LCcal: a calorimeter prototype for future linear colliders

We have constructed a prototype of an electromagnetic calorimeter, for future linear collider experiments, alternating 45 layers of lead and scintillator planes. The scintillation light is collected by means of WLS fibers from square cells of 5/spl times/5 cm/sup 2/. To improve the reconstruction of the shower profile, three silicon pad (/spl sim/0.9/spl times/0.9 cm/sup 2/) detector planes have been inserted between the lead and scintillator layers at 2.6 and 12 X/sub 0/. The prototype has been tested with electron beams at low (50/spl divide/750 MeV) and high energies (5/spl divide/50 GeV): a good linearity in response and an energy resolution of /spl sim/11.5%//spl radic/(E/GeV) have been achieved. A position resolution of 2.5 mm has also been measured for 10 GeV impinging electrons. The calorimeter particle identification capability has been tested comparing electron and pion beams.