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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18719 results found.

  1. GRB 050904: BAT refined analysis of partial data set
  2. GRB050904: P60 Observations
  3. GRB 050904: TAROT optical limits
  4. GRB050904: Swift-BAT detection of a probable burst
  5. Swift-BAT triggers 153461-153465 are not GRBs
  6. Retraction of Swift-BAT trigger #153355
  7. GRB 050824: MDM Observations
  8. GRB 050827: Swift XRT preliminary analysis results
  9. Swift Trigger #152652 is not a GRB
  10. GRB050827: Swift/UVOT upper limits
  11. GRB 050827: Optical Limit
  12. GRB 050827: XRT possible afterglow detection
  13. GRB050827: RTT150 optical observations
  14. GRB 050827: Swift-BAT refined analysis
  15. GRB050827: Swift-BAT detection of a burst
  16. GRB 050826: Optical Candidate
  17. GRB050824, HETE-2 Observation
  18. GRB 050826: Swift XRT preliminary analysis results
  19. GRB 050826: BAT refined analysis
  20. GRB050826: Swift/UVOT early upper limits
  21. GRB050824: First 2 hours of power low optical decay?
  22. GRB 050826: Swift XRT position
  23. GRB050826: Swift-BAT detection of a long burst
  24. GRB050824: MASTER final analysis of the OT observations
  25. Possible GRB050825:MASTER optical observations
  26. Swift-BAT trigger 152038 is definitely not a GRB
  27. GRB050824: CORRECTION to UVOT observing times
  28. Swift-BAT trigger 152038 is probably not a GRB
  29. GRB050824: Swift/UVOT detection of fading afterglow
  30. GRB050824: decay of the XRT light curve and updated X-ray spectrum
  31. GRB050824, I-band imaging
  32. GRB 050822: refined XRT analysis
  33. GRB 050824: XRT refined analysis and possible afterglow detection
  34. GRB 050824: BAT refined analysis of a soft weak burst
  35. GRB050824: MASTER:OT decay
  36. GRB050824: MASTER observation OT
  37. GRB050805a: MASTER optical candidat
  38. GRB 050824: ROTSE-III Optical Limits
  39. GRB050824: Swift-BAT detection of a burst
  40. GRB050822: Swift/UVOT upper limits
  41. GRB 050820A BAT observations of second, larger episode of emission
  42. GRB 050822: Swift-BAT refined analysis
  43. GRB 050820a - corrections to GCN 3846
  44. Swift/UVOT UV Photometry of GRB 050820B
  45. GRB 050822: ROTSE-III Prompt Optical Limits
  46. GRB 050822: Swift detection of a long burst
  47. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  48. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  49. GRB050820a BVRcIc field photometry
  50. GRB050820B XMM-Newton observation
  51. GRB 050820a: NIR Observations by WIRO
  52. GRB 050820B: Swift XRT position
  53. GRB050820B: Refined analysis of the Swift-BAT burst
  54. GRB050820B: BAT-Swift detection of a bright GRB
  55. Swift/UVOT photometry of GRB050820
  56. GRB050820: refined XRT analysis
  57. GRB 050820: Early RAPTOR detections
  58. GRB 050820 Swift-BAT refined analysis
  59. GRB050819: refined XRT analysis
  60. GRB 050820: Swift detection of a GRB
  61. GRB050820: Optical afterglow from P60
  62. GRB 050819 Swift-BAT refined analysis
  63. GRB050819: Swift XRT position
  64. GRB050819: Swift-BAT detection of a weak burst
  65. Swift-BAT trigger 150993 is not a GRB
  66. Swift Trigger 150823 is HETE J1900.1-2455
  67. GRB050817: Swift-BAT Detection of a burst
  68. GRB050815: Optical afterglow detection by Swift UVOT
  69. GRB050815: XRT refined analysis
  70. GRB050815: Refined analysis of the Swift-BAT burst
  71. GRB 050815: ROTSE-III Optical Limits
  72. GRB050815: Swift XRT afterglow localization
  73. GRB050815: Swift-BAT detection of a burst
  74. GRB050814: P60 Optical Afterglow Candidate
  75. GRB 050814: XRT refined analysis
  76. GRB050814: SWIFT/UVOT observation
  77. GRB050814: Refined analysis of the Swift-BAT burst
  78. GRB 050814: Swift XRT Afterglow Localization
  79. GRB 050814: Swift detection of a burst
  80. GRB050813, SDSS pre-burst observations
  81. GRB 050813: KAIT optical limit
  82. GRB 050813: Swift-BAT refined analysis
  83. GRB050813: SWIFT/UVOT observation
  84. GRB 050813: Swift XRT afterglow localization
  85. GRB 050813: Possible Short Swift-BAT GRB
  86. GRB050813 (Swift 150139): P60 Observations
  87. Swift-BAT trigger 150131 is not a GRB
  88. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  89. Detection of an intermediate burst from SGR 1806-20 on August 8
  90. GRB050805b: CrAO optical limit
  91. GRB050805a : Null detection report
  92. Swift-BAT trigger 149118 is very likely not a GRB
  93. Retraction of Swift Trigger 149131 (GRB 050805B)
  94. GRB 050805b: OHP optical limits
  95. GRB 050805b: TAROT optical limits
  96. GRB050805b: MASTER optical observations
  97. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  98. GRB050805a: MASTER optical candidat
  99. Swift-BAT trigger 149118 is probably not a GRB
  100. GRB050803: Optical/UV Upper Limits from Swift-UVOT

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