050801, afterglow observations
  62. GRB 050730, corrected photometry and break?
  63. GRB 050801: ROTSE-III Early Afterglow Break
  64. GRB050801: Swift-BAT detection of a burst
  65. GRB050801: GCN XRT position is incorrect
  66. GRB 050801: ROTSE-III Detection of Possible Counterpart
  67. GRB 050730: XRT refined analysis
  68. GRB 050730: early TAROT optical observations
  69. Swift/UVOT photometry of GRB050730
  70. GRB050730: Refined BAT analysis of the Swift-BAT burst
  71. GRB 050730: Swift XRT afterglow observations
  72. GRB 050730 XMM-Newton observation
  73. GRB050730, afterglow observations
  74. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  75. GRB050730: Liverpool Telescope optical observations
  76. GRB 050730, optical candidate
  77. GRB050730: Swift-BAT detection of a weak burst
  78. GRB 050713A: Swift XRT extended light curve
  79. GRB050726: Swift UVOT observations
  80. GRB 050724: Chandra Observations of the X-ray Afterglow
  81. GRB050713: analysis of the XMM-Newton observation
  82. Swift-BAT trigger 147918 is not a real GRB
  83. GRB 050727: RTT150 optical observations
  84. GRB050727: KAIT optical limit
  85. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  86. GRB 050726: early Swift XRT analysis results
  87. GRB050726: Swift-BAT detection of a weak burst
  88. GRB 050724: SWIFT XRT refined position
  89. GRB 050724: optical and near-IR observations
  90. GRB 050724: Swift/UVOT Upper Limit
  91. GRB 050724: early Swift XRT analysis results
  92. GRB050724: Refined analysis of the Swift-BAT possible short burst
  93. GRB050724: a short-burst detected by Swift
  94. Swift-BAT trigger 147325 is not due to a real GRB
  95. GRB050723: XRT distributed coordinates are not related to the burst
  96. GRB 050721A: Swift-BAT refined analysis
  97. GRB 050721A: Early Swift XRT analysis results
  98. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  99. GRB 050721a: Optical Observations
  100. GRB050721A: Swift-BAT detection of a weak burst

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