NSRRC, Hsinchu
Taiwan Photon Source (TPS) is a low emittance third-generation light source which is currently under construction in the NSRRC site in Taiwan. TPS consists of 24 double-bend cells and its circumference is 518.4 m. A 496.8-m booster with multi-bend structure is designed. The alternative lattices, such as high/low betax, chicanes with double-vertical-waists in the long straights, and short bunches with low momentum compactions, etc., are investigated. Orbit and coupling corrections and stability issues are studied. Touschek lifetime and effects due to insertion devices are simulated. Works on impedance estimation and instability simulations are performed.
NSRRC, Hsinchu
Touschek scattering is an important beam lifetime limiting effect for the TPS storage ring due to several challenges such as low emittance, small physical aperture and large second-order momentum compaction factor (nonlinear longitudinal motion). The Touschek relevant energy acceptance is determined by these challenges, therefore a reliable estimate of the Touschek lifetime is essential. We obtained Touschek induced betatron oscillation amplitudes in three sections (LS, SS and ARC) and RF bucket acceptance analytically and with simulations. In this paper, we present the energy acceptance and Touschek lifetime calculations for the TPS storage ring in the cases for different chromaticity settings, ID chamber limitations, magnet multipole field errors and optics correction effects.
NSRRC, Hsinchu
To evaluate the feasibility for installing two insertion devices in the long straight sections (12 m long) of the TPS storage ring, two different kinds of the double mini-betay optics (symmetric and asymmetric configurations) were proposed to fulfill this purpose. In the symmetric case a quadrupole triplet is located at the center of the long straight, while in the asymmetric case a quadrupole doublet is used. The effects on the beam dynamics, such as the dynamic aperture, injection efficiency, and lifetime, etc., are presented.