Heidelberg University

Particle physics at low energies

Ulrich Schmidt, Heidelberg University


Particle physics at low energies is a very broad field with respect to the topics as well as concerning the methods. Consequently my lectures can only touch a special personal selection of topics. I would like to start at the lowest energies that are accessible experimentally, i.e. of the order of 10-26eV. The method to reach this high sensitivity is often called a clock comparison as the experiments utilize spin clocks. The physical topics which can be accessed by this method range from the searches for electric dipole moments (EDMs) of particles, for Axions and Axion-like particles (ALPs) to Lorentz Violation, searches which are at the heart of modern physics. Macroscopic torsion balances are a different method to search for Lorentz Violation as well as Equivalence principle violations and large extra dimensions. The third method I would like to talk about is precision beta decay spectroscopy of the free neutron. Firstly, the results of this method lead to the most precise determination of the parameters of Weak Interaction of the Standard Model in the low energy limit and for the first generation of quarks. Secondly, combining different results of such neutron decay experiments enables the search for physics beyond the Standard Model.