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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"

32689 results found.

  1. GRB 050117, I-band observations
  2. GRB 050117: Optical observation
  3. GRB050117: Refined XRT position
  4. GRB050117: MASTER optical observations
  5. MASTER:GRB050117 SWIFT
  6. GRB050117: Swift-BAT detection of a long multi-peaked burst
  7. SGR 1806-20: RXTE/PCA pulse frequency during flare
  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. Fourth Epoch VLA observations of SGR 1806-20
  14. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  15. SGR 1806-20: Temporal and Spectral behavior of radio transient
  16. ATCA observations of SGR 1806-20
  17. SGR 1806-20, RHESSI observations of the 041227 giant flare
  18. Third epoch observations of SGR 1806-20 with VLA
  19. Second Epoch VLA observations of SGR 1806-20
  20. Second-epoch VLA observations of SGR 1806-20
  21. SGR1806: Detection of a Sudden Ionospheric Disturbance
  22. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  23. VLA observations of SGR 1806-20
  24. SGR1806 VLA Observations
  25. VLA observations of SGR 1806-20
  26. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  27. GRB 041217: Optical observations
  28. GRB041219, early time observations
  29. The giant outburst from SGR 1806-20
  30. IPN localization of giant flare from SGR1806-20
  31. GRB041228: ROTSE-III Optical Observations
  32. GRB041219; RXTE ASM Observations
  33. NIR Observations of GRB 041219
  34. GRB041226: ROTSE-III Optical Observations
  35. GRB041223: decay of the afterglow
  36. GRB041224: ROTSE-III Optical Observations
  37. GRB 041224: near-infrared observations with REM
  38. GRB 041223: XRT afterglow spectrum and light curve
  39. GRB 041223 Fluence measured by Swift-BAT
  40. GRB041223: optical and NIR observations with REM
  41. Swift-BAT Time History of GRB041219
  42. GRB 041219: TAROT optical observations
  43. GRB 041223: J-band observations of the afterglow
  44. GRB 041223: Detection of Optical Transient with LCO40
  45. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  46. GRB 041219c: PROMPT Observations
  47. GRB041223: ROTSE-III Optical Observations
  48. GRB 041218: optical observations
  49. Very high activity of SGR 1806-20
  50. GRB 041219: Second Epoch WSRT Radio Observations
  51. GRB 041219: WSRT Radio Afterglow Detection
  52. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  53. GRB 041218: Optical observations
  54. GRB 041219 : optical follow-up observations
  55. Deep RAPTOR observations during GRB 041219
  56. GRB 041218 Optical Observations
  57. GRB 041219 Optical Observations
  58. GRB041219: Optical Afterglow Detection
  59. GRB041219: Continued NIR Observations
  60. GRB 041219: Radio Afterglow Detection
  61. GRB 041218 : Radio Observations
  62. GRB 041218: R-band optical observations
  63. GRB041218: Liverpool Telescope optical observations
  64. GRB041218: optical observations
  65. GRB041219: Confirmed NIR Afterglow
  66. Swift-BAT detection of the bright long burst GRB041219
  67. GRB 041218: Optical Observation
  68. GRB 041219: Infrared Afterglow Candidate
  69. GRB041219, BVRcIc field calibration
  70. GRB 041219: Infrared Afterglow Candidate
  71. GRB041218, BVRcIc field calibration
  72. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  73. GRB 041217: PROMPT Observations
  74. GRB041218: optical observations
  75. GRB041217: optical limit 30 min after GRB
  76. GRB 041218; optical candidate
  77. GRB 041218: Optical observations
  78. GRB 041217: LCO40 Optical Observations and Possible Candidates
  79. GRB041217: Optical Observations
  80. GRB041217: NIR and optical observations with REM
  81. GRB041217: Infrared Observations
  82. GRB041217: The First GRB Located On-Board Swift
  83. GRB041211: Faulkes Telescope continued optical monitoring
  84. Optical Transient in Lynx not a GRB
  85. Optical transient (GRB?) in Lynx
  86. GRB041211: Continued P60 Observations
  87. GRB041211, Faulkes Telescope optical observation
  88. GRB041211, BVRcIc field calibration
  89. GRB 041211: Infrared Observations
  90. GRB 041211: Optical follow-up in East Asian region
  91. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  92. GRB041015: Near-Infrared observations
  93. GRB 040924: Afterglow Color
  94. GRB 041006: GETS Optical Afterglow Observation
  95. Summary of the recent bursts from SGR 1806-20
  96. GRB 041006: Optical Observations
  97. GRB041006, late-time optical photometry
  98. GRB041006: RTT150 Optical Observations
  99. GRB041015 : Multi epoch optical observations
  100. GRB041006: RTT150 Optical Observations

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