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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

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

42805 results found.

  1. GRB 050124: K-band afterglow observations
  2. GRB050126: Burst Parameters Measured by BAT
  3. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  4. GRB 050126: Prompt XRT detection and localization
  5. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  6. GRB050124: No Swift UVOT Detection of Afterglow Emission
  7. GRB 050117a: Radio Observations
  8. GRB 050124: NIR Candidates from Keck/NIRC
  9. GRB050124,optical observation
  10. GRB050124: Updated Swift XRT Position and Fluxes
  11. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  12. GRB050124: Refined BAT position, spectral and fluence information
  13. GRB050124: Swift-BAT position of a double-peaked burst
  14. GRB050123,optical observation
  15. GRB 050123: KAIT observations
  16. GRB050123: P60 Observations
  17. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  18. CFHTLS optical transient unlikely to be a GRB
  19. Unusual optical transient (GRB ???)
  20. GRB050117a: Radio Observations
  21. GRB050117a: Refined analysis
  22. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  23. GRB050117: Palomar WIRC Ks-band observations
  24. GRB050117b: Swift-BAT detection of a weak burst
  25. GRB050117: optical observation
  26. GRB 050117, I-band observations
  27. GRB 050117: Optical observation
  28. GRB050117: Refined XRT position
  29. GRB050117: Swift-BAT detection of a long multi-peaked burst
  30. GRB050117: Swift XRT Position
  31. SGR 1806-20: RXTE/PCA pulse frequency during flare
  32. Triangulation of Short Hard GRB050112 (large error box)
  33. SGR 1806-20: Further VLA Observations
  34. SGR 1806-20: Further low frequency GMRT results
  35. SGR 1806-20: Further VLA Observations
  36. SGR1806-20: Swift-BAT observations of two additional bursts
  37. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  38. Further VLA observations of SGR 1806-20
  39. SGR 1806-20 and extragalactic short-duration GRBs
  40. Further ATCA observations of SGR 1806-20
  41. Fourth Epoch VLA observations of SGR 1806-20
  42. SGR 1806-20: Temporal and Spectral behavior of radio transient
  43. ATCA observations of SGR 1806-20
  44. SGR 1806-20, RHESSI observations of the 041227 giant flare
  45. Third epoch observations of SGR 1806-20 with VLA
  46. Second Epoch VLA observations of SGR 1806-20
  47. Second-epoch VLA observations of SGR 1806-20
  48. SGR1806: Detection of a Sudden Ionospheric Disturbance
  49. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  50. VLA observations of SGR 1806-20
  51. SGR1806 VLA Observations
  52. VLA observations of SGR 1806-20
  53. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  54. GRB 041217: Optical observations
  55. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  56. GRB041219, early time observations
  57. Detection of the SGR 1806-20 giant outburst back-scattered by the
  58. The giant outburst from SGR 1806-20
  59. IPN localization of giant flare from SGR1806-20
  60. Giant flare from SGR 1806-20 detected by INTEGRAL
  61. GRB041228: ROTSE-III Optical Observations
  62. GRB041228: Swift-BAT detection of a burst
  63. GRB041219; RXTE ASM Observations
  64. NIR Observations of GRB 041219
  65. GRB041226: ROTSE-III Optical Observations
  66. GRB041226: Swift-BAT detection of a burst
  67. GRB041223: decay of the afterglow
  68. GRB041224: ROTSE-III Optical Observations
  69. GRB 041224: near-infrared observations with REM
  70. GRB 041223: XRT afterglow spectrum and light curve
  71. GRB 041223 Fluence measured by Swift-BAT
  72. GRB041224: Swift-BAT detection of a soft burst
  73. GRB041223: optical and NIR observations with REM
  74. Swift-BAT Time History of GRB041219
  75. GRB 041219: TAROT optical observations
  76. GRB 041218: TAROT optical observations
  77. GRB 041223: J-band observations of the afterglow
  78. GRB 041223: Detection of Optical Transient with LCO40
  79. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  80. GRB 041219c: PROMPT Observations
  81. GRB041223: ROTSE-III Optical Observations
  82. GRB041223: Swift-BAT detection of a bright long burst
  83. GRB 041218: optical observations
  84. GRB 041219: Second Epoch WSRT Radio Observations
  85. GRB 041219: WSRT Radio Afterglow Detection
  86. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  87. GRB 041218: Optical observations
  88. GRB041220: Swift-BAT burst
  89. Deep RAPTOR observations during GRB 041219
  90. GRB 041218 Optical Observations
  91. GRB 041219 Optical Observations
  92. GRB041219c: Third Burst in One Day from Swift-BAT
  93. GRB041219: Optical Afterglow Detection
  94. GRB041219: Continued NIR Observations
  95. GRB041219b: A Swift-BAT burst
  96. GRB 041219 ,optical observation
  97. GRB 041219: Radio Afterglow Detection
  98. GRB 041218 : Radio Observations
  99. GRB 041218: R-band optical observations
  100. GRB041218: Liverpool Telescope optical observations

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