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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"

28056 results found.

  1. GRB050726: Swift-BAT detection of a weak burst
  2. GRB 050724: Optical Variability in Nearby Galaxy
  3. GRB 050724: J-band observations
  4. GRB 050724: GMOS Imaging and Spectroscopy
  5. GRB050724: Radio Observation
  6. GRB 050724: Optical imaging/astrometry
  7. GRB 050724: Swift/UVOT Upper Limit
  8. GRB050724: Refined analysis of the Swift-BAT possible short burst
  9. GRB 050724: possible host galaxy in DSS
  10. GRB 050721A: Swift-BAT refined analysis
  11. GRB 050721A: Early Swift XRT analysis results
  12. GRB050721A: optical decay
  13. GRB 050721: optical afterglow confirmed
  14. GRB 050709: Refined Spectral and Temporal Properties
  15. GRB050714b: Radio Observation
  16. GRB050712: Radio Observations
  17. GRB050713a: Radio Observation
  18. GRB 050712, Tautenburg optical afterglow observations
  19. Swift-BAT detection of a possible GRB
  20. GRB 050714B: VLT R-band observations
  21. GRB 050717: Additional LCO observations
  22. GRB 050716; J-band observations
  23. GRB 050717: LCO near-IR observations
  24. Swift/UVOT Observations of GRB 050717
  25. GRB 050717: Swift-BAT refined analysis
  26. GRB050717: Swift XRT position
  27. Swift detection of GRB 050717
  28. Swift UVOT Observations of GRB 050716
  29. GRB 050716: Refined XRT analysis.
  30. GRB050716: Refined analysis of the Swift-BAT burst
  31. GRB 050716: Lulin B and R band optical observations
  32. GRB050716, optical observation
  33. GRB050716: Faulkes North Telescope observation
  34. GRB050715: Refined analysis of the Swift-BAT burst
  35. GRB 050715: Swift-BAT detection
  36. GRB 050713b: RTT150 optical observations
  37. GRB050714B: Refined analysis of the Swift-BAT burst
  38. GRB 050714B: optical afterglow
  39. GRB 050714, R-band candidate
  40. GRB 050714, optical observations
  41. GRB 050713A: XRT refined analysis
  42. GRB 050713A: RAPTOR detection of early optical emission
  43. GRB050713B :Swift/UVOT observations
  44. GRB050713b: XRT refined analysis
  45. GRB050712: TNG R-band observations
  46. GRB 050713B: Swift-BAT Refined Analysis
  47. GRB 050713A: Swift/UVOT observation
  48. GRB 050713A : Swift-BAT Refined Analysis
  49. GRB050712: Swift UVOT Observation of Afterglow Emission
  50. GRB 050713A : Lulin R-band observation
  51. GRB 050713A XMM-Newton observation
  52. GRB 050713b : Lulin R-band observations
  53. GRB050713B: Faulkes North Telescope observation
  54. RBO RI observations of GRB 050713A
  55. GRB 050713B
  56. GRB050709 : Chandra source optical counterpart
  57. GRB050713: Liverpool Telescope prompt observations
  58. GRB 050712, optical observations
  59. GRB050709: Candidate X-ray Afterglow from Chandra
  60. GRB050713: possible I-band afterglow
  61. GRB050712: XRT refined analysis
  62. GRB050709: Radio Observations
  63. GRB 050709: Swift UVOT and XRT observations
  64. GRB 050712: Swift-BAT Refined Analysis
  65. GRB050712: UVOT candidate optical counterpart
  66. GRB 050709: LCO40 Observations
  67. GRB050709, optical observations
  68. PROMPT Rc Observations of GRB 050709
  69. GRB 050525a: PROMPT VRcIc Detections
  70. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  71. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  72. GRB 050626: Swift XRT observations
  73. GRB 050408: ARC 3.5-meter NIR Observations
  74. GRB 050701: Refined XRT analysis
  75. Swift UVOT observations of GRB 050701
  76. GRB050701: Swift-BAT Refined analysis
  77. Swift trigger 143708 is really GRB 050701
  78. GRB 050607, radio observations
  79. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  80. GRB050525a: HST Observations
  81. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  82. XRF 050509c: Optical monitoring
  83. Konus-Wind observation of an intermediate burst from SGR 1806-20
  84. XRF050509c: Radio Detection
  85. GRB 050607 optical decay
  86. GRB050607: refined analysis of prompt REM observations
  87. GRB 050607: PROMPT VRcIc Observations
  88. GRB 050607: Optical decay and spectral slope
  89. GRB050607,optical observation
  90. Optical Afterglow of GRB 050607
  91. GRB050607: Swift Detection of a long GRB
  92. GRB050607: prompt REM observations
  93. Limits on a SN in the field of GRB 050509b
  94. GRB 050603 - XRT data analysis of the first day
  95. GRB050603, submillimetre observations
  96. GRB050603: Radio Detection
  97. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  98. GRB 050603: INTEGRAL shows it is not a short GRB
  99. GRB 050525a, infrared observations
  100. GRB050528, XRT observations

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