Speaker
Sang Hui Im
(CTPU, IBS)
Description
We examine the possibility to experimentally distinguish three different classes of axion models, i.e. KSVZ-like, DFSZ-like, and string-theoretic axions by observing a different pattern of low energy couplings to the photons, nucleons and electrons. For this purpose, we study the renormalization group running of axion couplings at leading order. We find that the low energy couplings of string-theoretic axions have a similar pattern as those of KSVZ-like axions but yet reveal a sizable difference which might be testable in future axion search experiments. We also note that the coupling of KSVZ-like QCD axions to the electron is dominated by a three-loop contribution involving the exotic heavy quark, gluons, top quark and Higgs field.