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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"

32722 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: Burst Parameters Measured by BAT
  12. GRB050126: MASTER optical observations
  13. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  14. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  15. GRB050124: No Swift UVOT Detection of Afterglow Emission
  16. GRB 050124, SMARTS optical/IR observations
  17. GRB 050117a: Radio Observations
  18. GRB 050124 I-band observation
  19. GRB 050124: NIR Candidates from Keck/NIRC
  20. GRB050124,optical observation
  21. GRB 050124 : Lulin R-band follow-up observation
  22. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  23. GRB050124: Refined BAT position, spectral and fluence information
  24. GRB 050123 : I-band follow-up observation
  25. GRB050123: optical limit 1.8h before GRB
  26. GRB 050123: KAIT observations
  27. GRB050123: P60 Observations
  28. CFHTLS optical transient unlikely to be a GRB
  29. GRB050117a: Radio Observations
  30. GRB050117a: Refined analysis
  31. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  32. GRB050117: Palomar WIRC Ks-band observations
  33. GRB050117: optical observation
  34. GRB 050117, I-band observations
  35. GRB 050117: Optical observation
  36. GRB050117: Refined XRT position
  37. GRB050117: MASTER optical observations
  38. MASTER:GRB050117 SWIFT
  39. GRB050117: Swift-BAT detection of a long multi-peaked burst
  40. SGR 1806-20: RXTE/PCA pulse frequency during flare
  41. SGR 1806-20: Further low frequency GMRT results
  42. SGR1806-20: Swift-BAT observations of two additional bursts
  43. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  44. Further VLA observations of SGR 1806-20
  45. SGR 1806-20 and extragalactic short-duration GRBs
  46. Fourth Epoch VLA observations of SGR 1806-20
  47. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  48. SGR 1806-20: Temporal and Spectral behavior of radio transient
  49. ATCA observations of SGR 1806-20
  50. SGR 1806-20, RHESSI observations of the 041227 giant flare
  51. Third epoch observations of SGR 1806-20 with VLA
  52. Second Epoch VLA observations of SGR 1806-20
  53. Second-epoch VLA observations of SGR 1806-20
  54. SGR1806: Detection of a Sudden Ionospheric Disturbance
  55. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  56. VLA observations of SGR 1806-20
  57. SGR1806 VLA Observations
  58. VLA observations of SGR 1806-20
  59. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  60. GRB 041217: Optical observations
  61. GRB041219, early time observations
  62. The giant outburst from SGR 1806-20
  63. IPN localization of giant flare from SGR1806-20
  64. GRB041228: ROTSE-III Optical Observations
  65. GRB041219; RXTE ASM Observations
  66. NIR Observations of GRB 041219
  67. GRB041226: ROTSE-III Optical Observations
  68. GRB041223: decay of the afterglow
  69. GRB041224: ROTSE-III Optical Observations
  70. GRB 041224: near-infrared observations with REM
  71. GRB 041223: XRT afterglow spectrum and light curve
  72. GRB 041223 Fluence measured by Swift-BAT
  73. GRB041223: optical and NIR observations with REM
  74. Swift-BAT Time History of GRB041219
  75. GRB 041219: TAROT optical observations
  76. GRB 041223: J-band observations of the afterglow
  77. GRB 041223: Detection of Optical Transient with LCO40
  78. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  79. GRB 041219c: PROMPT Observations
  80. GRB041223: ROTSE-III Optical Observations
  81. GRB 041218: optical observations
  82. Very high activity of SGR 1806-20
  83. GRB 041219: Second Epoch WSRT Radio Observations
  84. GRB 041219: WSRT Radio Afterglow Detection
  85. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  86. GRB 041218: Optical observations
  87. GRB 041219 : optical follow-up observations
  88. Deep RAPTOR observations during GRB 041219
  89. GRB 041218 Optical Observations
  90. GRB 041219 Optical Observations
  91. GRB041219: Optical Afterglow Detection
  92. GRB041219: Continued NIR Observations
  93. GRB 041219: Radio Afterglow Detection
  94. GRB 041218 : Radio Observations
  95. GRB 041218: R-band optical observations
  96. GRB041218: Liverpool Telescope optical observations
  97. GRB041218: optical observations
  98. GRB041219: Confirmed NIR Afterglow
  99. Swift-BAT detection of the bright long burst GRB041219
  100. GRB 041218: Optical Observation

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