题目：neutrinoless double beta decay and left-right symmetry
Gang Li has received his Ph.D. from Peking University in 2017, and then he worked as a postdoctoral research associate at National Taiwan University (2017-2019). Now he is a postdoctoral research associate at the University of Massachusetts Amherst. He has been working on physics beyond the Standard Model, neutrinoless double beta decay, and collider phenomenology.
The standard model with the addition of 3 light Majorana neutrinos is able to give a positive signal in future neutrinoless double beta decay (NLDBD) experiments for the inverted hierarchy of neutrino masses. However, future cosmological experiments may soon rule out this standard possibility. New physics scenarios have been proposed that would dominate the NLDBD half-life in this case, but current LHC bounds have put stringent constraints on the viable parameter space. Most of those studies made use of old methods for the computation of the decay half-life. In this work, we include a state-of-the-art NLDBD half-life computed using chiral perturbation theory, which includes the long-range pion exchange contributions missed in the literature. For the sake of clarity, we consider the minimal left-right symmetric model of neutrino masses. We conclude that the long-range pion exchange gives the leading contributions to the NLDBD half-life and guarantee good prospects in next-generation ton-scale NLDBD experiments, even when confronted with future cosmological, LHC, and neutrino oscillation experiments. This makes the physics case of ton-scale NLDBD experiments and highlights the necessity of re-examining other studies.