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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

24951 results found.

  1. GRB 050724: Optical imaging/astrometry
  2. GRB 050724: Swift/UVOT Upper Limit
  3. GRB050724: Refined analysis of the Swift-BAT possible short burst
  4. GRB 050724: possible host galaxy in DSS
  5. GRB 050721A: Swift-BAT refined analysis
  6. GRB 050721A: Early Swift XRT analysis results
  7. GRB050721A: optical decay
  8. GRB 050721: optical afterglow confirmed
  9. GRB 050709: Refined Spectral and Temporal Properties
  10. GRB050714b: Radio Observation
  11. GRB050712: Radio Observations
  12. GRB050713a: Radio Observation
  13. GRB 050712, Tautenburg optical afterglow observations
  14. Swift-BAT detection of a possible GRB
  15. GRB 050714B: VLT R-band observations
  16. GRB 050717: Additional LCO observations
  17. GRB 050716; J-band observations
  18. GRB 050717: LCO near-IR observations
  19. Swift/UVOT Observations of GRB 050717
  20. GRB 050717: Swift-BAT refined analysis
  21. GRB050717: Swift XRT position
  22. Swift detection of GRB 050717
  23. Swift UVOT Observations of GRB 050716
  24. GRB 050716: Refined XRT analysis.
  25. GRB050716: Refined analysis of the Swift-BAT burst
  26. GRB 050716: Lulin B and R band optical observations
  27. GRB050716, optical observation
  28. GRB050716: Faulkes North Telescope observation
  29. GRB050715: Refined analysis of the Swift-BAT burst
  30. GRB 050715: Swift-BAT detection
  31. GRB 050713b: RTT150 optical observations
  32. GRB050714B: Refined analysis of the Swift-BAT burst
  33. GRB 050714B: optical afterglow
  34. GRB 050714, R-band candidate
  35. GRB 050714, optical observations
  36. GRB 050713A: XRT refined analysis
  37. GRB 050713A: RAPTOR detection of early optical emission
  38. GRB050713B :Swift/UVOT observations
  39. GRB050713b: XRT refined analysis
  40. GRB050712: TNG R-band observations
  41. GRB 050713B: Swift-BAT Refined Analysis
  42. GRB 050713A: Swift/UVOT observation
  43. GRB 050713A : Swift-BAT Refined Analysis
  44. GRB050712: Swift UVOT Observation of Afterglow Emission
  45. GRB 050713A : Lulin R-band observation
  46. GRB 050713A XMM-Newton observation
  47. GRB 050713b : Lulin R-band observations
  48. GRB050713B: Faulkes North Telescope observation
  49. RBO RI observations of GRB 050713A
  50. GRB 050713B
  51. GRB050709 : Chandra source optical counterpart
  52. GRB050713: Liverpool Telescope prompt observations
  53. GRB 050712, optical observations
  54. GRB050709: Candidate X-ray Afterglow from Chandra
  55. GRB050713: possible I-band afterglow
  56. GRB050712: XRT refined analysis
  57. GRB050709: Radio Observations
  58. GRB 050709: Swift UVOT and XRT observations
  59. GRB 050712: Swift-BAT Refined Analysis
  60. GRB050712: UVOT candidate optical counterpart
  61. GRB 050709: LCO40 Observations
  62. GRB050709, optical observations
  63. PROMPT Rc Observations of GRB 050709
  64. GRB 050525a: PROMPT VRcIc Detections
  65. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  66. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  67. GRB 050626: Swift XRT observations
  68. GRB 050408: ARC 3.5-meter NIR Observations
  69. GRB 050701: Refined XRT analysis
  70. Swift UVOT observations of GRB 050701
  71. GRB050701: Swift-BAT Refined analysis
  72. Swift trigger 143708 is really GRB 050701
  73. GRB 050607, radio observations
  74. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  75. GRB050525a: HST Observations
  76. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  77. XRF 050509c: Optical monitoring
  78. Konus-Wind observation of an intermediate burst from SGR 1806-20
  79. XRF050509c: Radio Detection
  80. GRB 050607 optical decay
  81. GRB050607: refined analysis of prompt REM observations
  82. GRB 050607: PROMPT VRcIc Observations
  83. GRB 050607: Optical decay and spectral slope
  84. GRB050607,optical observation
  85. Optical Afterglow of GRB 050607
  86. GRB050607: Swift Detection of a long GRB
  87. GRB050607: prompt REM observations
  88. Limits on a SN in the field of GRB 050509b
  89. GRB 050603 - XRT data analysis of the first day
  90. GRB050603, submillimetre observations
  91. GRB050603: Radio Detection
  92. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  93. GRB 050603: INTEGRAL shows it is not a short GRB
  94. GRB 050525a, infrared observations
  95. GRB050528, XRT observations
  96. GRB050528: updated Liverpool Telescope limits
  97. Swift-BAT GRB 050528: a soft burst
  98. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  99. Possible GRB050528: no candidate from Liverpool Telescope
  100. GRB050525a: Radio Observations

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