Title :
The LHC beam pipe waveguide mode reflectometer
Author :
Kroyer, T. ; Borowiec, P. ; Caspers, F. ; Sulek, Z. ; Williams, L.R.
Author_Institution :
CERN, Geneva
Abstract :
The waveguide-mode reflectometer for obstacle detection in the LHC beam pipe has been intensively used for more than 18 months. The "Assembly" version is based on the synthetic pulse method using a modern vector network analyzer. It has mode selective excitation couplers for the first TE and TM mode and uses a specially developed waveguide mode dispersion compensation algorithm with external software. In addition there is a similar "In Situ" version of the reflectometer which uses permanently installed microwave couplers at the end of each of the nearly 3 km long LHC arcs. During installation a considerable number of unexpected objects have been found in the beam pipes and subsequently removed. Operational statistics and lessons learned are presented and the overall performance is discussed.
Keywords :
accelerator magnets; beam handling techniques; ion accelerators; proton accelerators; reflectometers; storage rings; synchrotrons; waveguides; Assembly version; LHC beam pipe; TE mode; TM mode; dispersion compensation algorithm; excitation couplers; external software; in situ version; magnet installation; microwave couplers; modern vector network analyzer; obstacle detection; operational statistics; synthetic pulse method; waveguide mode reflectometer; Assembly; Couplers; Inspection; Large Hadron Collider; Magnets; Particle beams; Quality assurance; Reflectometry; Signal analysis; Waveguide discontinuities;
Conference_Titel :
Particle Accelerator Conference, 2007. PAC. IEEE
Conference_Location :
Albuquerque, NM
Print_ISBN :
978-1-4244-0916-7
DOI :
10.1109/PAC.2007.4440830
