that the red-shifted lines arise from a radiative Auger process. The evidence in the experiment is compelling based on a number of factors. First, the Auger lines disappear on removing the additional electron – they are absent in the emission spectrum of the neutral exciton, $X^0$ (Supplement). Secondly, the red-shifted emission lines only appear when the laser is in resonance with the QD (Fig. \[fig:mechanism\](b)). Thirdly, the time-resolved cross-correlation between the radiative Auger emission and the resonance fluorescence (Fig. \[fig:mechanism\](d,e)) shows a pronounced anti-bunching at zero time-delay. This quantum optics measurement proves that there is just one emitter, and that the emitter produces either a resonance-fluorescence photon or a radiative-Auger photon, but never two photons at the same time. Finally, to prove that the radiative Auger process leaves an electron in a higher shell, we measure the optical emission as a function of the magnetic field (Faraday geometry). The magnetic field creates an additional orbital confinement, which leads to a strong magnetic field dependence of higher QD-shells [@Kouwenhoven2001; @Fock1928; @Darwin1930]. Therefore, also the radiative Auger emission should have a strong magnetic field dependence. This is exactly what we observe. The magnetic field dispersion of the radiative Auger emission is shown 