Laser effect on the final products of Z-boson decay

Abstract

Experimentalists have long sought a method that allows them to control the branching ratios of an unstable particle decay and direct some decay to follow one specific desired channel without another. The powerful laser could make this a reality. In this letter and within the framework of the standard electroweak model, we investigate theoretically the laser effect on the branching ratios of different Z-boson decay modes by calculating analytically the Z-boson decay into a fermion-antifermion (Z → f f ) pai in the presence of a circularly polarized electromagnetic field. It is found that, at high intensities, the Z-boson could only decay invisibly into neutrinos, and its decay into any other pair of charged fermions becomes impossible due to the increase in the effective mass that fermions acquire inside the electromagnetic field. The influence of the laser frequency and intensity on the lifetime is also included in order to confirm the surprising result obtained for the pion lifetime in a previous paper (Mouslih 2020 Phys. Rev. D 102 073006).

$Z$-boson production via the weak process $e^+e^- \to μ^+μ^-$ in the presence of a circularly polarized laser field

“…Due to the fact that the CP-laser field reduces the maximum cross section (σ max ), we assume that the partial width of the Z-boson decay into electron positron pair production +∞ n=−∞ Γ n e + e − = (M 2 Z Γ 2 Z /12π) × (σ max /Γ µµ ) decreases as a function of the number of exchanged photons for a given laser field's strength and frequency. This result confirms the same behavior obtained in [7], in which the authors show that, at high laser intensity, the CPlaser field decreases the branching ratio of the hadronic and leptonic decay modes of the Z-boson while its invisible decay mode increases. After having discussed the variation of the TCS as a function of the CME for different number of transferred photons, we next focus on how this TCS varies at Z-boson peak ( √ s = M Z ) as a function of the laser field's strength for different laser field's frequencies.…”

“…Now, we proceed by evaluating the partial width decay of Z-boson into pair of electron and positron in the presence of a CP-laser field. These quantity is already evaluated in [7] and it is given by:…”

“…In the framework of electroweak standard model of particle physics [6], the laser assisted scattering processes could have an important impact on the production and decay processes as it affects the measured quantities that characterize the scattering such as the cross section, the branching ratio and life time. In [7], the authors prove that the laser radiation has a significant effect on the final product of the Z-boson decay. In [8], the authors shows that the laser field enhances the life time of the pion and affects its modes decay.…”

Laser-assisted neutral Higgs-boson pair production in Inert Higgs Doublet Model (IHDM)

“…Recently, much attention was devoted to the possibility of using powerful laser fields to test physical theories such as standard model and beyond [3]. This interest is due not only to the rapid development of laser sources but also for the fact that a large of unknown phenomena were induced by laser-matter interaction [4][5][6][7].…”

“…Several weak decay and scattering processes were studied. In [6,10], it is found that the laser field has a great impact on the decay processes as it modify the particles lifetime and affect its decay modes. In our recent work [11] we have found that the total cross section of the Higgs-strahlung process can be largely reduced by several orders of magnitude only in extreme intense electromagnetic fields.…”