Status of $\mathbb{Z}_3$-NMSSM featuring a light bino-dominated LSP and a light singlet-like scalar under the LZ Experiment

Abstract

In the presence of a light singlet-like scalar, the bino-dominated dark matter (DM) candidate in the $\mathbb{Z}_3$-symmetric next-to-minimal supersymmetric standard model ($\mathbb{Z}_3$-NMSSM) exhibits notable deviations from its counterpart in the minimal supersymmetric standard model (MSSM), both in terms of its inherent properties and the mechanisms determining its relic abundance and detection prospects. Motivated by recent progress in experimental particle physics, this study systematically investigates the implications for the \( \mathbb{Z}_3 \)-NMSSM framework featuring a light bino-dominated DM particle and a light singlet-like scalar, ensuring theoretical consistency with empirical observations. Of particular significance are the latest results from the LUX-ZEPLIN (LZ) direct detection experiment, supersymmetry (SUSY) searches at the Large Hadron Collider (LHC), and precision measurements of the Muon g-2 anomaly at Fermilab, which collectively impose complementary constraints on the model's viable parameter space. A comprehensive parameter scan was conducted using the MultiNest algorithm, incorporating constraints from LZ-2022 data, LHC Higgs analyses, Muon g-2 measurements, and B-physics observables. The analysis reveals that current experimental limits -- particularly those on spin-independent (SI) and spin-dependent (SD) DM-nucleon scattering cross-sections and LHC constraints on electroweakinos -- severely restrict the model. Nevertheless, the framework remains capable of naturally accommodating the observed Z boson and standard model-like Higgs boson masses, accounting for the Muon g-2 anomaly, and inducing sizable corrections to the W boson mass. These results are distinctive to the NMSSM and emerge from the interplay of bino-dominated DM and singlino components, with essential contributions from higgsino.

Figures (7)

• Figure 1: Violin plots showing mass distributions of Higgs bosons, EWinos, and sleptons for the refined samples. The violins are scaled by count. The thick vertical bar at the center indicates the interquartile range, with the white dot representing the median; the long vertical line shows the $95\%$ confidence interval.
• Figure 2: Left: Components of ${\tilde{\chi}_1^0}$ for the refined samples. Right: Projection of the refined samples onto the $\sigma_{\tilde{\chi}_1^0-p}^{SI}-\sigma_{\tilde{\chi}_1^0-n}^{SI}$ plane, with colors representing the values of $N_{15}^2$.
• Figure 3: Left: Projection of the refined samples onto the $\sigma_{\tilde{\chi}_1^0-p}^{SI}-\sigma_{\tilde{\chi}_1^0-n}^{SI}$ plane, with colors representing the values $|N_{13}^2-N_{14}^2|$. Right: Projection onto the $\sigma_{\tilde{\chi}_1^0-n}^{SD}- |N_{13}^2-N_{14}^2|$ plane, with colors denoting values of $\mu_{eff}$.
• Figure 4: In the left panel, the refined samples are projected onto the $\sigma_{eff}^{SI}-\sigma_{\tilde{\chi}_1^0-n}^{SD}$ plane. Grey samples are excluded by both the LZ-2022 limits on SI and SD cross sections. Orange and green samples are excluded by either the SI or SD constraints, respectively, while blue samples remain viable under all constraints. In the right panel, the surviving blue samples from the left panel are projected onto the $(\frac{125 \text{ GeV}}{m_{h_s}})^2 \times C_{{\tilde{\chi}^0_{1}}{\tilde{\chi}^0_{1}}h_s} \times C_{N N h_s} - (\frac{125 \text{ GeV}}{m_{h}})^2 \times C_{{\tilde{\chi}^0_{1}}{\tilde{\chi}^0_{1}} h} \times C_{N N h}$ plane. The color bar indicates the values of $\sigma_{eff}^{SI}$.
• Figure 5: The surviving samples that comply with the LZ-2022 limits are projected onto the $\langle \sigma v \rangle_{x_F}-m_{\tilde{\chi}_1^0}$ plane. Blue dots represent the total annihilation cross section (left axis), while pink, green, orange, red, purple, and cyan dots reprent the fraction of the annihilation channels $\tilde{\chi}_1^0 \tilde{\chi}_1^0 \to W^+ W^-, Z Z, h_1 h_2, h_2 h_2, Z h_1~or~Z h_2$, and $\tau^+ \tau^-$, respectively (right axis).