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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.

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

18695 results found.

  1. GRB 050128: Radio observations
  2. Further analysis of the short Swift-BAT GRB 050202
  3. GRB 050202: Second epoch radio observations
  4. GRB050202: Radio Observations
  5. GRB 050202: Short burst detected by Swift-BAT
  6. SGR1806-20: Swift-BAT detection of a large normal burst
  7. GRB050128: Faulkes Telescope South observations
  8. GRB050128,optical observations
  9. GRB050126: Updated Swift XRT Position
  10. SGR 1806-20: GMRT results at 240 MHz band.
  11. SGR 1806-20: low frequency GMRT results of 2005 Jan 16.
  12. GRB 050126: Radio Observations
  13. GRB050128 Swift-BAT observations
  14. GRB 050128: Swift XRT prompt afterglow position
  15. GRB 050124: K-band afterglow observations
  16. GRB050126: MASTER optical limit for KECK OT
  17. GRB050126: Burst Parameters Measured by BAT
  18. GRB050126: MASTER optical observations
  19. GRB 050126: Prompt XRT detection and localization
  20. GRB050124: No Swift UVOT Detection of Afterglow Emission
  21. GRB 050117a: Radio Observations
  22. GRB050124,optical observation
  23. GRB050124: Updated Swift XRT Position and Fluxes
  24. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  25. GRB050124: Refined BAT position, spectral and fluence information
  26. GRB050124: Swift-BAT position of a double-peaked burst
  27. GRB050117a: Radio Observations
  28. GRB050117a: Refined analysis
  29. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  30. GRB050117b: Swift-BAT detection of a weak burst
  31. GRB050117: optical observation
  32. GRB 050117, I-band observations
  33. GRB 050117: Optical observation
  34. GRB050117: Refined XRT position
  35. GRB050117: MASTER optical observations
  36. MASTER:GRB050117 SWIFT
  37. GRB050117: Swift-BAT detection of a long multi-peaked burst
  38. GRB050117: Swift XRT Position
  39. SGR 1806-20: RXTE/PCA pulse frequency during flare
  40. SGR 1806-20: Further VLA Observations
  41. SGR 1806-20: Further low frequency GMRT results
  42. SGR 1806-20: Further VLA Observations
  43. SGR1806-20: Swift-BAT observations of two additional bursts
  44. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  45. Further VLA observations of SGR 1806-20
  46. SGR 1806-20 and extragalactic short-duration GRBs
  47. Further ATCA observations of SGR 1806-20
  48. Fourth Epoch VLA observations of SGR 1806-20
  49. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  50. SGR 1806-20: Temporal and Spectral behavior of radio transient
  51. ATCA observations of SGR 1806-20
  52. SGR 1806-20, RHESSI observations of the 041227 giant flare
  53. Third epoch observations of SGR 1806-20 with VLA
  54. Second Epoch VLA observations of SGR 1806-20
  55. Second-epoch VLA observations of SGR 1806-20
  56. SGR1806: Detection of a Sudden Ionospheric Disturbance
  57. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  58. VLA observations of SGR 1806-20
  59. SGR1806 VLA Observations
  60. VLA observations of SGR 1806-20
  61. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  62. GRB 041217: Optical observations
  63. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  64. Detection of the SGR 1806-20 giant outburst back-scattered by the
  65. The giant outburst from SGR 1806-20
  66. Giant flare from SGR 1806-20 detected by INTEGRAL
  67. GRB041228: ROTSE-III Optical Observations
  68. GRB041228: Swift-BAT detection of a burst
  69. GRB041219; RXTE ASM Observations
  70. NIR Observations of GRB 041219
  71. GRB041226: ROTSE-III Optical Observations
  72. GRB041226: Swift-BAT detection of a burst
  73. GRB041223: decay of the afterglow
  74. GRB041224: ROTSE-III Optical Observations
  75. GRB 041223: XRT afterglow spectrum and light curve
  76. GRB 041223 Fluence measured by Swift-BAT
  77. GRB041224: Swift-BAT detection of a soft burst
  78. GRB041223: optical and NIR observations with REM
  79. Swift-BAT Time History of GRB041219
  80. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  81. GRB041223: ROTSE-III Optical Observations
  82. GRB041223: Swift-BAT detection of a bright long burst
  83. Very high activity of SGR 1806-20
  84. GRB041220: Swift-BAT burst
  85. GRB 041219 Optical Observations
  86. GRB041219c: Third Burst in One Day from Swift-BAT
  87. GRB041219b: A Swift-BAT burst
  88. Swift-BAT detection of the bright long burst GRB041219
  89. GRB041217: optical limit 30 min after GRB
  90. GRB041217: Optical Observations
  91. GRB041217: NIR and optical observations with REM
  92. GRB041217: P60 Optical Observations
  93. GRB041217: Infrared Observations
  94. GRB041217: The First GRB Located On-Board Swift
  95. Summary of the recent bursts from SGR 1806-20
  96. IBAS GRB Alert # 2034
  97. Bright bursts from SGR1806-20
  98. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  99. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  100. Very strong outburst from SGR 1806-20 detected with INTEGRAL

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