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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"

18540 results found.

  1. GRB 050820a: NIR Observations by WIRO
  2. GRB 050820B: Swift XRT position
  3. GRB050820B: Refined analysis of the Swift-BAT burst
  4. GRB050820B: BAT-Swift detection of a bright GRB
  5. Swift/UVOT photometry of GRB050820
  6. GRB050820: refined XRT analysis
  7. GRB 050820: Early RAPTOR detections
  8. GRB 050820 Swift-BAT refined analysis
  9. GRB050819: refined XRT analysis
  10. GRB 050820: Swift detection of a GRB
  11. GRB050820: Optical afterglow from P60
  12. GRB 050819 Swift-BAT refined analysis
  13. GRB050819: Swift XRT position
  14. GRB050819: Swift-BAT detection of a weak burst
  15. Swift-BAT trigger 150993 is not a GRB
  16. Swift Trigger 150823 is HETE J1900.1-2455
  17. GRB050817: Swift-BAT Detection of a burst
  18. GRB050815: Optical afterglow detection by Swift UVOT
  19. GRB050815: XRT refined analysis
  20. GRB050815: Refined analysis of the Swift-BAT burst
  21. GRB 050815: ROTSE-III Optical Limits
  22. GRB050815: Swift XRT afterglow localization
  23. GRB050815: Swift-BAT detection of a burst
  24. GRB050814: P60 Optical Afterglow Candidate
  25. GRB 050814: XRT refined analysis
  26. GRB050814: SWIFT/UVOT observation
  27. GRB050814: Refined analysis of the Swift-BAT burst
  28. GRB 050814: Swift XRT Afterglow Localization
  29. GRB 050814: Swift detection of a burst
  30. GRB050813, SDSS pre-burst observations
  31. GRB 050813: KAIT optical limit
  32. GRB 050813: Swift-BAT refined analysis
  33. GRB050813: SWIFT/UVOT observation
  34. GRB 050813: Swift XRT afterglow localization
  35. GRB 050813: Possible Short Swift-BAT GRB
  36. GRB050813 (Swift 150139): P60 Observations
  37. Swift-BAT trigger 150131 is not a GRB
  38. GRB050805b: CrAO optical limit
  39. GRB050805a : Null detection report
  40. Swift-BAT trigger 149118 is very likely not a GRB
  41. Retraction of Swift Trigger 149131 (GRB 050805B)
  42. GRB 050805b: OHP optical limits
  43. GRB 050805b: TAROT optical limits
  44. GRB050805b: MASTER optical observations
  45. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  46. GRB050805a: MASTER optical candidat
  47. Swift-BAT trigger 149118 is probably not a GRB
  48. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  49. GRB 050803: Swift-BAT refined analysis
  50. GRB050803: MASTER further analys
  51. GRB 050803: early Swift XRT analysis results
  52. GRB 050803: TAROT optical limits
  53. GRB050803: MASTER optical observations
  54. GRB050803: Swift-BAT detection of a very long burst
  55. GCN GRB observation 050713A
  56. GRB 050802: Swift/UVOT optical and UV detections
  57. GRB050802 radio non-detection
  58. GRB 050730: OHP optical observations
  59. GRB 050802: early Swift XRT analysis results
  60. GRB 050802: Swift/UVOT observations
  61. GRB 050802: Swift-BAT refined analysis
  62. GRB 050802: XRT position
  63. GRB 050802: Swift Gamma-ray Burst
  64. GRB050801: Swift/UVOT Optical and UV detections
  65. GCN 050801: early Swift XRT analysis results
  66. GRB 050801: Swift-BAT refined analysis
  67. GRB 050801, afterglow observations
  68. GRB 050730, corrected photometry and break?
  69. GRB 050801: ROTSE-III Early Afterglow Break
  70. GRB050801: Swift-BAT detection of a burst
  71. GRB050801: GCN XRT position is incorrect
  72. GRB 050801: ROTSE-III Detection of Possible Counterpart
  73. GRB 050730: XRT refined analysis
  74. GRB 050730: early TAROT optical observations
  75. Swift/UVOT photometry of GRB050730
  76. GRB050730: Refined BAT analysis of the Swift-BAT burst
  77. GRB 050730: Swift XRT afterglow observations
  78. GRB 050730 XMM-Newton observation
  79. GRB050730, afterglow observations
  80. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  81. GRB050730: Liverpool Telescope optical observations
  82. GRB 050730, optical candidate
  83. GRB050730: Swift-BAT detection of a weak burst
  84. GRB 050713A: Swift XRT extended light curve
  85. GRB050726: Swift UVOT observations
  86. GRB 050724: Chandra Observations of the X-ray Afterglow
  87. GRB050713: analysis of the XMM-Newton observation
  88. Swift-BAT trigger 147918 is not a real GRB
  89. GRB 050727: RTT150 optical observations
  90. GRB050727: KAIT optical limit
  91. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  92. GRB 050726: early Swift XRT analysis results
  93. GRB050726: Swift-BAT detection of a weak burst
  94. GRB 050724: SWIFT XRT refined position
  95. GRB 050724: optical and near-IR observations
  96. GRB 050724: Swift/UVOT Upper Limit
  97. GRB 050724: early Swift XRT analysis results
  98. GRB050724: Refined analysis of the Swift-BAT possible short burst
  99. GRB050724: a short-burst detected by Swift
  100. Swift-BAT trigger 147325 is not due to a real GRB

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