The role of polarized positrons and electrons in revealing fundamental interactions at the Linear Collider

TL;DR

Polarized positron and electron beams at the International Linear Collider significantly enhance the discovery potential for new physics beyond the Standard Model by improving search sensitivity and particle identification.

Contribution

This paper demonstrates the critical importance of beam polarization at the ILC and analyzes its benefits for exploring new physics scenarios and designing polarization measurement systems.

Findings

Positron polarization enhances search sensitivity for new particles.

Polarized beams improve the identification of particle interactions.

Design options for beam polarization and measurement are summarized.

Abstract

The proposed International Linear Collider (ILC) is well-suited for discovering physics beyond the Standard Model and for precisely unraveling the structure of the underlying physics. The physics return can be maximized by the use of polarized beams. This report shows the paramount role of polarized beams and summarizes the benefits obtained from polarizing the positron beam, as well as the electron beam. The physics case for this option is illustrated explicitly by analyzing reference reactions in different physics scenarios. The results show that positron polarization, combined with the clean experimental environment provided by the linear collider, allows to improve strongly the potential of searches for new particles and the identification of their dynamics, which opens the road to resolve shortcomings of the Standard Model. The report also presents an overview of possible designs for polarizing both beams at the ILC, as well as for measuring their polarization.