New Constraints on Light Vectors Coupled to Anomalous Currents.

Area of Science:

• High Energy Physics
• Particle Physics
• Beyond Standard Model Physics

Background:

• Standard Model (SM) fermions are subject to interactions with new light vector bosons.
• Chiral anomalies can break SM currents, influencing these interactions.
• Heavy fermions are known to cancel anomalies, leading to specific low-energy interactions.

Purpose of the Study:

• To derive new constraints on light vector bosons coupled to SM fermions.
• To investigate the impact of chiral anomaly cancellation by heavy fermions on low-energy interactions.
• To explore enhanced decay rates for specific processes involving these new vectors.

Main Methods:

• Derivation of low-energy effective interactions from heavy fermion anomaly cancellation.
• Analysis of Wess-Zumino-type interactions between new vectors and SM gauge bosons.
• Calculation of decay rates for Z bosons and flavor-changing neutral current meson decays.

Main Results:

• Identified Wess-Zumino-type interactions arising from anomaly cancellation.
• Demonstrated (energy/vector mass)^2 enhanced rates for processes involving the longitudinal mode of the new vector.
• Showcased (weak scale/vector mass)^2 enhanced rates for Z decays and meson decays via a vector coupled to baryon number.

Conclusions:

• The derived enhanced rates lead to significantly stronger coupling bounds for new vectors compared to existing literature.
• These bounds are effective over a wide range of potential vector masses.
• The study provides a novel avenue for searching for new physics beyond the Standard Model.