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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').
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"

27392 results found.

  1. GRB050215A: ROTSE-III Optical Observations
  2. GRB050209: TAROT optical observations
  3. GRB 050209(=U11568): Duration and spectrum
  4. GRB050209: REM optical observations
  5. GRB 050209 I-band observation
  6. GRB 050209 Optical observations
  7. GRB050209: P60 Optical Observations
  8. GRB 050128: Radio observations
  9. Further analysis of the short Swift-BAT GRB 050202
  10. GRB 050202: Short burst detected by Swift-BAT
  11. GRB 050128 Optical observation with REM
  12. SGR1806-20: Swift-BAT detection of a large normal burst
  13. GRB 050128: near-infrared observations with REM
  14. GRB050128,optical observations
  15. GRB050128 Swift-BAT observations
  16. GRB 050128: Swift XRT prompt afterglow position
  17. GRB050126: MASTER optical limit for KECK OT
  18. GRB050126: Burst Parameters Measured by BAT
  19. GRB050126: MASTER optical observations
  20. GRB 050124 I-band observation
  21. GRB050124,optical observation
  22. GRB 050124 : Lulin R-band follow-up observation
  23. GRB050124: Updated Swift XRT Position and Fluxes
  24. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  25. GRB050124: Refined BAT position, spectral and fluence information
  26. GRB 050123 : I-band follow-up observation
  27. GRB050123,optical observation
  28. GRB 050123: KAIT observations
  29. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  30. GRB050117: Refined XRT position
  31. GRB050117: MASTER optical observations
  32. MASTER:GRB050117 SWIFT
  33. GRB050117: Swift XRT Position
  34. Triangulation of Short Hard GRB050112 (large error box)
  35. SGR 1806-20: Further VLA Observations
  36. SGR1806-20: Swift-BAT observations of two additional bursts
  37. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  38. Further VLA observations of SGR 1806-20
  39. SGR 1806-20 and extragalactic short-duration GRBs
  40. Further ATCA observations of SGR 1806-20
  41. Fourth Epoch VLA observations of SGR 1806-20
  42. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  43. ATCA observations of SGR 1806-20
  44. SGR 1806-20, RHESSI observations of the 041227 giant flare
  45. Third epoch observations of SGR 1806-20 with VLA
  46. Second Epoch VLA observations of SGR 1806-20
  47. Second-epoch VLA observations of SGR 1806-20
  48. SGR1806 VLA Observations
  49. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  50. GRB 041217: Optical observations
  51. GRB041228: Swift-BAT detection of a burst
  52. GRB041219; RXTE ASM Observations
  53. NIR Observations of GRB 041219
  54. GRB041226: Swift-BAT detection of a burst
  55. GRB041223: decay of the afterglow
  56. GRB 041224: near-infrared observations with REM
  57. GRB 041223 Fluence measured by Swift-BAT
  58. GRB041223: optical and NIR observations with REM
  59. Swift-BAT Time History of GRB041219
  60. GRB 041219: TAROT optical observations
  61. GRB 041218: TAROT optical observations
  62. GRB 041223: J-band observations of the afterglow
  63. GRB 041219c: PROMPT Observations
  64. GRB041223: Swift-BAT detection of a bright long burst
  65. GRB 041218: optical observations
  66. GRB 041219 : optical follow-up observations
  67. Deep RAPTOR observations during GRB 041219
  68. GRB 041218 Optical Observations
  69. GRB041219: Continued NIR Observations
  70. GRB 041219 ,optical observation
  71. GRB 041219: Radio Afterglow Detection
  72. GRB 041218 : Radio Observations
  73. GRB 041218: R-band optical observations
  74. GRB041218: optical observations
  75. GRB041219: Confirmed NIR Afterglow
  76. Swift-BAT detection of the bright long burst GRB041219
  77. GRB 041219: Infrared Afterglow Candidate
  78. GRB041219, BVRcIc field calibration
  79. GRB 041219: Infrared Afterglow Candidate
  80. GRB041218, BVRcIc field calibration
  81. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  82. GRB 041219 - A long GRB detected by INTEGRAL
  83. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  84. GRB 041217: PROMPT Observations
  85. GRB 041217: LCO40 Optical Observations and Possible Candidates
  86. GRB 041218 - A long GRB detected by integral
  87. GRB041217: NIR and optical observations with REM
  88. GRB041217: Infrared Observations
  89. GRB041217: The First GRB Located On-Board Swift
  90. GRB041211: Faulkes Telescope continued optical monitoring
  91. Optical Transient in Lynx not a GRB
  92. Optical transient (GRB?) in Lynx
  93. GRB041211: RAPTOR observations
  94. GRB041211: Ashra Prototype optical observation
  95. GRB041211, BVRcIc field calibration
  96. GRB041211,optical observation
  97. GRB 041211: Infrared Observations
  98. GRB 041211: KAIT observations
  99. GRB 041211: Optical follow-up in East Asian region
  100. Triangulation of short GRB 041116 (large error box)

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