Theorie-Palaver

Nov. 22, 2022 at 2 p.m. in Lorentz room (Staudingerweg 7, 5th floor) and via Zoom

Mathias Becker

Sebastian Schenk

Yong Xu

ALP production in weak mesonic decays
Alfredo Guerrera (Padua U. and INFN)


Axion--Like--Particles are among the most economical and well motivated extensions of the Standard Model. In this talk ALP
production from hadronic and leptonic meson decays are studied. The hadronization part of these decay amplitudes has been
obtained using Brodsky--Lepage method or LQCD, at needs. In particular, the general expressions for ALP emission in mesonic
s-- and t--channel tree--level processes are thoroughly discussed, for pseudoscalar and vector mesons. Accordingly, exact
results as well as some useful approximation for meson-to-meson and meson leptonic decay amplitudes are presented.
I will the discuss the phenomenology of various decays and highlight the most robust in terms of experimental searches
and theoretical predictions. Finally, bounds on the (low--energy effective Lagrangian) ALP--fermion couplings are derived,
from present and future flavour experiments. If I have time left I'll also cover some of the new form factors calculations in B mesogenesis.