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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"

18507 results found.

  1. GRB 050813: Swift XRT afterglow localization
  2. GRB 050813: Possible Short Swift-BAT GRB
  3. GRB050813 (Swift 150139): P60 Observations
  4. Swift-BAT trigger 150131 is not a GRB
  5. GRB050805b: CrAO optical limit
  6. GRB050805a : Null detection report
  7. Swift-BAT trigger 149118 is very likely not a GRB
  8. Retraction of Swift Trigger 149131 (GRB 050805B)
  9. GRB 050805b: OHP optical limits
  10. GRB 050805b: TAROT optical limits
  11. GRB050805b: MASTER optical observations
  12. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  13. GRB050805a: MASTER optical candidat
  14. Swift-BAT trigger 149118 is probably not a GRB
  15. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  16. GRB 050803: Swift-BAT refined analysis
  17. GRB050803: MASTER further analys
  18. GRB 050803: early Swift XRT analysis results
  19. GRB 050803: TAROT optical limits
  20. GRB050803: MASTER optical observations
  21. GRB050803: Swift-BAT detection of a very long burst
  22. GCN GRB observation 050713A
  23. GRB 050802: Swift/UVOT optical and UV detections
  24. GRB050802 radio non-detection
  25. GRB 050730: OHP optical observations
  26. GRB 050802: early Swift XRT analysis results
  27. GRB 050802: Swift/UVOT observations
  28. GRB 050802: Swift-BAT refined analysis
  29. GRB 050802: XRT position
  30. GRB 050802: Swift Gamma-ray Burst
  31. GRB050801: Swift/UVOT Optical and UV detections
  32. GCN 050801: early Swift XRT analysis results
  33. GRB 050801: Swift-BAT refined analysis
  34. GRB 050801, afterglow observations
  35. GRB 050730, corrected photometry and break?
  36. GRB 050801: ROTSE-III Early Afterglow Break
  37. GRB050801: Swift-BAT detection of a burst
  38. GRB050801: GCN XRT position is incorrect
  39. GRB 050801: ROTSE-III Detection of Possible Counterpart
  40. GRB 050730: XRT refined analysis
  41. GRB 050730: early TAROT optical observations
  42. Swift/UVOT photometry of GRB050730
  43. GRB050730: Refined BAT analysis of the Swift-BAT burst
  44. GRB 050730: Swift XRT afterglow observations
  45. GRB 050730 XMM-Newton observation
  46. GRB050730, afterglow observations
  47. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  48. GRB050730: Liverpool Telescope optical observations
  49. GRB 050730, optical candidate
  50. GRB050730: Swift-BAT detection of a weak burst
  51. GRB 050713A: Swift XRT extended light curve
  52. GRB050726: Swift UVOT observations
  53. GRB 050724: Chandra Observations of the X-ray Afterglow
  54. GRB050713: analysis of the XMM-Newton observation
  55. Swift-BAT trigger 147918 is not a real GRB
  56. GRB 050727: RTT150 optical observations
  57. GRB050727: KAIT optical limit
  58. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  59. GRB 050726: early Swift XRT analysis results
  60. GRB050726: Swift-BAT detection of a weak burst
  61. GRB 050724: SWIFT XRT refined position
  62. GRB 050724: optical and near-IR observations
  63. GRB 050724: Swift/UVOT Upper Limit
  64. GRB 050724: early Swift XRT analysis results
  65. GRB050724: Refined analysis of the Swift-BAT possible short burst
  66. GRB050724: a short-burst detected by Swift
  67. Swift-BAT trigger 147325 is not due to a real GRB
  68. GRB050723: XRT distributed coordinates are not related to the burst
  69. GRB 050721A: Swift-BAT refined analysis
  70. GRB 050721A: Early Swift XRT analysis results
  71. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  72. GRB 050721a: Optical Observations
  73. GRB050721A: Swift-BAT detection of a weak burst
  74. GRB 050714a: Refined XRT analysis and afterglow confirmation
  75. Swift-BAT trigger 146731 is not a real GRB
  76. Swift-BAT detection of a possible GRB
  77. GRB050717
  78. Konus-Wind observation of GRB 050717
  79. Swift/UVOT Observations of GRB 050717
  80. GRB 050717: Swift-BAT refined analysis
  81. GRB 050717: Refined XRT analysis.
  82. GRB050712: optical limits
  83. GRB050717: Swift XRT position
  84. Swift detection of GRB 050717
  85. GRB 050716 - UKIRT identification of candidate afterglow
  86. Swift UVOT Observations of GRB 050716
  87. GRB 050716: Refined XRT analysis.
  88. GRB050716: Refined analysis of the Swift-BAT burst
  89. GRB050716, optical observation
  90. GRB050716: Faulkes North Telescope observation
  91. GRB050716: Correction to sign in XRT coordinate
  92. Swift/BAT detection of GRB 050716
  93. GRB050715: Refined analysis of the Swift-BAT burst
  94. GRB 050715: Swift-BAT detection
  95. Swift UVOT Observations of GRB 050714B
  96. Konus-Wind observation of GRB 050713A
  97. GRB 050714B: refined XRT analysis
  98. GRB050714B: Refined analysis of the Swift-BAT burst
  99. Swift detection of a long transient (GRB 050714B?)
  100. GRB 050714: Swift XRT afterglow position

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