Electroweak Precision Tests On the MSSM and NMSSM Constrained at the LHC

TL;DR

This paper investigates how electroweak precision tests constrain the parameter spaces of the MSSM and NMSSM models at the LHC, revealing key differences in their behavior and implications for supersymmetry searches.

Contribution

It provides a comparative analysis of MSSM and NMSSM constraints from electroweak precision tests, highlighting how parameters like $ aneta$ influence their viability.

Findings

High $ aneta$ values are excluded in MSSM by EWPTs.

NMSSM points tend to align closer to the SM reference with increasing $R_{ ext{gamma}}$.

Neutralino and chargino contributions are more suppressed in MSSM than in NMSSM.

Abstract

Following previous works regarding electroweak precision tests in supersymmetry, we continue to explore their implications to the MSSM and NMSSM both of which are tightly constrained by the Higgs mass and its decay experiments at the LHC. We adopt universal squark, slepton mass of three generations, and A-term of all SM fermions. We determine the flows of both MSSM and NMSSM in the $S$-$T$ plane with increasing $\tan\beta$ and/or $\gamma\gamma$ rate. Either increasing the value of $R_{\gamma}$ or $\tan\beta$, we find that the benchmark points tend to be pushed outside the contour at 99% CL in the MSSM, however, conversely they tend to shrink towards to the SM reference point in the NMSSM. In particular, $\tan\beta\gtrsim 50$ is excluded at 99% CL by the EWPTs for the MSSM due to this behavior. This behavior is also useful to distinguish the NMSSM from the MSSM. A byproduct is that the contributions coming from the neutralinos and charginos should be more suppressed in the MSSM in comparison with the NMSSM.