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An experimental study of 500- and 1000-eV incident electrons transmitted through a micrometer-sized funnel-shaped (tapered) glass capillary with inlet diameter 0.80 mm, outlet diameter 0.10 mm, and a length of 35 mm is reported. The properties of the electron beam transmitted were measured as a function of the emerging angle and the incident energy dependence. The angular profiles were found to be comprised of up to three peaks for both 500 and 1000 eV showing evidence for transmission going straight through the capillary without interacting with the walls (direct), as well as transmission resulting from Coulomb deflection of the electrons from a negative charge patch or by scattering from nuclei close to the surface of the capillary (indirect). The energy spectra show that elastically transmitted electrons dominate at 500 eV for increasing sample tilt angles up to \ensuremath{\sim}5.0\ifmmode^\circ\else\textdegree\fi{}, while inelastic processes dominate for 1000 eV already at tilt angles of \ensuremath{\sim}1.0\ifmmode^\circ\else\textdegree\fi{}. The angular width of the emitted electrons was found to constitute a narrow beam for direct (\ensuremath{\sim}0.4\ifmmode^\circ\else\textdegree\fi{}) and indirect (0.6\ifmmode^\circ\else\textdegree\fi{} for 500 eV and 1.0\ifmmode^\circ\else\textdegree\fi{} for 1000 eV) transmission for both energies with the widths decreasing for the largest tilt angles measured and approaching the inherent resolution (\ensuremath{\sim}0.3\ifmmode^\circ\else\textdegree\fi{}) of the electron analyzer.

An improved search for a $T$-violating transverse muon polarization $({P}_{T})$ in ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{\ensuremath{\mu}}^{+}\ensuremath{\nu}$ decay was performed using kaon decays at rest. By means of this method, ${P}_{T}$ was extracted with small systematic errors, ${P}_{T}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}0.0042\ifmmode\pm\else\textpm\fi{}0.0049(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.0009(\mathrm{syst})$, and the $T$-violation parameter was determined to be $\mathrm{Im}\ensuremath{\xi}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}0.013\ifmmode\pm\else\textpm\fi{}0.016(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.003(\mathrm{syst})$.

Dynamic features of the guiding of ${\mathrm{Ne}}^{7+}$ ions through nanocapillaries in insulating PET polymers were investigated for incident energies from $3.5\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}7\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$. The deflection angle of the transmitted ${\mathrm{Ne}}^{7+}$ ions shows a few oscillations before approaching an equilibrium value. The experimental results are interpreted in terms of a scenario where the deflection angles of transmitted ions are governed by charge patches formed on the inner wall of the capillary. In addition, the memory effects of different charge patches retained from previous irradiations are studied.

The transmission of highly charged ions through nanocapillaries in insulating polyethylene terephthalate (PET) polymers was investigated. In experiments at laboratories in RIKEN (Japan) and HMI (Germany) different detection methods were applied to study the ion current dependence in a wide range covering two orders of magnitude. At HMI an electrostatic ion spectrometer was used and at RIKEN a two-dimensional position sensitive detector was implemented. New PET samples with parallel capillaries and low density were manufactured. For tilted capillaries, the ions are guided along the capillary axis, since the majority of ions are deflected in a charge patch created in the capillary entrance. The results provide insights into the mechanisms of capillary guiding. The fraction of transmitted ions was found to be nearly independent on the incident ion current indicating a sudden increase in the discharge current depleting the entrance charge patch. The experimental results were well-reproduced by model calculations based on a nonlinear (exponential) expression for the discharge current.