Schematic view of the chosen NN architecture. The blue nodes on the left correspond to the four inputs governing the density enhancement and silicon abundance, which are fed into the input layer. The input layer and hidden layer are both comprised of 200 neurons with a softplus activation function and are represented by the grey nodes. Finally, the orange nodes correspond to the normalised luminosity outputs at the 75 wavelength points across the range of the Si IIλ6355 feature.