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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"

32531 results found.

  1. GRB050209: P60 Optical Observations
  2. GRB050209 (=U11568): A Long GRB Detected by HETE
  3. GRB 050128: Radio observations
  4. Further analysis of the short Swift-BAT GRB 050202
  5. GRB 050202: Second epoch radio observations
  6. GRB 050129: Optical observations
  7. GRB050202: Radio Observations
  8. GRB 050202: Optical observations with LCO40
  9. GRB 050128 Optical observation with REM
  10. GRB050128: Faulkes Telescope South observations
  11. GRB 050124: Radio Observations
  12. GRB 050128: near-infrared observations with REM
  13. GRB050128,optical observations
  14. GRB 050126: A NIR afterglow candidate in the revised XRT error circle
  15. GRB 050126: Radio Observations
  16. GRB050128 Swift-BAT observations
  17. GRB 050128: Swift XRT prompt afterglow position
  18. GRB 050124: K-band afterglow observations
  19. GRB050126: MASTER optical limit for KECK OT
  20. GRB050126: Burst Parameters Measured by BAT
  21. GRB050126: MASTER optical observations
  22. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  23. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  24. GRB050124: No Swift UVOT Detection of Afterglow Emission
  25. GRB 050124, SMARTS optical/IR observations
  26. GRB 050117a: Radio Observations
  27. GRB 050124 I-band observation
  28. GRB 050124: NIR Candidates from Keck/NIRC
  29. GRB050124,optical observation
  30. GRB 050124 : Lulin R-band follow-up observation
  31. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  32. GRB050124: Refined BAT position, spectral and fluence information
  33. GRB 050123 : I-band follow-up observation
  34. GRB050123: optical limit 1.8h before GRB
  35. GRB 050123: KAIT observations
  36. GRB050123: P60 Observations
  37. CFHTLS optical transient unlikely to be a GRB
  38. GRB050117a: Radio Observations
  39. GRB050117a: Refined analysis
  40. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  41. GRB050117: Palomar WIRC Ks-band observations
  42. GRB050117: optical observation
  43. GRB 050117, I-band observations
  44. GRB 050117: Optical observation
  45. GRB050117: Refined XRT position
  46. GRB050117: MASTER optical observations
  47. MASTER:GRB050117 SWIFT
  48. GRB050117: Swift-BAT detection of a long multi-peaked burst
  49. SGR 1806-20: RXTE/PCA pulse frequency during flare
  50. SGR 1806-20: Further low frequency GMRT results
  51. SGR1806-20: Swift-BAT observations of two additional bursts
  52. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  53. Further VLA observations of SGR 1806-20
  54. SGR 1806-20 and extragalactic short-duration GRBs
  55. Fourth Epoch VLA observations of SGR 1806-20
  56. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  57. SGR 1806-20: Temporal and Spectral behavior of radio transient
  58. ATCA observations of SGR 1806-20
  59. SGR 1806-20, RHESSI observations of the 041227 giant flare
  60. Third epoch observations of SGR 1806-20 with VLA
  61. Second Epoch VLA observations of SGR 1806-20
  62. Second-epoch VLA observations of SGR 1806-20
  63. SGR1806: Detection of a Sudden Ionospheric Disturbance
  64. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  65. VLA observations of SGR 1806-20
  66. SGR1806 VLA Observations
  67. VLA observations of SGR 1806-20
  68. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  69. GRB 041217: Optical observations
  70. GRB041219, early time observations
  71. The giant outburst from SGR 1806-20
  72. IPN localization of giant flare from SGR1806-20
  73. GRB041228: ROTSE-III Optical Observations
  74. GRB041219; RXTE ASM Observations
  75. NIR Observations of GRB 041219
  76. GRB041226: ROTSE-III Optical Observations
  77. GRB041223: decay of the afterglow
  78. GRB041224: ROTSE-III Optical Observations
  79. GRB 041224: near-infrared observations with REM
  80. GRB 041223: XRT afterglow spectrum and light curve
  81. GRB 041223 Fluence measured by Swift-BAT
  82. GRB041223: optical and NIR observations with REM
  83. Swift-BAT Time History of GRB041219
  84. GRB 041219: TAROT optical observations
  85. GRB 041223: J-band observations of the afterglow
  86. GRB 041223: Detection of Optical Transient with LCO40
  87. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  88. GRB 041219c: PROMPT Observations
  89. GRB041223: ROTSE-III Optical Observations
  90. GRB 041218: optical observations
  91. Very high activity of SGR 1806-20
  92. GRB 041219: Second Epoch WSRT Radio Observations
  93. GRB 041219: WSRT Radio Afterglow Detection
  94. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  95. GRB 041218: Optical observations
  96. GRB 041219 : optical follow-up observations
  97. Deep RAPTOR observations during GRB 041219
  98. GRB 041218 Optical Observations
  99. GRB 041219 Optical Observations
  100. GRB041219: Optical Afterglow Detection

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