Direct stau production at the LHC

TL;DR

This paper analyzes the production mechanisms of supersymmetric scalar taus at the LHC, highlighting how certain processes can significantly increase expected cross sections and impact experimental search strategies.

Contribution

It provides a comprehensive calculation of stau pair production cross sections in the MSSM, including left-right mixing and additional production channels like b-quark annihilation and gluon fusion.

Findings

b-quark annihilation and gluon fusion can boost cross sections by over tenfold

regions with small stau yields are challenged by recent CMS limits

enhanced production channels influence long-lived stau search strategies

Abstract

We investigate the direct production of supersymmetric scalar taus at the LHC. We present the general calculation of the dominant cross section contributions for hadronic stau pair production within the MSSM, taking into account left-right mixing of the stau eigenstates. We find that b-quark annihilation and gluon fusion can enhance the cross sections by more than one order of magnitude with respect to the Drell-Yan predictions. For long-lived staus, we consider CMSSM parameter regions with such enhanced cross sections and possible consequences from recent searches. We find that regions of exceptionally small stau yields, favoured by cosmology, are in tension with a recent CMS limit on m_stau.