The short-range resistive wall wakefields

Conference · Fri Dec 01 04:00:00 EST 1995

OSTI ID:179281

Bane, K L.F.; Sands, M

In an accelerator when the bunch length becomes comparable to a characteristic distance 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 the authors 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 c/s{sub 0}) and the Q-factor equals {radical}(3/2). They 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 c{tau}/s{sub 0} {approx_gt} 0.5 the frequency {omega} {approx} {radical}(2{omega}{sub p}c/b), with {omega}{sub p} the plasma frequency of the free electrons in the metal and b the tube radius, and the 1/e damping time becomes 4{tau}. Finally, they calculate the wakefield and loss factor of a short Gaussian bunch.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 179281
• Report Number(s): SLAC-PUB--95-7074; CONF-9509227--10; ON: DE96004688
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATORS
ANALYTICAL SOLUTION
BEAM BUNCHING
BEAM DYNAMICS
CAVITY RESONATORS
ELECTRIC CONDUCTIVITY
ELECTROMAGNETIC FIELDS