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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

26051 results found.

  1. GRB 051109B : Lulin Optical Observations
  2. GRB 051109A : Lulin BVRI Optical afterglow observation
  3. GRB051109A: further steepening in the X-ray light curve
  4. GRB051109A: XRT refined analysis
  5. GRB 051109a: BOOTES R & I-band detection of the early afterglow
  6. GRB051109B: XRT position
  7. GRB 051109B: Super-LOTIS Observations
  8. GRB 051109B Kiso optical follow-up observation
  9. GRB 051109B: Swift detection of a burst
  10. GRB 051109: HET Optical Spectrum and Absorption Redshift
  11. GRB 051109: PROMPT Detections
  12. GRB 051109: Rc and Ic observations
  13. GRB051109: Early Super-LOTIS Detection
  14. GRB 051109: Swift-BAT refined analysis
  15. GRB 051109a: MDM Observations
  16. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  17. GRB051109: Swift detection of a burst
  18. GRB 051109a: IR Detections
  19. GRB 051109: ROTSE-III Detection of Possible Counterpart
  20. GRB051105B: Swift/XRT upper limit
  21. GRB051105B: Swift/UVOT upper limit
  22. GRB051028: Swift-XRT refined analysis
  23. GRB 051105A, 2nd epoch optical observations
  24. GRB 051105a: MDM Observations
  25. GRB 051105A: TNG optical observations
  26. GRB051105A: Swift/UVOT Observations
  27. GRB 051105A, radio observations
  28. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  29. GRB 051105A, optical observations
  30. XRT observations of GRB 051105A
  31. GRB 051105: Swift-BAT improved refined analysis
  32. GRB 051105b: ART optical limits
  33. GRB 051105: Swift-BAT refined analysis
  34. GRB 051105: Optical limit
  35. GRB 051105: Swift detection of a short burst
  36. GRB 051016B host spectroscopy and redshift
  37. GRB051016B: optical observation
  38. GRB 051022: RTT150 optical observations
  39. GRB051028: optical observations
  40. GRB051028: Swift/UVOT upper limits
  41. GRB051028: confirmation of the afterglow
  42. GRB051028: WHT optical candidate
  43. GRB051028: Swift XRT Position
  44. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  45. GRB051022: Swift XRT measurement of jet break
  46. GRB051021B: Swift/UVOT Upper limits
  47. GRB 051022: XRT Refined Spectral and Temporal Analysis
  48. GRB051012: Swift-XRT analysis
  49. GRB051021B: Swift XRT refined analysis
  50. GRB051021a: optical observations
  51. GRB 051022: WSRT Radio Detection
  52. GRB051022: host galaxy redshift
  53. GRB 051022: Swift/UVOT Upper Limits
  54. GRB051022: Radio Counterpart
  55. GRB051022: IR observations
  56. GRB 051022: SOAR JKs Observations
  57. GRB051021A: Swift XRT refined analysis
  58. GRB051022: Optical Observations
  59. GRB 051022: Magellan NIR imaging
  60. GRB 051021: PROMPT RcIc Observations
  61. GRB051021b: Magellan IR Imaging
  62. GRB 051021: Correction
  63. GRB 051022, J & K-band observation
  64. GRB 051021, SMARTS optical/IR observations
  65. GRB051022: Swift XRT Position
  66. GRB 051021: P200 Ks Observations
  67. GRB 051021: MDM Upper Limit
  68. GRB051021: Swift/UVOT Upper Limits
  69. GRB 051021B: Refined analysis of the Swift-BAT burst
  70. GRB051021B: Swift XRT Position
  71. GRB 051021: SOAR NIR Observations
  72. GRB 051021B: Swift detection of a burst
  73. GRB051021: Swift XRT analysis
  74. GRB 051021 : optical afterglow observation at Lulin
  75. GRB 051021: Optical observations and candidate afterglow
  76. GRB051021.63
  77. Swift-BAT trigger 160640 is not a real GRB
  78. Swift-BAT trigger 160619 is not a GRB
  79. Swift-BAT triggered on a posible CR Shower or possible GRB
  80. GRB 050502b: Optical limit
  81. GRB 051016b: Optical limit
  82. Afterglow candidate of GRB 051016B observed at Lulin
  83. GRB 051016b: Gemini Near IR Observations
  84. GRB 051016A: Swift/UVOT upper limits
  85. GRB 051016B: refined analysis of the Swift/XRT data
  86. GRB 051016B: Swift/UVOT detection
  87. GRB 051016B : Optical follow-up at Lulin
  88. GRB 051016B: Refined analysis of the Swift-BAT burst
  89. GRB 051016B: Swift detection of a soft burst
  90. GRB 051016: Swift-BAT refined analysis
  91. GRB051016 XMM-Newton observation
  92. GRB051016: Swift XRT refined analysis.
  93. GRB 051016: LCO optical and near-IR imaging
  94. GRB 051016: PROMPT Observations
  95. GRB051016: Swift detection of a burst
  96. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  97. GRB051006: optical observations
  98. GRB 051012: Swift-BAT detection of burst yesterday
  99. Swift trigger 159578 is not a burst
  100. Swift-BAT Trigger 159578 is a possible burst

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