Normal spectral emissivities of liquid copper, liquid gold and liquid silver at 684.5 nm

A μs-DOAP (division-of-amplitude photopolarimeter), operating without any moving devices, within a pulse-heating setup is used to access normal spectral emissivity at the melting-point and in the liquid phase. Within this study, measurements were performed for noble metals gold and silver as well as for copper, reporting normal spectral emittance at the melting-point at 684.5 nm and at 1570 nm and normal spectral emittance in the liquid phase at 684.5 nm. As can be seen from the results, all three materials under investigation show (compared to other pure metals) low emissivities at the melting-point and display an increasing behavior in the adjacent liquid state.