Atomic collisions: electron detachment and resonant inelastic scattering

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1980

OSTI ID:5423952

Ojha, P C

Part I: Electron detachment in collisions of negative ions, H/sup -/ + He. In conflict from the expectation from a compound state model, observation shows that the detachment cross section increases with energy in the adiabatic region below 2 keV. The compound state model is not appropriate because of a strong s-wave component in the wavefunction allows the extra electron to run away as soon as its state becomes unbound. The detachment cross section increases with the collision velocity because detachment is induced by a breakdown of the Born-Oppenheimer approximation which shifts to larger separations of the nuclei as the collision velocity increases. Part II: Resonance excitation in electron rare gas collisions. A new method is proposed for calculating the positions of resonances and cross sections in electron molecule collisions by enclosing the entire system in a spherical box, thus converting the problem to a bound state problem. It is used to calculate the energies of (np/sup 52/P/sub 3/2,1/2/)(n + l)s(n + l)p/sup 3/P resonances in collisions of slow electrons with Ne, Ar, Kr, and Xe. The problem is simplified by invoking the Grandparent Model (that the resonances consist of two loosely bound electrons outside a compact positive ion core). The model is tested by explaining the Schulz's Law. Cross sections for excitation of Ne and Ar atoms from the ground state to the lowest metastable and uv emitting levels are calculated.

• Research Organization: Yale Univ., New Haven, CT (USA)
• OSTI ID: 5423952
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ANIONS
ARGON
ATOM COLLISIONS
BORN-OPPENHEIMER APPROXIMATION
BOUND STATE
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
ELECTRON COLLISIONS
ELECTRON DETACHMENT
ELECTRON-ATOM COLLISIONS
ELECTRONS
ELEMENTARY PARTICLES
ELEMENTS
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
FERMIONS
FLUIDS
GASES
HELIUM
HYDROGEN IONS
HYDROGEN IONS 1 MINUS
INELASTIC SCATTERING
ION COLLISIONS
ION-ATOM COLLISIONS
IONS
KRYPTON
LEPTONS
NEON
NONMETALS
RARE GASES
RESONANCE
RESONANCE SCATTERING
SCATTERING
VELOCITY
XENON