USTC/NSRL, Hefei, Anhui
Funding: Work supported by National Natural Science Foundation of China (No.10175062 & 10575100).
In recent years, Fixed Field Alternating Gradient (FFAG) accelerator is becoming a highlight in particle accelerator R&D area. This type of accelerator could accelerate ions with higher beam current than conventional strong focusing circular accelerator, which could be more useful for the study of radioactive material. In this paper, conceptual design of an FFAG with high Helium ion beam current and a few MeV energy which is dedicated to study the impact of Helium embitterment to fusion reactor envelope material is discussed, the periodic focusing structure model is given, following which the calculation result of magnetic field is also presented.
USTC/NSRL, Hefei, Anhui
Funding: Work supported by National Natural Science Foundation of China (No.10175062 & 10575100).
The light pulse interval adjustment at Hefei Light Source (HLS) can be realized by using pulsed orbit bump technique, which requires for high-frequency repetitive, high magnetic flux density, short pulse kicker magnet system of which the power supply modulator should be specially designed. The technique of solid state modulator based on MOSFET is being developed in National synchrotron Radiation Laboratory (NSRL). In this paper, the design of a prototype of solid-state modulator with 20 MOSFETs in parallel is introduced, including triggering system, drive circuit, transformer configuration. The oscillation induced by parasitic capacitance and inductance is discussed. This prototype with four stage adder can achieve 100ns width power pulse output with 112A, 2.4 kV to the kicker.
USTC/NSRL, Hefei, Anhui
FEL/Duke University, Durham, North Carolina
Funding: Work supported by US Air Force Office of Scientific Research medical FEL grant FA9550-04-01-0086 (YKWu), also supported by National Natural Science Foundation of China (No.10175062 and 10575100).
Many modern light source storage rings use a basic magnetic lattice structure consisting of a number of repetitive periodic lattice block, the super periods. The study of one super-period can reveal the dynamical proprieties of the storage ring. Unlike the traditional approach of studying the one-turn map of the storage ring, the work focuses on the study of a super-period lattice, which allows us to gain new insight into the storage ring dynamics using a simpler magnetic structure. In this paper, both analytical and numerical techniques, including Lie Algebra and Normal Form, and particle tracking and frequency analysis, are used to study the nonlinear dynamics of one super-period of a standard double-bend achromat (DBA) and triple-bend achromat (TBA) with two or more nonlinear elements (e.g. sextupoles). The relationship between the super-period dynamics and storage ring dynamics is explored in terms of the global lattice tuning and local lattice selection for straight sections.
H. Hao is currently working as a visiting scholar at Duke University Free Electron Laser Laboratory.
