Figure 1

Diagram of the apparatus for electron-photon coincidence investigations in the coherence-analysis version. EG: electron gun (Comstock EG-402EL); EEA: electron-energy analyzer (AC–901, Comstock); CH: channeltron (7010M, Photonis); OV: the source of the atomic beam (stainless-steel oven with two-stage collimator); QL: quartz lens; $\lambda /4$: zero-order quartz retardation plate (Melles Griot); POP: “pile-of-plates” polarizer (eight quartz plates); F: broadband filter (213.8 nm, Roper Scientific); PMT: photomultiplier (9235QSB, THORN EMI); CFD: constant-fraction discriminator; SMC: stepper-motor controller; TAC: time-to-amplitude converter; AMP: preamplifier; DLY: delay line; MCA: multichannel analyzer.Reuse & Permissions

Figure 2

Energy-loss spectrum of scattered electrons observed at ${10}^{\circ }$ scattering angle for incident electrons of energy 100 eV.Reuse & Permissions

Figure 3

Typical electron-photon coincidence spectrum accumulated for electron scattering angle $\Theta$ of ${10}^{\circ }$.Reuse & Permissions

Figure 4

Graphical representations of angular distributions of the electron charge cloud of the excited $4{}^1{P}_1$ state of Zn for experimentally obtained values of the EICPs for different scattering angles (from $5^{\circ }$ to 40${}^{\circ }$).Reuse & Permissions

Figure 5

Stokes parameters ($P_1$, $P_2$, and $P_3$) for Zn $4{}^1{P}_1$ state excitation by 100 eV electrons ($•$ experiment; — RDWA theoretical predictions; $\cdots$ CCC theoretical predictions). The measurements of $P_1$ at scattering angle ${25}^{\circ }$ and $P_2$ at ${15}^{\circ }$ were repeated ($\square$).Reuse & Permissions

Figure 6

EICP parameters ($P_L$, $\gamma$, and $P^{+}$) for Zn $4{}^1{P}_1$ state excitation by 100 eV electrons ($•$ experiment; — RDWA theoretical predictions; $\cdots$ CCC theoretical predictions). The first-order Born approximation predictions are also presented ($-·-$) for alignment angle $\gamma$.Reuse & Permissions