The Short-Range Resistive Wall Wakefields

Journal Article · Mon Apr 01 04:00:00 EST 1996 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.50300· OSTI ID:288706

Bane, K L; Sands, M ^[1]

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1. Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States)

In an accelerator when the bunch length becomes comparable to a characteristic distance {ital s}{sub 0}, one which depends on the radius and the conductivity of the beam tube and in typical structures is on the order of tens of microns, the usual formulas for the resistive wall wakefield do not apply. In this report we derive the short-range resistive wall wakefields of an ultra-relativistic point particle in a metallic, cylindrical tube, both for a model in which the wall conductivity is taken to be independent of frequency and for one in which a frequency dependence is included. On this scale the wakefield is found to be dominated by a damped, high frequency resonator component. For the case of constant conductivity the resonant frequency is given by {omega}={radical}(3){ital c}/{ital s}{sub 0} and the {ital Q}-factor equals {radical}(3)/2. We provide a physical model to explain these results. For the case of a frequency dependent conductivity the resonator parameters depend also on the relaxation time of the metal {tau}. For {ital c}{tau}/{ital s}{sub 0}{approx_gt}0.5 the frequency {omega}{approximately}{radical}2{omega}{sub {ital pc}}/{ital b}, with {omega}{sub {ital p}} the plasma frequency of the free electrons in the metal and {ital b} the tube radius, and the 1/{ital e} damping time becomes 4{tau}. Finally, we calculate the wakefield and loss factor of a short Gaussian bunch. {copyright} {ital 1996 American Institute of Physics.}

• OSTI ID: 288706
• Report Number(s): CONF-9509227--
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 367; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATORS
BEAM BUNCHING
BEAM OPTICS
ELECTRIC CONDUCTIVITY
ELECTRON BEAMS
OSCILLATION MODES
WAKES
WALL EFFECTS