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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"

37680 results found.

  1. GRB050128: Faulkes Telescope South observations
  2. GRB 050124: Radio Observations
  3. GRB 050128: near-infrared observations with REM
  4. GRB050128,optical observations
  5. GRB 050126: A NIR afterglow candidate in the revised XRT error circle
  6. GRB 050126: Radio Observations
  7. GRB050128 Swift-BAT observations
  8. GRB 050128: Swift XRT prompt afterglow position
  9. GRB 050124: K-band afterglow observations
  10. GRB050126: MASTER optical limit for KECK OT
  11. GRB050126: MASTER optical observations
  12. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  13. GRB 050126: Prompt XRT detection and localization
  14. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  15. GRB 050124, SMARTS optical/IR observations
  16. GRB 050117a: Radio Observations
  17. GRB 050124 I-band observation
  18. GRB 050124: NIR Candidates from Keck/NIRC
  19. GRB050124,optical observation
  20. GRB 050124 : Lulin R-band follow-up observation
  21. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  22. GRB 050123 : I-band follow-up observation
  23. GRB050123: optical limit 1.8h before GRB
  24. GRB050123,optical observation
  25. GRB 050123: KAIT observations
  26. GRB050123: P60 Observations
  27. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  28. CFHTLS optical transient unlikely to be a GRB
  29. Unusual optical transient (GRB ???)
  30. GRB050117a: Radio Observations
  31. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  32. GRB 050117, I-band observations
  33. GRB 050117: Optical observation
  34. GRB050117: Refined XRT position
  35. GRB050117: MASTER optical observations
  36. MASTER:GRB050117 SWIFT
  37. GRB050117: Swift-BAT detection of a long multi-peaked burst
  38. Triangulation of Short Hard GRB050112 (large error box)
  39. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  40. SGR 1806-20 and extragalactic short-duration GRBs
  41. SGR 1806-20: Temporal and Spectral behavior of radio transient
  42. SGR 1806-20, RHESSI observations of the 041227 giant flare
  43. SGR1806: Detection of a Sudden Ionospheric Disturbance
  44. GRB 041217: Optical observations
  45. GRB041219, early time observations
  46. IPN localization of giant flare from SGR1806-20
  47. GRB041219; RXTE ASM Observations
  48. NIR Observations of GRB 041219
  49. GRB041223: decay of the afterglow
  50. GRB 041224: near-infrared observations with REM
  51. GRB 041223: XRT afterglow spectrum and light curve
  52. GRB 041223 Fluence measured by Swift-BAT
  53. GRB041223: optical and NIR observations with REM
  54. GRB 041219: TAROT optical observations
  55. GRB 041218: TAROT optical observations
  56. GRB 041223: J-band observations of the afterglow
  57. GRB 041223: Detection of Optical Transient with LCO40
  58. GRB 041219c: PROMPT Observations
  59. GRB 041218: optical observations
  60. GRB 041219: Second Epoch WSRT Radio Observations
  61. GRB 041219: WSRT Radio Afterglow Detection
  62. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  63. GRB 041218: Optical observations
  64. GRB 041219 : optical follow-up observations
  65. Deep RAPTOR observations during GRB 041219
  66. GRB 041218 Optical Observations
  67. GRB 041219 Optical Observations
  68. GRB041219c: Third Burst in One Day from Swift-BAT
  69. GRB041219: Optical Afterglow Detection
  70. GRB041219: Continued NIR Observations
  71. GRB 041219 ,optical observation
  72. GRB 041219: Radio Afterglow Detection
  73. GRB 041218 : Radio Observations
  74. GRB 041218: R-band optical observations
  75. GRB041219: Confirmed NIR Afterglow
  76. GRB041218: Continued P60 Optical Observations
  77. GRB 041218: Optical Observation
  78. GRB 041219: Infrared Afterglow Candidate
  79. GRB041219, BVRcIc field calibration
  80. GRB 041219: Infrared Afterglow Candidate
  81. GRB041218, BVRcIc field calibration
  82. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  83. GRB041219: P60 Optical Observations
  84. GRB 041219 - A long GRB detected by INTEGRAL
  85. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  86. GRB 041217: PROMPT Observations
  87. GRB041218: optical observations
  88. GRB041217: optical limit 30 min after GRB
  89. GRB 041218; optical candidate
  90. GRB 041218: Optical observations
  91. GRB 041217: LCO40 Optical Observations and Possible Candidates
  92. GRB 041218 - A long GRB detected by integral
  93. GRB041217: Optical Observations
  94. GRB041217: P60 Optical Observations
  95. GRB041217: Infrared Observations
  96. GRB041217: The First GRB Located On-Board Swift
  97. GRB041211: Faulkes Telescope continued optical monitoring
  98. Optical Transient in Lynx not a GRB
  99. Optical transient (GRB?) in Lynx
  100. Optical transient (GRB?) in Lynx, UT Dec 11.4436

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