Differential cross sections for elastic scattering of electrons by CH4 in the energy range of 3 to 20 eV
Differential cross sections for elastic scattering of electrons by CH4 in the energy range of 3 to 20 eV
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CH4 在 3 至 20 eV 能量范围内对电子进行弹性散射的微分截面
DOI：
10.1088/0022-3700/15/18/024
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
M. Kubo
中科院分区：
文献类型：
--
作者：
Hiroshi Tanaka;T. Okada;L. Boesten;T. Suzuki;T. Yamamoto;M. Kubo
微分，积分和动量转移截面已被确定为电子的弹性散射CH 4。利用交叉电子束和分子束装置，采用相对流技术，测量了电子碰撞能量为3，5，6，7.5，9，10，15和20 eV时，散射角为30 - 140 °时，CH_4和He的弹性微分截面（DCS）之比。从该比率，绝对DCS通过利用已知的He的DCS来确定。由于纯转动激发不能分解，弹性DCS是室温下弹性和纯转动激发的总和。积分和动量传递截面由DCS计算。的CH 4 DCS的大小和角的行为相似的Ar在低于7.5 eV的冲击能量，也同意近似与密耦合计算的电子散射从多原子分子。在积分和动量转移截面中的宽最大值位于7.5 eV处。能量高达约7.5 eV的角分布是d波型共振的特征。
Differential, integral and momentum transfer cross sections have been determined for the elastic scattering of electrons by CH4. With the help of a crossed electron beam, molecular beam apparatus using the relative flow technique, the ratios of the elastic differential cross sections (DCS) of CH4 to those of He were measured at electron impact energies of 3, 5, 6, 7.5, 9, 10, 15, and 20 eV for scattering angles from 30 to 140 degrees . From the ratios, the absolute DCS were determined by utilising the known DCS of He. Because pure rotational excitation could not be resolved, the elastic DCS are the sum of elastic and pure rotational excitations at room temperature. Integral and momentum transfer cross sections were calculated from the DCS. The CH4 DCS are similar in size and in angular behaviour to those of Ar at impact energies below 7.5 eV, and also agree approximately with a close-coupling calculation for electron scattering from polyatomic molecules. A broad maximum in the integral and momentum transfer cross sections is located at 7.5 eV. The angular distributions at energies up to about 7.5 eV are characteristic of a d-wave type of resonance.