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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"

45676 results found.

  1. The giant outburst from SGR 1806-20
  2. IPN localization of giant flare from SGR1806-20
  3. Giant flare from SGR 1806-20 detected by INTEGRAL
  4. GRB041228: ROTSE-III Optical Observations
  5. GRB041228: Swift-BAT detection of a burst
  6. GRB041219; RXTE ASM Observations
  7. NIR Observations of GRB 041219
  8. GRB041226: ROTSE-III Optical Observations
  9. GRB041226: Swift-BAT detection of a burst
  10. GRB041223: decay of the afterglow
  11. GRB041224: ROTSE-III Optical Observations
  12. GRB 041224: near-infrared observations with REM
  13. GRB 041223: XRT afterglow spectrum and light curve
  14. GRB 041223 Fluence measured by Swift-BAT
  15. GRB041224: Swift-BAT detection of a soft burst
  16. GRB041223: optical and NIR observations with REM
  17. Swift-BAT Time History of GRB041219
  18. GRB 041219: TAROT optical observations
  19. GRB 041218: TAROT optical observations
  20. GRB 041223: J-band observations of the afterglow
  21. GRB 041223: Detection of Optical Transient with LCO40
  22. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  23. GRB 041219c: PROMPT Observations
  24. GRB041223: ROTSE-III Optical Observations
  25. GRB041223: Swift-BAT detection of a bright long burst
  26. GRB 041218: optical observations
  27. Very high activity of SGR 1806-20
  28. GRB 041219: Second Epoch WSRT Radio Observations
  29. GRB 041219: WSRT Radio Afterglow Detection
  30. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  31. GRB 041218: Optical observations
  32. GRB 041219 : optical follow-up observations
  33. GRB041220: Swift-BAT burst
  34. Deep RAPTOR observations during GRB 041219
  35. GRB 041218 Optical Observations
  36. GRB 041219 Optical Observations
  37. GRB041219c: Third Burst in One Day from Swift-BAT
  38. GRB041219: Optical Afterglow Detection
  39. GRB041219: Continued NIR Observations
  40. GRB041219b: A Swift-BAT burst
  41. GRB 041219 ,optical observation
  42. GRB 041219: Radio Afterglow Detection
  43. GRB 041218 : Radio Observations
  44. GRB 041218: R-band optical observations
  45. GRB041218: Liverpool Telescope optical observations
  46. GRB041218: optical observations
  47. GRB041219: Confirmed NIR Afterglow
  48. GRB041218: Continued P60 Optical Observations
  49. Swift-BAT detection of the bright long burst GRB041219
  50. GRB 041218: Optical Observation
  51. GRB 041219: Infrared Afterglow Candidate
  52. GRB041219, BVRcIc field calibration
  53. GRB 041219: Infrared Afterglow Candidate
  54. GRB041218, BVRcIc field calibration
  55. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  56. GRB041219: P60 Optical Observations
  57. GRB 041219 - A long GRB detected by INTEGRAL
  58. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  59. GRB 041217: PROMPT Observations
  60. GRB041218: optical observations
  61. GRB041217: optical limit 30 min after GRB
  62. GRB 041218; optical candidate
  63. GRB 041218: Optical observations
  64. GRB 041217: LCO40 Optical Observations and Possible Candidates
  65. GRB 041218 - A long GRB detected by integral
  66. GRB041217: Optical Observations
  67. GRB041217: NIR and optical observations with REM
  68. GRB041217: P60 Optical Observations
  69. GRB041217: Infrared Observations
  70. GRB041217: The First GRB Located On-Board Swift
  71. GRB041211: Faulkes Telescope continued optical monitoring
  72. Optical Transient in Lynx not a GRB
  73. Optical transient (GRB?) in Lynx
  74. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  75. GRB041211: Continued P60 Observations
  76. GRB041211: RAPTOR observations
  77. GRB041211: Ashra Prototype optical observation
  78. GRB041211, Faulkes Telescope optical observation
  79. GRB041211, BVRcIc field calibration
  80. GRB041211,optical observation
  81. GRB 041211: Infrared Observations
  82. GRB 041211: KAIT observations
  83. GRB 041211: Optical follow-up in East Asian region
  84. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  85. GRB041211: P60 optical imaging
  86. GRB970815: Discovery of Optical Afterglow
  87. Distribution of IBAS Alerts for NON-GRB sources
  88. Triangulation of short GRB 041116 (large error box)
  89. GRB041015: Near-Infrared observations
  90. GRB 040924: Afterglow Color
  91. GRB 041006: GETS Optical Afterglow Observation
  92. Summary of the recent bursts from SGR 1806-20
  93. GRB 041006: Optical Observations
  94. GRB041006, late-time optical photometry
  95. GRB041015, optical observation in CrAO
  96. IBAS GRB Alert # 2034
  97. GRB041006: RTT150 Optical Observations
  98. GRB041015 : Multi epoch optical observations
  99. HST Observations: XRF 040701 and 040812
  100. Bright bursts from SGR1806-20

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