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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"
  1. GRB 050802 : Lulin Optical follow-up observation
  2. GRB 050802: Swift-BAT refined analysis
  3. GRB050801: Optical photometry and decay index
  4. GRB 050802: XRT position
  5. GRB 050802: Swift Gamma-ray Burst
  6. GRB050801: Swift/UVOT Optical and UV detections
  7. GRB 050730: Preliminary Analysis of MIKE Spectrum
  8. GCN 050801: early Swift XRT analysis results
  9. GRB 050801: Swift-BAT refined analysis
  10. GRB 050801, SMARTS optical/IR afterglow observations
  11. GRB 050801, afterglow observations
  12. GRB 050730, corrected photometry and break?
  13. GRB 050801: ROTSE-III Early Afterglow Break
  14. GRB050801: Swift-BAT detection of a burst
  15. GRB050801: GCN XRT position is incorrect
  16. GRB 050801: ROTSE-III Detection of Possible Counterpart
  17. GRB 050730: XRT refined analysis
  18. Correction to GCN Circ 3476 on GRB050525A
  19. GRB 050730: early TAROT optical observations
  20. GRB 050726: PROMPT Rc Observations
  21. GRB 050730: RTT150 optical observations
  22. Swift/UVOT photometry of GRB050730
  23. GRB 050730, spectra and optical photometry
  24. GRB050730: Refined BAT analysis of the Swift-BAT burst
  25. GRB 050730: Swift XRT afterglow observations
  26. GRB 050730 XMM-Newton observation
  27. GRB 050730: PROMPT VRcIc Observations
  28. GRB050730, afterglow observations
  29. GRB050730: confirmation of redshift
  30. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  31. GRB 050730, SMARTS optical/IR afterglow observations
  32. GRB 050730 : Planned XMM-Newton observation
  33. GRB050730: Liverpool Telescope optical observations
  34. GRB 050730, optical candidate
  35. GRB050730: Swift-BAT detection of a weak burst
  36. GRB 050713A: Swift XRT extended light curve
  37. GRB 050709: PROMPT Rc Observations
  38. GRB050713b: Maidanak optical observations
  39. GRB 050724: Secure Host Redshift from Keck
  40. GRB 050724: WHT optical observations
  41. GRB050726: Swift UVOT observations
  42. GRB 050724: Chandra Observations of the X-ray Afterglow
  43. GRB050724: Refined Radio Position
  44. GRB050713: analysis of the XMM-Newton observation
  45. GRB 050724, SMARTS optical/IR afterglow observations
  46. GRB 050726, SMARTS optical/IR observations
  47. Swift-BAT trigger 147918 is not a real GRB
  48. GRB 050727: RTT150 optical observations
  49. GRB050724: VLT observations of the variable source
  50. GRB050727: KAIT optical limit
  51. GRB050709: Second Epoch Chandra Observation
  52. GRB 050726: PROMPT Rc Observations
  53. GRB050709: Second Epoch Chandra Observation
  54. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  55. GRB050724: Further Radio Observations
  56. GRB 050726: early Swift XRT analysis results
  57. GRB050726: Swift-BAT detection of a weak burst
  58. GRB 050724: Optical Variability in Nearby Galaxy
  59. GRB 050724: J-band observations
  60. GRB 050724: GMOS Imaging and Spectroscopy
  61. GRB 050724: SWIFT XRT refined position
  62. RXTE ASM Detection of GRB050724
  63. GRB050724: Radio Observation
  64. GRB 050724: spectroscopy of object in the XRT error circle
  65. GRB 050724: Optical limit
  66. GRB 050724: optical and near-IR observations
  67. GRB 050724: Optical imaging/astrometry
  68. GRB 050724: RTT150 optical observations
  69. GRB 050724: Swift/UVOT Upper Limit
  70. GRB 050724: early Swift XRT analysis results
  71. GRB 050724 : Lulin early R-band monitoring observations
  72. GRB050724: Refined analysis of the Swift-BAT possible short burst
  73. GRB 050724: possible host galaxy in DSS
  74. GRB050724: a short-burst detected by Swift
  75. Swift-BAT trigger 147325 is not due to a real GRB
  76. GRB050723: XRT distributed coordinates are not related to the burst
  77. GRB 050721: early afterglow light curve
  78. GRB 050721A: Swift-BAT refined analysis
  79. Correction to GCN Circ 3474 on GRB050525A
  80. GRB 050721A: Early Swift XRT analysis results
  81. GRB050721A: optical decay
  82. GRB 050721: optical afterglow confirmed
  83. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  84. GRB 050721a: Optical Observations
  85. GRB050721A: Swift-BAT detection of a weak burst
  86. GRB 050709: Refined Spectral and Temporal Properties
  87. GRB 050717: PROMPT RcIc Observations
  88. GRB050714b: Radio Observation
  89. GRB050712: Radio Observations
  90. GRB 050714a: Refined XRT analysis and afterglow confirmation
  91. GRB050713a: Radio Observation
  92. Swift-BAT trigger 146731 is not a real GRB
  93. GRB 050712, Tautenburg optical afterglow observations
  94. Swift-BAT detection of a possible GRB
  95. GRB 050714B: VLT R-band observations
  96. GRB 050717: Additional LCO observations
  97. GRB050717
  98. GRB 050716; J-band observations
  99. Konus-Wind observation of GRB 050717
  100. GRB 050717: LCO near-IR observations

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