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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"

26119 results found.

  1. GRB 051105: Swift-BAT refined analysis
  2. GRB 051105: Optical limit
  3. GRB 051105: Swift detection of a short burst
  4. GRB 051016B host spectroscopy and redshift
  5. GRB051016B: optical observation
  6. GRB 051022: RTT150 optical observations
  7. GRB051028: optical observations
  8. GRB051028: Swift/UVOT upper limits
  9. GRB051028: confirmation of the afterglow
  10. GRB051028: WHT optical candidate
  11. GRB051028: Swift XRT Position
  12. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  13. GRB051022: Swift XRT measurement of jet break
  14. GRB051021B: Swift/UVOT Upper limits
  15. GRB 051022: XRT Refined Spectral and Temporal Analysis
  16. GRB051012: Swift-XRT analysis
  17. GRB051021B: Swift XRT refined analysis
  18. GRB051021a: optical observations
  19. GRB 051022: WSRT Radio Detection
  20. GRB051022: host galaxy redshift
  21. GRB 051022: Swift/UVOT Upper Limits
  22. GRB051022: Radio Counterpart
  23. GRB051022: IR observations
  24. GRB 051022: SOAR JKs Observations
  25. GRB051021A: Swift XRT refined analysis
  26. GRB051022: Optical Observations
  27. GRB 051022: Magellan NIR imaging
  28. GRB 051021: PROMPT RcIc Observations
  29. GRB051021b: Magellan IR Imaging
  30. GRB 051021: Correction
  31. GRB 051022, J & K-band observation
  32. GRB 051021, SMARTS optical/IR observations
  33. GRB051022: Swift XRT Position
  34. GRB 051021: P200 Ks Observations
  35. GRB 051021: MDM Upper Limit
  36. GRB051021: Swift/UVOT Upper Limits
  37. GRB 051021B: Refined analysis of the Swift-BAT burst
  38. GRB051021B: Swift XRT Position
  39. GRB 051021: SOAR NIR Observations
  40. GRB 051021B: Swift detection of a burst
  41. GRB051021: Swift XRT analysis
  42. GRB 051021 : optical afterglow observation at Lulin
  43. GRB 051021: Optical observations and candidate afterglow
  44. GRB051021.63
  45. Swift-BAT trigger 160640 is not a real GRB
  46. Swift-BAT trigger 160619 is not a GRB
  47. Swift-BAT triggered on a posible CR Shower or possible GRB
  48. GRB 050502b: Optical limit
  49. GRB 051016b: Optical limit
  50. Afterglow candidate of GRB 051016B observed at Lulin
  51. GRB 051016b: Gemini Near IR Observations
  52. GRB 051016A: Swift/UVOT upper limits
  53. GRB 051016B: refined analysis of the Swift/XRT data
  54. GRB 051016B: Swift/UVOT detection
  55. GRB 051016B : Optical follow-up at Lulin
  56. GRB 051016B: Refined analysis of the Swift-BAT burst
  57. GRB 051016B: Swift detection of a soft burst
  58. GRB 051016: Swift-BAT refined analysis
  59. GRB051016 XMM-Newton observation
  60. GRB051016: Swift XRT refined analysis.
  61. GRB 051016: LCO optical and near-IR imaging
  62. GRB 051016: PROMPT Observations
  63. GRB051016: Swift detection of a burst
  64. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  65. GRB051006: optical observations
  66. GRB 051012: Swift-BAT detection of burst yesterday
  67. Swift trigger 159578 is not a burst
  68. Swift-BAT Trigger 159578 is a possible burst
  69. GRB050805A: Rc optical observations
  70. GRB 051006: Swift/UVOT Upper Limits
  71. GRB051008: optical candidate
  72. GRB 051008 - a low redshift low-luminosity burst?
  73. GRB051008: optical observation
  74. GRB051008: Swift XRT refined analysis
  75. GRB051008 - Swift UVOT upper limits
  76. Konus-Wind observation of GRB 051008
  77. GRB051008: Final refined analysis of the Swift-BAT burst
  78. GRB 051008: R-band upper limit
  79. GRB051008: Refined analysis of the Swift-BAT burst
  80. GRB051008: Radio Observation
  81. GRB 051008: Swift XRT position
  82. GRB 051008, optical observations
  83. GRB 051008: early Swift XRT analysis
  84. GRB 051008: Swift UVOT Candidate
  85. GRB051008: Swift-BAT detection of a bright burst
  86. GRB 051006: P60 Observations
  87. GRB 051006: XRT refined analysis
  88. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  89. GRB 051006: optical observations at Sierra Nevada
  90. GRB051006: Refined analysis of the Swift-BAT burst
  91. GRB 051006: XRT position
  92. GRB051006: Swift detection of a burst
  93. GRB 050906, summary of radio observations
  94. Swift-BAT triggers 158261 and 158262 Retraction
  95. GRB051001: Swift UVOT Upper Limits
  96. GRB 050925: Second Epoch WSRT Radio Observations
  97. GRB 051001: Swift XRT refined analysis
  98. GRB 051001, optical observations at Mt. John
  99. GRB 051001: I-band limit
  100. GRB 051001: AAT infra-red observations

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