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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"

42180 results found.

  1. GRB 051111A: ROTSE-III Detection of Possible Counterpart
  2. GRB 051008 Tautenburg Supernova Search
  3. GRB 051109B. Radio Observations
  4. GRB 051109A
  5. GRB051109A - radio observations
  6. GRB 051105a: GETS optical limit
  7. GRB 051109A: KAIT optical observations
  8. Early RAPTOR measurements of GRB 051109a - the movie.
  9. Konus-Wind observation of GRB 051109A
  10. GRB 051109B: ROTSE-III Optical Limits
  11. GRB 051109A: Swift-UVOT Observations
  12. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  13. GRB051109B: no UVOT source detected
  14. GRB051109B: XRT refined analysis
  15. GRB 051109B : Lulin Optical Observations
  16. GRB 051109A : Lulin BVRI Optical afterglow observation
  17. GRB051109A: further steepening in the X-ray light curve
  18. GRB051109A: XRT refined analysis
  19. GRB 051109a: BOOTES R & I-band detection of the early afterglow
  20. GRB051109B: XRT position
  21. GRB 051109B: Super-LOTIS Observations
  22. GRB 051109B Kiso optical follow-up observation
  23. GRB051105B: REM Optical observation
  24. GRB 051109B: Swift detection of a burst
  25. GRB 051109: HET Optical Spectrum and Absorption Redshift
  26. GRB 051109: PROMPT Detections
  27. GRB 051109: Rc and Ic observations
  28. GRB 051109: Swift-BAT refined analysis
  29. GRB 051109a: IR Photometry and Astrometry
  30. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  31. GRB051109: Swift detection of a burst
  32. GRB 051109: ROTSE-III Detection of Possible Counterpart
  33. GRB051105B: Swift/XRT upper limit
  34. GRB051105B: Swift/UVOT upper limit
  35. GRB051103: optical observations
  36. GRB 051103, optical observations
  37. GRB051103: MASTER: OT limit and host galaxy candidates
  38. GRB051028: Swift-XRT refined analysis
  39. GRB 051105a, observation from Naini Tal and OSN
  40. GRB 051105A, 2nd epoch optical observations
  41. GRB 051105a: MDM Observations
  42. GRB 051105A: TNG optical observations
  43. GRB051105A: Swift/UVOT Observations
  44. GRB 051105A, radio observations
  45. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  46. GRB 051105A, optical observations
  47. XRT observations of GRB 051105A
  48. GRB 051105b: ART optical limits
  49. GRB051105B - A long GRB detected by INTEGRAL
  50. GRB 051105B (INTEGRAL 2701): Optical observation
  51. GRB 051105: Swift-BAT refined analysis
  52. GRB 051105: Optical limit
  53. GRB 051105: Swift detection of a short burst
  54. GRB 051016B host spectroscopy and redshift
  55. GRB051016B: optical observation
  56. Recent GRB UBVRcIc field photometry
  57. Konus-Wind observation of GRB 051028
  58. GRB 051022: RTT150 optical observations
  59. GRB 051021A: RTT150 optical observations
  60. GRB051028 SARA Observation
  61. GRB051028: optical observations
  62. GRB051028: Swift/UVOT upper limits
  63. GRB051028: confirmation of the afterglow
  64. GRB051028: WHT optical candidate
  65. GRB051028: Swift XRT Position
  66. GRB051028:MASTER observations
  67. GRB 051028 (=H3951): A GRB localized by HETE
  68. GRB051028:MASTER optical observations
  69. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  70. SGR 1806-20: continued moderate activity seen with INTEGRAL
  71. GRB 051021, Optical Observations
  72. GRB 051022: XRT Refined Spectral and Temporal Analysis
  73. GRB 051022, refined optical astrometry
  74. Chandra Observations of GRB 051022
  75. GRB051012: Swift-XRT analysis
  76. GRB 051022 Chandra Observations scheduled
  77. GRB051021B: Swift XRT refined analysis
  78. GRB051021a: optical observations
  79. GRB 051022: WSRT Radio Detection
  80. GRB 051022, mm counterpart
  81. GRB051022: host galaxy redshift
  82. GRB 051022: Swift/UVOT Upper Limits
  83. GRB051022: Radio Counterpart
  84. GRB051022: IR observations
  85. GRB 051022: SOAR JKs Observations
  86. GRB051021A: Swift XRT refined analysis
  87. Konus-Wind observation of GRB 051022
  88. GRB051022: Optical Observations
  89. GRB 051022: Magellan NIR imaging
  90. GRB051021b: Magellan IR Imaging
  91. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  92. GRB 051022, J & K-band observation
  93. GRB 051021, SMARTS optical/IR observations
  94. GRB051022: Swift XRT Position
  95. GRB 051021: P200 Ks Observations
  96. IPN triangulation of GRB051022 (=H3950)
  97. GRB 051021: MDM Upper Limit
  98. GRB 051022 (=H3950): SXC Flight Localization is Valid
  99. GRB051021: Swift/UVOT Upper Limits
  100. GRB 051021B: Refined analysis of the Swift-BAT burst

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