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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"

45421 results found.

  1. GRB050123: P60 Observations
  2. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  3. CFHTLS optical transient unlikely to be a GRB
  4. Unusual optical transient (GRB ???)
  5. GRB050117a: Radio Observations
  6. GRB050117a: Refined analysis
  7. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  8. GRB050117: Palomar WIRC Ks-band observations
  9. GRB050117b: Swift-BAT detection of a weak burst
  10. GRB050117: optical observation
  11. GRB 050117, I-band observations
  12. GRB 050117: Optical observation
  13. GRB050117: Refined XRT position
  14. GRB050117: MASTER optical observations
  15. MASTER:GRB050117 SWIFT
  16. GRB050117: Swift-BAT detection of a long multi-peaked burst
  17. GRB050117: Swift XRT Position
  18. SGR 1806-20: RXTE/PCA pulse frequency during flare
  19. Triangulation of Short Hard GRB050112 (large error box)
  20. SGR 1806-20: Further low frequency GMRT results
  21. SGR1806-20: Swift-BAT observations of two additional bursts
  22. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  23. Further VLA observations of SGR 1806-20
  24. SGR 1806-20 and extragalactic short-duration GRBs
  25. Further ATCA observations of SGR 1806-20
  26. Fourth Epoch VLA observations of SGR 1806-20
  27. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  28. SGR 1806-20: Temporal and Spectral behavior of radio transient
  29. ATCA observations of SGR 1806-20
  30. SGR 1806-20, RHESSI observations of the 041227 giant flare
  31. Third epoch observations of SGR 1806-20 with VLA
  32. Second Epoch VLA observations of SGR 1806-20
  33. Second-epoch VLA observations of SGR 1806-20
  34. SGR1806: Detection of a Sudden Ionospheric Disturbance
  35. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  36. VLA observations of SGR 1806-20
  37. SGR1806 VLA Observations
  38. VLA observations of SGR 1806-20
  39. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  40. GRB 041217: Optical observations
  41. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  42. GRB041219, early time observations
  43. Detection of the SGR 1806-20 giant outburst back-scattered by the
  44. The giant outburst from SGR 1806-20
  45. IPN localization of giant flare from SGR1806-20
  46. Giant flare from SGR 1806-20 detected by INTEGRAL
  47. GRB041228: ROTSE-III Optical Observations
  48. GRB041228: Swift-BAT detection of a burst
  49. GRB041219; RXTE ASM Observations
  50. NIR Observations of GRB 041219
  51. GRB041226: ROTSE-III Optical Observations
  52. GRB041226: Swift-BAT detection of a burst
  53. GRB041223: decay of the afterglow
  54. GRB041224: ROTSE-III Optical Observations
  55. GRB 041224: near-infrared observations with REM
  56. GRB 041223: XRT afterglow spectrum and light curve
  57. GRB 041223 Fluence measured by Swift-BAT
  58. GRB041224: Swift-BAT detection of a soft burst
  59. GRB041223: optical and NIR observations with REM
  60. Swift-BAT Time History of GRB041219
  61. GRB 041219: TAROT optical observations
  62. GRB 041218: TAROT optical observations
  63. GRB 041223: J-band observations of the afterglow
  64. GRB 041223: Detection of Optical Transient with LCO40
  65. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  66. GRB 041219c: PROMPT Observations
  67. GRB041223: ROTSE-III Optical Observations
  68. GRB041223: Swift-BAT detection of a bright long burst
  69. GRB 041218: optical observations
  70. Very high activity of SGR 1806-20
  71. GRB 041219: Second Epoch WSRT Radio Observations
  72. GRB 041219: WSRT Radio Afterglow Detection
  73. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  74. GRB 041218: Optical observations
  75. GRB 041219 : optical follow-up observations
  76. GRB041220: Swift-BAT burst
  77. Deep RAPTOR observations during GRB 041219
  78. GRB 041218 Optical Observations
  79. GRB 041219 Optical Observations
  80. GRB041219c: Third Burst in One Day from Swift-BAT
  81. GRB041219: Optical Afterglow Detection
  82. GRB041219: Continued NIR Observations
  83. GRB041219b: A Swift-BAT burst
  84. GRB 041219 ,optical observation
  85. GRB 041219: Radio Afterglow Detection
  86. GRB 041218 : Radio Observations
  87. GRB 041218: R-band optical observations
  88. GRB041218: Liverpool Telescope optical observations
  89. GRB041218: optical observations
  90. GRB041219: Confirmed NIR Afterglow
  91. GRB041218: Continued P60 Optical Observations
  92. Swift-BAT detection of the bright long burst GRB041219
  93. GRB 041218: Optical Observation
  94. GRB 041219: Infrared Afterglow Candidate
  95. GRB041219, BVRcIc field calibration
  96. GRB 041219: Infrared Afterglow Candidate
  97. GRB041218, BVRcIc field calibration
  98. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  99. GRB041219: P60 Optical Observations
  100. GRB 041219 - A long GRB detected by INTEGRAL

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