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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. GRB050805a : Null detection report
  2. GRB050730, optical observations
  3. GRB050803, optical observations
  4. Swift-BAT trigger 149118 is very likely not a GRB
  5. Retraction of Swift Trigger 149131 (GRB 050805B)
  6. GRB 050805b: OHP optical limits
  7. GRB 050805b: TAROT optical limits
  8. GRB050805b: MASTER optical observations
  9. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  10. GRB050805a: MASTER optical candidat
  11. Swift-BAT trigger 149118 is probably not a GRB
  12. GRB050802: TNG optical observations
  13. GRB050803: Radio Observation
  14. GRB 050803: RTT150 optical observations
  15. GRB050801: Radio Observation
  16. GRB050730: Radio Detection
  17. GRB050803: CrAO optical observations, possible OT candidate
  18. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  19. GRB 050803: Keck Observations
  20. GRB 050803: Swift-BAT refined analysis
  21. GRB 050802.422: Fading of the afterglow and detection of the host
  22. GRB050803: MASTER further analys
  23. GRB 050803, optical observations
  24. GRB 050803: Magellan Observations
  25. GRB 050803: early Swift XRT analysis results
  26. GRB 050803: TAROT optical limits
  27. GRB050803: MASTER optical observations
  28. GRB050802: Tentative absorption redshift
  29. GRB050803: Swift-BAT detection of a very long burst
  30. GCN GRB observation 050713A
  31. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  32. GRB 050802: Swift/UVOT optical and UV detections
  33. GRB050802: CrAO optical observations
  34. GRB050801: Unchanged decay slope
  35. GRB050802 radio non-detection
  36. GRB 050730: OHP optical observations
  37. GRB 050802: early Swift XRT analysis results
  38. GRB 050802: Swift/UVOT observations
  39. GRB 050802 : Lulin Optical follow-up observation
  40. GRB 050802: Swift-BAT refined analysis
  41. GRB050801: Optical photometry and decay index
  42. GRB 050802: XRT position
  43. GRB 050802: Swift Gamma-ray Burst
  44. GRB050801: Swift/UVOT Optical and UV detections
  45. GRB 050730: Preliminary Analysis of MIKE Spectrum
  46. GCN 050801: early Swift XRT analysis results
  47. GRB 050801: Swift-BAT refined analysis
  48. GRB 050801, SMARTS optical/IR afterglow observations
  49. GRB 050801, afterglow observations
  50. GRB 050730, corrected photometry and break?
  51. GRB 050801: ROTSE-III Early Afterglow Break
  52. GRB050801: Swift-BAT detection of a burst
  53. GRB050801: GCN XRT position is incorrect
  54. GRB 050801: ROTSE-III Detection of Possible Counterpart
  55. GRB 050730: XRT refined analysis
  56. Correction to GCN Circ 3476 on GRB050525A
  57. GRB 050730: early TAROT optical observations
  58. GRB 050726: PROMPT Rc Observations
  59. GRB 050730: RTT150 optical observations
  60. Swift/UVOT photometry of GRB050730
  61. GRB 050730, spectra and optical photometry
  62. GRB050730: Refined BAT analysis of the Swift-BAT burst
  63. GRB 050730: Swift XRT afterglow observations
  64. GRB 050730 XMM-Newton observation
  65. GRB 050730: PROMPT VRcIc Observations
  66. GRB050730, afterglow observations
  67. GRB050730: confirmation of redshift
  68. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  69. GRB 050730, SMARTS optical/IR afterglow observations
  70. GRB 050730 : Planned XMM-Newton observation
  71. GRB050730: Liverpool Telescope optical observations
  72. GRB 050730, optical candidate
  73. GRB050730: Swift-BAT detection of a weak burst
  74. GRB 050713A: Swift XRT extended light curve
  75. GRB 050709: PROMPT Rc Observations
  76. GRB050713b: Maidanak optical observations
  77. GRB 050724: Secure Host Redshift from Keck
  78. GRB 050724: WHT optical observations
  79. GRB050726: Swift UVOT observations
  80. GRB 050724: Chandra Observations of the X-ray Afterglow
  81. GRB050724: Refined Radio Position
  82. GRB050713: analysis of the XMM-Newton observation
  83. GRB 050724, SMARTS optical/IR afterglow observations
  84. GRB 050726, SMARTS optical/IR observations
  85. Swift-BAT trigger 147918 is not a real GRB
  86. GRB 050727: RTT150 optical observations
  87. GRB050724: VLT observations of the variable source
  88. GRB050727: KAIT optical limit
  89. GRB050709: Second Epoch Chandra Observation
  90. GRB 050726: PROMPT Rc Observations
  91. GRB050709: Second Epoch Chandra Observation
  92. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  93. GRB050724: Further Radio Observations
  94. GRB 050726: early Swift XRT analysis results
  95. GRB050726: Swift-BAT detection of a weak burst
  96. GRB 050724: Optical Variability in Nearby Galaxy
  97. GRB 050724: J-band observations
  98. GRB 050724: GMOS Imaging and Spectroscopy
  99. GRB 050724: SWIFT XRT refined position
  100. RXTE ASM Detection of GRB050724

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