Abstract
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 [Formula: see text] gauge boson have been well studied in an extensive mass range, the [Formula: see text] gauge boson has not been fully investigated yet. We consider the gauge boson of the [Formula: see text] in a wide mass range [Formula: see text] and investigate the constraints on its coupling from various experiments, discussing the similarities and differences from the dark photon and the [Formula: see text] gauge boson.
Highlights
Looking back in history, we can see each discovery of a new fundamental interaction has made huge impact in our understanding of the physical world
While the dark photon 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
As shown in the figure, the strongest bound on the U (1)L gauge boson for mZ ∼< 0.1 eV is from the fifth force search experiments (EP, inverse-square law (ISL), Casimir), which is one of the distinct features from the dark photon scenario
Summary
We can see each discovery of a new fundamental interaction has made huge impact in our understanding of the physical world. While heavy neutral gauge bosons of electroweak or TeV scale have been a traditional discovery target in high energy collider experiments, there is a growing interest of a very light gauge boson as well For such a light gauge boson to survive all the experimental constraints, it should have extremely weak couplings to the standard model (SM) particles, which is one of the reasons it is often called a dark gauge boson. We study the U (1)L gauge boson, whose charges for the SM particles are the lepton number (0 for quarks, 1 for leptons), and obtain the bounds on the coupling in a wide range of the mass. Because of the chiral anomaly cancellation, the gauged U (1)L introduces the new fermions that couple to the U (1)L gauge boson, and some of these fermions may be a dark matter candidate [18]. For the definiteness, we consider this net mixing is zero
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
