π-meson production cross-sections as a function of incident proton kinetic energy T_p < 2 GeV. The most important channels for π⁺-meson production are the pp → pnπ⁺ (red line) and the pp → Dπ⁺ (cyan line) channels. The experimental data points are from Machner & Haidenbauer (1999); the black dash line shows the total pp→ π⁺ cross-section. The cross-sections for the pp → π⁰ and pp → π⁻ reactions are shown with grey and blue colours, respectively. The parametrisation for the pp → π⁰ and the respective compiled data are taken from Kafexhiu et al. (2014). The experimental data for pp → π⁻ and the eye-guiding blue dash line are taken from Skorodko et al. (2009). For comparison, the Dermer (1986b) parametrisation for pp → π⁻ cross-section is also shown. This parametrisation describes well the high-energy data, however, below T_p < 1 GeV it deviates significantly from measurements.