Total polarization of the 185 nm emission line of mercury excited by electron impact

Abstract

Results for the three Stokes parameters (polarization components) P 1 , P 2 and P 3 of the VUV Hg transition 6s6p 1 P 1 → 6s 2 1 S 0 (185 nm) obtained from electron-photon (e, eγ ) coincidence measurements at electron impact energies of 15 eV, 50 eV and 100 eV (Aussendorf et al 2006 J. Phys. B: At. Mol. Opt. Phys. 39 2403) were combined to obtain the total degree of polarization3 . In addition, the Stokes parameter P 4 was measured at an electron impact energy of 15 eV. The measured data are compared with predictions from a fullrelativistic distorted-wave calculation, a five-state semirelativistic Breit-Pauli R-matrix (close-coupling) model, and a convergent close-coupling ansatz, where relativistic effects are accounted for by recoupling of nonrelativistic results. In agreement with the theoretical predictions, no influence of the electron spin was observed for scattering angles θ 30• . At 15 eV excitation energy and scattering angles θ 40• , however, an increasing importance of spin effects is predicted.

Application of relativistic coupled cluster theory to elastic scattering of electrons from confined Ca atoms

“…In contrast, RCC theory treats both the core-polarization and pair-correlation effects on an equal footing and includes them to all-orders. Also, DFCP and RCC results might differ significantly for more sensitive scattering parameters, viz, polarization, alignment and orientation parameters, which provide a more sensitive test of a theory [47][48][49][50]. These collision parameters depend upon the magnitude as well as phase of the complex scattering amplitude, whereas, in calculating DCS and ICS the information about phase gets lost as these are obtained by taking the absolute square of the complex amplitude (equation ( 14)).…”

Comparison of experiment and theory for superelastic electron-collision studies from laser-aligned magnesium

“…The electron-photon coincidence technique has been used to study collisions with different atomic targets, both experimentally and theoretically. These include the lighter targets hydrogen [4][5][6], helium [7,8], and magnesium [9,10]; intermediate targets including calcium [11][12][13][14][15][16], neon [17][18][19], and zinc [20][21][22][23]; and heavier targets including cadmium [24][25][26], lead [27], and mercury [28][29][30][31][32][33].…”