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There is a growing interest for the search of new light gauge bosons. The small mass of a new boson can turn various kinds of low-energy experiments to a new discovery machine, depending on their couplings to the standard model particles. It is important to understand the properties of each type of gauge boson and their current constraints for a given mass. While the dark photon (which couples to the electric charges) and the $U(1)_{B-L}$ gauge boson have been well studied in an extensive mass range, the $U(1)_L$ gauge boson has not been fully investigated yet. We consider the gauge boson of the $U(1)_L$ in a wide mass range $m_{Z} approx 0 - 10^{12} ~ev$ and investigate the constraints on its coupling from various experiments, discussing the similarities and differences from the dark photon and the $U(1)_{B-L}$ gauge boson.
This paper includes two main parts. In the first part, we present generalized gauge models based on SU(3)_C x SU(4)_L x U(1)_X (3-4-1) gauge group with arbitrary electric charge of leptons. The mixing matrix of neutral gauge bosons is analysed, the e
The quartic gauge boson couplings in the ${SU(3)}_C otimes {SU(3)}_L otimes {U(1)}_N$ models are presented. We find that the couplings of four {it differrent} gauge bosons may have unusual Lorentz structure and the couplings sastify the tree unitarity requirement at high energy limit.
We derive perturbativity constraints on beyond standard model scenarios with extra gauge groups, such as $SU(2)$ or $U(1)$, whose generators contribute to the electric charge, and show that there are both upper and lower limits on the additional gaug
The models with the gauge group $SU(3)_ctimes SU(3)_L times U(1)_X$ (331-models) have been advocated to explain why there are three fermion generations in Nature. As such they can provide partial understanding of the flavour sector. The hierarchy of
We analyze several signals at HERA and the Tevatron of a light $U(1)_B$ gauge boson ($gamma_B$) coupling to baryon number. We show that the study of the production of $b bar{b}$ pairs at the (upgraded) Tevatron can exclude $gamma_B$ with masses ($m_B