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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"

42961 results found.

  1. GRB050117: MASTER optical observations
  2. MASTER:GRB050117 SWIFT
  3. GRB050117: Swift-BAT detection of a long multi-peaked burst
  4. GRB050117: Swift XRT Position
  5. SGR 1806-20: RXTE/PCA pulse frequency during flare
  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. SGR 1806-20 and extragalactic short-duration GRBs
  13. Further ATCA observations of SGR 1806-20
  14. Fourth Epoch VLA observations of SGR 1806-20
  15. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  16. SGR 1806-20: Temporal and Spectral behavior of radio transient
  17. ATCA observations of SGR 1806-20
  18. SGR 1806-20, RHESSI observations of the 041227 giant flare
  19. Second Epoch VLA observations of SGR 1806-20
  20. Second-epoch VLA observations of SGR 1806-20
  21. SGR1806: Detection of a Sudden Ionospheric Disturbance
  22. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  23. VLA observations of SGR 1806-20
  24. SGR1806 VLA Observations
  25. VLA observations of SGR 1806-20
  26. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  27. GRB 041217: Optical observations
  28. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  29. GRB041219, early time observations
  30. Detection of the SGR 1806-20 giant outburst back-scattered by the
  31. The giant outburst from SGR 1806-20
  32. IPN localization of giant flare from SGR1806-20
  33. Giant flare from SGR 1806-20 detected by INTEGRAL
  34. GRB041228: ROTSE-III Optical Observations
  35. GRB041228: Swift-BAT detection of a burst
  36. GRB041219; RXTE ASM Observations
  37. NIR Observations of GRB 041219
  38. GRB041226: ROTSE-III Optical Observations
  39. GRB041226: Swift-BAT detection of a burst
  40. GRB041223: decay of the afterglow
  41. GRB 041224: near-infrared observations with REM
  42. GRB 041223: XRT afterglow spectrum and light curve
  43. GRB 041223 Fluence measured by Swift-BAT
  44. GRB041224: Swift-BAT detection of a soft burst
  45. GRB041223: optical and NIR observations with REM
  46. Swift-BAT Time History of GRB041219
  47. GRB 041219: TAROT optical observations
  48. GRB 041218: TAROT optical observations
  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 041218: Optical observations
  61. GRB 041219 : optical follow-up observations
  62. GRB041220: Swift-BAT burst
  63. Deep RAPTOR observations during GRB 041219
  64. GRB 041218 Optical Observations
  65. GRB 041219 Optical Observations
  66. GRB041219c: Third Burst in One Day from Swift-BAT
  67. GRB041219: Optical Afterglow Detection
  68. GRB041219: Continued NIR Observations
  69. GRB041219b: A Swift-BAT burst
  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 041218: Optical Observation
  79. GRB 041219: Infrared Afterglow Candidate
  80. GRB041219, BVRcIc field calibration
  81. GRB 041219: Infrared Afterglow Candidate
  82. GRB041218, BVRcIc field calibration
  83. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  84. GRB041219: P60 Optical Observations
  85. GRB 041219 - A long GRB detected by INTEGRAL
  86. GRB 041217: PROMPT Observations
  87. GRB041218: optical observations
  88. GRB041217: optical limit 30 min after GRB
  89. GRB 041218: Optical observations
  90. GRB 041217: LCO40 Optical Observations and Possible Candidates
  91. GRB 041218 - A long GRB detected by integral
  92. GRB041217: Optical Observations
  93. GRB041217: NIR and optical observations with REM
  94. GRB041217: P60 Optical Observations
  95. GRB041217: Infrared Observations
  96. GRB041217: The First GRB Located On-Board Swift
  97. GRB041211: Faulkes Telescope continued optical monitoring
  98. Optical Transient in Lynx not a GRB
  99. Optical transient (GRB?) in Lynx
  100. Optical transient (GRB?) in Lynx, UT Dec 11.4436

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