Simulation of effects of incident beam condition in p-p elastic scattering  

作　　者：于蕾 张高龙 I.Tanihata 乐小云 

机构地区：[1]School of Physics and Nuclear Energy Engineering, Beihang University [2]International Research Center for Nuclei and Particles in the Cosmos Beihang University [3]Key Laboratory of Micro-nano Measurement Manipulation and Physics (Ministry of Education),Beihang University [4]Research Center for Nuclear Physics, Osaka University

出　　处：《Chinese Physics C》2014年第2期5-9,共5页中国物理C（英文版）

基　　金：Supported by National Nature Science Foundation of China(11035007,11235002,11175011);Special Joint Project of Beijing Municipal Education Commission

摘　　要：The simulation is performed for the monitors of beam direction and beam position for p-p elastic scattering. We set several variables to simulate the monitors of incident beam condition changes： beam positions at the quadrupole magnet and target in beam line polarimeter（BLP2）, distance between quadrupole magnet and target,size of plastic scintillators, distance between the target in BLP2 and the centers of plastic scintillators, and beam polarization. Through the rotation of the coordinate system, the distributions of scattered and recoiled protons in the laboratory system were obtained. By analyzing the count yields in plastic scintillators at di？erent beam positions,we found that the beam incident angular change（0.35°） could be detected when the asymmetry of geometries of left and right scintillators in BLP2 was changed by 6%. Therefore, the scattering angle measured in the experiment can be tracked by these monitors.The simulation is performed for the monitors of beam direction and beam position for p-p elastic scattering. We set several variables to simulate the monitors of incident beam condition changes： beam positions at the quadrupole magnet and target in beam line polarimeter（BLP2）, distance between quadrupole magnet and target,size of plastic scintillators, distance between the target in BLP2 and the centers of plastic scintillators, and beam polarization. Through the rotation of the coordinate system, the distributions of scattered and recoiled protons in the laboratory system were obtained. By analyzing the count yields in plastic scintillators at di？erent beam positions,we found that the beam incident angular change（0.35°） could be detected when the asymmetry of geometries of left and right scintillators in BLP2 was changed by 6%. Therefore, the scattering angle measured in the experiment can be tracked by these monitors.

关 键 词：p-p elastic scattering incident beam condition monitor Monte Carlo method 

分 类 号：O572.212[理学—粒子物理与原子核物理]