Searching the anomalous electromagnetic and weak dipole moments of the top-quark at the Bestest Little Higgs Model

Abstract

In this paper, using a Bestest Little Higgs Model (BLHM) approach, we obtain bounds on the top-quark electromagnetic and weak dipole moments. These physical observables are sensitive to quantum corrections induced by virtual particles at the one-loop level. The contributions of the virtual particles are obtained from the vertices of scalar bosons, vector bosons, and heavy quarks: $t{q}_i{S}_i$, $S_i=h_0,H_0,A_0,{\varphi }^0,{\eta }^0,\sigma ,H^{\pm },{\varphi }^{\pm },{\eta }^{\pm }$; $t{q}_i{V}_i$, $V_i=\gamma ,Z,W,Z^{\prime },W^{\prime }$; $V{q}_i{\bar{q}}_i$, $V=\gamma ,Z$, $q_i=b,t,B,T,T_5,T_6,T^{2/3},T^{5/3}$; $V{W}_i^{-}{\Phi }_i^{+}$, $W_i\equiv W,W^{\prime }$, ${\Phi }_i^{\pm }={\varphi }^{\pm },{\eta }^{\pm }$; $ZZ{H}_i$, $H_i=h_0,H_0$; $Z{Z}^{\prime }{H}_i$; and $V{W}^{\prime }{W}^{\prime }$. With these new contributions, we evaluated the electroweak dipole moments $a_t$, $a_t^W$, $d_t$ and $d_t^W$ of the top-quark in the diagonalization schemes $y_2>y_3$ and $y_2<y_3$ to the Yukawa couplings. For the BLHM parameters, we choose the following values of $m_{A_0}=1000$ GeV, $m_{{\eta }^0}=100$ GeV, $f=[1000,3000]$ GeV, $F=[3000,6000]$ GeV and $\tan \beta =3$, which give the best sensitivity on the electroweak dipole moments of the top-quark in this context: $a_t=1.39\times 10^{-4}+i6.55\times 10^{-5}$; $a_t^W=6.31\times 10^{-5}-i1.39\times 10^{-5}$ for the $y_2>y_3$ scenario, while $a_t=2.12\times 10^{-4}+i4.49\times 10^{-5}$; $a_t^W=2.13\times 10^{-4}-i1.34\times 10^{-5}$ for the $y_2<y_3$ scenario.

Comments: 77 pages, 67 figures. arXiv admin note: text overlap with arXiv:2208.09090, arXiv:2202.12738