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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"

45635 results found.

  1. GRB 051105a: GETS optical limit
  2. GRB 051109b: GETS observation
  3. GRB 051109A: KAIT optical observations
  4. Early RAPTOR measurements of GRB 051109a - the movie.
  5. Konus-Wind observation of GRB 051109A
  6. GRB 051109B: Swift-BAT refined analysis
  7. GRB 051109B: ROTSE-III Optical Limits
  8. GRB 051109A: Swift-UVOT Observations
  9. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  10. GRB051109B: no UVOT source detected
  11. GRB051109B: XRT refined analysis
  12. GRB 051109B : Lulin Optical Observations
  13. GRB 051109A : Lulin BVRI Optical afterglow observation
  14. GRB051109A: further steepening in the X-ray light curve
  15. GRB051109A: XRT refined analysis
  16. GRB 051109a: BOOTES R & I-band detection of the early afterglow
  17. GRB051109B: XRT position
  18. GRB 051109B: Super-LOTIS Observations
  19. GRB 051109B Kiso optical follow-up observation
  20. GRB051105B: REM Optical observation
  21. GRB 051109B: Swift detection of a burst
  22. GRB 051109: HET Optical Spectrum and Absorption Redshift
  23. GRB 051109: PROMPT Detections
  24. GRB 051109: Rc and Ic observations
  25. GRB051109: Early Super-LOTIS Detection
  26. GRB 051109: Swift-BAT refined analysis
  27. GRB 051109a: IR Photometry and Astrometry
  28. GRB 051109a: MDM Observations
  29. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  30. GRB051109: Swift detection of a burst
  31. GRB 051109a: IR Detections
  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. GRB051103:_MASTER_optical_observations
  46. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  47. GRB 051105A, optical observations
  48. XRT observations of GRB 051105A
  49. GRB 051105: Swift-BAT improved refined analysis
  50. GRB 051105b: ART optical limits
  51. GRB051105B - A long GRB detected by INTEGRAL
  52. GRB 051105B (INTEGRAL 2701): Optical observation
  53. GRB 051105: Swift-BAT refined analysis
  54. GRB 051105: Optical limit
  55. GRB 051105: Swift detection of a short burst
  56. IBAS Alert 2700: Not a GRB
  57. GRB 051016B host spectroscopy and redshift
  58. GRB051016B: optical observation
  59. Recent GRB UBVRcIc field photometry
  60. Konus-Wind observation of GRB 051028
  61. GRB051028:MASTER correction and final results
  62. GRB 051022: RTT150 optical observations
  63. GRB 051021A: RTT150 optical observations
  64. GRB051028 SARA Observation
  65. GRB051028: optical observations
  66. GRB051028: Swift/UVOT upper limits
  67. GRB051028: confirmation of the afterglow
  68. GRB051028: WHT optical candidate
  69. GRB051028: Swift XRT Position
  70. GRB051028:MASTER observations
  71. GRB 051028 (=H3951): A GRB localized by HETE
  72. GRB051028:MASTER optical observations
  73. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  74. GRB051022: Swift XRT measurement of jet break
  75. SGR 1806-20: continued moderate activity seen with INTEGRAL
  76. GRB051021B: Swift/UVOT Upper limits
  77. GRB 051021, Optical Observations
  78. GRB 051022: XRT Refined Spectral and Temporal Analysis
  79. GRB 051022, refined optical astrometry
  80. Chandra Observations of GRB 051022
  81. GRB051012: Swift-XRT analysis
  82. GRB 051022 Chandra Observations scheduled
  83. GRB051021B: Swift XRT refined analysis
  84. GRB051021a: optical observations
  85. GRB 051022: WSRT Radio Detection
  86. GRB 051022, mm counterpart
  87. GRB051022: host galaxy redshift
  88. GRB 051022: Swift/UVOT Upper Limits
  89. GRB051022: Radio Counterpart
  90. GRB051022: IR observations
  91. GRB 051022: SOAR JKs Observations
  92. GRB051021A: Swift XRT refined analysis
  93. Konus-Wind observation of GRB 051022
  94. GRB051022: Optical Observations
  95. GRB 051022: Magellan NIR imaging
  96. GRB 051021: PROMPT RcIc Observations
  97. GRB051021b: Magellan IR Imaging
  98. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  99. GRB 051021: Correction
  100. GRB 051022, J & K-band observation

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