钠分子同位素替代对低温下的He-Na2冷碰撞体系转动激发积分散射截面的影响

用多体刚性椭球模型计算了不同能量下氦的同位素原子⁴He,¹⁰He与钠的同位素分子¹⁸Na₂,²³Na₂,³⁷Na₂ 替代碰撞体系的转动激发积分散射截面.通过分析⁴He,¹⁰He-¹⁸Na₂,²³Na₂,³⁷Na₂各转动激发积分散射截面的差异,总结出在钠分子的对称同位素替代情形下⁴He,¹⁰He -¹⁸Na₂,²³Na₂,³⁷Na₂碰撞体系转动激发积分散射截面随钠分子转动量子数和体系约化质量变化的规律.结果表明,体系的约化质量及入射原子相对碰撞能量的变化均给体系的碰撞截面带来不同程度的影响.另外,计算了相对入射能量为100 meV时,相互作用势的不同区域对¹⁰He-¹⁸Na₂,²³Na₂,³⁷Na₂各碰撞体系转动激发积分散射截面的贡献情况. 关键词： 多体刚性椭球模型 转动激发积分散射截面 钠同位素分子 椭球等势面

Influence of isotope substitution of sodium molecule on the integral cross sections of rotational excitation in low-temperature collisions of He-Na2

Multiple ellipsoid model is applied to the ⁴He,¹⁰He-¹⁸Na₂,²³Na₂, and ³⁷Na₂collision systems, and integral cross-sections for rotational excitation and the total collision cross-sections at the incident energy of 50,100 and 200 meV are calculated. By analyzing the differences of these integral cross-sections, the change rules of the integral cross sections with the increase of rotational angular quantum number of Na₂ molecule, as well as with the change of the reduced mass of symmetric isotopic substituted system are obtained. Based on the calculation, influence on the cross-sections exerted by the variations in the reduced mass of systems and in the relative incoming energy of incident atom is discussed. Moreover, at the relative incident energy of 100 meV, the contributions of different regions of the potential to integral cross-sections of rotational excitation for¹⁰He-¹⁸Na₂,²³Na₂ and ³⁷Na₂ collision systems are investigated.