M-shell x-ray production of gold, lead, bismuth, uranium for incident hydrogen, helium, and fluorine ions

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1982

OSTI ID:5072682

Mehta, R

Incident /sup 1/2= and /sup 4/He/sup +/ ions at 0.3-2.6 meV and /sup 19/F/sup q+/ ions at 25, 27 and 35 MeV were used to study the M-shell x-ray production cross sections of Au, Pb, Bi and U. For the incident fluorine ions, projectile charge state dependence of the cross sections were extracted from measurements made with varying target thicknesses (approx. 1 to approx. 300 ..mu..g/cm/sup 2/). The efficiency of the Si(Li) detector was determined by measuring the K-shell x-ray production of various low Z elements and comparing these values to the prediction of the CPSS theory. The experimental results are compared to the prediction of first Born approximation for direct ionization to the continuum and to the OBK of Nikolaev for the electron capture to the K-, L-, M-...shells of the incident ion. Comparison is also made with ECPSSR theory that accounts for the energy loss, Coulomb deflection, and relativistic effects in the perturbed stationary state theory. The first Born calculations are found to overpredict the data at all energies for the targets and projectiles studied here. For /sup 1/H/sup +/ and /sup 4/He/sup +/ data, the ECPSSR calculations agree with the data at approx. 0.35 MeV/u, overpredicts at lower E/sub 1//A/sub 1/ and underpredict it at higher E/sub 1//A/sub 1/. The electron capture contributions to the target ionization is less than 3.4 percent. The enhancement in the target M-shell x-ray production cross section for fluorine ions with K-shell vacancies over those without any K-shell vacancies is attributed to the formation of target M-shell vacancy via the electron capture into the K-shell of the projectile. Good agreement between the data and the prediction of ECPSSR theory supports this fact.

• Research Organization: North Texas State Univ., Denton (USA)
• OSTI ID: 5072682
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ACTINIDES
ATOM COLLISIONS
BISMUTH
BORN APPROXIMATION
CAPTURE
CHARGED PARTICLES
COLLISIONS
COMPARATIVE EVALUATIONS
CROSS SECTIONS
DATA
ELECTROMAGNETIC RADIATION
ELECTRON CAPTURE
ELECTRONIC STRUCTURE
ELEMENTS
ENERGY RANGE
EXPERIMENTAL DATA
FLUORINE IONS
GOLD
HELIUM IONS
HYDROGEN IONS
INFORMATION
ION COLLISIONS
ION-ATOM COLLISIONS
IONIZATION
IONIZING RADIATIONS
IONS
K SHELL
LEAD
M SHELL
METALS
MEV RANGE
MEV RANGE 01-10
MEV RANGE 10-100
MEV RANGE 100-1000
NUMERICAL DATA
RADIATIONS
TRANSITION ELEMENTS
URANIUM
X RADIATION