Selected aspects of modeling and observation of cosmic ray showers

Multiple experiments suggest that the current models of high-energy interactions do not correctly predict the number of muons at ground in cosmic-ray initiated air showers. I will present two models aiming to address this issue, one based on the addition of particles with small momenta to some hadronic interactions, the other on the addition of the so-called dark photons to the electromagnetic part of the shower. In an seemingly radical switch of topic, I will also explain the advantages of using stellar photometry for atmospheric monitoring in air-shower experiments, mostly in relation to the aforementioned issues of hadronic interactions.