Liu Zu-ping

The beam loss monitoring system for HLS storage ring

Abstract A beam loss monitoring system has been established at HLS. This paper gives its principle and scientific grounds. Study on the rings TBA structure and utilization of Monte-Carlo calculation to the shower electrons is important in its design. The system composition and performance are also introduced. The detector BLMs, data acquisition devices and host PC are linked via CAN bus. This system is helpful to analyze beam loss distribution and regulate the machine operation parameters.

Compensation of the influence of the 6 T wiggler on the 0.8 GeV storage ring in the national Synchrotron Radiation laboratory

Abstract A 6 T superconducting wiggler was installed in the Hefei 0.8 GeV storage ring. The influences of the wiggler on the storage ring are investigated. Using part of the existing quadrupoles we successfully compensated the tune shift and kept the optics distortion small enough. In most cases there was no significant change in the beam size. The dynamic apertures of the storage ring with the wiggler installed have been decreased to 50% of the original values when the wiggler was not installed, but they are still large enough. The calculation and experiment results are given in this article.

Conceptual design of Hefei Advanced Light Source (HALS) injection system

The Hefei Advanced Light Source(HALS) is a super low emittance storage ring and has a very short beam life time. In order to run the ring stablely, top-up injection will be necessary. The injection system will greatly affect the quality of beam. This article first gives a physics design of the injecting system. Then the injecting system is tracked under different errors. The responses of storage beam and injecting beam are given in the article.

Conceptual design of Hefei advanced light source

The conceptual of Hefei Advanced Light Source, which is an advanced VUV and Soft X-ray source, was developed at NSRL of USTC. According to the synchrotron radiation user requirements and the trends of SR source development, some accelerator-based schemes were considered and compared; furthermore storage ring with ultra low emittance was adopted as the baseline scheme of HALS. To achieve ultra low emittance, some focusing structures were studied and optimized in the lattice design. Compromising of emittance, on-momentum and off-momentum dynamic aperture and ring scale, five bend acromat (FBA) was employed. In the preliminary design of HALS, the emittance was reduced to sub nm ? rad, thus the radiation up to water window has full lateral coherence. The brilliance of undulator radiation covering several eVs to keVs range is higher than that of HLS by several orders. The HALS should be one of the most advanced synchrotron radiation light sources in the world.

The Commission of HEFEI Light Source After Reconstruction

Hefei light source was updated. Both the kicker system and RF system were reconstructed completely, and commissioned well. Two methods were used to suppresse transverse coupling instability. After the effect of SCW is compensated, beam life was increased. The global closed orbit is realized firstly in Hefei electron storage ring.

Ion-Induced Beam Instability in an Electron Storage Ring

In a small electron storage ring, such as the Hefei Light Source (HLS) ring, the newly generated ions, which can not escape from the beam potential and then are trapped from turn to turn, will lead to the beam instability. The ions created by the leading bunches can perturb the trailing bunches and also themselves during their subsequent passage, which will make the amplitude of beam oscillation be damped and anti-damped periodically. A computer simulation based on the strong-weak model shows a good agreement with our analytical model using the linear theory.