|
|
The OPAL Barrel and Endcap Hadron Calorimeters |
The barrel hadron detector consists of 9 layers of chambers, alternating with 8 iron slabs, and spans radii from 3.39 meters to 4.39 meters. The slabs are 100 mm thick with 25 mm gaps. It is closed at each end by a doughnut-shaped endcap, where 8 layers of chambers alternate with 7 slabs of iron. Here the slabs are 100 mm thick with 35 mm gaps. Since there is a high probability of hadronic interactions being initiated in the 2.2 interaction lengths of material before the hadron calorimeter, the overall hadronic energy has to be determined by combining signals from the electromagnetic and hadronic calorimeters.
OPAL calorimeters
The poletip hadron calorimeters