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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"

18397 results found.

  1. GRB050713B: Faulkes North Telescope observation
  2. RBO RI observations of GRB 050713A
  3. GRB 050713B
  4. GRB050713: Liverpool Telescope prompt observations
  5. GRB050709: Candidate X-ray Afterglow from Chandra
  6. GRB 050713, R-band observations at NOT
  7. GRB 050713: Swift detection of Bright Burst
  8. GRB 050713A: ROTSE-III Optical Limits
  9. GRB050712: XRT refined analysis
  10. GRB 050709: Swift UVOT and XRT observations
  11. GRB 050712: Swift-BAT Refined Analysis
  12. GRB050712: UVOT candidate optical counterpart
  13. GRB 050712: Swift XRT afterglow position
  14. GRB 050712: Swift detection of a weak burst
  15. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  16. GRB 050626: Swift XRT observations
  17. GRB 050701
  18. GRB 050701, optical observations
  19. GRB 050701: Refined XRT analysis
  20. Swift UVOT observations of GRB 050701
  21. GRB050701: Swift-BAT Refined analysis
  22. GRB 050701: Swift XRT afterglow position
  23. Swift trigger 143708 is really GRB 050701
  24. GRB 050525A: Swift Late-Time Decay Rate
  25. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  26. GRB 050416(a): Host Galaxy Redshift Determination
  27. Swift/UVOT observations of GRB050607
  28. GRB 050607: RAPTOR-S Early Optical Limits
  29. GRB050607: KAIT optical limits
  30. GRB 050607: MDM Observations
  31. GRB050607,optical observation
  32. GRB 050607 - XRT refined data analysis
  33. GRB050607 optical limit by "Pi of the Sky"
  34. GRB050607: Swift Detection of a long GRB
  35. GRB 050603 - XRT data analysis of the first day
  36. Konus-Wind observation of GRB 050603
  37. GRB 050603: Analysis of UVOT data
  38. GRB050603: Fading Afterglow observed by Swift UVOT
  39. GRB 050603: Swift XRT Position
  40. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  41. Swift/BAT Detection of GRB050603
  42. GRB 050408: jet break in the XRT light curve
  43. GRB050528, XRT observations
  44. Correction to GCN Circ 3502 on GRB 050528
  45. Swift-BAT GRB 050528: a soft burst
  46. Update on Swift-BAT GRB 050528 (Trigger 130679)
  47. Possible GRB050528: no candidate from Liverpool Telescope
  48. Swift-BAT detection of possible GRB 050528
  49. GRB 050509b: refined XRT/Chandra afterglow position analysis
  50. GRB050525a: optical upper limits
  51. GRB 050525B: Swift-BAT observations
  52. GRB050525A,optical observation
  53. GRB050525: Super-LOTIS observations
  54. GRB 050525, spectral lag pseudo-redshift
  55. GRB050306: optical afterglow not confirmed
  56. GRB 050525A: BOOTES simultaneous optical observations
  57. GRB 050525A: Swift-BAT refined analysis
  58. Swift/UVOT UV and optical detections of GRB 050525
  59. Konus-Wind observation of GRB 050525
  60. GRB 050525: TAROT observations of the early afterglow
  61. INTEGRAL detection of GRB 050525
  62. GRB 050525: Optical observation
  63. GRB050525: ROTSE-III Refined Analysis
  64. GRB 050525 - Very Bright, Not Short
  65. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  66. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  67. XRF 050522: Swift XRT refined analysis
  68. Swift/UVOT observation of XRF 050522
  69. GRB 050509A: Further I-band imaging
  70. RBO Observations of GRB050522
  71. XRF 050522: Swift XRT observation
  72. GRB 050520: VLT/ULTRACAM observations
  73. Swift UVOT Observations of GRB 050520
  74. GRB 050520: Swift XRT refined analysis
  75. XRF050509C: Chandra Afterglow Detection
  76. XRF 050509c: Swift XRT Upper Limit
  77. RBO Observations of GRB050520
  78. GRB 050520: TAROT optical limit
  79. GRB 050520: Swift XRT position
  80. No Swift-BAT Lightcurves in real-time for next 3 weeks
  81. Swift-BAT trigger 122203 is not a real GRB
  82. GRB 050504: Swift XRT afterglow candidate has faded
  83. GRB 050509B: Subaru Optical Observations
  84. GRB050502b: Early Observation
  85. Refined Chandra analysis of GRB 050509b
  86. GRB050509b, SDSS pre-burst observations
  87. Chandra observation of GRB 050509b
  88. GRB 050509b: RAPTOR deep, early limits.
  89. GRB050509B: Optical/Infared observations
  90. GRB 050509b: Swift/UVOT follow-up measurements
  91. GRB 050509b Milagro GeV/TeV Observations
  92. GRB050509B: Optical observations at the Very Large Telescope
  93. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  94. GRB 050509a: Swift-BAT refined analysis
  95. GRB 050509B: WSRT Radio Observations
  96. GRB 050505: SARA Observations
  97. Swift UVOT Follow-up Observations of GRB 050509B
  98. GRB 050509B, Optical Observations
  99. GRB 050509B: Swift/XRT refined analysis
  100. GRB050509a: Swift UVOT observations

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