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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"

45409 results found.

  1. GRB050117: Refined XRT position
  2. GRB050117: MASTER optical observations
  3. MASTER:GRB050117 SWIFT
  4. GRB050117: Swift-BAT detection of a long multi-peaked burst
  5. GRB050117: Swift XRT Position
  6. SGR 1806-20: RXTE/PCA pulse frequency during flare
  7. Triangulation of Short Hard GRB050112 (large error box)
  8. SGR 1806-20: Further low frequency GMRT results
  9. SGR1806-20: Swift-BAT observations of two additional bursts
  10. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  11. Further VLA observations of SGR 1806-20
  12. SGR 1806-20 and extragalactic short-duration GRBs
  13. Further ATCA observations of SGR 1806-20
  14. Fourth Epoch VLA observations of SGR 1806-20
  15. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  16. SGR 1806-20: Temporal and Spectral behavior of radio transient
  17. ATCA observations of SGR 1806-20
  18. SGR 1806-20, RHESSI observations of the 041227 giant flare
  19. Third epoch observations of SGR 1806-20 with VLA
  20. Second Epoch VLA observations of SGR 1806-20
  21. Second-epoch VLA observations of SGR 1806-20
  22. SGR1806: Detection of a Sudden Ionospheric Disturbance
  23. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  24. VLA observations of SGR 1806-20
  25. SGR1806 VLA Observations
  26. VLA observations of SGR 1806-20
  27. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  28. GRB 041217: Optical observations
  29. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  30. GRB041219, early time observations
  31. Detection of the SGR 1806-20 giant outburst back-scattered by the
  32. The giant outburst from SGR 1806-20
  33. IPN localization of giant flare from SGR1806-20
  34. Giant flare from SGR 1806-20 detected by INTEGRAL
  35. GRB041228: ROTSE-III Optical Observations
  36. GRB041228: Swift-BAT detection of a burst
  37. GRB041219; RXTE ASM Observations
  38. NIR Observations of GRB 041219
  39. GRB041226: ROTSE-III Optical Observations
  40. GRB041226: Swift-BAT detection of a burst
  41. GRB041223: decay of the afterglow
  42. GRB041224: ROTSE-III Optical Observations
  43. GRB 041224: near-infrared observations with REM
  44. GRB 041223: XRT afterglow spectrum and light curve
  45. GRB 041223 Fluence measured by Swift-BAT
  46. GRB041224: Swift-BAT detection of a soft burst
  47. GRB041223: optical and NIR observations with REM
  48. Swift-BAT Time History of GRB041219
  49. GRB 041219: TAROT optical observations
  50. GRB 041218: TAROT optical observations
  51. GRB 041223: J-band observations of the afterglow
  52. GRB 041223: Detection of Optical Transient with LCO40
  53. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  54. GRB 041219c: PROMPT Observations
  55. GRB041223: ROTSE-III Optical Observations
  56. GRB041223: Swift-BAT detection of a bright long burst
  57. GRB 041218: optical observations
  58. Very high activity of SGR 1806-20
  59. GRB 041219: Second Epoch WSRT Radio Observations
  60. GRB 041219: WSRT Radio Afterglow Detection
  61. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  62. GRB 041218: Optical observations
  63. GRB 041219 : optical follow-up observations
  64. GRB041220: Swift-BAT burst
  65. Deep RAPTOR observations during GRB 041219
  66. GRB 041218 Optical Observations
  67. GRB 041219 Optical Observations
  68. GRB041219c: Third Burst in One Day from Swift-BAT
  69. GRB041219: Optical Afterglow Detection
  70. GRB041219: Continued NIR Observations
  71. GRB041219b: A Swift-BAT burst
  72. GRB 041219 ,optical observation
  73. GRB 041219: Radio Afterglow Detection
  74. GRB 041218 : Radio Observations
  75. GRB 041218: R-band optical observations
  76. GRB041218: Liverpool Telescope optical observations
  77. GRB041218: optical observations
  78. GRB041219: Confirmed NIR Afterglow
  79. GRB041218: Continued P60 Optical Observations
  80. Swift-BAT detection of the bright long burst GRB041219
  81. GRB 041218: Optical Observation
  82. GRB 041219: Infrared Afterglow Candidate
  83. GRB041219, BVRcIc field calibration
  84. GRB 041219: Infrared Afterglow Candidate
  85. GRB041218, BVRcIc field calibration
  86. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  87. GRB041219: P60 Optical Observations
  88. GRB 041219 - A long GRB detected by INTEGRAL
  89. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  90. GRB 041217: PROMPT Observations
  91. GRB041218: optical observations
  92. GRB041217: optical limit 30 min after GRB
  93. GRB 041218; optical candidate
  94. GRB 041218: Optical observations
  95. GRB 041217: LCO40 Optical Observations and Possible Candidates
  96. GRB 041218 - A long GRB detected by integral
  97. GRB041217: Optical Observations
  98. GRB041217: NIR and optical observations with REM
  99. GRB041217: P60 Optical Observations
  100. GRB041217: Infrared Observations

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