Study of the energy resolution in the electromagnetic end-caps of the future LDC detector for the ILC

Abstract

The electromagnetic end-caps of the future LDC detector for the ILC ("International Linear Collider") have been simulated with the MOKKA software. The goal of this study is to determine the energy resolution with the classical method, i.e. the energy deposited in 30 + 10 active silicon layers, preceded by 1.4 and 4.2 mm of tungsten placed perpendicularly to the beam axis, respectively. The energy resolution has been fitted by the function $\Delta E/E = a/\sqrt {E} c$ and it was found that a = 12.69 +- 0.17 % GeV$^{1/2}$ and c = 0.839 +- 0.026 % for incident electrons at $\theta$=21.80 degrees and a = 13.33 +- 0.24 % GeV$^{1/2}$ and c = 0.968 +- 0.050 % for incident photons with the same polar angle