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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"

19596 results found.

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

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