Neutrons and Fundamental Symmetries: Fundamental Electroweak and Hadronic Physics Studies of the Neutron

The driving central theme of our proposed research program concerns low-energy, high-precision tests of the fundamental symmetries underlying the theory of the electroweak interaction. With ul- tracold neutrons, we will carry out a new sensitive search for the Time-Reversal-Symmetry-violating neutron electric dipole moment, and also a precision measurement of parity-violation in neutron beta-decay. Searches for particle electric dipole moments, such as that of the neutron, are highly sensitive to new physics beyond the Standard Model of particle physics, and may contribute to an understanding of the origin of the matter-antimatter asymmetry of the universe. A secondary thrust of our research program concerns the electromagnetic structure of the neutron. With intermediate- energy electrons, we will extend hadronic physics measurements of the (neutral) neutron's internal charge distribution to the smallest length scales ever probed. Such measurements are important for a comparison of data with predictions from theoretical formulations of the strong interaction concerning the nucleon's internal quark structure.