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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"

42896 results found.

  1. GRB 051109a: MDM Observations
  2. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  3. GRB051109: Swift detection of a burst
  4. GRB 051109a: IR Detections
  5. GRB 051109: ROTSE-III Detection of Possible Counterpart
  6. GRB051105B: Swift/XRT upper limit
  7. GRB051105B: Swift/UVOT upper limit
  8. GRB051103: optical observations
  9. GRB 051103, optical observations
  10. GRB051103: MASTER: OT limit and host galaxy candidates
  11. GRB051028: Swift-XRT refined analysis
  12. GRB 051105A, 2nd epoch optical observations
  13. GRB 051105a: MDM Observations
  14. GRB 051105A: TNG optical observations
  15. GRB051105A: Swift/UVOT Observations
  16. GRB 051105A, radio observations
  17. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  18. GRB 051105A, optical observations
  19. XRT observations of GRB 051105A
  20. GRB 051105: Swift-BAT improved refined analysis
  21. GRB 051105b: ART optical limits
  22. GRB051105B - A long GRB detected by INTEGRAL
  23. GRB 051105B (INTEGRAL 2701): Optical observation
  24. GRB 051105: Swift-BAT refined analysis
  25. GRB 051105: Swift detection of a short burst
  26. IBAS Alert 2700: Not a GRB
  27. GRB 051016B host spectroscopy and redshift
  28. GRB051016B: optical observation
  29. Recent GRB UBVRcIc field photometry
  30. Konus-Wind observation of GRB 051028
  31. GRB 051021A: RTT150 optical observations
  32. GRB051028 SARA Observation
  33. GRB051028: optical observations
  34. GRB051028: Swift/UVOT upper limits
  35. GRB051028: confirmation of the afterglow
  36. GRB051028: WHT optical candidate
  37. GRB 051028 (=H3951): A GRB localized by HETE
  38. GRB051022: Swift XRT measurement of jet break
  39. SGR 1806-20: continued moderate activity seen with INTEGRAL
  40. GRB051021B: Swift/UVOT Upper limits
  41. GRB 051021, Optical Observations
  42. GRB 051022: XRT Refined Spectral and Temporal Analysis
  43. GRB 051022, refined optical astrometry
  44. Chandra Observations of GRB 051022
  45. GRB051012: Swift-XRT analysis
  46. GRB 051022 Chandra Observations scheduled
  47. GRB051021B: Swift XRT refined analysis
  48. GRB051021a: optical observations
  49. GRB 051022: WSRT Radio Detection
  50. GRB 051022, mm counterpart
  51. GRB051022: host galaxy redshift
  52. GRB 051022: Swift/UVOT Upper Limits
  53. GRB051022: Radio Counterpart
  54. GRB051022: IR observations
  55. GRB 051022: SOAR JKs Observations
  56. GRB051021A: Swift XRT refined analysis
  57. Konus-Wind observation of GRB 051022
  58. GRB051022: Optical Observations
  59. GRB 051022: Magellan NIR imaging
  60. GRB 051021: PROMPT RcIc Observations
  61. GRB051021b: Magellan IR Imaging
  62. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  63. GRB 051021: Correction
  64. GRB 051022, J & K-band observation
  65. GRB 051021, SMARTS optical/IR observations
  66. GRB051022: Swift XRT Position
  67. GRB 051021: P200 Ks Observations
  68. IPN triangulation of GRB051022 (=H3950)
  69. GRB 051021: MDM Upper Limit
  70. GRB 051022 (=H3950): SXC Flight Localization is Valid
  71. GRB 051021B: Refined analysis of the Swift-BAT burst
  72. GRB 051022: SSO40 Optical Observations
  73. GRB051022 (=H3590), A GRB Detected By HETE
  74. GRB 051022: Optical observations
  75. GRB051021B: Swift XRT Position
  76. GRB 051021: SOAR NIR Observations
  77. GRB 051021B: Swift detection of a burst
  78. GRB051021 (=H3947): Refined Analysis
  79. GRB 051021: Optical observations
  80. GRB 051021: ROTSE-III Confirmation of Optical Counterpart
  81. GRB 051021: Optical observations and candidate afterglow
  82. Swift-BAT trigger 160640 is not a real GRB
  83. GRB051021: A GRB Localized by HETE
  84. Swift-BAT trigger 160619 is not a GRB
  85. Swift-BAT triggered on a posible CR Shower or possible GRB
  86. GRB 050502b: Optical limit
  87. GRB 051016b: Gemini Near IR Observations
  88. GRB 051016A: Swift/UVOT upper limits
  89. GRB 051016B: refined analysis of the Swift/XRT data
  90. GRB 051016B: Swift/UVOT detection
  91. GRB 051016B,optical observation
  92. GRB 051016B : Optical follow-up at Lulin
  93. GRB 051016B: Refined analysis of the Swift-BAT burst
  94. GRB 051016B: Swift detection of a soft burst
  95. GRB 051016: Swift-BAT refined analysis
  96. GRB051016 XMM-Newton observation
  97. GRB051016: Swift XRT refined analysis.
  98. GRB 051016: LCO optical and near-IR imaging
  99. GRB 051016: PROMPT Observations
  100. GRB051016: Swift detection of a burst

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