# Accession Number:

## AD0671838

# Title:

## COLLECTIVE EFFECTS AND THE SCATTERING OF ATOMIC BEAMS FROM PLASMAS.

# Descriptive Note:

## Technical rept.,

# Corporate Author:

## NEW YORK UNIV N Y DEPT OF PHYSICS

# Personal Author(s):

# Report Date:

## 1968-05-29

# Pagination or Media Count:

## 47.0

# Abstract:

The possibilities of detecting collective effects in laboratory plasmas through the use of atomic beam scattering experiments are investigated. In the Impulse Approximation the differential cross section for scattering of an atom, with one effective electron, from a two-component plasma is obtained. A model calculation for the scattering of a thermal hydrogen beam from an equilibrium cesium plasma is outlined. An effective range theory is used to describe the atom-electron scattering amplitude and a semi-classical theory is used to describe the atom-ion scattering amplitude. A hydrogen beam of energy .23ev scattering from a cesium plasma with a particle density of 10 to the 14th powercc and a temperature of .23ev is considered. For these values of the beam and plasma parameters the differential cross section is given in terms of the ion and ion-electron static factors plus integrals over the electron coherent and incoherent dynamic form factors. If the Convolution Approximation of Vineyard is used to obtain the electron incoherent dynamic form factor in terms of the electron coherent dynamic form factor, it leads directly to the prediction that the spin-flip cross section will be enhanced as the scattering angle goes to zero. Author

# Descriptors:

# Subject Categories:

- Plasma Physics and Magnetohydrodynamics