Computer aided design schematic of the experimental setup (adapted from Salter et al. 2009). The particles are stored in a copper colosseum (1) which sits on top of a 45 kg copper block (2) which acts as a thermal reservoir. The copper is passively cooled by passing liquid nitrogen through a feedthrough cooling ring (3) prior to take off. The particles are kept within the colosseum and protected from radiative heating by a copper shield (4). To initiate a collision, the colosseum is rotated (5) to line up two colosseum holes with two diametrically opposed hydraulic pistons (6). The entire set up is enclosed within a vacuum chamber (7).