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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"

18506 results found.

  1. GRB 050713A: RAPTOR detection of early optical emission
  2. GRB050713B :Swift/UVOT observations
  3. GRB050713b: XRT refined analysis
  4. GRB 050713B: Swift-BAT Refined Analysis
  5. Swift-BAT Trigger 145729 is not a GRB
  6. GRB 050713A: Swift/UVOT observation
  7. GRB 050713A : Swift-BAT Refined Analysis
  8. GRB050712: Swift UVOT Observation of Afterglow Emission
  9. GRB 050713A XMM-Newton observation
  10. GRB050713B: Faulkes North Telescope observation
  11. RBO RI observations of GRB 050713A
  12. GRB 050713B
  13. GRB050713: Liverpool Telescope prompt observations
  14. GRB050709: Candidate X-ray Afterglow from Chandra
  15. GRB 050713, R-band observations at NOT
  16. GRB 050713: Swift detection of Bright Burst
  17. GRB 050713A: ROTSE-III Optical Limits
  18. GRB050712: XRT refined analysis
  19. GRB 050709: Swift UVOT and XRT observations
  20. GRB 050712: Swift-BAT Refined Analysis
  21. GRB050712: UVOT candidate optical counterpart
  22. GRB 050712: Swift XRT afterglow position
  23. GRB 050712: Swift detection of a weak burst
  24. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  25. GRB 050626: Swift XRT observations
  26. GRB 050701
  27. GRB 050701, optical observations
  28. GRB 050701: Refined XRT analysis
  29. Swift UVOT observations of GRB 050701
  30. GRB050701: Swift-BAT Refined analysis
  31. GRB 050701: Swift XRT afterglow position
  32. Swift trigger 143708 is really GRB 050701
  33. GRB 050525A: Swift Late-Time Decay Rate
  34. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  35. GRB 050416(a): Host Galaxy Redshift Determination
  36. Swift/UVOT observations of GRB050607
  37. GRB 050607: RAPTOR-S Early Optical Limits
  38. GRB050607: KAIT optical limits
  39. GRB 050607: MDM Observations
  40. GRB050607,optical observation
  41. GRB 050607 - XRT refined data analysis
  42. GRB050607 optical limit by "Pi of the Sky"
  43. GRB050607: Swift Detection of a long GRB
  44. GRB 050603 - XRT data analysis of the first day
  45. Konus-Wind observation of GRB 050603
  46. GRB 050603: Analysis of UVOT data
  47. GRB050603: Fading Afterglow observed by Swift UVOT
  48. GRB 050603: Swift XRT Position
  49. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  50. Swift/BAT Detection of GRB050603
  51. GRB 050408: jet break in the XRT light curve
  52. GRB050528, XRT observations
  53. Correction to GCN Circ 3502 on GRB 050528
  54. Swift-BAT GRB 050528: a soft burst
  55. Update on Swift-BAT GRB 050528 (Trigger 130679)
  56. Possible GRB050528: no candidate from Liverpool Telescope
  57. Swift-BAT detection of possible GRB 050528
  58. GRB 050509b: refined XRT/Chandra afterglow position analysis
  59. GRB050525a: optical upper limits
  60. GRB 050525B: Swift-BAT observations
  61. GRB050525A,optical observation
  62. GRB050525: Super-LOTIS observations
  63. GRB 050525, spectral lag pseudo-redshift
  64. GRB050306: optical afterglow not confirmed
  65. GRB 050525A: BOOTES simultaneous optical observations
  66. GRB 050525A: Swift-BAT refined analysis
  67. Swift/UVOT UV and optical detections of GRB 050525
  68. Konus-Wind observation of GRB 050525
  69. GRB 050525: TAROT observations of the early afterglow
  70. INTEGRAL detection of GRB 050525
  71. GRB 050525: Optical observation
  72. GRB050525: ROTSE-III Refined Analysis
  73. GRB 050525 - Very Bright, Not Short
  74. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  75. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  76. XRF 050522: Swift XRT refined analysis
  77. Swift/UVOT observation of XRF 050522
  78. GRB 050509A: Further I-band imaging
  79. RBO Observations of GRB050522
  80. XRF 050522: Swift XRT observation
  81. GRB 050520: VLT/ULTRACAM observations
  82. Swift UVOT Observations of GRB 050520
  83. GRB 050520: Swift XRT refined analysis
  84. XRF050509C: Chandra Afterglow Detection
  85. XRF 050509c: Swift XRT Upper Limit
  86. RBO Observations of GRB050520
  87. GRB 050520: TAROT optical limit
  88. GRB 050520: Swift XRT position
  89. No Swift-BAT Lightcurves in real-time for next 3 weeks
  90. Swift-BAT trigger 122203 is not a real GRB
  91. GRB 050504: Swift XRT afterglow candidate has faded
  92. GRB 050509B: Subaru Optical Observations
  93. GRB050502b: Early Observation
  94. Refined Chandra analysis of GRB 050509b
  95. GRB050509b, SDSS pre-burst observations
  96. Chandra observation of GRB 050509b
  97. GRB 050509b: RAPTOR deep, early limits.
  98. GRB050509B: Optical/Infared observations
  99. GRB 050509b: Swift/UVOT follow-up measurements
  100. GRB 050509b Milagro GeV/TeV Observations

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