A study of hadron-Pb collisions through hadron-induced showers in thick lead chambers

Structures of hadron-induced showers observed by the Pamir thick lead chamb ers are compared with simulations. The simulations are made for several mod els, VENUS, QGSJET, HDPM and the modified UA5 model, for hadron-nucleus int eractions. A parameter Z, which is related to the inelasticity of hadron-Pb interactions, is defined and the 2-distribution of experimental data is co mpared with those of the simulations applying the same procedure of data pr ocessing to both sets of data. The Z-distribution for single-isolated hadro ns is well reproduced by the models (VENUS, QGSJET and modified UA5) which give an average inelasticity < Kh-Pb> = 0.7-0.8, whereas that for multi had rons is close to the HDPM model which gives a smaller inelasticity of < Kh- Pb> = 0.5-0.6. The difference of the characteristics between the two catego ries of hadron-induced showers is discussed. (C) 2000 Elsevicr Science B.V. Ail rights reserved.