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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 051105a, observation from Naini Tal and OSN
  2. GRB 051105A, 2nd epoch optical observations
  3. GRB 051105a: MDM Observations
  4. GRB 051105A: TNG optical observations
  5. GRB051105A: Swift/UVOT Observations
  6. GRB 051105A, radio observations
  7. GRB051103:_MASTER_optical_observations
  8. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  9. GRB 051105A, optical observations
  10. XRT observations of GRB 051105A
  11. GRB 051105: Swift-BAT improved refined analysis
  12. GRB 051105b: ART optical limits
  13. GRB051105B - A long GRB detected by INTEGRAL
  14. GRB 051105B (INTEGRAL 2701): Optical observation
  15. GRB 051105: Swift-BAT refined analysis
  16. GRB 051105: Optical limit
  17. GRB 051105: Swift detection of a short burst
  18. IBAS Alert 2700: Not a GRB
  19. GRB 051016B host spectroscopy and redshift
  20. GRB051016B: optical observation
  21. Recent GRB UBVRcIc field photometry
  22. Konus-Wind observation of GRB 051028
  23. GRB051028:MASTER correction and final results
  24. GRB 051022: RTT150 optical observations
  25. GRB 051021A: RTT150 optical observations
  26. GRB051028 SARA Observation
  27. GRB051028: optical observations
  28. GRB051028: Swift/UVOT upper limits
  29. GRB051028: confirmation of the afterglow
  30. GRB051028: WHT optical candidate
  31. GRB051028: Swift XRT Position
  32. GRB051028:MASTER observations
  33. GRB 051028 (=H3951): A GRB localized by HETE
  34. GRB051028:MASTER optical observations
  35. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  36. GRB051022: Swift XRT measurement of jet break
  37. SGR 1806-20: continued moderate activity seen with INTEGRAL
  38. GRB051021B: Swift/UVOT Upper limits
  39. GRB 051021, Optical Observations
  40. GRB 051022: XRT Refined Spectral and Temporal Analysis
  41. GRB 051022, refined optical astrometry
  42. Chandra Observations of GRB 051022
  43. GRB051012: Swift-XRT analysis
  44. GRB 051022 Chandra Observations scheduled
  45. GRB051021B: Swift XRT refined analysis
  46. GRB051021a: optical observations
  47. GRB 051022: WSRT Radio Detection
  48. GRB 051022, mm counterpart
  49. GRB051022: host galaxy redshift
  50. GRB 051022: Swift/UVOT Upper Limits
  51. GRB051022: Radio Counterpart
  52. GRB051022: IR observations
  53. GRB 051022: SOAR JKs Observations
  54. GRB051021A: Swift XRT refined analysis
  55. Konus-Wind observation of GRB 051022
  56. GRB051022: Optical Observations
  57. GRB 051022: Magellan NIR imaging
  58. GRB 051021: PROMPT RcIc Observations
  59. GRB051021b: Magellan IR Imaging
  60. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  61. GRB 051021: Correction
  62. GRB 051022, J & K-band observation
  63. GRB 051021, SMARTS optical/IR observations
  64. GRB051022: Swift XRT Position
  65. GRB 051021: P200 Ks Observations
  66. IPN triangulation of GRB051022 (=H3950)
  67. GRB 051021: MDM Upper Limit
  68. GRB 051022 (=H3950): SXC Flight Localization is Valid
  69. GRB051021: Swift/UVOT Upper Limits
  70. GRB 051021B: Refined analysis of the Swift-BAT burst
  71. GRB 051022: SSO40 Optical Observations
  72. GRB051022,optical observation
  73. GRB 051022A: ROTSE-III Optical Limits
  74. GRB051022 (=H3590), A GRB Detected By HETE
  75. GRB 051022: Optical observations
  76. GRB 051021,optical observation
  77. GRB051021B: Swift XRT Position
  78. GRB 051021: SOAR NIR Observations
  79. GRB 051021B: Swift detection of a burst
  80. GRB051021: Swift XRT analysis
  81. GRB051021 (=H3947): Refined Analysis
  82. GRB 051021 : optical afterglow observation at Lulin
  83. GRB 051021: Optical observations
  84. GRB 051021: ROTSE-III Confirmation of Optical Counterpart
  85. GRB 051021: Optical observations and candidate afterglow
  86. GRB051021.63
  87. GRB051021.6: MASTER optical observation
  88. Swift-BAT trigger 160640 is not a real GRB
  89. GRB051021: A GRB Localized by HETE
  90. Swift-BAT trigger 160619 is not a GRB
  91. Swift-BAT triggered on a posible CR Shower or possible GRB
  92. GRB 050502b: Optical limit
  93. GRB 051016b: Optical limit
  94. Afterglow candidate of GRB 051016B observed at Lulin
  95. GRB 051016b: Gemini Near IR Observations
  96. GRB 051016A: Swift/UVOT upper limits
  97. GRB 051016B: refined analysis of the Swift/XRT data
  98. GRB 051016B: Swift/UVOT detection
  99. GRB 051016B,optical observation
  100. GRB 051016B : Optical follow-up at Lulin

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