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arXiv · 2002.02047

Measurability of Coulomb wavepacket scattering effects

Scott E. Hoffmann
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Abstract

A previous paper [J. Phys. B: At. Mol. Opt. Phys. 50, 215302 (2017)] showed that partial wave analysis becomes applicable to nonrelativistic Coulomb scattering if wavepackets are used. The scattering geometry considered was special: that of a head-on collision between the wavepacket and the centre of the potential. Our results predicted, in this case, a shadow zone of low probability for small angles around the forward direction for the description of alpha scattering from a gold foil. In this paper we generalize the results to the case of a nonzero impact parameter, a displacement of the wavepacket centre perpendicular to the average momentum direction. We predict a large flux in the forward direction from events with large impact parameters. We find a significant probability of scattering into the deviation region for impact parameters of order the spatial width of the wavepacket. Averaging over impact parameters produces predictions in excellent agreement with the Rutherford formula down to lower angles than for the zero impact parameter prediction. We consider issues that would arise in a real experiment and discuss the possibility of measuring a deviation from the Rutherford formula.

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Scott E. Hoffmann. 2020-02-06. Measurability of Coulomb wavepacket scattering effects. https://arxiv.org/abs/2002.02047

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