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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').
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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"

11756 results found.

  1. GRB 050319: NIR afterglow candidate
  2. GRB 050319:Near IR afterglow
  3. GRB050319: BR optical photometry
  4. GRB 050319: Optical observation
  5. GRB050223: analysis of the XMM-Newton observation
  6. GRB050315: Radio afterglow
  7. GRB 050315: Absorption redshift
  8. GRB 050315: Optical afterglow identification
  9. GRB 050315: Swift XRT Position
  10. Swift-BAT detection of GRB 050315
  11. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  12. GRB 050306: R-band observations
  13. Swift trigger 107518: optical observation
  14. Ongoing activity of SGR 1806-20 after the giant flare
  15. GRB050215B: Late-Time Swift UVOT Observations
  16. INTEGRAL detection of GRB 050223
  17. GRB 050223 : Planned XMM-Newton observation
  18. GRB050223: ROTSE-III Optical Observations
  19. GRB 050219a: Optical observations from LCO
  20. GRB 050215b: Swift XRT Source Variability
  21. GRB 050215b : Lulin follow-up observation
  22. GRB050215B: ROTSE-III optical observations
  23. GRB050215A: ROTSE-III Optical Observations
  24. short/hard GRB 050202, optical observations
  25. GRB 050129: a weak long GRB detected with INTEGRAL
  26. SGR1806-20: Swift-BAT detection of a large normal burst
  27. SGR 1806-20: GMRT results at 240 MHz band.
  28. SGR 1806-20: low frequency GMRT results of 2005 Jan 16.
  29. GRB 050128: Swift XRT prompt afterglow position
  30. GRB050126: Burst Parameters Measured by BAT
  31. GRB 050124 : Lulin R-band follow-up observation
  32. GRB050124: Refined BAT position, spectral and fluence information
  33. Unusual optical transient (GRB ???)
  34. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  35. GRB050117b: Swift-BAT detection of a weak burst
  36. GRB050117: optical observation
  37. GRB050117: Refined XRT position
  38. GRB050117: MASTER optical observations
  39. MASTER:GRB050117 SWIFT
  40. SGR 1806-20: RXTE/PCA pulse frequency during flare
  41. Triangulation of Short Hard GRB050112 (large error box)
  42. SGR 1806-20: Further VLA Observations
  43. SGR 1806-20: Further low frequency GMRT results
  44. SGR 1806-20: Further VLA Observations
  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. Further ATCA observations of SGR 1806-20
  50. Fourth Epoch VLA observations of SGR 1806-20
  51. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  52. SGR 1806-20: Temporal and Spectral behavior of radio transient
  53. ATCA observations of SGR 1806-20
  54. SGR 1806-20, RHESSI observations of the 041227 giant flare
  55. Third epoch observations of SGR 1806-20 with VLA
  56. Second Epoch VLA observations of SGR 1806-20
  57. Second-epoch VLA observations of SGR 1806-20
  58. SGR1806: Detection of a Sudden Ionospheric Disturbance
  59. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  60. VLA observations of SGR 1806-20
  61. SGR1806 VLA Observations
  62. VLA observations of SGR 1806-20
  63. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  64. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  65. Detection of the SGR 1806-20 giant outburst back-scattered by the
  66. The giant outburst from SGR 1806-20
  67. IPN localization of giant flare from SGR1806-20
  68. Giant flare from SGR 1806-20 detected by INTEGRAL
  69. NIR Observations of GRB 041219
  70. GRB041226: ROTSE-III Optical Observations
  71. GRB041226: Swift-BAT detection of a burst
  72. GRB041224: ROTSE-III Optical Observations
  73. GRB041224: Swift-BAT detection of a soft burst
  74. GRB 041223: Detection of Optical Transient with LCO40
  75. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  76. GRB041223: ROTSE-III Optical Observations
  77. Very high activity of SGR 1806-20
  78. GRB 041219: WSRT Radio Afterglow Detection
  79. GRB 041219 : optical follow-up observations
  80. GRB041219c: Third Burst in One Day from Swift-BAT
  81. GRB041219: Optical Afterglow Detection
  82. GRB041218: optical observations
  83. GRB041219: P60 Optical Observations
  84. GRB 041219 - A long GRB detected by INTEGRAL
  85. GRB 041218; optical candidate
  86. GRB 041218: Optical observations
  87. GRB 041218 - A long GRB detected by integral
  88. GRB041217: The First GRB Located On-Board Swift
  89. GRB041211: Continued P60 Observations
  90. GRB 041211: Infrared Observations
  91. GRB 041211: KAIT observations
  92. GRB 041211: Optical follow-up in East Asian region
  93. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  94. GRB041015: Near-Infrared observations
  95. GRB 041006: GETS Optical Afterglow Observation
  96. Summary of the recent bursts from SGR 1806-20
  97. GRB041015, optical observation in CrAO
  98. IBAS GRB Alert # 2034
  99. Bright bursts from SGR1806-20
  100. GRB041016: MASTER: Optical observations

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