Multiple Coulomb Scattering in Thin Silicon

TL;DR

This paper measures multiple Coulomb scattering of electrons in thin silicon, compares results with Geant4 simulations, and introduces a new Student's t distribution model to better describe scattering shape deviations.

Contribution

It provides experimental data on electron scattering in silicon and proposes a novel Student's t distribution model for improved simulation accuracy.

Findings

Good agreement in scattering width between data and Geant4

Large deviations in the shape of scattering distribution

New Student's t distribution model better fits the data shape

Abstract

We present a measurement of multiple Coulomb scattering of 1 to 6 GeV/c electrons in thin (50-140 um) silicon targets. The data were obtained with the EUDET telescope Aconite at DESY and are compared to parametrisations as used in the Geant4 software package. We find good agreement between data and simulation in the scattering distribution width but large deviations in the shape of the distribution. In order to achieve a better description of the shape, a new scattering model based on a Student's t distribution is developed and compared to the data.