Positron Polarization at the International Linear Collider

TL;DR

This paper discusses the benefits of adding polarized positron beams to the International Linear Collider, enhancing new physics searches through improved interaction identification and CP-sensitive observables, especially with transverse polarization.

Contribution

It advocates for upgrading the collider with polarized positron beams and explores their impact on new physics detection and CP violation studies.

Findings

Positron polarization improves fermion-pair production analysis.

Transverse polarization offers additional advantages in new physics searches.

Enhanced sensitivity to CP-violating observables.

Abstract

We review some recent arguments supporting the upgrade of the International Linear Collider by a polarized positron beam, in addition to the polarized electron beam. The examples presented here mainly focus on the impact of positron polarization on items relevant to new physics searches, such as the identification of novel interactions in fermion-pair production and the formulation of new CP-sensitive observables. In particular, in addition to the benefits from positron and electron longitudinal polarizations, the advantages in this field of having transverse polarization of both beams are emphasized.