Calculation of cross sections for 2s-2p excitation of one-electron ions by He/sup 2 +/ and He/sup 0/

Journal Article · Sat Nov 01 04:00:00 EST 1980 · Phys. Rev., A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.22.2270· OSTI ID:6939621

McGuire, J H; Simony, P R

Cross sections for 2s-2p excitation of one-electron ions scattering from He/sup 2 +/ and He/sup 0/ are evaluated in the plane-wave Born approximation. The total cross section diverges logarithmically as the 2s-2p binding energy difference ..delta..E goes to zero for excitation by He/sup 2 +/ due to contributions from small momentum transfers. In contrast for He/sup 0/ as ..delta..E goes to zero the total cross section is finite since the small-momentum-transfer contribution is damped corresponding to screening of the nucleus by the helium electrons at large distances. Calculations are presented for 2s-2p excitation of F and Si scattering from He/sup 2 +/ and He/sup 0/ at velocities of several MeV/amu. For F and Si there is about an order of magnitude difference between scattering from He/sup 2 +/ and from He/sup 0/, suggesting that electron screening is important here. However, our results are not in consistent agreement with recent observations.

• Research Organization: Department of Physics, Kansas State University, Manhattan, Kansas 66506
• OSTI ID: 6939621
• Journal Information: Phys. Rev., A; (United States), Journal Name: Phys. Rev., A; (United States) Vol. 22:5; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ALPHA PARTICLES
ATOM COLLISIONS
BINDING ENERGY
BORN APPROXIMATION
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
ELEMENTS
ENERGY
FLUIDS
FLUORINE
GASES
HALOGENS
HELIUM
HELIUM IONS
ION COLLISIONS
ION-ATOM COLLISIONS
ION-ION COLLISIONS
IONS
NONMETALS
RARE GASES
SEMIMETALS
SILICON
TOTAL CROSS SECTIONS