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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

27168 results found.

  1. GRB051114: results of the Swift-XRT observation
  2. GRB 051109B : Nainital upper limits
  3. GRB 051114: Radio Observations
  4. GRB 051114: Swift-BAT refined analysis
  5. GRB050925: analysis of the XMM-Newton observation
  6. GRB 051114: Swift-BAT detection of a short burst
  7. GRB 051111: Further spectroscopic analysis
  8. GRB 051111: Radio afterglow
  9. GRB 051113: Swift-BAT refined analysis
  10. GRB051103: Radio Observations
  11. GRB/SGR 050925: XMM-Newton ToO observation
  12. GRB051111: Swift/UVOT Observations
  13. GRB051111: XRT preliminary analysis
  14. GRB 051111: Swift-BAT refined analysis
  15. GRB 051109A Optical Observations
  16. GRB 051111A : Lulin BVRI multi band afterglow observation
  17. GRB051111a: SARA Observations
  18. GRB 051111a: IR photometry
  19. GRB 051109B. Radio Observations
  20. GRB 051109A
  21. GRB051109A - radio observations
  22. GRB 051109B: Swift-BAT refined analysis
  23. GRB 051109A: Swift-UVOT Observations
  24. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  25. GRB051109B: no UVOT source detected
  26. GRB051109B: XRT refined analysis
  27. GRB 051109B : Lulin Optical Observations
  28. GRB 051109A : Lulin BVRI Optical afterglow observation
  29. GRB051109A: further steepening in the X-ray light curve
  30. GRB051109A: XRT refined analysis
  31. GRB 051109B: Super-LOTIS Observations
  32. GRB051105B: REM Optical observation
  33. GRB 051109B: Swift detection of a burst
  34. GRB 051109: Rc and Ic observations
  35. GRB 051109: Swift-BAT refined analysis
  36. GRB 051109a: IR Photometry and Astrometry
  37. GRB051109: Swift detection of a burst
  38. GRB 051109a: IR Detections
  39. GRB051105B: Swift/XRT upper limit
  40. GRB051105B: Swift/UVOT upper limit
  41. GRB051103: MASTER: OT limit and host galaxy candidates
  42. GRB051028: Swift-XRT refined analysis
  43. GRB 051105a, observation from Naini Tal and OSN
  44. GRB 051105a: MDM Observations
  45. GRB 051105A: TNG optical observations
  46. GRB051105A: Swift/UVOT Observations
  47. GRB 051105A, radio observations
  48. GRB051103:_MASTER_optical_observations
  49. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  50. GRB 051105A, optical observations
  51. XRT observations of GRB 051105A
  52. GRB 051105b: ART optical limits
  53. GRB 051105B (INTEGRAL 2701): Optical observation
  54. GRB 051105: Swift detection of a short burst
  55. Recent GRB UBVRcIc field photometry
  56. GRB051028 SARA Observation
  57. GRB051028: optical observations
  58. GRB051028: Swift/UVOT upper limits
  59. GRB051028: Swift XRT Position
  60. GRB051028:MASTER observations
  61. GRB051021B: Swift/UVOT Upper limits
  62. GRB 051021, Optical Observations
  63. GRB 051022: XRT Refined Spectral and Temporal Analysis
  64. GRB051012: Swift-XRT analysis
  65. GRB051021B: Swift XRT refined analysis
  66. GRB 051022, mm counterpart
  67. GRB 051022: Swift/UVOT Upper Limits
  68. GRB051022: Radio Counterpart
  69. GRB051022: IR observations
  70. GRB051021A: Swift XRT refined analysis
  71. GRB051022: Optical Observations
  72. GRB051021b: Magellan IR Imaging
  73. GRB 051021, SMARTS optical/IR observations
  74. GRB051022: Swift XRT Position
  75. GRB 051021: P200 Ks Observations
  76. GRB 051022 (=H3950): SXC Flight Localization is Valid
  77. GRB051021: Swift/UVOT Upper Limits
  78. GRB 051021B: Refined analysis of the Swift-BAT burst
  79. GRB 051022: SSO40 Optical Observations
  80. GRB051022,optical observation
  81. GRB 051021,optical observation
  82. GRB 051021B: Swift detection of a burst
  83. GRB 051021 : optical afterglow observation at Lulin
  84. GRB 051021: Optical observations and candidate afterglow
  85. GRB051021.63
  86. GRB051021.6: MASTER optical observation
  87. GRB051021: A GRB Localized by HETE
  88. Swift-BAT triggered on a posible CR Shower or possible GRB
  89. GRB 051016b: Optical limit
  90. Afterglow candidate of GRB 051016B observed at Lulin
  91. GRB 051016A: Swift/UVOT upper limits
  92. GRB 051016B: refined analysis of the Swift/XRT data
  93. GRB 051016B: Swift/UVOT detection
  94. GRB 051016B,optical observation
  95. GRB 051016B : Optical follow-up at Lulin
  96. GRB 051016B: Refined analysis of the Swift-BAT burst
  97. GRB 051016B: Swift detection of a soft burst
  98. GRB 051016: Swift-BAT refined analysis
  99. GRB051016 XMM-Newton observation
  100. GRB051016: Swift XRT refined analysis.

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