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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"

45684 results found.

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

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