Determination of excitation matrices of n¹D levels of HeI for Ne⁺-He collisions

Analysis of level-crossing signals after impact excitation of 1snd 3 D levels of He I by He+-He collision

“…By studying the dependence of signal amplitudes on the strength of an electric field 85, often all multipole components of the excitation matrix can be detected. This is true for iL-levels as has been shown previously [5]. With regard to the n3D levels of HeI, the situation is more complicated.…”

“…In two papers published recently [4,5] we reported the complete determination of excitation matrices of lsndtD2 levels of HeI by levelcrossing techniques. Here we are concerned with impact excitation of lsnd3D levels of He I by 35 keV He + -He collisions.…”

Excitation of He—41 D-substates by He+- and Ne+-projectiles investigated by level-crossing techniques

“…Equation (3) follows from the Breit-formula [9] which again is based upon the density matrix formalism. Density operator techniques have to be applied when mixed ensembles of excited atoms are observed.…”

“…we have investigated the magnetic depolarization of the impact induced target fluorescence in an electric field parallel to the magnetic field [9,10]. The energy of the Ne+-ions was varied between 90 keV and 800 keV.…”

“…The transformation can easily be done with standard rotation matrices [12]. In the new system, the change in energy AEm due to perturbation by a magnetic field with a flux density B~ and an electric field of strength e~ is [9,12,15] …”