Constraints on the MSSM from the Higgs Sector - A pMSSM Study of Higgs Searches, Bs -> mu+ mu- and Dark Matter Direct Detection

TL;DR

This study investigates how MSSM viability is constrained by Higgs-sector data in conjunction with rare $B$ decays and dark matter direct detection. By scanning a 19-parameter pMSSM with ~40 million points, the authors quantify how $M_h$ and Higgs couplings are shaped by SUSY parameters and identify two guiding scenarios: a SM-like Higgs with $123< M_h<127$ GeV and a suppressed-rate Higgs, each producing distinct wedges in the $(M_A,\tan\beta)$ plane. They project current and future bounds from LHC searches in the gluino/squark sector, $A^0\to\tau\tau$, $B_s\to\mu\mu$, and XENON100 DM detection, showing that Higgs-sector constraints can outperform direct sparticle searches in excluding large portions of parameter space. The results highlight how future Higgs-rate measurements, invisible decays, and targeted searches for $A^0/H^0$, light neutralinos, and light third-generation squarks will decisively test the MSSM landscape independent of the masses of the first two generation squarks or gluinos.

Abstract

We discuss the constraints on Supersymmetry in the Higgs sector arising from LHC searches, rare B decays and dark matter direct detection experiments. We show that constraints derived on the mass of the lightest h0 and the CP-odd A0 bosons from these searches are covering a broader fraction of the SUSY parameter space compared to searches for strongly interacting supersymmetric particle partners. We discuss the implications of a mass determination in the range 123 < Mh < 127 GeV, inspired by the intriguing hints reported by the ATLAS and CMS collaborations, as well as those of a non-observation of the lightest Higgs boson on MSSM scenarios not excluded at the end of 2012 by LHC and direct dark matter searches and their implications on LHC SUSY searches.

Figures (12)

• Figure 1: The ratio of the branching fraction for $h^0 \rightarrow \gamma \gamma$ (upper panel) and $W^+ W^-$, $Z^0Z^0$ (lower panel) to the SM prediction, obtained with HDECAY, as a function of the lightest neutralino mass for pMSSM points with $A^0$ boson, $\tilde{t}_1$ and $\tilde{b}_1$ masses above 500 GeV. The dashed and full vertical bars give the full range of values for pMSSM points before and after applying the constraint on the $Z^0$ invisible width, respectively.
• Figure 2: Fraction of accepted pMSSM points not excluded by the SUSY searches on 1 (filled circles) and 15 fb$^{-1}$ of LHC data at 7 TeV (open circles) and at 8 TeV (open squares) as a function of the mass of the lightest squark of the first two generations (upper left panel), of the mass of the scalar top $\tilde{t}_1$ (lower left panel), of $\tan \beta$ (upper right panel) and of the mass of the lightest neutralino $\tilde{\chi}^0_1$ (lower right panel).
• Figure 3: Distribution of pMSSM points after the $A^0 \rightarrow \tau^+ \tau^-$ search projected on the $M_A$ (upper panel) and ($M_A , \tan \beta$) plane (lower panel) for all accepted pMSSM points (medium grey), points not excluded with 1 fb$^{-1}$ of data (dark grey) and the projection for the points not excluded with 15 fb$^{-1}$ of data (light grey). The dashed line on the ($M_A , \tan \beta$) plot indicates the 95 % C.L. limit derived by CMS in the $M_h$-max scenario with $M_{\mathrm{SUSY}}$ = 1 TeV for 1.1 fb$^{-1}$.
• Figure 4: Distribution of pMSSM points after the $B_s \rightarrow \mu^+ \mu^-$ constraint projected on the $M_A$ (upper panel) and ($M_A , \tan \beta$) plane (lower panel) for all accepted pMSSM points (medium grey), points not excluded by the combination of the present LHCb and CMS analyses (dark grey) and the projection for the points compatible with the measurement of the SM expected branching fractions with a 20% total uncertainty (light grey).
• Figure 5: Distribution of pMSSM points after the dark matter direct detection constraint projected on the $M_A$ (upper panel) and ($M_A , \tan \beta$) plane (lower panel) for all accepted pMSSM points (medium grey), points not excluded by the current XENON-100 data (dark grey) and the projection for the XENON sensitivity at the end of 2012 (light grey).