Existence of zeros in continuum-continuum matrix elements

Journal Article · Wed May 01 04:00:00 EDT 1996 · Bulletin of the American Physical Society

OSTI ID:394152

Oh, Sung Dahm ^[1]; Shaffer, C D; Pratt, R H ^[2]

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1. Sookmyung Women`s Univ., Seoul (Korea, Democratic People`s Republic of)
2. Univ. of Pittsburgh, PA (United States)

The authors discuss conditions for existence of zeros in the radiative continuum-continuum dipole matrix elements for electron-atom (inverse) bremsstrahlung. They reproduce previous results for this matrix element in the soft photon limit in terms of differences of scattering phase shifts. Using Coulomb wavefunctions they obtain the sign of the matrix element in the limit that one electron energy is taken to infinity while the other remains fixed. With a knowledge of the sign of the matrix elements in these limits, they show that zeros must occur in the s-p matrix element for many atoms. They give an example of a case where this matrix element dominates thus leading to a minimum in the total cross section. They discuss situations in which such minima are related to Ramsauer-Townsend minima in elastic scattering.

• OSTI ID: 394152
• Report Number(s): CONF-9605105--
• Journal Information: Bulletin of the American Physical Society, Journal Name: Bulletin of the American Physical Society Journal Issue: 3 Vol. 41; ISSN BAPSA6; ISSN 0003-0503
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ELECTRON-ATOM COLLISIONS
MATRIX ELEMENTS
RAMSAUER EFFECT