A Study of the Impact of Muons from the Beam Delivery System on the SiD Performance

TL;DR

This study evaluates how different muon shielding configurations in the ILC's Beam Delivery System affect the SiD detector's performance, using detailed simulations to inform optimal shielding design choices.

Contribution

It provides a comparative analysis of muon background impacts with and without a magnetized shielding wall using full detector simulations.

Findings

Omitting the shielding wall increases muon background at the detector.

Shielding scenarios significantly influence detector background levels.

Simulation results support decision-making on muon shielding design.

Abstract

To suppress the muon background arising from the Beam Delivery System (BDS) of the International Linear Collider (ILC), and to hinder it from reaching the interaction region, two different shielding scenarios are under discussion: five cylindrical muon spoilers with or without an additional magnetized shielding wall. Due to cost and safety issues, the scenario preferred by the Machine-Detector-Interface (MDI) group is to omit the shielding wall, although omitting it also has disadvantages. To support the decision making for the muon shielding, the impact of the muons from the two different shielding scenarios was studied in a full Geant4 detector simulation of the SiD detector, one of two proposed detectors for the ILC. Input to this study is the muon background created by the beam traveling through the BDS, which was simulated with MUCARLO.