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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"

32725 results found.

  1. GRB050202: Radio Observations
  2. GRB 050202: Optical observations with LCO40
  3. GRB 050128 Optical observation with REM
  4. GRB050128: Faulkes Telescope South observations
  5. GRB 050124: Radio Observations
  6. GRB 050128: near-infrared observations with REM
  7. GRB050128,optical observations
  8. GRB 050126: A NIR afterglow candidate in the revised XRT error circle
  9. GRB 050126: Radio Observations
  10. GRB050128 Swift-BAT observations
  11. GRB 050128: Swift XRT prompt afterglow position
  12. GRB 050124: K-band afterglow observations
  13. GRB050126: MASTER optical limit for KECK OT
  14. GRB050126: Burst Parameters Measured by BAT
  15. GRB050126: MASTER optical observations
  16. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  17. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  18. GRB050124: No Swift UVOT Detection of Afterglow Emission
  19. GRB 050124, SMARTS optical/IR observations
  20. GRB 050117a: Radio Observations
  21. GRB 050124 I-band observation
  22. GRB 050124: NIR Candidates from Keck/NIRC
  23. GRB050124,optical observation
  24. GRB 050124 : Lulin R-band follow-up observation
  25. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  26. GRB050124: Refined BAT position, spectral and fluence information
  27. GRB 050123 : I-band follow-up observation
  28. GRB050123: optical limit 1.8h before GRB
  29. GRB 050123: KAIT observations
  30. GRB050123: P60 Observations
  31. CFHTLS optical transient unlikely to be a GRB
  32. GRB050117a: Radio Observations
  33. GRB050117a: Refined analysis
  34. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  35. GRB050117: Palomar WIRC Ks-band observations
  36. GRB050117: optical observation
  37. GRB 050117, I-band observations
  38. GRB 050117: Optical observation
  39. GRB050117: Refined XRT position
  40. GRB050117: MASTER optical observations
  41. MASTER:GRB050117 SWIFT
  42. GRB050117: Swift-BAT detection of a long multi-peaked burst
  43. SGR 1806-20: RXTE/PCA pulse frequency during flare
  44. SGR 1806-20: Further low frequency GMRT results
  45. SGR1806-20: Swift-BAT observations of two additional bursts
  46. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  47. Further VLA observations of SGR 1806-20
  48. SGR 1806-20 and extragalactic short-duration GRBs
  49. Fourth Epoch VLA observations of SGR 1806-20
  50. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  51. SGR 1806-20: Temporal and Spectral behavior of radio transient
  52. ATCA observations of SGR 1806-20
  53. SGR 1806-20, RHESSI observations of the 041227 giant flare
  54. Third epoch observations of SGR 1806-20 with VLA
  55. Second Epoch VLA observations of SGR 1806-20
  56. Second-epoch VLA observations of SGR 1806-20
  57. SGR1806: Detection of a Sudden Ionospheric Disturbance
  58. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  59. VLA observations of SGR 1806-20
  60. SGR1806 VLA Observations
  61. VLA observations of SGR 1806-20
  62. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  63. GRB 041217: Optical observations
  64. GRB041219, early time observations
  65. The giant outburst from SGR 1806-20
  66. IPN localization of giant flare from SGR1806-20
  67. GRB041228: ROTSE-III Optical Observations
  68. GRB041219; RXTE ASM Observations
  69. NIR Observations of GRB 041219
  70. GRB041226: ROTSE-III Optical Observations
  71. GRB041223: decay of the afterglow
  72. GRB041224: ROTSE-III Optical Observations
  73. GRB 041224: near-infrared observations with REM
  74. GRB 041223: XRT afterglow spectrum and light curve
  75. GRB 041223 Fluence measured by Swift-BAT
  76. GRB041223: optical and NIR observations with REM
  77. Swift-BAT Time History of GRB041219
  78. GRB 041219: TAROT optical observations
  79. GRB 041223: J-band observations of the afterglow
  80. GRB 041223: Detection of Optical Transient with LCO40
  81. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  82. GRB 041219c: PROMPT Observations
  83. GRB041223: ROTSE-III Optical Observations
  84. GRB 041218: optical observations
  85. Very high activity of SGR 1806-20
  86. GRB 041219: Second Epoch WSRT Radio Observations
  87. GRB 041219: WSRT Radio Afterglow Detection
  88. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  89. GRB 041218: Optical observations
  90. GRB 041219 : optical follow-up observations
  91. Deep RAPTOR observations during GRB 041219
  92. GRB 041218 Optical Observations
  93. GRB 041219 Optical Observations
  94. GRB041219: Optical Afterglow Detection
  95. GRB041219: Continued NIR Observations
  96. GRB 041219: Radio Afterglow Detection
  97. GRB 041218 : Radio Observations
  98. GRB 041218: R-band optical observations
  99. GRB041218: Liverpool Telescope optical observations
  100. GRB041218: optical observations

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