February 28 - March 2, 2000
| NLC Technical Page | SLAC Home Page |
- 1st Posting - Workshop on Broad Impedance Measurements & Modeling
- 2nd Posting - Second Circular
The production of short, stable bunches is key for linear collider injectors. The papers referenced here illustrate some recent work the topic:
SLC Damping Rings:
The SLAC Damping Ring vacuum chamber was almost entirely replaced in 1992-3 in order to raise the threshold of the microwave instability. The threshold was actually lowered by about 30%, but the amplitude of the instability was also reduced. This paper "High-Intensity Single Bunch Instability Behavior In The New SLC Damping Ring Vacuum Chamber", (SLAC Publication-6894) reports our observations. "Simulations of the Longitudinal Instability in the New SLC Damping Rings" (SLAC-Publication-6878) reports our attempts to explain the results. "Impedance Calculations for the Improved SLC Damping Rings"( SLAC-Publication-6254 ) outlines the design efforts during the chamber replacement project. Each component was modeled.
More recent observations are reported in:
- Sawtooth Instability Studies in the Stanford Linear Collider Damping Rings
- Signals from Microwave Unstable Beams in the SLC Damping Rings
Accelerator Test Facility (ATF) at KEK:
The ATF damping ring is intended to serve as a prototype linear collider low emittance source. Estimates of the impedance ( ESTIMATION OF THE LONGITUDINAL IMPEDANCE OF THE ATF DAMPING RING. By M. Takao, T. Higo (KEK, Tsukuba), K.L.F. Bane (SLAC). KEK-91-14, Mar 1992. 18pp. Published in Particle Accel.Conf: IEEE 1991:506-508 (QCD183:P3:1991)) did not indicate the observed bunch lengthening: "Impedance Measurement of ATF DR" is a paper that summarizes observations,
CESR data on single bunch lengthening is presented in "Streak Camera Measurements of the Longitudinal Distribution of a Single Bunch in CESR". They report good agreement with a simple broadbad resonator model.
Paper from PF-AR with some discrepancy between expected and observed instability threshold.
Paper from APS showing some sawtooth behaviour
Paper from NSLS showing turbulent bunch length oscillations
Impedance and instability estimates for DAFNE
- Impedance of DAFNE shielded bellows
- Collective Effects and Impedance Study for the Dafne PHI Factory.
RF Screening by Thin Resistive Layers
Paper showing a theoretical analysis of evolution of the sawtooth instability
Paper by Mosnier on the theory of sawtooth
This page created on 11/13/98
and updated on October 02, 2002 by Nixx.
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