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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"

38581 results found.

  1. GRB050117: Refined XRT position
  2. GRB050117: MASTER optical observations
  3. MASTER:GRB050117 SWIFT
  4. GRB050117: Swift-BAT detection of a long multi-peaked burst
  5. GRB050117: Swift XRT Position
  6. Triangulation of Short Hard GRB050112 (large error box)
  7. SGR 1806-20: Further VLA Observations
  8. SGR 1806-20: Further low frequency GMRT results
  9. SGR 1806-20: Further VLA Observations
  10. SGR1806-20: Swift-BAT observations of two additional bursts
  11. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  12. Further VLA observations of SGR 1806-20
  13. SGR 1806-20 and extragalactic short-duration GRBs
  14. Further ATCA observations of SGR 1806-20
  15. Fourth Epoch VLA observations of SGR 1806-20
  16. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  17. ATCA observations of SGR 1806-20
  18. SGR 1806-20, RHESSI observations of the 041227 giant flare
  19. Third epoch observations of SGR 1806-20 with VLA
  20. Second Epoch VLA observations of SGR 1806-20
  21. Second-epoch VLA observations of SGR 1806-20
  22. SGR1806: Detection of a Sudden Ionospheric Disturbance
  23. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  24. VLA observations of SGR 1806-20
  25. SGR1806 VLA Observations
  26. VLA observations of SGR 1806-20
  27. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  28. GRB 041217: Optical observations
  29. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  30. GRB041219, early time observations
  31. Detection of the SGR 1806-20 giant outburst back-scattered by the
  32. The giant outburst from SGR 1806-20
  33. IPN localization of giant flare from SGR1806-20
  34. Giant flare from SGR 1806-20 detected by INTEGRAL
  35. GRB041228: ROTSE-III Optical Observations
  36. GRB041228: Swift-BAT detection of a burst
  37. GRB041219; RXTE ASM Observations
  38. NIR Observations of GRB 041219
  39. GRB041226: ROTSE-III Optical Observations
  40. GRB041226: Swift-BAT detection of a burst
  41. GRB041223: decay of the afterglow
  42. GRB041224: ROTSE-III Optical Observations
  43. GRB 041224: near-infrared observations with REM
  44. GRB 041223: XRT afterglow spectrum and light curve
  45. GRB 041223 Fluence measured by Swift-BAT
  46. GRB041224: Swift-BAT detection of a soft burst
  47. GRB041223: optical and NIR observations with REM
  48. Swift-BAT Time History of GRB041219
  49. GRB 041223: J-band observations of the afterglow
  50. GRB 041223: Detection of Optical Transient with LCO40
  51. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  52. GRB 041219c: PROMPT Observations
  53. GRB041223: ROTSE-III Optical Observations
  54. GRB041223: Swift-BAT detection of a bright long burst
  55. GRB 041218: optical observations
  56. Very high activity of SGR 1806-20
  57. GRB 041219: Second Epoch WSRT Radio Observations
  58. GRB 041219: WSRT Radio Afterglow Detection
  59. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  60. GRB 041219 : optical follow-up observations
  61. GRB041220: Swift-BAT burst
  62. Deep RAPTOR observations during GRB 041219
  63. GRB 041218 Optical Observations
  64. GRB 041219 Optical Observations
  65. GRB041219c: Third Burst in One Day from Swift-BAT
  66. GRB041219: Optical Afterglow Detection
  67. GRB041219: Continued NIR Observations
  68. GRB041219b: A Swift-BAT burst
  69. GRB 041219 ,optical observation
  70. GRB 041219: Radio Afterglow Detection
  71. GRB 041218 : Radio Observations
  72. GRB 041218: R-band optical observations
  73. GRB041218: Liverpool Telescope optical observations
  74. GRB041218: optical observations
  75. GRB041219: Confirmed NIR Afterglow
  76. GRB041218: Continued P60 Optical Observations
  77. Swift-BAT detection of the bright long burst GRB041219
  78. GRB 041219: Infrared Afterglow Candidate
  79. GRB041219, BVRcIc field calibration
  80. GRB 041219: Infrared Afterglow Candidate
  81. GRB041218, BVRcIc field calibration
  82. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  83. GRB041219: P60 Optical Observations
  84. GRB 041219 - A long GRB detected by INTEGRAL
  85. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  86. GRB 041217: PROMPT Observations
  87. GRB041217: optical limit 30 min after GRB
  88. GRB 041218: Optical observations
  89. GRB 041217: LCO40 Optical Observations and Possible Candidates
  90. GRB 041218 - A long GRB detected by integral
  91. GRB041217: Optical Observations
  92. GRB041217: NIR and optical observations with REM
  93. GRB041217: P60 Optical Observations
  94. GRB041217: Infrared Observations
  95. GRB041217: The First GRB Located On-Board Swift
  96. GRB041211: Faulkes Telescope continued optical monitoring
  97. Optical Transient in Lynx not a GRB
  98. Optical transient (GRB?) in Lynx
  99. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  100. GRB041211: Continued P60 Observations

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