Calibration of beam position detector channel of heavy ion accelerator based on automatic gain method

Aiming at the requirement of beam position measurement accuracy for heavy ion accelerator, the automatic gain calibration method of beam position detector channel is studied, and the design of automatic gain calibration of simulated BPM signal, laboratory calibrated BPM signal, and online beam BPM signal is realized. Firstly, the overall design of the ADC automatic gain system is introduced. Secondly, each sub-function module of the ADC automatic gain system is designed and implemented on Matlab software, and the correction processing with noise and without noise is compared. Finally, the consistency of simulated beam data, laboratory calibration data, and online beam data is tested respectively. The experimental results show that the method makes the four noisy analog signals basically the same in amplitude, and effectively reduces the error caused by the inconsistent gain of each signal channel of the ADC.

I. Introduction

The Heavy Lon Research Facility in Lanzhou (HIRFL), also known as the Heavy Ion Research Facility in Lanzhou, is the largest heavy ion research facility with the largest number of accelerated ions and the highest energy in China. The main technical indicators have reached the international advanced level [1]. HIRFL is composed of an ECR (electron cyclotron resonance) ion source, fan focusing cyclotron, separation fan cyclotron, radioactive beam line, new cooling storage ring main ring, and experimental ring [2]. HIRFL can accelerate all ions and can provide a variety of stable nuclear beams and radioactive beams with a wide energy range and high quality to carry out heavy ion physics and interdisciplinary research [3].