In this talk I will present a theoretical perspective on low-energy searches for physics beyond the Standard Model. After an overview of the field of precision measurements and the search for rare processes, I will focus on two examples that illustrate the breadth of the field: precision studies of beta decays and the search for permanent electric dipole moments.
Next-generation experiments are poised to explore lepton-number violation, discern the neutrino mass hierarchy, understand the particle nature of dark matter, and answer other fundamental questions aimed at testing the validity and extent of the Standard Model. Nuclei are used for these high-precision tests of the Standard Model and for searches of physics Beyond the Standard Model. Without a...
State-of-the-art direct neutrino mass searches have recently achieved sensitivity below 1 eV. The KATRIN experiment will run through 2025 projecting sensitivity to reach down to $m_\beta$ of 200 meV. But KATRIN’s MAC-E filter technology and molecular tritium source are reaching their limitations in this experimental phase. Sensitivity to cover the inverted neutrino mass ordering and beyond...
Precision studies of beta decay can provide stringent tests of the standard model, and probes for new physics, at a level that is competitive with constraints from high energy particle colliders. Recent evaluations of the “inner radiative correction” have led to a 3-sigma departure from unitarity in the first row of the CKM matrix. Neutron beta decay is an ideal system for making...
The extreme electromagnetic environments present in polar molecules make them highly sensitive to fundamental symmetry violations, both within and beyond the standard model. In this talk I will review the current status of the field, discuss ongoing developments, and provide an outlook for the future.
Experimental tests of fundamental symmetries using nuclei and other particles subject to the strong nuclear force have led to the discovery of parity (P) violation and the discovery of charge-parity (CP) violation. It is believed that additional sources of CP-violation may be needed to explain the apparent scarcity of antimatter in the observable universe. A particularly sensitive and...
Despite being electrically neutral, the neutron can exhibit an electric dipole moment if its center of charge offsets from its center of mass. The resulting static electric dipole moment (EDM) probes new CP-violating physics at energy scales well beyond those reached directly at high-energy colliders. The latest experimental limit on the nEDM, reported by the PSI group, is (0.0 ± 1.1stat ±...
The technique of parity-violating electron scattering (PVES) can be used to make relatively clean measurements of nuclear and nucleon properties. Electrons have long been used as clean nuclear probes because they do not interact via the strong force. Much of what we know about nuclei, nucleons and their constituents is from electromagnetic scattering. The parity-violating asymmetry in the...
As we mark the passage of 75 years since the discovery of the pi meson, the role that the pion plays in the strong interaction remains clear and central. The pi meson also presents a rich subject of study when it comes to weak interaction processes, in particular exploring the limits of the validity of the Standard Model, and searches for its possible extensions. Thanks to few and simple...
Neutrons have a long history at the forefront of precision metrology, from the first experiment demonstrating the effect of gravity on a quantum particle (the C.O.W. experiment), to demonstrations of the spinor’s 4\pi -periodicity, on to recent searches for chameleon dark energy fields. Compared to photons, electrons, and other wave-particle probes, neutrons offer a unique penetrating ability....
