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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"

19592 results found.

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