FIZIKA A 8 (1999) 2 , 51-64

size 148kBsize 297kB

THEOREM ON SEPARATION OF COUPLED DIFFERENTIAL EQUATIONS, RESONANCE EFFECTS AND THRESHOLD BEHAVIOUR

SMAIL BOUGOUFFA

Faculty of Science and Engineering, University of Science and Technology, P. O. Box 14353, SANA'A, Yemen

CAO XUAN CHUAN and PAUL FAUCHER

URA 1362du CNRS, Observatoire de la cote d'Azur, B. P. 229, F-06304, Nice Cedex, France

Received 7 January 1999; Accepted 2 November 1999

The aim of this work is to show the importance of the theorem on the separation of coupled differential equations in elastic scattering when the electron energy is below the threshold necessary to produce excitation of the state 1 from the ground state 0. We apply a schematical model to study the resonance effects in electron-hydrogen scattering. We are concerned with the behaviour of various cross-sections in the neighbourhood of the threshold of a new mode of scattering in which the electron possesses any quantized angular momentum, and examine the effects of the change in the centrifugal potentials in the case 1s-2s-2p close-coupling approximation. We conclude by discussing the threshold behaviour and its relation to resonance effects.

PACS numbers: 34.80.Bm
UDC 539.186
Keywords: electron-hydrogen scattering, theorem on the separation of coupled differential equations, scattering near thresholds, resonance effects
Copyright by The Croatian Physical Society
For problems or questions please contact fizika@fizika.hfd.hr