Electron impact ionization--excitation of Helium

GASANEO, GUSTAVO; ANCARANI, LORENZO U.; MITNIK, DARÍO M.; GÓMEZ, ANTONIO I.; AMBROSIO, MARCELO J.

Bochum

Congreso; Gaseous Electronics Conference (GEC); 2016

Ruhr-University Bochum

We calculate triple differential cross sections (TDCS) for the process of ionization-excitation of Helium by fast electron impact in which the residual ion is left in the n=2 excited state. We chose the strongly asymmetric kinematics used in the experiment performed by Dupré et al. [1]. In a perturbative scheme, for high projectile energies the four-body problem reduces to a three-body one [2] and, within that framework, we solve the time-independent Schrödinger equation with a Sturmian approach [3]. The method, based on Generalized Sturmian Functions (GSF), is employed to obtain the initial ground state of Helium, the single-continuum state and the scattering wave function; for each of them, the GSF basis is constructed with the corresponding adequate asymptotic conditions. Besides, the method presents the following advantage: the scattering amplitudes can be extracted directly in the asymptotic region of the scattering solution, and thus the TDCS can be obtained without requiring a matrix element evaluation.[1] C. Dupré et al. (1992) J. Phys. B 25, 259.[2] M.J. Ambrosio et al. (2014) Phys. Rev. A 89, 012713.[3] G. Gasaneo et al. (2013) Adv. Quantum Chem. 67, 153.To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2016.GEC.MW6.17