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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"

24887 results found.

  1. GRB 050803: Keck Observations
  2. GRB 050803: Swift-BAT refined analysis
  3. GRB 050802.422: Fading of the afterglow and detection of the host
  4. GRB 050803: early Swift XRT analysis results
  5. GRB 050803: TAROT optical limits
  6. GCN GRB observation 050713A
  7. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  8. GRB050802 radio non-detection
  9. GRB 050730: OHP optical observations
  10. GRB 050802: early Swift XRT analysis results
  11. GRB 050802: Swift/UVOT observations
  12. GRB 050802: Swift-BAT refined analysis
  13. GRB050801: Optical photometry and decay index
  14. GRB 050802: Swift Gamma-ray Burst
  15. GRB050801: Swift/UVOT Optical and UV detections
  16. GRB 050730: Preliminary Analysis of MIKE Spectrum
  17. GCN 050801: early Swift XRT analysis results
  18. GRB 050801: Swift-BAT refined analysis
  19. GRB 050730: XRT refined analysis
  20. GRB 050730: early TAROT optical observations
  21. GRB 050730, spectra and optical photometry
  22. GRB050730: Refined BAT analysis of the Swift-BAT burst
  23. GRB 050730 XMM-Newton observation
  24. GRB050730: Swift-BAT detection of a weak burst
  25. GRB050713b: Maidanak optical observations
  26. GRB 050724: Secure Host Redshift from Keck
  27. GRB 050724: WHT optical observations
  28. GRB050713: analysis of the XMM-Newton observation
  29. Swift-BAT trigger 147918 is not a real GRB
  30. GRB050724: VLT observations of the variable source
  31. GRB050709: Second Epoch Chandra Observation
  32. GRB050726: Swift-BAT detection of a weak burst
  33. GRB 050724: Optical Variability in Nearby Galaxy
  34. GRB 050724: J-band observations
  35. GRB 050724: GMOS Imaging and Spectroscopy
  36. GRB050724: Radio Observation
  37. GRB 050724: Optical imaging/astrometry
  38. GRB 050724: Swift/UVOT Upper Limit
  39. GRB050724: Refined analysis of the Swift-BAT possible short burst
  40. GRB 050724: possible host galaxy in DSS
  41. GRB 050721A: Swift-BAT refined analysis
  42. GRB 050721A: Early Swift XRT analysis results
  43. GRB050721A: optical decay
  44. GRB 050721: optical afterglow confirmed
  45. GRB 050709: Refined Spectral and Temporal Properties
  46. GRB050714b: Radio Observation
  47. GRB050712: Radio Observations
  48. GRB050713a: Radio Observation
  49. GRB 050712, Tautenburg optical afterglow observations
  50. Swift-BAT detection of a possible GRB
  51. GRB 050714B: VLT R-band observations
  52. GRB 050717: Additional LCO observations
  53. GRB 050716; J-band observations
  54. GRB 050717: LCO near-IR observations
  55. Swift/UVOT Observations of GRB 050717
  56. GRB 050717: Swift-BAT refined analysis
  57. GRB050717: Swift XRT position
  58. Swift detection of GRB 050717
  59. Swift UVOT Observations of GRB 050716
  60. GRB 050716: Refined XRT analysis.
  61. GRB050716: Refined analysis of the Swift-BAT burst
  62. GRB 050716: Lulin B and R band optical observations
  63. GRB050716, optical observation
  64. GRB050716: Faulkes North Telescope observation
  65. GRB050715: Refined analysis of the Swift-BAT burst
  66. GRB 050715: Swift-BAT detection
  67. GRB 050713b: RTT150 optical observations
  68. GRB050714B: Refined analysis of the Swift-BAT burst
  69. GRB 050714B: optical afterglow
  70. GRB 050714, R-band candidate
  71. GRB 050714, optical observations
  72. GRB 050713A: XRT refined analysis
  73. GRB 050713A: RAPTOR detection of early optical emission
  74. GRB050713B :Swift/UVOT observations
  75. GRB050713b: XRT refined analysis
  76. GRB050712: TNG R-band observations
  77. GRB 050713B: Swift-BAT Refined Analysis
  78. GRB 050713A: Swift/UVOT observation
  79. GRB 050713A : Swift-BAT Refined Analysis
  80. GRB050712: Swift UVOT Observation of Afterglow Emission
  81. GRB 050713A : Lulin R-band observation
  82. GRB 050713A XMM-Newton observation
  83. GRB 050713b : Lulin R-band observations
  84. GRB050713B: Faulkes North Telescope observation
  85. RBO RI observations of GRB 050713A
  86. GRB 050713B
  87. GRB050709 : Chandra source optical counterpart
  88. GRB050713: Liverpool Telescope prompt observations
  89. GRB 050712, optical observations
  90. GRB050709: Candidate X-ray Afterglow from Chandra
  91. GRB050713: possible I-band afterglow
  92. GRB050712: XRT refined analysis
  93. GRB050709: Radio Observations
  94. GRB 050709: Swift UVOT and XRT observations
  95. GRB 050712: Swift-BAT Refined Analysis
  96. GRB050712: UVOT candidate optical counterpart
  97. GRB 050709: LCO40 Observations
  98. GRB050709, optical observations
  99. PROMPT Rc Observations of GRB 050709
  100. GRB 050525a: PROMPT VRcIc Detections

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