Neutrino Oscillations and Scalar Non-Standard Interactions at ESSnuSB

Abstract: This report consists of two parts. Firstly, an introduction to neutrino oscillations is presented. This includes introducing neutrino mass terms into the standard model, the leptonic mixing matrix, neutrino oscillations in vacuum and neutrino oscillations in matter. Furthermore, the concept of scalar non-standard interactions is introduced and how neutrino oscillations are altered by them. Secondly, scalar non-standard interactions are investigated in the context of the ESSnuSB experiment. The investigation is done using the GLoBES software package. With it we investigate the effects of scalar non-standard interaction on the probability curves, we check the sensitivity of the scalar non-standard interaction parameters at ESSnuSB, with which we can determine the expected three sigma range of ESSnuSB for the real diagonal SNSI parameters. Finally we look at the main question this report is investigating, which is how the SNSI parameters affect the ability for ESSnuSB to claim charge-parity violation. We find that SNSI can have a significant effect on the ability for ESSnuSB to claim charge-parity violation in the lepton sector. For certain values of the SNSI parameters, delta CP is suppressed in the oscillation probability, resulting in a drastic worsening of this ability.