Hadron Sampling Total Absorption (STAC) Calorimeters

Abstract

Sampling total absorption detectors for hadrons are an excellent example of the impressive development of particle detectors which has become an essential basis for the breathtaking progress in particle physics. For an energy measurement of hadrons, homogeneous blocks of scintillating or ionization measuring materials are, in contrast to electromagnetic showers, completely impractical since the large hadronic interaction length would lead to huge blocks of material. Hence materials with smaller interaction lengths interleaved with sampling detectors have to be employed. In the sixties, such sampling total absorption counters (STAC) were mostly considered to be useful only for specialized tasks such as neutron detection, and their use as a general purpose detector for hadronic energy measurement was almost laughed at. The advantages of such devices were recognized only in the seventies, where they played a major role, for example, in the collider experiments that discovered the W and Z. Today they have become an almost inevitable ingredient of most existing and planned experiments.