Speaker
Description
A new type of four-point interaction, $W$-$\ell$-$\nu$-$a$, in an electroweak-violating scenario of axion-like particle (ALP) and lepton interactions plays a critical role in searching for ALPs from charged mesons and W boson decays because of the novel energy enhancements. Inspired by this interesting finding, we first proposed new t-channel processes for electrophilic ALPs (eALPs) which also involve $W$-$\ell$-$\nu$-$a$ four-point interaction and have obvious energy enhancement behaviors in their cross sections when the collision energy is increasing. On the other hand, heavier eALPs mainly decay to a photon pair induced by the chiral anomaly instead of an electron-positron pair. Therefore, studies of these t-channel processes with a photon pair plus missing energy at CEPC open a new door to search for eALPs at high energy colliders. The proposed search strategies are not only aiming to generate a larger production rate of ALPs, but also trying to distinguish electroweak-violating ALP-lepton interactions from electroweak-preserving ones.
