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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"

45681 results found.

  1. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  2. GRB 041217: Optical observations
  3. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  4. GRB041219, early time observations
  5. Detection of the SGR 1806-20 giant outburst back-scattered by the
  6. The giant outburst from SGR 1806-20
  7. IPN localization of giant flare from SGR1806-20
  8. Giant flare from SGR 1806-20 detected by INTEGRAL
  9. GRB041228: ROTSE-III Optical Observations
  10. GRB041228: Swift-BAT detection of a burst
  11. GRB041219; RXTE ASM Observations
  12. NIR Observations of GRB 041219
  13. GRB041226: ROTSE-III Optical Observations
  14. GRB041226: Swift-BAT detection of a burst
  15. GRB041223: decay of the afterglow
  16. GRB041224: ROTSE-III Optical Observations
  17. GRB 041224: near-infrared observations with REM
  18. GRB 041223: XRT afterglow spectrum and light curve
  19. GRB 041223 Fluence measured by Swift-BAT
  20. GRB041224: Swift-BAT detection of a soft burst
  21. GRB041223: optical and NIR observations with REM
  22. Swift-BAT Time History of GRB041219
  23. GRB 041219: TAROT optical observations
  24. GRB 041218: TAROT optical observations
  25. GRB 041223: J-band observations of the afterglow
  26. GRB 041223: Detection of Optical Transient with LCO40
  27. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  28. GRB 041219c: PROMPT Observations
  29. GRB041223: ROTSE-III Optical Observations
  30. GRB041223: Swift-BAT detection of a bright long burst
  31. GRB 041218: optical observations
  32. Very high activity of SGR 1806-20
  33. GRB 041219: Second Epoch WSRT Radio Observations
  34. GRB 041219: WSRT Radio Afterglow Detection
  35. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  36. GRB 041218: Optical observations
  37. GRB 041219 : optical follow-up observations
  38. GRB041220: Swift-BAT burst
  39. Deep RAPTOR observations during GRB 041219
  40. GRB 041218 Optical Observations
  41. GRB 041219 Optical Observations
  42. GRB041219c: Third Burst in One Day from Swift-BAT
  43. GRB041219: Optical Afterglow Detection
  44. GRB041219: Continued NIR Observations
  45. GRB041219b: A Swift-BAT burst
  46. GRB 041219 ,optical observation
  47. GRB 041219: Radio Afterglow Detection
  48. GRB 041218 : Radio Observations
  49. GRB 041218: R-band optical observations
  50. GRB041218: Liverpool Telescope optical observations
  51. GRB041218: optical observations
  52. GRB041219: Confirmed NIR Afterglow
  53. GRB041218: Continued P60 Optical Observations
  54. Swift-BAT detection of the bright long burst GRB041219
  55. GRB 041218: Optical Observation
  56. GRB 041219: Infrared Afterglow Candidate
  57. GRB041219, BVRcIc field calibration
  58. GRB 041219: Infrared Afterglow Candidate
  59. GRB041218, BVRcIc field calibration
  60. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  61. GRB041219: P60 Optical Observations
  62. GRB 041219 - A long GRB detected by INTEGRAL
  63. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  64. GRB 041217: PROMPT Observations
  65. GRB041218: optical observations
  66. GRB041217: optical limit 30 min after GRB
  67. GRB 041218; optical candidate
  68. GRB 041218: Optical observations
  69. GRB 041217: LCO40 Optical Observations and Possible Candidates
  70. GRB 041218 - A long GRB detected by integral
  71. GRB041217: Optical Observations
  72. GRB041217: NIR and optical observations with REM
  73. GRB041217: P60 Optical Observations
  74. GRB041217: Infrared Observations
  75. GRB041217: The First GRB Located On-Board Swift
  76. GRB041211: Faulkes Telescope continued optical monitoring
  77. Optical Transient in Lynx not a GRB
  78. Optical transient (GRB?) in Lynx
  79. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  80. GRB041211: Continued P60 Observations
  81. GRB041211: RAPTOR observations
  82. GRB041211: Ashra Prototype optical observation
  83. GRB041211, Faulkes Telescope optical observation
  84. GRB041211, BVRcIc field calibration
  85. GRB041211,optical observation
  86. GRB 041211: Infrared Observations
  87. GRB 041211: KAIT observations
  88. GRB 041211: Optical follow-up in East Asian region
  89. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  90. GRB041211: P60 optical imaging
  91. GRB970815: Discovery of Optical Afterglow
  92. Distribution of IBAS Alerts for NON-GRB sources
  93. Triangulation of short GRB 041116 (large error box)
  94. GRB041015: Near-Infrared observations
  95. GRB 040924: Afterglow Color
  96. GRB 041006: GETS Optical Afterglow Observation
  97. Summary of the recent bursts from SGR 1806-20
  98. GRB 041006: Optical Observations
  99. GRB041006, late-time optical photometry
  100. GRB041015, optical observation in CrAO

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