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We perform 2.5D hybrid simulations with massless fluid electrons and kineticparticle-in-cell ions to study the temporal evolution of ion temperatures,temperature anisotropies and velocity distribution functions in relation to thedissipation and turbulent evolution of a broad-band spectrum of parallel andobliquely propagating Alfv\'en-cyclotron waves. The purpose of this paper is tostudy the relative role of parallel versus oblique Alfv\'en-cyclotron waves inthe observed heating and acceleration of minor ions in the fast solar wind. Weconsider collisionless homogeneous multi-species plasma, consisting ofisothermal electrons, isotropic protons and a minor component of drifting$\alpha$ particles in a finite-$\beta$ fast stream near the Earth. The kineticions are modeled by initially isotropic Maxwellian velocity distributionfunctions, which develop non-thermal features and temperature anisotropies whena broad-band spectrum of low-frequency non-resonant, $\omega \leq 0.34\Omega_p$, Alfv\'en-cyclotron waves is imposed at the beginning of thesimulations. The initial plasma parameter values, such as ion density,temperatures and relative drift speeds, are supplied by fast solar windobservations made by the \textit{Wind} spacecraft at 1AU. The imposedbroad-band wave spectra is left-hand polarized and resembles \textit{Wind}measurements of Alfv\'enic turbulence in the solar wind. The imposed magneticfield fluctuations for all cases are within the inertial range of the solarwind turbulence and have a Kraichnan-type spectral slope $\alpha=-3/2$. We varythe propagation angle from $\theta= 0^\circ$ to $\theta=30^\circ$ and$\theta=60^\circ$, and find that the minor ion heating is most efficient forthe highly-oblique waves propagating at $60^\circ$, whereas the protons exhibitperpendicular cooling at all propagation angles.

Dissipation of parallel and oblique Alfv\'en-cyclotron waves: implications for minor ion heating in the solar wind