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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"

28058 results found.

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

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