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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"

21812 results found.

  1. GRB050128,optical observations
  2. GRB 050126: A NIR afterglow candidate in the revised XRT error circle
  3. GRB 050126: Radio Observations
  4. GRB050128 Swift-BAT observations
  5. GRB 050128: Swift XRT prompt afterglow position
  6. HETE #3667: P60 Observations
  7. GRB 050124: K-band afterglow observations
  8. GRB050126: MASTER optical observations
  9. GRB 050126: Prompt XRT detection and localization
  10. GRB050124: No Swift UVOT Detection of Afterglow Emission
  11. GRB 050124, SMARTS optical/IR observations
  12. GRB 050117a: Radio Observations
  13. GRB 050124: NIR Candidates from Keck/NIRC
  14. GRB 050124 : Lulin R-band follow-up observation
  15. GRB050124: Updated Swift XRT Position and Fluxes
  16. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  17. GRB 050123 : I-band follow-up observation
  18. GRB 050123: KAIT observations
  19. GRB050123: P60 Observations
  20. CFHTLS optical transient unlikely to be a GRB
  21. GRB050117a: Radio Observations
  22. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  23. GRB050117: Palomar WIRC Ks-band observations
  24. GRB 050117, I-band observations
  25. GRB050117: Refined XRT position
  26. GRB050117: MASTER optical observations
  27. MASTER:GRB050117 SWIFT
  28. SGR 1806-20: Further VLA Observations
  29. SGR 1806-20: Further low frequency GMRT results
  30. SGR 1806-20: Further VLA Observations
  31. SGR1806-20: Swift-BAT observations of two additional bursts
  32. Further VLA observations of SGR 1806-20
  33. Further ATCA observations of SGR 1806-20
  34. Fourth Epoch VLA observations of SGR 1806-20
  35. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  36. ATCA observations of SGR 1806-20
  37. SGR 1806-20, RHESSI observations of the 041227 giant flare
  38. Third epoch observations of SGR 1806-20 with VLA
  39. Second Epoch VLA observations of SGR 1806-20
  40. Second-epoch VLA observations of SGR 1806-20
  41. SGR1806: Detection of a Sudden Ionospheric Disturbance
  42. VLA observations of SGR 1806-20
  43. SGR1806 VLA Observations
  44. VLA observations of SGR 1806-20
  45. GRB 041217: Optical observations
  46. GRB041219, early time observations
  47. The giant outburst from SGR 1806-20
  48. GRB041228: ROTSE-III Optical Observations
  49. GRB041219; RXTE ASM Observations
  50. NIR Observations of GRB 041219
  51. GRB041226: ROTSE-III Optical Observations
  52. GRB041223: decay of the afterglow
  53. GRB041224: ROTSE-III Optical Observations
  54. GRB 041224: near-infrared observations with REM
  55. GRB041223: optical and NIR observations with REM
  56. Swift-BAT Time History of GRB041219
  57. GRB 041219: TAROT optical observations
  58. GRB 041218: TAROT optical observations
  59. GRB 041223: J-band observations of the afterglow
  60. GRB 041223: Detection of Optical Transient with LCO40
  61. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  62. GRB 041219c: PROMPT Observations
  63. GRB041223: ROTSE-III Optical Observations
  64. GRB 041218: optical observations
  65. GRB 041219: Second Epoch WSRT Radio Observations
  66. GRB 041219: WSRT Radio Afterglow Detection
  67. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  68. GRB 041218: Optical observations
  69. GRB 041219 : optical follow-up observations
  70. Deep RAPTOR observations during GRB 041219
  71. GRB 041218 Optical Observations
  72. GRB 041219 Optical Observations
  73. GRB041219: Optical Afterglow Detection
  74. GRB041219: Continued NIR Observations
  75. GRB 041219: Radio Afterglow Detection
  76. GRB 041218 : Radio Observations
  77. GRB 041218: R-band optical observations
  78. GRB041218: Liverpool Telescope optical observations
  79. GRB041218: optical observations
  80. GRB041218: Continued P60 Optical Observations
  81. GRB 041219: Infrared Afterglow Candidate
  82. GRB 041219: Infrared Afterglow Candidate
  83. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  84. GRB041219: P60 Optical Observations
  85. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  86. GRB 041217: PROMPT Observations
  87. GRB041218: optical observations
  88. GRB 041218; optical candidate
  89. GRB 041218: Optical observations
  90. GRB 041217: LCO40 Optical Observations and Possible Candidates
  91. GRB041217: Optical Observations
  92. GRB041217: NIR and optical observations with REM
  93. GRB041217: P60 Optical Observations
  94. GRB041217: Infrared Observations
  95. GRB041211: Faulkes Telescope continued optical monitoring
  96. Optical transient (GRB?) in Lynx
  97. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  98. GRB041211: Continued P60 Observations
  99. GRB041211: RAPTOR observations
  100. GRB041211, Faulkes Telescope optical observation

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