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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"

24887 results found.

  1. GRB 050209 Optical observations
  2. GRB050209: P60 Optical Observations
  3. GRB 050128: Radio observations
  4. Further analysis of the short Swift-BAT GRB 050202
  5. GRB 050202: Short burst detected by Swift-BAT
  6. GRB 050128 Optical observation with REM
  7. SGR1806-20: Swift-BAT detection of a large normal burst
  8. GRB 050128: near-infrared observations with REM
  9. GRB050128,optical observations
  10. GRB050128 Swift-BAT observations
  11. GRB 050128: Swift XRT prompt afterglow position
  12. GRB050126: MASTER optical limit for KECK OT
  13. GRB050126: Burst Parameters Measured by BAT
  14. GRB050126: MASTER optical observations
  15. GRB 050124 I-band observation
  16. GRB050124,optical observation
  17. GRB 050124 : Lulin R-band follow-up observation
  18. GRB050124: Updated Swift XRT Position and Fluxes
  19. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  20. GRB050124: Refined BAT position, spectral and fluence information
  21. GRB 050123 : I-band follow-up observation
  22. GRB050123,optical observation
  23. GRB 050123: KAIT observations
  24. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  25. GRB050117: Refined XRT position
  26. GRB050117: MASTER optical observations
  27. MASTER:GRB050117 SWIFT
  28. GRB050117: Swift XRT Position
  29. Triangulation of Short Hard GRB050112 (large error box)
  30. SGR 1806-20: Further VLA Observations
  31. SGR1806-20: Swift-BAT observations of two additional bursts
  32. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  33. Further VLA observations of SGR 1806-20
  34. SGR 1806-20 and extragalactic short-duration GRBs
  35. Further ATCA observations of SGR 1806-20
  36. Fourth Epoch VLA observations of SGR 1806-20
  37. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  38. ATCA observations of SGR 1806-20
  39. SGR 1806-20, RHESSI observations of the 041227 giant flare
  40. Third epoch observations of SGR 1806-20 with VLA
  41. Second Epoch VLA observations of SGR 1806-20
  42. Second-epoch VLA observations of SGR 1806-20
  43. SGR1806 VLA Observations
  44. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  45. GRB 041217: Optical observations
  46. GRB041228: Swift-BAT detection of a burst
  47. GRB041219; RXTE ASM Observations
  48. NIR Observations of GRB 041219
  49. GRB041226: Swift-BAT detection of a burst
  50. GRB041223: decay of the afterglow
  51. GRB 041224: near-infrared observations with REM
  52. GRB 041223 Fluence measured by Swift-BAT
  53. GRB041223: optical and NIR observations with REM
  54. Swift-BAT Time History of GRB041219
  55. GRB 041219: TAROT optical observations
  56. GRB 041218: TAROT optical observations
  57. GRB 041223: J-band observations of the afterglow
  58. GRB 041219c: PROMPT Observations
  59. GRB041223: Swift-BAT detection of a bright long burst
  60. GRB 041218: optical observations
  61. GRB 041219 : optical follow-up observations
  62. Deep RAPTOR observations during GRB 041219
  63. GRB 041218 Optical Observations
  64. GRB041219: Continued NIR Observations
  65. GRB 041219 ,optical observation
  66. GRB 041219: Radio Afterglow Detection
  67. GRB 041218 : Radio Observations
  68. GRB 041218: R-band optical observations
  69. GRB041218: optical observations
  70. GRB041219: Confirmed NIR Afterglow
  71. Swift-BAT detection of the bright long burst GRB041219
  72. GRB 041219: Infrared Afterglow Candidate
  73. GRB041219, BVRcIc field calibration
  74. GRB 041219: Infrared Afterglow Candidate
  75. GRB041218, BVRcIc field calibration
  76. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  77. GRB 041219 - A long GRB detected by INTEGRAL
  78. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  79. GRB 041217: PROMPT Observations
  80. GRB 041217: LCO40 Optical Observations and Possible Candidates
  81. GRB 041218 - A long GRB detected by integral
  82. GRB041217: NIR and optical observations with REM
  83. GRB041217: Infrared Observations
  84. GRB041217: The First GRB Located On-Board Swift
  85. GRB041211: Faulkes Telescope continued optical monitoring
  86. Optical Transient in Lynx not a GRB
  87. Optical transient (GRB?) in Lynx
  88. GRB041211: RAPTOR observations
  89. GRB041211: Ashra Prototype optical observation
  90. GRB041211, BVRcIc field calibration
  91. GRB041211,optical observation
  92. GRB 041211: Infrared Observations
  93. GRB 041211: KAIT observations
  94. GRB 041211: Optical follow-up in East Asian region
  95. Triangulation of short GRB 041116 (large error box)
  96. GRB 040924: Afterglow Color
  97. GRB 041006: GETS Optical Afterglow Observation
  98. Summary of the recent bursts from SGR 1806-20
  99. GRB 041006: Optical Observations
  100. GRB041006, late-time optical photometry

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