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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').
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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"

37707 results found.

  1. GRB050215b: P60 Optical Observations
  2. GRB 050215b: Swift XRT Source Variability
  3. GRB 050215B: candidate afterglow
  4. GRB 050215b : Lulin follow-up observation
  5. GRB 050215b, BOOTES-2 simultaneous optical observations
  6. GRB 050215B: UKIRT K-band imaging
  7. GRB 050215b: Swift XRT Observations
  8. GRB 050215b, BOOTES-1B optical limit
  9. GRB050215A: ROTSE-III Optical Observations
  10. GRB050209: TAROT optical observations
  11. GRB 050209(=U11568): Duration and spectrum
  12. short/hard GRB 050202, optical observations
  13. GRB050209: REM optical observations
  14. GRB 050209 I-band observation
  15. GRB 050209 Optical observations
  16. GRB050209: P60 Optical Observations
  17. GRB050209 (=U11568): A Long GRB Detected by HETE
  18. GRB 050209: Optical observation
  19. GRB 050128: Radio observations
  20. Further analysis of the short Swift-BAT GRB 050202
  21. GRB 050202: Second epoch radio observations
  22. GRB 050129: Optical observations
  23. GRB050202: Radio Observations
  24. GRB 050202: Optical observations with LCO40
  25. GRB 050202: Short burst detected by Swift-BAT
  26. GRB 050128 Optical observation with REM
  27. GRB 050129: a weak long GRB detected with INTEGRAL
  28. GRB050128: Faulkes Telescope South observations
  29. GRB 050124: Radio Observations
  30. GRB 050128: near-infrared observations with REM
  31. GRB050128,optical observations
  32. GRB 050126: A NIR afterglow candidate in the revised XRT error circle
  33. GRB 050126: Radio Observations
  34. GRB050128 Swift-BAT observations
  35. GRB 050128: Swift XRT prompt afterglow position
  36. GRB 050124: K-band afterglow observations
  37. GRB050126: MASTER optical limit for KECK OT
  38. GRB050126: MASTER optical observations
  39. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  40. GRB 050126: Prompt XRT detection and localization
  41. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  42. GRB 050124, SMARTS optical/IR observations
  43. GRB 050117a: Radio Observations
  44. GRB 050124 I-band observation
  45. GRB 050124: NIR Candidates from Keck/NIRC
  46. GRB050124,optical observation
  47. GRB 050124 : Lulin R-band follow-up observation
  48. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  49. GRB 050123 : I-band follow-up observation
  50. GRB050123: optical limit 1.8h before GRB
  51. GRB050123,optical observation
  52. GRB 050123: KAIT observations
  53. GRB050123: P60 Observations
  54. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  55. CFHTLS optical transient unlikely to be a GRB
  56. Unusual optical transient (GRB ???)
  57. GRB050117a: Radio Observations
  58. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  59. GRB 050117, I-band observations
  60. GRB 050117: Optical observation
  61. GRB050117: Refined XRT position
  62. GRB050117: MASTER optical observations
  63. MASTER:GRB050117 SWIFT
  64. GRB050117: Swift-BAT detection of a long multi-peaked burst
  65. Triangulation of Short Hard GRB050112 (large error box)
  66. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  67. SGR 1806-20 and extragalactic short-duration GRBs
  68. SGR 1806-20: Temporal and Spectral behavior of radio transient
  69. SGR 1806-20, RHESSI observations of the 041227 giant flare
  70. SGR1806: Detection of a Sudden Ionospheric Disturbance
  71. GRB 041217: Optical observations
  72. GRB041219, early time observations
  73. IPN localization of giant flare from SGR1806-20
  74. GRB041219; RXTE ASM Observations
  75. NIR Observations of GRB 041219
  76. GRB041223: decay of the afterglow
  77. GRB 041224: near-infrared observations with REM
  78. GRB 041223: XRT afterglow spectrum and light curve
  79. GRB 041223 Fluence measured by Swift-BAT
  80. GRB041223: optical and NIR observations with REM
  81. GRB 041219: TAROT optical observations
  82. GRB 041218: TAROT optical observations
  83. GRB 041223: J-band observations of the afterglow
  84. GRB 041223: Detection of Optical Transient with LCO40
  85. GRB 041219c: PROMPT Observations
  86. GRB 041218: optical observations
  87. GRB 041219: Second Epoch WSRT Radio Observations
  88. GRB 041219: WSRT Radio Afterglow Detection
  89. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  90. GRB 041218: Optical observations
  91. GRB 041219 : optical follow-up observations
  92. Deep RAPTOR observations during GRB 041219
  93. GRB 041218 Optical Observations
  94. GRB 041219 Optical Observations
  95. GRB041219c: Third Burst in One Day from Swift-BAT
  96. GRB041219: Optical Afterglow Detection
  97. GRB041219: Continued NIR Observations
  98. GRB 041219 ,optical observation
  99. GRB 041219: Radio Afterglow Detection
  100. GRB 041218 : Radio Observations

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