Elastic electron scattering from helium: absolute experimental cross sections, theory and derived interaction potentials

Abstract

The authors report new differential cross section measurements (E0=1.5-50 eV) and coupled channel optical model calculations for elastic scattering of electrons from helium. The experimental results, from a crossed electron-atomic beam apparatus are analysed via a complex phaseshift technique with the derived phaseshifts, and their associated errors, then being used to derive total elastic, total reaction, total momentum transfer and grand total cross sections, and their respective errors, in a mathematically rigorous manner. Further, the authors applied fixed-energy inverse scattering techniques to the present data in order to deduce the interaction potential between the colliding particles.

Physical Processes Related to Discharges in Planetary Atmospheres

“…We have not found this level of agreement in the open literature (see e.g. Brunger et al 1992). Table 6 lists the various inelastic interactions along with their associated energy loss terms.…”

Experimental and theoretical study of free–free electron–helium scattering in a CO2laser field

“…We used an R-matrix inner region of radius 40 a 0 and included total angular momenta up to L = 10, with 20 continuum orbitals per angular momentum. In figure 2, we compare the calculated differential cross sections at 20 eV and 25 eV with those measured by experiment [28,29]. The agreement is very good for scattering angles larger than about 40…”

A Critical Comparison of Electron Scattering Cross Sections measured by Single Collision and Swarm Techniques

“…In Fig. 2 the DCS measurements of Brunger et al . (1992) at 1 · 5 eV are compared with the theory of Nesbet and the recent convergent-close-coupling calculation of Fursa and Bray (1995).…”