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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.

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

18655 results found.

  1. GRB050824: MASTER observation OT
  2. GRB050805a: MASTER optical candidat
  3. GRB 050824: ROTSE-III Optical Limits
  4. GRB050824: Swift-BAT detection of a burst
  5. GRB050822: Swift/UVOT upper limits
  6. GRB 050820A BAT observations of second, larger episode of emission
  7. GRB 050822: Swift-BAT refined analysis
  8. GRB 050820a - corrections to GCN 3846
  9. Swift/UVOT UV Photometry of GRB 050820B
  10. GRB 050822: ROTSE-III Prompt Optical Limits
  11. GRB 050822: Swift detection of a long burst
  12. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  13. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  14. GRB050820a BVRcIc field photometry
  15. GRB050820B XMM-Newton observation
  16. GRB 050820a: NIR Observations by WIRO
  17. GRB 050820B: Swift XRT position
  18. GRB050820B: Refined analysis of the Swift-BAT burst
  19. GRB050820B: BAT-Swift detection of a bright GRB
  20. Swift/UVOT photometry of GRB050820
  21. GRB050820: refined XRT analysis
  22. GRB 050820: Early RAPTOR detections
  23. GRB 050820 Swift-BAT refined analysis
  24. GRB050819: refined XRT analysis
  25. GRB 050820: Swift detection of a GRB
  26. GRB050820: Optical afterglow from P60
  27. GRB 050819 Swift-BAT refined analysis
  28. GRB050819: Swift XRT position
  29. GRB050819: Swift-BAT detection of a weak burst
  30. Swift-BAT trigger 150993 is not a GRB
  31. Swift Trigger 150823 is HETE J1900.1-2455
  32. GRB050817: Swift-BAT Detection of a burst
  33. GRB050815: Optical afterglow detection by Swift UVOT
  34. GRB050815: XRT refined analysis
  35. GRB050815: Refined analysis of the Swift-BAT burst
  36. GRB 050815: ROTSE-III Optical Limits
  37. GRB050815: Swift XRT afterglow localization
  38. GRB050815: Swift-BAT detection of a burst
  39. GRB050814: P60 Optical Afterglow Candidate
  40. GRB 050814: XRT refined analysis
  41. GRB050814: SWIFT/UVOT observation
  42. GRB050814: Refined analysis of the Swift-BAT burst
  43. GRB 050814: Swift XRT Afterglow Localization
  44. GRB 050814: Swift detection of a burst
  45. GRB050813, SDSS pre-burst observations
  46. GRB 050813: KAIT optical limit
  47. GRB 050813: Swift-BAT refined analysis
  48. GRB050813: SWIFT/UVOT observation
  49. GRB 050813: Swift XRT afterglow localization
  50. GRB 050813: Possible Short Swift-BAT GRB
  51. GRB050813 (Swift 150139): P60 Observations
  52. Swift-BAT trigger 150131 is not a GRB
  53. GRB050805b: CrAO optical limit
  54. GRB050805a : Null detection report
  55. Swift-BAT trigger 149118 is very likely not a GRB
  56. Retraction of Swift Trigger 149131 (GRB 050805B)
  57. GRB 050805b: OHP optical limits
  58. GRB 050805b: TAROT optical limits
  59. GRB050805b: MASTER optical observations
  60. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  61. GRB050805a: MASTER optical candidat
  62. Swift-BAT trigger 149118 is probably not a GRB
  63. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  64. GRB 050803: Swift-BAT refined analysis
  65. GRB050803: MASTER further analys
  66. GRB 050803: early Swift XRT analysis results
  67. GRB 050803: TAROT optical limits
  68. GRB050803: MASTER optical observations
  69. GRB050803: Swift-BAT detection of a very long burst
  70. GCN GRB observation 050713A
  71. GRB 050802: Swift/UVOT optical and UV detections
  72. GRB050802 radio non-detection
  73. GRB 050730: OHP optical observations
  74. GRB 050802: early Swift XRT analysis results
  75. GRB 050802: Swift/UVOT observations
  76. GRB 050802: Swift-BAT refined analysis
  77. GRB 050802: XRT position
  78. GRB 050802: Swift Gamma-ray Burst
  79. GRB050801: Swift/UVOT Optical and UV detections
  80. GCN 050801: early Swift XRT analysis results
  81. GRB 050801: Swift-BAT refined analysis
  82. GRB 050801, afterglow observations
  83. GRB 050730, corrected photometry and break?
  84. GRB 050801: ROTSE-III Early Afterglow Break
  85. GRB050801: Swift-BAT detection of a burst
  86. GRB050801: GCN XRT position is incorrect
  87. GRB 050801: ROTSE-III Detection of Possible Counterpart
  88. GRB 050730: XRT refined analysis
  89. GRB 050730: early TAROT optical observations
  90. Swift/UVOT photometry of GRB050730
  91. GRB050730: Refined BAT analysis of the Swift-BAT burst
  92. GRB 050730: Swift XRT afterglow observations
  93. GRB 050730 XMM-Newton observation
  94. GRB050730, afterglow observations
  95. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  96. GRB050730: Liverpool Telescope optical observations
  97. GRB 050730, optical candidate
  98. GRB050730: Swift-BAT detection of a weak burst
  99. GRB 050713A: Swift XRT extended light curve
  100. GRB050726: Swift UVOT observations

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