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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"

19875 results found.

  1. GRB 050117a: Radio Observations
  2. GRB050124,optical observation
  3. GRB050124: Updated Swift XRT Position and Fluxes
  4. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  5. GRB050124: Refined BAT position, spectral and fluence information
  6. GRB050124: Swift-BAT position of a double-peaked burst
  7. GRB050117a: Radio Observations
  8. GRB050117a: Refined analysis
  9. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  10. GRB050117b: Swift-BAT detection of a weak burst
  11. GRB050117: optical observation
  12. GRB 050117, I-band observations
  13. GRB 050117: Optical observation
  14. GRB050117: Refined XRT position
  15. GRB050117: MASTER optical observations
  16. MASTER:GRB050117 SWIFT
  17. GRB050117: Swift-BAT detection of a long multi-peaked burst
  18. GRB050117: Swift XRT Position
  19. SGR 1806-20: RXTE/PCA pulse frequency during flare
  20. SGR 1806-20: Further VLA Observations
  21. SGR 1806-20: Further low frequency GMRT results
  22. SGR 1806-20: Further VLA Observations
  23. SGR1806-20: Swift-BAT observations of two additional bursts
  24. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  25. Further VLA observations of SGR 1806-20
  26. SGR 1806-20 and extragalactic short-duration GRBs
  27. Further ATCA observations of SGR 1806-20
  28. Fourth Epoch VLA observations of SGR 1806-20
  29. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  30. SGR 1806-20: Temporal and Spectral behavior of radio transient
  31. ATCA observations of SGR 1806-20
  32. SGR 1806-20, RHESSI observations of the 041227 giant flare
  33. Third epoch observations of SGR 1806-20 with VLA
  34. Second Epoch VLA observations of SGR 1806-20
  35. Second-epoch VLA observations of SGR 1806-20
  36. SGR1806: Detection of a Sudden Ionospheric Disturbance
  37. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  38. VLA observations of SGR 1806-20
  39. SGR1806 VLA Observations
  40. VLA observations of SGR 1806-20
  41. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  42. GRB 041217: Optical observations
  43. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  44. Detection of the SGR 1806-20 giant outburst back-scattered by the
  45. The giant outburst from SGR 1806-20
  46. Giant flare from SGR 1806-20 detected by INTEGRAL
  47. GRB041228: ROTSE-III Optical Observations
  48. GRB041228: Swift-BAT detection of a burst
  49. GRB041219; RXTE ASM Observations
  50. NIR Observations of GRB 041219
  51. GRB041226: ROTSE-III Optical Observations
  52. GRB041226: Swift-BAT detection of a burst
  53. GRB041223: decay of the afterglow
  54. GRB041224: ROTSE-III Optical Observations
  55. GRB 041223: XRT afterglow spectrum and light curve
  56. GRB 041223 Fluence measured by Swift-BAT
  57. GRB041224: Swift-BAT detection of a soft burst
  58. GRB041223: optical and NIR observations with REM
  59. Swift-BAT Time History of GRB041219
  60. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  61. GRB041223: ROTSE-III Optical Observations
  62. GRB041223: Swift-BAT detection of a bright long burst
  63. Very high activity of SGR 1806-20
  64. GRB041220: Swift-BAT burst
  65. GRB 041219 Optical Observations
  66. GRB041219c: Third Burst in One Day from Swift-BAT
  67. GRB041219b: A Swift-BAT burst
  68. Swift-BAT detection of the bright long burst GRB041219
  69. GRB041217: optical limit 30 min after GRB
  70. GRB041217: Optical Observations
  71. GRB041217: NIR and optical observations with REM
  72. GRB041217: P60 Optical Observations
  73. GRB041217: Infrared Observations
  74. GRB041217: The First GRB Located On-Board Swift
  75. Summary of the recent bursts from SGR 1806-20
  76. IBAS GRB Alert # 2034
  77. Bright bursts from SGR1806-20
  78. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  79. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  80. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  81. SGR 1806-20 still active
  82. GRB040916: Optical observations
  83. An intense burst from SGR1806-20
  84. Very bright burst detected from SGR 1806-20
  85. Increase of SGR 1806-20 activity
  86. Bursting activity from SGR 1806-20 detected with IBAS
  87. Ongoing activity of SGR 1806-20
  88. GRB040706:observation at University of Miyazaki
  89. SGR 1806-20: no IR variability of the proposed counterparts
  90. SGR 1806-20, potential NIR counterpart
  91. Activivty of SGR 1806-20
  92. IBAS GRB Alerts n.1785 to 1791
  93. GRB040422: optical and NIR observations at the VLT
  94. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  95. IBAS GRB Alert 1694
  96. IBAS GRB alerts 1679, 1680, 1681
  97. GRB040223, improved XMM position
  98. IBAS results on a burst from SGR1806-20
  99. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  100. IBAS alert 1180 refers to a burst from SGR 1806-20

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