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arXiv · 0906.3210

High-resolution inelastic X-ray scattering studies of the state-resolved differential cross-section of Compton excitations in helium atoms

B. P. Xie·L. F. Zhu·K. Yang·B. Zhou·N. Hiraoka·Y. Q. Cai·Y. Yao·C. Q. Wu·E. L. Wang·D. L. Feng
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Abstract

The state-resolved differential cross sections for both the 1s2 1S0 - 1s2s 1S0 monopolar transition and the 1s2 1S0 - 1s2p 1P1 dipolar transition of atomic helium have been measured over a large momentum transfer region by the high-resolution inelastic X-ray scattering (IXS) for the first time. The almost perfect match of the present measurement with the theoretical calculations gives a stringent test of the theoretical method and the calculated wavefunctions. Our results demonstrate that high-resolution IXS is a powerful tool for studying the excitations in atoms and molecules.

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B. P. Xie, L. F. Zhu, K. Yang, B. Zhou, N. Hiraoka, Y. Q. Cai, Y. Yao, C. Q. Wu, E. L. Wang, D. L. Feng. 2009-06-17. High-resolution inelastic X-ray scattering studies of the state-resolved differential cross-section of Compton excitations in helium atoms. https://doi.org/10.1103/physreva.82.032501

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