Comparative study of vibracional excitation of hydrogen molecules by electron and positron impact

Author(s)

Andréia Nalú Soares Hisi

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Física Gleb Wataghin
• Defense date: 2006-03-24

Examining board members

Marco Aurélio Pinheiro Lima; Alex Antonelli; Rogério Custodio

• Advisor: Marco Aurélio Pinheiro Lima

Abstract

Here we report a comparative calculation of both integral and differential vibrational excitation cross sections of low energy positron and electron scattering against Hydrogen molecules (H2). For these calculations we have used the Schwinger Multichannel (SMC) Method [1] for positron collision [2] and electron collision [3]. Using a set of SMC scattering amplitudes, calculated at specific quadrature points (Hermite [4]) of internuclear distances, we have obtained vibrational resolved cross sections in the Adiabatic Aproximation [5]. In order to compare the electron scattering process with the positron one, the scattering amplitudes were calculated with the same basis set for representing the molecular target and scattering particle wave functions. For the vibrational wave functions we have used the eigenfunctions of a simple harmonic oscillator (with the experimental frequency) for both cases, the electron and positron scattering (AU)