Speaker
Description
We discuss hadron scatterings in zero temperature and small chemical potential ($\mu$). First, we derive the dispersion relation of a single hadron from the Euclidean-time dependence of the 2-point correlation function. It is found that the energy has linear behavior with respect to $\mu$. We then formulate the HAL QCD method in small $\mu$, where we extract scattering amplitudes via the interaction potentials. It indicates that the amplitude is independent of $\mu$ for any scattering unless the spontaneous breaking occurs. Furthermore, we demonstrate this conclusion by analyzing S-wave scatterings of two pions with isospin $I=2$ and two scalar diquarks in two-color QCD using lattice simulation. The results of the scattering amplitudes in different chemical potentials agree with each other, which is consistent with our conclusion.
