Beam tests of a thin dual-readout calorimeter for detecting cosmic rays outside the Earth's atmosphere

Cosmic ray experiments outside the Earth's atmosphere are subject to very s evere restrictions on the mass of the instruments. Therefore, it is importa nt that the experimental information that can be obtained per unit detector mass is maximized. In this paper, we describe tests of a thin (1.4 lambda (int) deep) hadron calorimeter that was designed with this goal in mind. Th is detector was equipped with two independent active media, which provided complementary information on the showering hadrons. It is shown that by com bining the information from these media it was possible to reduce the effec ts of the dominant leakage fluctuations on the calorimeter performance. (C) 2001 Elsevier Science B.V. All rights reserved.