JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF
AU - Lagniel, J.-M.
ED - Zimmermann, Frank
ED - Tanaka, Hitoshi
ED - Sudmuang, Porntip
ED - Klysubun, Prapong
ED - Sunwong, Prapaiwan
ED - Chanwattana, Thakonwat
ED - Petit-Jean-Genaz, Christine
ED - Schaa, Volker R.W.
TI - Excitation of the σ_{l}_{l} = 90° Resonance by the Cavity RF Accelerating Fields
J2 - Proc. of IPAC2022, Bangkok, Thailand, 12-17 June 2022
CY - Bangkok, Thailand
T2 - International Particle Accelerator Conference
T3 - 13
LA - english
AB - In RF linacs the longitudinal focusing is done by nonlinear forces and at high accelerating fields the zero-current longitudinal phase advance per longitudinal focusing period σ₀l_{l} can be high. The nonlinear components of the RF field (sextupolar, octupolar and higher order components) can then excite parametric resonances, including the 4th-order resonance (σ_{l}_{l} = 90°) when σ₀l_{l} is higher than 90°, inducing strong longitudinal emittance growths and acceptance reductions. The longitudinal beam dynamics is therefore complex, even when the nonlinear space-charge forces are ignored. The parametric resonance excitation by the RF field is analyzed before discussing the additional effect of the nonlinear space-charge forces, in particular to explain why the zero-current longitudinal phase advance per transverse focusing period σ₀l_{t} is not a relevant parameter. Examples are given in the SPIRAL2 linac case.
PB - JACoW Publishing
CP - Geneva, Switzerland
SP - 152
EP - 155
KW - resonance
KW - focusing
KW - space-charge
KW - linac
KW - cavity
DA - 2022/07
PY - 2022
SN - 2673-5490
SN - 978-3-95450-227-1
DO - doi:10.18429/JACoW-IPAC2022-MOPOST038
UR - https://jacow.org/ipac2022/papers/mopost038.pdf
ER -