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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"

24972 results found.

  1. GRB 051117A: Refined analysis of the Swift-BAT burst
  2. GRB 051117B: Refined analysis of the Swift-BAT burst
  3. GRB 051117B,optical observation
  4. GRB 051117B: Lulin R and I band observation
  5. GRB051114: results of the Swift-XRT observation
  6. GRB 051109B : Nainital upper limits
  7. GRB 051114: Radio Observations
  8. GRB 051114: Swift-BAT refined analysis
  9. GRB050925: analysis of the XMM-Newton observation
  10. GRB 051114: Swift-BAT detection of a short burst
  11. GRB 051111: Further spectroscopic analysis
  12. GRB 051111: Radio afterglow
  13. GRB 051113: Swift-BAT refined analysis
  14. GRB051103: Radio Observations
  15. GRB/SGR 050925: XMM-Newton ToO observation
  16. GRB051111: Swift/UVOT Observations
  17. GRB051111: XRT preliminary analysis
  18. GRB 051111: Swift-BAT refined analysis
  19. GRB 051109A Optical Observations
  20. GRB 051111A : Lulin BVRI multi band afterglow observation
  21. GRB051111a: SARA Observations
  22. GRB 051111a: IR photometry
  23. GRB 051109B. Radio Observations
  24. GRB 051109A
  25. GRB051109A - radio observations
  26. GRB 051109B: Swift-BAT refined analysis
  27. GRB 051109A: Swift-UVOT Observations
  28. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  29. GRB051109B: no UVOT source detected
  30. GRB051109B: XRT refined analysis
  31. GRB 051109B : Lulin Optical Observations
  32. GRB 051109A : Lulin BVRI Optical afterglow observation
  33. GRB051109A: further steepening in the X-ray light curve
  34. GRB051109A: XRT refined analysis
  35. GRB 051109B: Super-LOTIS Observations
  36. GRB051105B: REM Optical observation
  37. GRB 051109B: Swift detection of a burst
  38. GRB 051109: Rc and Ic observations
  39. GRB 051109: Swift-BAT refined analysis
  40. GRB 051109a: IR Photometry and Astrometry
  41. GRB051109: Swift detection of a burst
  42. GRB 051109a: IR Detections
  43. GRB051105B: Swift/XRT upper limit
  44. GRB051105B: Swift/UVOT upper limit
  45. GRB051103: MASTER: OT limit and host galaxy candidates
  46. GRB051028: Swift-XRT refined analysis
  47. GRB 051105a, observation from Naini Tal and OSN
  48. GRB 051105a: MDM Observations
  49. GRB 051105A: TNG optical observations
  50. GRB051105A: Swift/UVOT Observations
  51. GRB 051105A, radio observations
  52. GRB051103:_MASTER_optical_observations
  53. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  54. GRB 051105A, optical observations
  55. XRT observations of GRB 051105A
  56. GRB 051105b: ART optical limits
  57. GRB 051105B (INTEGRAL 2701): Optical observation
  58. GRB 051105: Swift detection of a short burst
  59. Recent GRB UBVRcIc field photometry
  60. GRB051028 SARA Observation
  61. GRB051028: optical observations
  62. GRB051028: Swift/UVOT upper limits
  63. GRB051028: Swift XRT Position
  64. GRB051028:MASTER observations
  65. GRB051021B: Swift/UVOT Upper limits
  66. GRB 051021, Optical Observations
  67. GRB 051022: XRT Refined Spectral and Temporal Analysis
  68. GRB051012: Swift-XRT analysis
  69. GRB051021B: Swift XRT refined analysis
  70. GRB 051022, mm counterpart
  71. GRB 051022: Swift/UVOT Upper Limits
  72. GRB051022: Radio Counterpart
  73. GRB051022: IR observations
  74. GRB051021A: Swift XRT refined analysis
  75. GRB051022: Optical Observations
  76. GRB051021b: Magellan IR Imaging
  77. GRB 051021, SMARTS optical/IR observations
  78. GRB051022: Swift XRT Position
  79. GRB 051021: P200 Ks Observations
  80. GRB 051022 (=H3950): SXC Flight Localization is Valid
  81. GRB051021: Swift/UVOT Upper Limits
  82. GRB 051021B: Refined analysis of the Swift-BAT burst
  83. GRB 051022: SSO40 Optical Observations
  84. GRB051022,optical observation
  85. GRB 051021,optical observation
  86. GRB 051021B: Swift detection of a burst
  87. GRB 051021 : optical afterglow observation at Lulin
  88. GRB 051021: Optical observations and candidate afterglow
  89. GRB051021.63
  90. GRB051021.6: MASTER optical observation
  91. GRB051021: A GRB Localized by HETE
  92. Swift-BAT triggered on a posible CR Shower or possible GRB
  93. GRB 051016b: Optical limit
  94. Afterglow candidate of GRB 051016B observed at Lulin
  95. GRB 051016A: Swift/UVOT upper limits
  96. GRB 051016B: refined analysis of the Swift/XRT data
  97. GRB 051016B: Swift/UVOT detection
  98. GRB 051016B,optical observation
  99. GRB 051016B : Optical follow-up at Lulin
  100. GRB 051016B: Refined analysis of the Swift-BAT burst

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