- 期刊
- OpenAccess
Partial-Wave Analysis of the Electron Bremsstrahlung Spectrum from Atoms
並列摘要
A partial-wave analysis is given for electron bremsstrahlung cross sections from atoms of atomic number Z = 13 and 79 at incident electron kinetic energies T1 between 5 and 500 keV. This study is a first step in learning the behavior of the unpolarized partial-wave cross sections dol1 ,l2 and dol corresponding to specified incident-electron (l1) and final-electron (l2) orbital angular momentum, from which the photon energy (k) spectrum is obtained by summation. This provides information needed to improve simpler theories and to improve the numerical technique of the partial-wave method.In many of the cases studied there are two peaks in dσl1l2 as a function of l2 for a given l1≠0 and one peak for I1:0t corresponding to the dominance of dipole transitions. The position of the peak shifts to low l2 for higher energies, where the higher multipole terms become more important. For large l1, we find that dσo ∝e¯Γl1, with Γ a constant; in the Sommerfeld theory Γs = In t1/t2 where T2 = T1-k.For small l1. the reduced cross section (a^2/kl1^2)dσl1 is a function of kl1^3/a^2, where a = Za, as in the classical theory of Kramers.