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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').
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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"

41780 results found.

  1. GRB 050117: Optical observation
  2. GRB050117: Refined XRT position
  3. GRB050117: MASTER optical observations
  4. MASTER:GRB050117 SWIFT
  5. GRB050117: Swift-BAT detection of a long multi-peaked burst
  6. GRB050117: Swift XRT Position
  7. SGR 1806-20: RXTE/PCA pulse frequency during flare
  8. Triangulation of Short Hard GRB050112 (large error box)
  9. SGR 1806-20: Further VLA Observations
  10. SGR 1806-20: Further low frequency GMRT results
  11. SGR 1806-20: Further VLA Observations
  12. SGR1806-20: Swift-BAT observations of two additional bursts
  13. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  14. Further VLA observations of SGR 1806-20
  15. SGR 1806-20 and extragalactic short-duration GRBs
  16. Further ATCA observations of SGR 1806-20
  17. Fourth Epoch VLA observations of SGR 1806-20
  18. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  19. SGR 1806-20: Temporal and Spectral behavior of radio transient
  20. ATCA observations of SGR 1806-20
  21. SGR 1806-20, RHESSI observations of the 041227 giant flare
  22. Third epoch observations of SGR 1806-20 with VLA
  23. Second Epoch VLA observations of SGR 1806-20
  24. Second-epoch VLA observations of SGR 1806-20
  25. SGR1806: Detection of a Sudden Ionospheric Disturbance
  26. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  27. VLA observations of SGR 1806-20
  28. SGR1806 VLA Observations
  29. VLA observations of SGR 1806-20
  30. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  31. GRB 041217: Optical observations
  32. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  33. GRB041219, early time observations
  34. Detection of the SGR 1806-20 giant outburst back-scattered by the
  35. The giant outburst from SGR 1806-20
  36. IPN localization of giant flare from SGR1806-20
  37. Giant flare from SGR 1806-20 detected by INTEGRAL
  38. GRB041228: ROTSE-III Optical Observations
  39. GRB041228: Swift-BAT detection of a burst
  40. GRB041219; RXTE ASM Observations
  41. NIR Observations of GRB 041219
  42. GRB041226: ROTSE-III Optical Observations
  43. GRB041226: Swift-BAT detection of a burst
  44. GRB041223: decay of the afterglow
  45. GRB041224: ROTSE-III Optical Observations
  46. GRB 041224: near-infrared observations with REM
  47. GRB 041223: XRT afterglow spectrum and light curve
  48. GRB 041223 Fluence measured by Swift-BAT
  49. GRB041224: Swift-BAT detection of a soft burst
  50. GRB041223: optical and NIR observations with REM
  51. Swift-BAT Time History of GRB041219
  52. GRB 041219: TAROT optical observations
  53. GRB 041218: TAROT optical observations
  54. GRB 041223: J-band observations of the afterglow
  55. GRB 041223: Detection of Optical Transient with LCO40
  56. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  57. GRB 041219c: PROMPT Observations
  58. GRB041223: ROTSE-III Optical Observations
  59. GRB041223: Swift-BAT detection of a bright long burst
  60. GRB 041218: optical observations
  61. Very high activity of SGR 1806-20
  62. GRB 041219: Second Epoch WSRT Radio Observations
  63. GRB 041219: WSRT Radio Afterglow Detection
  64. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  65. GRB 041218: Optical observations
  66. GRB 041219 : optical follow-up observations
  67. GRB041220: Swift-BAT burst
  68. Deep RAPTOR observations during GRB 041219
  69. GRB 041218 Optical Observations
  70. GRB 041219 Optical Observations
  71. GRB041219c: Third Burst in One Day from Swift-BAT
  72. GRB041219: Optical Afterglow Detection
  73. GRB041219: Continued NIR Observations
  74. GRB041219b: A Swift-BAT burst
  75. GRB 041219: Radio Afterglow Detection
  76. GRB 041218 : Radio Observations
  77. GRB 041218: R-band optical observations
  78. GRB041218: Liverpool Telescope optical observations
  79. GRB041218: optical observations
  80. GRB041219: Confirmed NIR Afterglow
  81. GRB041218: Continued P60 Optical Observations
  82. Swift-BAT detection of the bright long burst GRB041219
  83. GRB 041218: Optical Observation
  84. GRB 041219: Infrared Afterglow Candidate
  85. GRB041219, BVRcIc field calibration
  86. GRB 041219: Infrared Afterglow Candidate
  87. GRB041218, BVRcIc field calibration
  88. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  89. GRB041219: P60 Optical Observations
  90. GRB 041219 - A long GRB detected by INTEGRAL
  91. GRB 041217: PROMPT Observations
  92. GRB041218: optical observations
  93. GRB041217: optical limit 30 min after GRB
  94. GRB 041218; optical candidate
  95. GRB 041218: Optical observations
  96. GRB 041217: LCO40 Optical Observations and Possible Candidates
  97. GRB 041218 - A long GRB detected by integral
  98. GRB041217: Optical Observations
  99. GRB041217: NIR and optical observations with REM
  100. GRB041217: P60 Optical Observations

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