Zhang, Zhang Shancai.
(Shancai Zhang)

MOPOS42 Parameter Analysis For A High-Gain Harmonic Generation FEL By Numerical Calculation Based On 1D Theory
Yuhui Li, Qika Jia, Shancai Zhang (USTC/NSRL, Hefei, Anhui)

The high-gain harmonic generation (HGHG) free-electron laser (FEL) is an important candidate for a fourth-generation light source. Lots of theoretical work has been performed. Recently a further 1D theory about HGHG FEL has been developed. It considers the effects of different parameters for the whole process. An initial program based on this theory has been made. In this paper, a brief comparison of the results from this 1D program and from TDA (3D code) is discussed. It also analyses the parameters for Shanghai deep ultra violate free-electron laser source (SDUV-FEL), including electron beam energy spread, seed laser power, strength of dispersion section etc.

TUPOS36 Simplified Method for Experimental Spectral Ratio Calculation of CHG-FEL
Nian Chen, Duohui He, Ge Li, Yuhui Li, Pengfei Zhang, Shancai Zhang (USTC/NSRL, Hefei, Anhui)

The goal of the coherent harmonic generation free-electron laser (CHG-FEL) experiment in NSRL is to gain a 266nm coherent radiation and a large spectral ratio which is defined as the ratio of coherent intensity to incoherent intensity in infinitesimal bandwidth and solid angle aperture. The intensity measurements are made through a spectrometer whose spectral and angular aperture is much larger than the actual apertures of coherent radiation and smaller than those of incoherent radiation. So the measured ratio is integral ratio integrated over the actual apertures of the measurement system. This paper is mainly on giving a formula and designing a computer program to calculate the spectral ratio according to the bandwidth and solid angle aperture of the measurement system, taking into account the measured magnetic field of optical klystron and the energy spread of the electron beam. The code will soon be employed in our next turn experiment.

TUPOS38 Design of Undulator for the Shanghai DUV-FEL
Qika Jia, Duohui He, Shengkuan Lu, Shancai Zhang (USTC/NSRL, Hefei, Anhui), Yun Cao, Zhimin Dai, Zhentang Zhao, Qiaogen Zhou (SINAP, Jiading, Shanghai)

The design study of the undu1ator for Shanghai deep ultra violate free electron laser source (SDUV-FEL) is presented. The optimum undulator parameters for the FEL performance have been studied. The scheme of focusing and segmentation is discussed. The requirements of undulator magnet field and main technical demand are given.