An investigation of the anomalous asymptotic behavior of elastic electron scattering of helium
| Autor: | N. Hiraoka, Ke Yang, Kuan-Li Yu, Ku-Ding Tsuei, Ya-Wei Liu, Tao Xiong, Xin-Chao Huang, Lin-Fan Zhu |
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| Rok vydání: | 2020 |
| Předmět: |
Physics
010304 chemical physics Scattering Momentum transfer Atoms in molecules General Physics and Astronomy chemistry.chemical_element Electronic structure Electron 010402 general chemistry 01 natural sciences 0104 chemical sciences chemistry 0103 physical sciences Atomic nucleus Physical and Theoretical Chemistry Born approximation Atomic physics Helium |
| Zdroj: | The Journal of Chemical Physics. 152:034304 |
| ISSN: | 1089-7690 0021-9606 |
| DOI: | 10.1063/1.5128947 |
| Popis: | For the inelastic electron scattering of atoms and molecules, a consensus has been reached that the first Born approximation is easily approached by decreasing the momentum transfer at the same impact electron energy or increasing the impact electron energy at the same momentum transfer. Although this consensus is applicable for the elastic electron scattering of most atoms and molecules, it is violated for helium where the experimental differential cross sections deviate from the first Born approximation prediction gradually with the decrease of squared momentum transfer at the same impact electron energy. Since this anomalous phenomenon was observed more than 40 years ago, the intrinsic mechanism is not explicit. In the present work, using the high-resolution x-ray scattering, we isolate the scattering contribution from the nucleus and directly obtain the pure electronic structure of helium. Then, the anomalous asymptotic behavior of the elastic electron scattering of helium has been elucidated, i.e., in the small squared momentum transfer region, the scattering contribution from the target's electrons is counteracted by the one from the atomic nucleus, which results in the residual contribution beyond the first Born approximation being drastically enlarged. |
| Databáze: | OpenAIRE |
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