Longitudinal wakefield for an axisymmetric collimator

Journal Article · Fri May 25 04:00:00 EDT 2012 · Physical Review Special Topics. Accelerators and Beams

DOI:https://doi.org/10.1103/PhysRevSTAB.15.054405· OSTI ID:1049286

Blednykh, A; Krinsky, S

We consider the longitudinal point-charge wakefield, w(s), for an axisymmetric collimator having inner radius b, outer radius d, inner length g, and taper length L. The taper angle {alpha} is defined by tan {alpha} = (d-b)/L. Using the electromagnetic simulation code ECHO, we explore the dependence of the wakefield on a collimator's geometric parameters over a wide range of profiles: from small-angle tapers to step-function transitions. The point-charge wakefield is determined using an approximation introduced by Podobedov and Stupakov. We have found it useful to exhibit the wakefield as a function of the scaled variable s/d{alpha}. For small taper angles, our results illustrate the satisfaction of the longitudinal scaling found by Stupakov, Bane, and Zagorodnov; and for larger taper angles, the breaking of this longitudinal scaling is clearly depicted. The use of the scaled variable s/d{alpha} turns out to be especially well suited to describing the wakefield for a collimator with step-function profile ({alpha} = {pi}/2).

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: USDOE SC OFFICE OF SCIENCE (SC)
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1049286
• Report Number(s): BNL--98272-2012-JA; 39KC02000
• Journal Information: Physical Review Special Topics. Accelerators and Beams, Journal Name: Physical Review Special Topics. Accelerators and Beams Journal Issue: 5 Vol. 15; ISSN 1098-4402
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
APPROXIMATIONS
COLLIMATORS
POINT CHARGE
SIMULATION
angles
axisymmetric
collimator
national synchrotron light source
wakefield