Author: Ma, T.J.
Paper Title Page
MOPME041 Design and Calculation of the Stripline Beam Position Monitor for HLS II Storage Ring 562
 
  • F.F. Wu, C. Cheng, W.B. Li, P. Lu, T.J. Ma, B.G. Sun, H. Xu, Y.L. Yang, Z.R. Zhou
    USTC/NSRL, Hefei, Anhui, People's Republic of China
 
  Funding: Supported by the National Science Foundation of China (10875117, 11005105, 11175173)
According to the requirements of HLS II upgraded, in order to acquire the non-intercepting measurement of beam position and quadrupole component, a new stripline beam position monitor (BPM) was designed for storage ring. The BPM parameters were optimized to acquire impedence matching with characteristic impedance of the external transmission lines and the coupling coefficients between the electrodes were calculated. According to the difference/sum and log-ratio methods, the horizontal and vertical sensitivities, mapping figures and fitting polynomials wered acquired. The results showed that sensitivities using log-ratio method were bigger than those using difference/sum method. The sum signal was also simulated when beam displacement varied from (0 mm, 0 mm) to (5 mm, 5 mm), the result showed that the variation of normalized sum signal was no more than ±6%. The gaussian weighted method of a two-dimensional grid structure was used to simulate the gaussian bunch and simulate the beam transverse quadrupole component changing with position (x, y), the result showed that the beam transverse quadrupole component changed linearly with position combination (x2-y2).
 
 
MOPME042 A PRELIMINARY SIMULATION OF BPM SIGNAL DIODE DETECTOR FOR HLS II TUNE MEASUREMENT SYSTEM* 565
 
  • J.J. Zheng, P. Lu, T.J. Ma, B.G. Sun, Y.L. Yang, J.Y. Zou
    USTC/NSRL, Hefei, Anhui, People's Republic of China
 
  Funding: Supported by National Natural Science Foundation of China (11105141, 11175173) and the Fundamental Research Funds for the Central Universities (WK2310000015)
A high sensitivity BPM signal detection front-end electronics has been designed for HLS II tune measurement system according to the HLS II upgrade requirements. Classical tune measurement systems filter out just one or a few of these betatron sidebands frequency. As a consequence, most of the betatron energy is dropped and only a very small energy remains for further processing. A new method, referred to as Direct Diode Detection (3D) by LHC[1], improves the situation. In this paper, the HLS II BPM signals have been calculated out in time domain and frequency domain. Basing on the characteristics of HLS II BPM signal, a preliminary simulation is performed to test and verify the feasibility of diode detector for HLS II tune measurement system. The simulation results clearly show that the technique of diode-based circuit can be applied to HLS II tune measurement.
 
 
MOPME043 Calibration of Beam Position Monitors in the Injector of HLS II 568
 
  • J.Y. Zou, J. Fang, W.B. Li, P. Lu, T.J. Ma, B.G. Sun, Y.L. Yang, Z.R. Zhou
    USTC/NSRL, Hefei, Anhui, People's Republic of China
 
  Funding: Supported by the National Science Foundation of China (11175173, 11105141)
A beam position monitor(BPM) system is being installed to improve the beam position measurement of the injector at the upgrade project of Hefei Light Source (HLS II). The new BPM system is consists of 19 stripline BPMs and 19 Libera Brilliance Single Pass modules. Before installation, the response of the BPMs must be mapped to improve the accuracy of measurement. The theoretical equations of both position and quadrupole component of the BPM are calculated first, using both formula and matlab simulation. A laboratory calibration system is built. The inconsistency of Libera Brilliance Single Pass channels is measured to improve the accuracy of calibration. The calibrating results show the position sensitivity is less than 5% difference compare to the theoretical value, while the quadrupole component sensitivity is less than 10% difference.