Portal de Periódicos da CAPES

Searching the anomalous electromagnetic and weak dipole moments of the top quark at the bestest little Higgs model

2023; Springer Science+Business Media; Volume: 138; Issue: 6 Linguagem: Inglês

10.1140/epjp/s13360-023-04125-8

2190-5444

E. Cruz-Albaro, A. Gutiérrez-Rodríguez, M. A. Hernández-Ruíz, T. Cisneros-Pérez,

Black Holes and Theoretical Physics

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: $$tq_iS_i$$ , $$S_i=h_0, H_0, A_0, \phi ^{0}, \eta ^{0}, \sigma , H^{\pm }, \phi ^{\pm }, \eta ^{\pm }$$ ; $$tq_iV_i$$ , $$V_i= \gamma , Z, W, Z', W'$$ ; $$V q_i{{\bar{q}}}_i$$ , $$V=\gamma ,Z$$ , $$q_i=b, t, B, T, T_5, T_6, T^{2/3}, T^{5/3}$$ ; $$V W^{-}_{i}\Phi ^{+}_i$$ , $$W_{i} \equiv W, W'$$ , $$\Phi ^{\pm }_{i}= \phi ^{\pm }, \eta ^{\pm }$$ ; $$ZZH_i$$ , $$H_i=h_0, H_0$$ ; $$ZZ' H_i$$ ; and $$VW'W'$$ . With these new contributions, we evaluated the electroweak dipole moments $$a_t$$ , $$a^{W}_t$$ , $$d_t$$ and $$d^{W}_{t}$$ 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: $$a_t=1.39 \times 10^{-4} + i\, 6.55 \times 10^{-5}$$ ; $$a^{W}_t=6.31 \times 10^{-5} - i\, 1.39 \times 10^{-5}$$ for the $$y_2 > y_3$$ scenario, while $$a_t= 2.12 \times 10^{-4} + i\, 4.49 \times 10^{-5}$$ ; $$a^{W}_t= 2.13 \times 10^{-4} - i\, 1.34 \times 10^{-5}$$ for the $$y_2 < y_3$$ scenario.