Related papers: Impedance Analysis of Bunch Length Measurements at…
This report presents bunch length and energy spread measurements performed in April 2000 at the ATF Damping Ring, at KEK. Measurements were performed with the beam on and then off the linear (difference) coupling resonance. Due to strong…
In April 2000 the single bunch energy spread, bunch length, horizontal emittance, and vertical emittance were measured as functions of current in KEK's ATF damping ring. In this report the measurement results are analyzed in light of…
At the Accelerator Test Facility (ATF) at KEK intrabeam scattering (IBS) is a strong effect for an electron machine. It is an effect that couples all dimensions of the beam, and in April 2000, over a short period of time, all dimensions…
KEK-ATF is studying the low-emittance multi-bunch electron beam for the future linear collider. In ATF, thermionic gun is used to generate 20 bunches electron beam with the bunch spacing of 2.8 ns. Due to a distortion of the gun emission…
A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R&D effort. The upgrade consists of a…
We derive a simple relation for estimating the relative emittance growth in x and y due to intrabeam scattering (IBS) in electron storage rings. We show that IBS calculations for the ATF damping ring, when using the formalism of…
We construct a new detector to monitor $\gamma$ yields in bunch by bunch basis for the Laser Compton experiment at the KEK ATF which is capable to separate $\gamma$ rays in 5.6ns-spacing multi-bunch operation of the KEK ATF. In this article…
The longitudinal and transverse coupling impedances produced by the long slots in the Low Energy Ring of KEK B-factory are calculated. The power dissipated inside the vacuum chamber due to the fields scattered by the slots is evaluated…
With electron beam durations down to femtoseconds and sub-femtoseconds achievable in current state-of-the-art accelerators, longitudinal bunch length diagnostics with resolution at the attosecond level are required. In this paper, we…
ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback…
In the first part of the paper a generalized theoretical approach towards beam coupling impedances and stretched-wire measurements is introduced. Applied to a circular symmetric setup, this approach allows to estimate the systematic…
KEK-ATF is doing R&D establishing high-current and low-emittance electron beam for the future linear colliders. In ATF, 15 ps length electron beam is generated by combination of a thermionic gun, a couple of 357 MHz SHBs, and a S-band TW…
After a general introduction, the basic principles of wake-field and beamcoupling- impedance computations are explained. This includes time domain, frequency domain, and methods that do not include excitations by means of a particle beam.…
KEK-ATF is studying low emittance, multi-bunch electron beam for the future linear collider. The energy instability of the 1.5 GeV linac has been a problem making the beam injection to the damping ring unstable. Because the unstable beam…
In circular colliders, as well as in damping rings and synchrotron radiation light sources, beam halo is one of the critical issues limiting the performance as well as potentially causing component damage and activation. It is imperative to…
We have estimated contributions from the lossy and inductive vacuum chamber omponents to the broadband impedance of the NESTOR storage ring by using analytical formulas. As was expected considering the small ring circumference (15.44m), the…
In electron storage rings, it is possible to increase the bunch length by applying phase modulation to the radio frequency accelerating field by choosing appropriate parameters for the modulation. Such a bunch lengthening effect improves…
In this article we derive longitudinal impedance and wake function for an undulator setup with arbitrary undulator parameter, taking into account a finite transverse size of the electron bunch. Earlier studies considered a line…
Electron beams of linear induction accelerators experience deflective forces caused by RF fields building up as a result of accelerating cavities of finite size. These forces can significantly effect the beam when a long linac composed of…
The wire scanners are used for a measurement of the very small beam size and the emittance in Accelerator Test Facility (ATF). They are installed in the extraction beam line of ATF damping ring. The extracted beam emittance are ex=1.3x10-9…