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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').
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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"

38573 results found.

  1. SGR 1806-20: Further VLA Observations
  2. SGR1806-20: Swift-BAT observations of two additional bursts
  3. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  4. Further VLA observations of SGR 1806-20
  5. SGR 1806-20 and extragalactic short-duration GRBs
  6. Further ATCA observations of SGR 1806-20
  7. Fourth Epoch VLA observations of SGR 1806-20
  8. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  9. ATCA observations of SGR 1806-20
  10. SGR 1806-20, RHESSI observations of the 041227 giant flare
  11. Third epoch observations of SGR 1806-20 with VLA
  12. Second Epoch VLA observations of SGR 1806-20
  13. Second-epoch VLA observations of SGR 1806-20
  14. SGR1806: Detection of a Sudden Ionospheric Disturbance
  15. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  16. VLA observations of SGR 1806-20
  17. SGR1806 VLA Observations
  18. VLA observations of SGR 1806-20
  19. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  20. GRB 041217: Optical observations
  21. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  22. GRB041219, early time observations
  23. Detection of the SGR 1806-20 giant outburst back-scattered by the
  24. The giant outburst from SGR 1806-20
  25. IPN localization of giant flare from SGR1806-20
  26. Giant flare from SGR 1806-20 detected by INTEGRAL
  27. GRB041228: ROTSE-III Optical Observations
  28. GRB041228: Swift-BAT detection of a burst
  29. GRB041219; RXTE ASM Observations
  30. NIR Observations of GRB 041219
  31. GRB041226: ROTSE-III Optical Observations
  32. GRB041226: Swift-BAT detection of a burst
  33. GRB041223: decay of the afterglow
  34. GRB041224: ROTSE-III Optical Observations
  35. GRB 041224: near-infrared observations with REM
  36. GRB 041223: XRT afterglow spectrum and light curve
  37. GRB 041223 Fluence measured by Swift-BAT
  38. GRB041224: Swift-BAT detection of a soft burst
  39. GRB041223: optical and NIR observations with REM
  40. Swift-BAT Time History of GRB041219
  41. GRB 041223: J-band observations of the afterglow
  42. GRB 041223: Detection of Optical Transient with LCO40
  43. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  44. GRB 041219c: PROMPT Observations
  45. GRB041223: ROTSE-III Optical Observations
  46. GRB041223: Swift-BAT detection of a bright long burst
  47. GRB 041218: optical observations
  48. Very high activity of SGR 1806-20
  49. GRB 041219: Second Epoch WSRT Radio Observations
  50. GRB 041219: WSRT Radio Afterglow Detection
  51. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  52. GRB 041219 : optical follow-up observations
  53. GRB041220: Swift-BAT burst
  54. Deep RAPTOR observations during GRB 041219
  55. GRB 041218 Optical Observations
  56. GRB 041219 Optical Observations
  57. GRB041219c: Third Burst in One Day from Swift-BAT
  58. GRB041219: Optical Afterglow Detection
  59. GRB041219: Continued NIR Observations
  60. GRB041219b: A Swift-BAT burst
  61. GRB 041219 ,optical observation
  62. GRB 041219: Radio Afterglow Detection
  63. GRB 041218 : Radio Observations
  64. GRB 041218: R-band optical observations
  65. GRB041218: Liverpool Telescope optical observations
  66. GRB041218: optical observations
  67. GRB041219: Confirmed NIR Afterglow
  68. GRB041218: Continued P60 Optical Observations
  69. Swift-BAT detection of the bright long burst GRB041219
  70. GRB 041219: Infrared Afterglow Candidate
  71. GRB041219, BVRcIc field calibration
  72. GRB 041219: Infrared Afterglow Candidate
  73. GRB041218, BVRcIc field calibration
  74. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  75. GRB041219: P60 Optical Observations
  76. GRB 041219 - A long GRB detected by INTEGRAL
  77. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  78. GRB 041217: PROMPT Observations
  79. GRB041217: optical limit 30 min after GRB
  80. GRB 041218: Optical observations
  81. GRB 041217: LCO40 Optical Observations and Possible Candidates
  82. GRB 041218 - A long GRB detected by integral
  83. GRB041217: Optical Observations
  84. GRB041217: NIR and optical observations with REM
  85. GRB041217: P60 Optical Observations
  86. GRB041217: Infrared Observations
  87. GRB041217: The First GRB Located On-Board Swift
  88. GRB041211: Faulkes Telescope continued optical monitoring
  89. Optical Transient in Lynx not a GRB
  90. Optical transient (GRB?) in Lynx
  91. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  92. GRB041211: Continued P60 Observations
  93. GRB041211: RAPTOR observations
  94. GRB041211: Ashra Prototype optical observation
  95. GRB041211, Faulkes Telescope optical observation
  96. GRB041211, BVRcIc field calibration
  97. GRB041211,optical observation
  98. GRB 041211: Infrared Observations
  99. GRB 041211: KAIT observations
  100. GRB 041211: Optical follow-up in East Asian region

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