Two-center close-coupling calculations of positron–molecular-hydrogen scattering

Abstract

A two-centre close-coupling method that includes positronium (Ps) formation channels has been developed for positron scattering on molecular hydrogen. Calculations are performed within the fixed-nuclei approximation. Results for the grand total, Ps-formation and direct ionization cross sections are presented. In general, good agreement with experiment is seen in all the calculated cross sections.

Recommended Positron Scattering Cross Sections for Atomic Systems

“…Other two-centre CCC works include positron scattering by helium [60], lithium [61], sodium [62], magnesium [63] and H2 [64]. Several physical parameters such as TCS, and the differential cross section (DCS) for positron scattering by neon, argon, xenon and krypton were calculated using the single centre CCC [65][66][67].…”

Recent progress in the description of positron scattering from atoms using the convergent close-coupling theory

“…The single centre CCC(108, 0) results are due to Zammit et al [196]. The two-centre CCC calculations are due to Utamuratov et al [199].…”

“…[85] and Jacobsen et al [177]. The CCC calculations are due to Utamuratov et al [199]. experimental data.…”

“…Once we have con- [175]. The CCC calculations are due to Zammit et al [196] (one-centre) and Utamuratov et al [199] (two-centre).…”

Electron-impact excitation of molecular hydrogen

“…In this method a single-centre approach to molecular structure is adopted and a Sturmian (Laguerre) single-particle basis is used to represent molecular wave functions. The CCC method has been successfully applied to positron scattering from H 2 [45][46][47] and electron scattering from H + 2 and its isotopologues [48,49]. In both cases the use of a large Laguerre basis allowed us to demonstrate convergence of the calculated cross sections within the FN approximation and perform adiabatic-nuclei (AN) calculations for scattering from the hot (vibrationally) excited states.…”