Determination of sparticle masses and SUSY parameters

TL;DR

This study evaluates how a representative mSUGRA scenario can be probed with high precision at the TESLA Linear Collider. By leveraging polarized e+e− collisions, end-point lepton spectra, di-lepton/di-jet edges, and threshold scans, it demonstrates sub-GeV to sub-0.1 GeV mass resolutions for sleptons, neutralinos, and charginos. It then shows that these precise masses enable stringent top-down RG analyses, yielding per-mil constraints on m0, m1/2 (and M1/M2 when allowed to vary) and percent-level constraints on tanβ and A0. The findings highlight the crucial role of high luminosity and beam polarization in testing SUSY-breaking mechanisms and approaching GUT-scale physics. Overall, the work illustrates TESLA’s potential to reconstruct the SUSY spectrum and underlying parameters with remarkable precision.

Abstract

A case study will be presented to determine the particle masses and parameters of a specific mSUGRA model at the TESLA Linear Collider with high precision.

Figures (4)

• Figure 1: Mass spectrum and decay modes of sleptons and light gauginos
• Figure 2: Examples of slepton production. Lepton energy spectra of $\tilde{\mu}_R \to \mu \chi^0_1$ at $320~{\rm GeV}$ (upper left), $\tilde{\mu}_L \to \mu \chi^0_2$ at $500~{\rm GeV}$ (upper right) and $\tilde{\nu}_{e} \to e^\mp \chi^\pm_1$ at $500~{\rm GeV}$ (lower left). Di-jet mass spectrum of $\chi^\pm_1 \to q \bar{q}' \chi^0_1$ (lower right).
• Figure 3: Di-lepton mass and energy spectra of $\chi^0_2 \to l^+ l^-\,\chi^0_1$ at $320~{\rm GeV}$ (left part) and di-jet mass and energy spectra of $\chi^\pm_1 \to q \bar{q}' \chi^0_1$ at $320~{\rm GeV}$ (right part).
• Figure 4: Visible cross sections near threshold of the reactions $e^-_R e^+_L \rightarrow \tilde{\mu}_R \tilde{\mu}_R$ (left) and $e^-_L e^+_R \rightarrow \chi^-_1 \chi^+_1$ (right). Measurements assume ${\cal L} = 10~{\rm fb}^{-1}$ per point.