Optical Potential forHe(21S)+Arfrom High-Resolution Differential Scattering Experiments

Abstract

The real and imaginary parts of the interaction potential of metastable $\mathrm{He}\left(2^{1}S\right)$ with argon have been accurately determined from high-resolution differential scattering experiments. The real part of the potential shows an unexpected structure with two minima, while the imaginary part is monotonic, but cannot be expressed by a single exponential.