Differential cross sections for single ionization of Li in collisions with fast protons and O$^{8+}$ ions

TL;DR

This paper calculates and compares differential cross sections for single ionization of lithium by fast protons and O$^{8+}$ ions, using advanced models, and finds good agreement with recent experimental data, highlighting the importance of including heavy particle interactions.

Contribution

It introduces detailed calculations of fully and doubly differential cross sections for lithium ionization, emphasizing the role of heavy particle interactions and polarization effects in matching experimental results.

Findings

Reproduces the satellite peak structure in FDCS for Li(2s).

Highlights the importance of heavy particle (NN) interaction.

Shows polarization effects are crucial for accurate modeling.

Abstract

We study the process of single ionization of Li in collisions with H$^+$ and O$^{8+}$ projectile ions at 6 MeV and 1.5-MeV/amu impact energies, respectively. Using the frameworks of the independent-electron model and the impact parameter picture, fully (FDCS) and doubly (DDCS) differential cross sections are evaluated in the continuum distorted-wave with eikonal initial-state approximation. Comparisons are made with the recent measurements of LaForge \textit{et al} [J. Phys. B \textbf{46} 031001 (2013)] for the DDCS and Hubele \textit{et al} [Phys. Rev. Lett. \textbf{110} 133201 (2013)] for the FDCS, respectively. For O$^{8+}$ impact inclusion of the heavy particle (NN) interaction in the calculations is crucial and effects of polarization due to the presence of the projectile ion have also to be taken into account for getting very good agreement with the measured data. Our calculation reproduces the satellite peak structure seen in the FDCS for the Li(2s) measurement, which we explain as being formed by a combination of the binary and NN interactions.