Study of spin-dependent electron impact excitation of Hg(63P1) sublevels by means of polarised-electron-photon coincidences

Electron impact excitation of the Hg(6 3 P 1 ) sublevels has been studied by combining the techniques of electron-photon coincidences and polarised electron scattering. A light polarisation filter allowed the separate observation of the M j =0 and M j =+or-1 sublevel excitation. Spin-up-down asymmetries were measured at collision energies of 8 and 15 eV and scattering angles ranging from 5 to 120'. A variety of parameters and observables have been calculated from experimentally determined state multipoles which yield detailed information about the influence of different spin-dependent interactions on electron impact excitation.