Degradation of resolution in a homogeneous dual-readout hadronic calorimeter

Abstract If the scintillator response to a hadronic shower in a semi-infinite uniform calorimeter structure is S relative to the electronic response, then S / E = [ f em + ( 1 − f em ) ( h / e ) ] , where E is the incident hadron energy, f em is the electronic shower fraction, and h / e is the hadron/electron response ratio. If there is also a simultaneous readout with a different h / e , say a Cherenkov signal C , then a linear combination of the two signals provides an estimator of E that is proportional to the incident energy and whose distribution is nearly Gaussian—even though the S and C distributions are non-linear in E , wide, and skewed. Since an estimator of f em is also obtained, it is no longer a stochastic variable. Much of the remaining resolution variance is due to sampling fluctuations. These can be avoided in a homogeneous calorimeter. The energy resolution depends upon the contrast in h / e between the two channels. h / e is small in the Cherenkov channel. Mechanisms that increase h / e in sampling calorimeters with organic scintillator readout are not available in a homogeneous inorganic scintillator calorimeter . The h / e contrast is very likely too small to provide the needed energy resolution.