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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"
  1. GRB 050215b: Swift XRT Observations
  2. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  3. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  4. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  5. GRB 050215b, BOOTES-1B optical limit
  6. GRB050215B: ROTSE-III optical observations
  7. GRB050215A: ROTSE-III Optical Observations
  8. GRB050209: TAROT optical observations
  9. GRB 050209(=U11568): Duration and spectrum
  10. short/hard GRB 050202, optical observations
  11. GRB050209: REM optical observations
  12. GRB 050209 I-band observation
  13. GRB 050209 Optical observations
  14. GRB050209: P60 Optical Observations
  15. GRB050209 (=U11568): A Long GRB Detected by HETE
  16. GRB 050209: Optical observation
  17. GRB 050128: Radio observations
  18. Further analysis of the short Swift-BAT GRB 050202
  19. GRB 050202: Second epoch radio observations
  20. GRB 050129: Optical observations
  21. GRB050202: Radio Observations
  22. GRB 050202: Optical observations with LCO40
  23. GRB 050202: Short burst detected by Swift-BAT
  24. GRB 050128 Optical observation with REM
  25. GRB 050129: a weak long GRB detected with INTEGRAL
  26. SGR1806-20: Swift-BAT detection of a large normal burst
  27. GRB050128: Faulkes Telescope South observations
  28. GRB 050124: Radio Observations
  29. GRB 050128: near-infrared observations with REM
  30. GRB050128,optical observations
  31. GRB 050126: A NIR afterglow candidate in the revised XRT error circle
  32. GRB050126: Updated Swift XRT Position
  33. SGR 1806-20: GMRT results at 240 MHz band.
  34. SGR 1806-20: low frequency GMRT results of 2005 Jan 16.
  35. GRB 050126: Radio Observations
  36. GRB050128 Swift-BAT observations
  37. GRB 050128: Swift XRT prompt afterglow position
  38. HETE #3667: P60 Observations
  39. GRB 050124: K-band afterglow observations
  40. GRB050126: MASTER optical limit for KECK OT
  41. GRB050126: Burst Parameters Measured by BAT
  42. GRB050126: MASTER optical observations
  43. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  44. GRB 050126: Prompt XRT detection and localization
  45. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  46. GRB050124: No Swift UVOT Detection of Afterglow Emission
  47. GRB 050124, SMARTS optical/IR observations
  48. GRB 050117a: Radio Observations
  49. GRB 050124 I-band observation
  50. GRB 050124: NIR Candidates from Keck/NIRC
  51. GRB050124,optical observation
  52. GRB 050124 : Lulin R-band follow-up observation
  53. GRB050124: Updated Swift XRT Position and Fluxes
  54. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  55. GRB050124: Refined BAT position, spectral and fluence information
  56. GRB050124: Swift-BAT position of a double-peaked burst
  57. GRB 050123 : I-band follow-up observation
  58. GRB050123: optical limit 1.8h before GRB
  59. GRB050123,optical observation
  60. GRB 050123: KAIT observations
  61. GRB050123: P60 Observations
  62. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  63. CFHTLS optical transient unlikely to be a GRB
  64. Unusual optical transient (GRB ???)
  65. GRB050117a: Radio Observations
  66. GRB050117a: Refined analysis
  67. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  68. GRB050117: Palomar WIRC Ks-band observations
  69. GRB050117b: Swift-BAT detection of a weak burst
  70. GRB050117: optical observation
  71. GRB 050117, I-band observations
  72. GRB 050117: Optical observation
  73. GRB050117: Refined XRT position
  74. GRB050117: MASTER optical observations
  75. MASTER:GRB050117 SWIFT
  76. GRB050117: Swift-BAT detection of a long multi-peaked burst
  77. GRB050117: Swift XRT Position
  78. SGR 1806-20: RXTE/PCA pulse frequency during flare
  79. Triangulation of Short Hard GRB050112 (large error box)
  80. SGR 1806-20: Further VLA Observations
  81. SGR 1806-20: Further low frequency GMRT results
  82. SGR 1806-20: Further VLA Observations
  83. SGR1806-20: Swift-BAT observations of two additional bursts
  84. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  85. Further VLA observations of SGR 1806-20
  86. SGR 1806-20 and extragalactic short-duration GRBs
  87. Further ATCA observations of SGR 1806-20
  88. Fourth Epoch VLA observations of SGR 1806-20
  89. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  90. SGR 1806-20: Temporal and Spectral behavior of radio transient
  91. ATCA observations of SGR 1806-20
  92. SGR 1806-20, RHESSI observations of the 041227 giant flare
  93. Third epoch observations of SGR 1806-20 with VLA
  94. Second Epoch VLA observations of SGR 1806-20
  95. Second-epoch VLA observations of SGR 1806-20
  96. SGR1806: Detection of a Sudden Ionospheric Disturbance
  97. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  98. VLA observations of SGR 1806-20
  99. SGR1806 VLA Observations
  100. VLA observations of SGR 1806-20

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