Axion-Like Particles (ALPs) are a generic, calculable, and well motivated extension of the Standard Model with far reaching phenomenology. ALPs that couple only to hypercharge represent one subset such models, coupling ALP both photons $Z$ boson. We examine current constraints on this class models an mass in 100 MeV GeV range, paying particular attention region between 10 GeV, portion parameter...

We offer a pedagogical introduction to axion-like particles (ALPs) as far their relevance for high-energy astrophysics is concerned, from few MeV 1000 TeV. This review self-contained, in such way be understandable even non-specialists. Among other things, we discuss two strong hints at specific ALP that emerge very different astrophysical situations. More technical matters are contained three A...