TAILIEUCHUNG - Kinetic mixing in models with an extra abelian gauge symmetry
In this paper, the formulation of theories extended by an additional Abelian gauge symmetry in the superfield formalism is presented. By rotating in the space of the gauge fields, the gauge kinetic mixing term can be eliminated, and the relevant charge and coupling are shifted in comparison with the original quantities. We demonstrate, for example, the effect of the gauge kinetic mixing term in the case of the U(1) extension of the minimal supersymmetric standard model. | Communications in Physics, Vol. 28, No. 1 (2018), pp. 41-49 DOI: KINETIC MIXING IN MODELS WITH AN EXTRA ABELIAN GAUGE SYMMETRY TRAN MINH HIEU † Hanoi University of Science and Technology, 1 Dai Co Viet Road, Hanoi, Vietnam † E-mail: Received 17 December 2017 Accepted for publication 17 January 2018 Published 26 March 2018 Abstract. The Lagrangian of a theory possessing two Abelian gauge symmetries may contain a gauge kinetic mixing term without violating any known symmetries. In this paper, the formulation of theories extended by an additional Abelian gauge symmetry in the superfield formalism is presented. By rotating in the space of the gauge fields, the gauge kinetic mixing term can be eliminated, and the relevant charge and coupling are shifted in comparison with the original quantities. We demonstrate, for example, the effect of the gauge kinetic mixing term in the case of the U(1) extension of the minimal supersymmetric standard model. Various physical observables are computed for a given benchmark point. We find that the gauge kinetic mixing is important for the model to predict the observables in a good agreement with experimental data. Keywords: supersymmtry, Abelian gauge symmetry, kinetic mixing. Classification numbers: ; ; . I. INTRODUCTION The standard model (SM) is a successful theory in predicting experimental results. However, there are evidences that this model should be extended to explain experimental anomalies, and to address theoretical problems. To solve these issues, physics beyond the SM is necessary. Extensions of the SM usually imply the extension of the particle content, or that of the symmetry. If a grand unification theory (GUT) is assumed at high energies, there might be some remnant symmetries beside the SM gauge symmetry at lower energies. One possibility is that an additional U 0 (1) symmetry is left after the GUT gauge group is broken down [1, .
đang nạp các trang xem trước
