Module pour l’expérience DELPHI

Two full-size prototypes of sub-units for the DELPHI electromagnetic barrel calorimeter have been built along HPC lines. The converter is made from lead wires glued to both sides of thin fibre-glass strips and folded in a concertina-like fashion. Each wire thus defines a plane through the converter and can be connected to a fixed potential. If this potential is stepped up from wire to wire, the resulting electric field extracts ionization charges from electromagnetic showers or hadrons onto a single-plane multi-wire proportional chamber.