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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').
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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"

35957 results found.

  1. GRB050123,optical observation
  2. GRB 050123: KAIT observations
  3. GRB050123: P60 Observations
  4. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  5. CFHTLS optical transient unlikely to be a GRB
  6. Unusual optical transient (GRB ???)
  7. GRB050117a: Radio Observations
  8. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  9. GRB 050117, I-band observations
  10. GRB 050117: Optical observation
  11. GRB050117: Refined XRT position
  12. GRB050117: MASTER optical observations
  13. MASTER:GRB050117 SWIFT
  14. GRB050117: Swift-BAT detection of a long multi-peaked burst
  15. Triangulation of Short Hard GRB050112 (large error box)
  16. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  17. SGR 1806-20 and extragalactic short-duration GRBs
  18. SGR 1806-20: Temporal and Spectral behavior of radio transient
  19. SGR 1806-20, RHESSI observations of the 041227 giant flare
  20. SGR1806: Detection of a Sudden Ionospheric Disturbance
  21. GRB 041217: Optical observations
  22. GRB041219, early time observations
  23. IPN localization of giant flare from SGR1806-20
  24. GRB041219; RXTE ASM Observations
  25. NIR Observations of GRB 041219
  26. GRB041223: decay of the afterglow
  27. GRB 041224: near-infrared observations with REM
  28. GRB 041223: XRT afterglow spectrum and light curve
  29. GRB 041223 Fluence measured by Swift-BAT
  30. GRB041223: optical and NIR observations with REM
  31. GRB 041219: TAROT optical observations
  32. GRB 041218: TAROT optical observations
  33. GRB 041223: J-band observations of the afterglow
  34. GRB 041223: Detection of Optical Transient with LCO40
  35. GRB 041219c: PROMPT Observations
  36. GRB 041218: optical observations
  37. GRB 041219: Second Epoch WSRT Radio Observations
  38. GRB 041219: WSRT Radio Afterglow Detection
  39. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  40. GRB 041218: Optical observations
  41. GRB 041219 : optical follow-up observations
  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. GRB 041219 ,optical observation
  49. GRB 041219: Radio Afterglow Detection
  50. GRB 041218 : Radio Observations
  51. GRB 041218: R-band optical observations
  52. GRB041219: Confirmed NIR Afterglow
  53. GRB041218: Continued P60 Optical Observations
  54. GRB 041218: Optical Observation
  55. GRB 041219: Infrared Afterglow Candidate
  56. GRB041219, BVRcIc field calibration
  57. GRB 041219: Infrared Afterglow Candidate
  58. GRB041218, BVRcIc field calibration
  59. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  60. GRB041219: P60 Optical Observations
  61. GRB 041219 - A long GRB detected by INTEGRAL
  62. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  63. GRB 041217: PROMPT Observations
  64. GRB041218: optical observations
  65. GRB041217: optical limit 30 min after GRB
  66. GRB 041218; optical candidate
  67. GRB 041218: Optical observations
  68. GRB 041217: LCO40 Optical Observations and Possible Candidates
  69. GRB 041218 - A long GRB detected by integral
  70. GRB041217: Optical Observations
  71. GRB041217: P60 Optical Observations
  72. GRB041217: Infrared Observations
  73. GRB041217: The First GRB Located On-Board Swift
  74. GRB041211: Faulkes Telescope continued optical monitoring
  75. Optical Transient in Lynx not a GRB
  76. Optical transient (GRB?) in Lynx
  77. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  78. GRB041211: Continued P60 Observations
  79. GRB041211: RAPTOR observations
  80. GRB041211: Ashra Prototype optical observation
  81. GRB041211, Faulkes Telescope optical observation
  82. GRB041211, BVRcIc field calibration
  83. GRB 041211: Infrared Observations
  84. GRB 041211: KAIT observations
  85. GRB 041211: Optical follow-up in East Asian region
  86. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  87. GRB041211: P60 optical imaging
  88. GRB970815: Discovery of Optical Afterglow
  89. Distribution of IBAS Alerts for NON-GRB sources
  90. Triangulation of short GRB 041116 (large error box)
  91. GRB 040924: Afterglow Color
  92. GRB 041006: GETS Optical Afterglow Observation
  93. Summary of the recent bursts from SGR 1806-20
  94. GRB 041006: Optical Observations
  95. GRB041006, late-time optical photometry
  96. IBAS GRB Alert # 2034
  97. GRB041006: RTT150 Optical Observations
  98. Bright bursts from SGR1806-20
  99. GRB 041016: BOOTES-2 simultaneous observation
  100. GRB041006: RTT150 Optical Observations

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