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

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