Asymptotically Free Natural Supersymmetric Twin Higgs Model

Twin Higgs (TH) models explain the absence of new colored particles responsible for natural electroweak symmetry breaking (EWSB). All known ultraviolet completions of TH models require some nonperturbative dynamics below the Planck scale. We propose a supersymmetric model in which the TH mechanism is introduced by a new asymptotically free gauge interaction. The model features natural EWSB for squarks and gluino heavier than 2 TeV even if supersymmetry breaking is mediated around the Planck scale, and has interesting flavor phenomenology including the top quark decay into the Higgs boson and the up quark which may be discovered at the LHC.

Figure 1

RG running of $g_X$ (red), $g_1$ (blue), $g_2$ (yellow), $g_3$ (green) and the top Yukawa coupling $y_t$ (black) for $m_X=10\mathrm{TeV}$, $m_{\text{stop}}=2\mathrm{TeV}$, $g_X(m_X)=2$, and $\tan \beta =3$. Solid lines correspond to the case where all states beyond the Minimal Supersymmetric Standard Model (MSSM) have masses around $m_X$. Dashed lines assume $M_{E_1}={10}^7$, $M_{E_2}={10}^9\mathrm{GeV}$, see text for details. Dotted black line corresponds to the running of $y_t$ in the MSSM.

Figure 2

Fine-tuning ${\mathrm{\Delta }}_v$ of the model in the plane $\mathrm{\Lambda }\text{−}{g}_X$ for $m_{\text{stop}}=2\mathrm{TeV}$, $\tan \beta =3$, $f=3v$, $\mu =500\mathrm{GeV}$, $M_1=M_2=200\mathrm{GeV}$ and the soft gluino mass $M_3=2\mathrm{TeV}$. We fix ${\epsilon }^2=1/3$ which corresponds to $m_S=m_X$.

Figure 3

Masses of the lightest (right-handed) stop and the right-handed up squark (blue) and the lightest squark of the first generation other than the right-handed up squark (orange) as a function of gluino soft mass parameter $M_3$ defined at the stop mass scale and universal soft scalar mass $m_0$ at the UV scale of $\mathrm{\Lambda }={10}^{16}\mathrm{GeV}$ for $g_X=2$ and ${\epsilon }^2=1/3$. Red contours depict ${\mathrm{\Delta }}_v$.