Evaluating VudV_{ud} from neutron beta decays

Although well studied, the neutron still offers a unique laboratory for precise tests of Standard Model (SM) predictions. Neutron decay is free of nuclear structure corrections present in nuclear beta decays, and, with a $10^8$ times larger branching ratio than the theoretically cleaner pion beta decay, it is more readily accessible to experimental study than the latter. Measurements at sufficient precision of the neutron lifetime, and of correlations in free neutron beta decay, offer several stringent tests of the SM, including the weak quark couplings (quark-lepton universality), and certain extensions beyond the standard $V-A$ weak interaction theory. This paper focuses on the long-running free neutron beta decay experimental program aimed at obtaining an independent determination of the Cabibbo-Kobayashi-Maskawa (CKM) mixing matrix element $V_{ud}$. We discuss the present state of precision achieved in this program and briefly review the currently active projects, as well as the expected near-term improvements in the field.Comment: 6 pages, 3 figures, 1 table, presented at the 9th International Workshop on the CKM Unitarity Triangle, 28 November - 3 December 2016, Tata Institute for Fundamental Research (TIFR), Mumbai, India; to appear in Proceeding of Science, PoS(CKM2016

Electric dipole moments and the search for new physics

Static electric dipole moments of nondegenerate systems probe mass scales for physics beyond the Standard Model well beyond those reached directly at high energy colliders. Discrimination between different physics models, however, requires complementary searches in atomic-molecular-and-optical, nuclear and particle physics. In this report, we discuss the current status and prospects in the near future for a compelling suite of such experiments, along with developments needed in the encompassing theoretical framework.Comment: Contribution to Snowmass 2021; updated with community edits and endorsement

Radiative decays of the Sigma(0)(1385) and Lambda(1520) hyperons

The electromagnetic decays of the Sig0(1385) and Lambda(1520) hyperons were studied in photon-induced reactions gamma p -> K+ Lambda(1116)gamma in the CLAS detector at the Thomas Jefferson National Accelerator Facility. We report the first observation of the radiative decay of the Sig0(1385) and a measurement of the Lambda(1520) radiative decay width. For the Sig0(1385) -> Lambda(1116)gamma transition, we measured a partial width of 479+/-120(stat)+81-100(sys) keV, larger than all of the existing model predictions. For the Lambda(1520) -> Lambda(1116)gamma transition, we obtained a partial width of 167+/-43(stat)+26-12(sys) keV