Pulse-height defect in the passivated ion-implanted Si detectors of the INDRA array

The pulse-height defect (PHD) of ³⁶Ar, ⁵⁸Ni, ¹²⁹Xe, ¹⁸¹Ta and ¹⁹⁷Au ions in the 180 passivated ion-implanted silicon detectors of the INDRA array has been measured. The detectors faced the target with the low electric field side. The charge encoding ensured a low ballistic deficit. Detectors with the same nominal characteristics and electric field strength show a PHD dependence on the individual silicon wafer. They are classified and calibrated by using an empirical parametrization which relates the PHD to the total energy through a Z-depending power law. A PHD analytical formula, based on a simple recombination model, is also proposed. It considers a realistic charge density variation with the position coordinate on the ion path. This new formula is successfully confronted to some experimental data.