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BiBTeX citation export for WEPP27: An Alternative Processing Algorithm for the Tune Measurement System in the LHC

@InProceedings{grech:ibic2020-wepp27,
  author       = {L. Grech and D. Alves and M. Gąsior and S. Jackson and O.R. Jones and T.E. Levens and G. Valentino and J. Wenninger},
% author       = {L. Grech and D. Alves and M. Gąsior and S. Jackson and O.R. Jones and T.E. Levens and others},
% author       = {L. Grech and others},
  title        = {{An Alternative Processing Algorithm for the Tune Measurement System in the LHC}},
  booktitle    = {Proc. IBIC'20},
  pages        = {162--165},
  paper        = {WEPP27},
  language     = {english},
  keywords     = {simulation, controls, betatron, damping, feedback},
  venue        = {Santos, Brazil},
  series       = {International Beam Instrumentation Conference},
  number       = {9},
  publisher    = {JACoW Publishing, Geneva, Switzerland},
  month        = {10},
  year         = {2020},
  issn         = {2673-5350},
  isbn         = {978-3-95450-222-6},
  doi          = {10.18429/JACoW-IBIC2020-WEPP27},
  url          = {https://www.jacow.org/ibic2020/papers/wepp27.pdf},
  note         = {https://doi.org/10.18429/JACoW-IBIC2020-WEPP27},
  abstract     = {The betatron tune in the Large Hadron Collider (LHC) is measured using a Base-Band-Tune (BBQ) system. Processing of these BBQ signals is often perturbed by 50Hz noise harmonics present in the beam. This causes the tune measurement algorithm, currently based on peak detection, to provide incorrect tune estimates during the acceleration cycle with values that clearly oscillate between neighbouring harmonics. The LHC tune feedback cannot be used to its full extent in these conditions as it relies on stable and reliable tune estimates. In this work we present two alternative tune measurement algorithms, designed to mitigate this problem by ignoring small frequency bands around the 50Hz harmonics and estimating the tune from spectra with gaps. One is based on Gaussian Processes and the other is based on a weighted moving average. We compare the tune estimates of the new and present algorithms and put forward a proposal that can be implemented during the renovation of the BBQ system for the next physics run of the LHC.},
}