The Next-to-Minimal Supersymmetric Standard Model

TL;DR

The NMSSM extends the MSSM by adding a singlet superfield to solve the μ-problem, yielding a richer Higgs and neutralino sector with distinctive collider and cosmological signatures. The paper analyzes the Lagrangian, tree- and loop-level Higgs masses, and RG running, detailing conditions for viable vacua, domain-wall/tadpole issues, and electroweak baryogenesis. It surveys collider phenomenology across LEP/Tevatron/LHC, as well as B-physics and muon g−2 constraints, highlighting the role of light CP-odd Higgses and Higgs-to-Higgs decays. The review further covers NMSSM variants (cNMSSM, GMSB, nMSSM, U(1)′ extensions), CP and R-parity violation, and NMSSM dark matter, emphasizing how singlino components and new annihilation channels reshape relic density and detection prospects.

Abstract

We review the theoretical and phenomenological aspects of the Next-to-Minimal Supersymmetric Standard Model: the Higgs sector including radiative corrections and the 2-loop beta-functions for all parameters of the general NMSSM; the tadpole and domain wall problems, baryogenesis; NMSSM phenomenology at colliders, B physics and dark matter; specific scenarios as the constrained NMSSM, Gauge Mediated Supersymmetry Breaking, U(1)'-extensions, CP and R-parity violation.

Figures (11)

• Figure 1: Left panel: upper bound on $\lambda$ ($\lambda_\text{max}$) as a function of $\tan{\beta}$ for fixed $\kappa=0.01$. Right panel: $\lambda_\text{max}$ as a function of $\kappa$ for fixed $\tan\beta=10$. Black (lower) bands: light spectrum, red (upper) bands: heavy spectrum. Inside the bands the top quark mass is $171.2 \pm 2.1$ GeV.
• Figure 2: Upper bound on the lightest Higgs mass in the NMSSM as a function of $\tan\beta$ for $m_{t}=178$ GeV ($M_A$ arbitrary: thick full line, $M_A = 1$ TeV: thick dotted line) and $m_{t} = 171.4$ GeV (thin full line: $M_A$ arbitrary, thick dotted line: $M_A = 1$ TeV) and in the MSSM (with $M_A = 1$ TeV) for $m_{t}=178$ GeV (thick dashed line) and $m_{t} = 171.4$ GeV (thin dashed line). Squark and gluino masses are 1 TeV and $A_{t}=A_b=2.5$ TeV. (From Ellwanger:2006rm.)
• Figure 3: Upper bounds on $\xi^2$ from LEP Schael:2006cr, where SM branching ratios $H \to b\bar{b}$ and $H \to \tau^+\,\tau^-$ are assumed. Full line: observed limit; dashed line: expected limit; dark (green) shaded band: within 68% probability; light (yellow) band: within 95% probability.
• Figure 4: Excluded regions in the $\tan\beta$-$M_{A_1}$ plane for $A_t=-2500$ GeV: the gridded region is excluded by LEP, the green (vertically shaded) region is excluded by $\Delta M_{d,s}$, the brown (diagonally shaded) region by $BR(\bar{B}_s\to\mu^+\mu^-)$, the region inside the dashed lines by $BR(\bar{B}\to X_s\mu^+\mu^-)$ with $1~\hbox{GeV}<M_{\mu^+\,\mu^-}<\sqrt{6}~\hbox{GeV}$ or $\sqrt{14.4}~\hbox{GeV}$$<M_{\mu^+\,\mu^-}<m_b$, and the lower yellow corner at $\tan\beta \;\hbox{$>$$\sim$}\; 12$ and small $M_{A_1}$ by $BR(\bar{B} \to X_s \gamma)$ (from Domingo:2007dx).
• Figure 5: Masses of all eigenstates $\eta_i$ of the $\eta_b(nS)- A_1$ system as function of $M_{A_1}$, once $m_{\eta_1}$ is forced to coincide with the BABAR result for $m_{\eta_b(1S)}$ (denoted by $m_\text{obs}$; from Domingo:2009tb).