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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').
Advanced Search

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"

28048 results found.

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

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