Positron-helium collisions: Positronium formation into an arbitrary excited S state

Journal Article · Sun Nov 30 23:00:00 EST 1980 · Phys. Rev., A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.22.2623· OSTI ID:6781996

Mandal, P; Guha, S; Sil, N C

The scattering amplitude for positronium formation into arbitrary excited S states in positron-helium collisions in which the residual helium ion is left in the ground state, is obtained in a closed form using the first Born approximation and the first-order exchange approximation. Retaining both the post and the prior forms of the interaction potential, cross sections are computed for several incident positron energies in the range 20 --2000 eV. For these energies the asymptotic limit of n/sup 3/ times the cross section as n ..-->.. infinity is attained roughly within 0.1% beyond the excited state 16S.

• Research Organization: Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700032, India
• OSTI ID: 6781996
• Journal Information: Phys. Rev., A; (United States), Journal Name: Phys. Rev., A; (United States) Vol. 22:6; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640303* -- Atomic
Molecular & Chemical Physics-- Positronium
Muonium
& Muonic & Mesic Atoms & Molecules
640304 -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
AMPLITUDES
ATOM COLLISIONS
BORN APPROXIMATION
COLLISIONS
CROSS SECTIONS
ELEMENTS
ENERGY LEVELS
ENERGY RANGE
EV RANGE
EV RANGE 10-100
EV RANGE 100-1000
FLUIDS
GASES
HELIUM
NONMETALS
POSITRON COLLISIONS
POSITRON-ATOM COLLISIONS
POSITRONIUM
PRODUCTION
RARE GASES
S STATES
SCATTERING AMPLITUDES