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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"

37752 results found.

  1. Unusual optical transient (GRB ???)
  2. GRB050117a: Radio Observations
  3. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  4. GRB 050117, I-band observations
  5. GRB 050117: Optical observation
  6. GRB050117: Refined XRT position
  7. GRB050117: MASTER optical observations
  8. MASTER:GRB050117 SWIFT
  9. GRB050117: Swift-BAT detection of a long multi-peaked burst
  10. Triangulation of Short Hard GRB050112 (large error box)
  11. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  12. SGR 1806-20 and extragalactic short-duration GRBs
  13. SGR 1806-20: Temporal and Spectral behavior of radio transient
  14. SGR 1806-20, RHESSI observations of the 041227 giant flare
  15. SGR1806: Detection of a Sudden Ionospheric Disturbance
  16. GRB 041217: Optical observations
  17. GRB041219, early time observations
  18. IPN localization of giant flare from SGR1806-20
  19. GRB041219; RXTE ASM Observations
  20. NIR Observations of GRB 041219
  21. GRB041223: decay of the afterglow
  22. GRB 041224: near-infrared observations with REM
  23. GRB 041223: XRT afterglow spectrum and light curve
  24. GRB 041223 Fluence measured by Swift-BAT
  25. GRB041223: optical and NIR observations with REM
  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. GRB 041219c: PROMPT Observations
  31. GRB 041218: optical observations
  32. GRB 041219: Second Epoch WSRT Radio Observations
  33. GRB 041219: WSRT Radio Afterglow Detection
  34. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  35. GRB 041218: Optical observations
  36. GRB 041219 : optical follow-up observations
  37. Deep RAPTOR observations during GRB 041219
  38. GRB 041218 Optical Observations
  39. GRB 041219 Optical Observations
  40. GRB041219c: Third Burst in One Day from Swift-BAT
  41. GRB041219: Optical Afterglow Detection
  42. GRB041219: Continued NIR Observations
  43. GRB 041219 ,optical observation
  44. GRB 041219: Radio Afterglow Detection
  45. GRB 041218 : Radio Observations
  46. GRB 041218: R-band optical observations
  47. GRB041219: Confirmed NIR Afterglow
  48. GRB041218: Continued P60 Optical Observations
  49. GRB 041218: Optical Observation
  50. GRB 041219: Infrared Afterglow Candidate
  51. GRB041219, BVRcIc field calibration
  52. GRB 041219: Infrared Afterglow Candidate
  53. GRB041218, BVRcIc field calibration
  54. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  55. GRB041219: P60 Optical Observations
  56. GRB 041219 - A long GRB detected by INTEGRAL
  57. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  58. GRB 041217: PROMPT Observations
  59. GRB041218: optical observations
  60. GRB041217: optical limit 30 min after GRB
  61. GRB 041218; optical candidate
  62. GRB 041218: Optical observations
  63. GRB 041217: LCO40 Optical Observations and Possible Candidates
  64. GRB 041218 - A long GRB detected by integral
  65. GRB041217: Optical Observations
  66. GRB041217: P60 Optical Observations
  67. GRB041217: Infrared Observations
  68. GRB041217: The First GRB Located On-Board Swift
  69. GRB041211: Faulkes Telescope continued optical monitoring
  70. Optical Transient in Lynx not a GRB
  71. Optical transient (GRB?) in Lynx
  72. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  73. GRB041211: Continued P60 Observations
  74. GRB041211: RAPTOR observations
  75. GRB041211: Ashra Prototype optical observation
  76. GRB041211, Faulkes Telescope optical observation
  77. GRB041211, BVRcIc field calibration
  78. GRB 041211: Infrared Observations
  79. GRB 041211: KAIT observations
  80. GRB 041211: Optical follow-up in East Asian region
  81. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  82. GRB041211: P60 optical imaging
  83. GRB970815: Discovery of Optical Afterglow
  84. Distribution of IBAS Alerts for NON-GRB sources
  85. Triangulation of short GRB 041116 (large error box)
  86. GRB 040924: Afterglow Color
  87. GRB 041006: GETS Optical Afterglow Observation
  88. Summary of the recent bursts from SGR 1806-20
  89. GRB 041006: Optical Observations
  90. GRB041006, late-time optical photometry
  91. IBAS GRB Alert # 2034
  92. GRB041006: RTT150 Optical Observations
  93. Bright bursts from SGR1806-20
  94. GRB 041016: BOOTES-2 simultaneous observation
  95. GRB041006: RTT150 Optical Observations
  96. GRB 041016: Optical limits
  97. GRB 041016: Optical limits in V, R, I
  98. GRB 041016:Optical limit during first minute
  99. GRB041016: MASTER: Optical observations
  100. GRB 041015: Optical Observations at Rikubetsu

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