低能正电子对氦原子弹性散射中极化势研究

RESEARCH FOR THE POLARIZATION POTENTIALS USED FOR THE ELASTIC SCATTERING OF LOW-ENERGY POSITRON BY HELIUM ATOM

本文研究了低能正电子对氦原子弹性散射中半经验极化势对散射截面的影响。结果表明,所计算的截面的精确性取决于极化势的短程特性。在含有截止函数的势中,增大可调参量将使截面的计算值在入射正电子能量大于某一数值时减小,小于该值时增大。如欲精确描述实验规律,首先要选取恰当的极化势。

In this paper, The effect of the semi-empirical polarization potentials used for the elastic scattering of low-energy positrpn by Helium atom on the scattering cross-section is studied. From the results it is shown that the accuracy of the calculated scattering cross-sections depend on the short-range behavior of the polarization potentials. In a potential including a cutoff function, increasing the numerical values of the adjustable parameter will make the calculated values of cross-section legetting to decrease while the energy of incident positron is greater than a definite value, and to increase while less than the value. So that if we hope to formulate the experimental results accurately, the first thing js to select a suitable polarization potential,