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

Cosmic ray experiments outside the Earthʹs atmosphere are subject to very severe restrictions on the mass of the instruments. Therefore, it is important that the experimental information that can be obtained per unit detector mass is maximized. In this paper, we describe tests of a thin (1.4λint deep) hadron calorimeter that was designed with this goal in mind. This detector was equipped with two independent active media, which provided complementary information on the showering hadrons. It is shown that by combining the information from these media it was possible to reduce the effects of the dominant leakage fluctuations on the calorimeter performance.