Chen Abstract

The Standard Model has been tested experimentally to a high degree of accuracy. Despite its successes in describing particle interactions at very short distances, it has many glaring deficiencies. Among these are the many free parameters that parametrize fermion masses and mixings. The origin of fermion mass hierarchy and mixing still remains one of the great mysteries in particle physics. Even though the fermion masses are generated by the Higgs mechanism, the Higgs mechanism by itself does not explain the observed mass hierarchy and mixing patterns. The discovery of non-zero neutrino masses leads to yet another puzzle: why the neutrino masses are so small when compared to other fermions, and why two of the three neutrino mixing angles are so large when compared with their quark counterpart. Furthermore, CP violation in the Standard Model is insufficient to explain the observed cosmological baryon number asymmetry. On the other hand, the recent observation of a large value for the third neutrino mixing angle implies good future experimental prospects for discovering a new source of CP violation in the neutrino sector. This new CP violation source may be relevant for the dynamical generation of the cosmological matter-antimatter asymmetry.

In this talk, I will discuss how these outstanding questions in particle physics can be addressed by new physics beyond the Standard Model. I will describe different classes of neutrino mass models and their phenomenological predictions. I will point out a novel interesting possibility that for certain discrete symmetries, CP violation can be entirely group theoretical in origin, leading to interesting implications for the generation of the matter-antimatter asymmetry in the Universe.

Lopez Abstract

There are a number of current and planned experiments to make precision measurements of neutrino oscillations over distances of hundreds of kilometers using man-made beams. In order to continue improving upon current results, these experiments must have a detailed understanding of neutrino interactions with nuclei. This talk will present a recent measurement of the cross section of muon neutrino charged-current interactions on water with no pions in the final state. The measurement uses the ND280 off-axis near detector of the T2K long-baseline neutrino experiment. The charged-current with no pions (CC0π) topology represents one of the most important interaction types for the νμ disappearance analysis at T2K.

Gharibyan Abstract

TBA