Multi-Bunch Stability Analysis of the Advanced Photon Source Upgrade Including the Higher-Harmonic Cavity

Title: Multi-Bunch Stability Analysis of the Advanced Photon Source Upgrade Including the Higher-Harmonic Cavity

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Abstract

Multi-bunch stability simulations were done for the very-low-emittance hybrid seven-bend-achromat (H7BA) lattice proposed for the Advanced Photon Source (APS) upgrade. The simulations, performed using tracking code elegant, were meant to determine whether the long-term wakefields of the higher-order modes (HOMs) of the main 352-MHz cavities will produce an instability. The multi-particle simulations include the important effects of the Higher-Harmonic Cavity (HHC) and the longitudinal impedance of the new vacuum chamber. These realistic simulations show that the HHC provides additional damping in the form of the Landau damping. Still, the HOMs may likely produce a multi-bunch instability which can be cured with more effective HOM damping or a longitudinal feedback system.

Authors:: Emery, L.; Borland, M.; Berenc, T.; Lindberg, R.

Publication Date:: 2015-01-01

Research Org.:: Argonne National Lab. (ANL), Argonne, IL (United States)

Sponsoring Org.:: USDOE Office of Science - Office of Basic Energy Sciences - Scientific User Facilities Division

OSTI Identifier:: 1351276

DOE Contract Number:: AC02-06CH11357

Resource Type:: Conference

Resource Relation:: Conference: 6th International Particle Accelerator Conference (IPAC 2015), 05/03/15 - 05/08/15, Richmond, VA

Country of Publication:: United States

Language:: English

Citation Formats


                    Emery, L., Borland, M., Berenc, T., and Lindberg, R. Multi-Bunch Stability Analysis of the Advanced Photon Source Upgrade Including the Higher-Harmonic Cavity.  United States: N. p., 2015. 
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                    Emery, L., Borland, M., Berenc, T., & Lindberg, R. Multi-Bunch Stability Analysis of the Advanced Photon Source Upgrade Including the Higher-Harmonic Cavity.  United States.

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                    Emery, L., Borland, M., Berenc, T., and Lindberg, R. Thu .  
        "Multi-Bunch Stability Analysis of the Advanced Photon Source Upgrade Including the Higher-Harmonic Cavity".  United States.

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@article{osti_1351276,

  title        = {Multi-Bunch Stability Analysis of the Advanced Photon Source Upgrade Including the Higher-Harmonic Cavity},

  author       = {Emery, L. and Borland, M. and Berenc, T. and Lindberg, R.},

  abstractNote = {Multi-bunch stability simulations were done for the very-low-emittance hybrid seven-bend-achromat (H7BA) lattice proposed for the Advanced Photon Source (APS) upgrade. The simulations, performed using tracking code elegant, were meant to determine whether the long-term wakefields of the higher-order modes (HOMs) of the main 352-MHz cavities will produce an instability. The multi-particle simulations include the important effects of the Higher-Harmonic Cavity (HHC) and the longitudinal impedance of the new vacuum chamber. These realistic simulations show that the HHC provides additional damping in the form of the Landau damping. Still, the HOMs may likely produce a multi-bunch instability which can be cured with more effective HOM damping or a longitudinal feedback system.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/1351276},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2015},

  month        = {1}

}

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