Study of atomic inner-shell matrix elements with the use of analytic perturbation techniques

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6091125

Gabriel, O V

Nonrelativistic generalized oscillator strengths (GOS) for innershell bound-bound transitions are worked out. Simple analytical expressions are obtained for the momentum transfer dependence of the GOS for an ion of nuclear charge Z. As an illustration of the method, results are presented for K-L transitions in an Fe impurity atom in a very dense hydrogen plasma at high temperatures. Analytic expressions are obtained for radiative rates of transitions between the K and L shells of intermediate- and high-Z elements. These relativistic decay rates can be expressed as power series in the atomic scale parameter lambda which characterizes a small distance expansion of the screened atomic central potential. Retardation effects and all multipole contributions of the radiation field are included. With this approach it is possible to trace explicitly the role of relativistic-retardation and higher multipole corrections to the corresponding nonrelativistic dipole transition rates. Total cross sections which include screening effects are calculated for photoeffect from the inner shells and also an ns subshell of an atom of arbitrary nuclear charge and degree of ionization in the limit of high incident photon energies. An analytic perturbation theory result for the relativistic screening corrections to the modified plane waves which describe the high energy outgoing electrons is also given. Finally, hyperfine splittings of inner-shell atomic energy levels are obtained in a relativistic screened calculation. Screening and relativistic effects can be separately identified in the analytic approach. Screening is for the most part nonrelativistic and largely (though not entirely) enters through the change of the normalization constant.

• Research Organization: Pittsburgh Univ., PA (USA)
• OSTI ID: 6091125
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
640304 -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ANALYTICAL SOLUTION
BOUND STATE
COLLISIONS
CROSS SECTIONS
DATA
ELECTRONIC STRUCTURE
ELEMENTS
ENERGY RANGE
ENERGY-LEVEL TRANSITIONS
HEAVY NUCLEI
HYPERFINE STRUCTURE
IMPURITIES
INFORMATION
IONIZATION
IRON
K SHELL
L SHELL
MATRIX ELEMENTS
METALS
MOMENTUM TRANSFER
NUCLEAR SCREENING
NUCLEI
NUMERICAL DATA
OSCILLATOR STRENGTHS
PERTURBATION THEORY
PHOTON COLLISIONS
RELATIVISTIC RANGE
SCREENING
THEORETICAL DATA
TRANSITION ELEMENTS