Photo 207.03.80 The target rods were initially of tungsten, later of iridium. Diameters were around 3 mm and the lengths 60-110 mm. The rod is embedded in graphite, pressed into an aluminium body with cooling fins for forced air cooling. The 26 GeV proton beam from the PS was focused to the dimension of the rod. To aim precisely at its centre, the target was fitted with a scintillator screen, with circles at every 5 mm radius. Both scintillator and target had to stand pulses of 1.4E13 protons every 4.8 s, without interruption for many months.