Speaker
Description
The primary goal of the PNab experiment is to provide a high precision value for the axial coupling constant, gA, in neutron decay through measurement of angular correlations in the decay of polarized neutrons. The precision goal for the axial coupling constant is roughly the 0.02% for PNab, about a factor of two more precise than the highest precision measurements to date. A measurement at this precision will provide a new standard for the axial coupling constant and should set the stage for improved tests of CKM unitarity involving up quarks. The PNab experiment is conceived as a follow-up for the Nab experiment, currently taking data at the Spallation Neutron Source sited at Oak Ridge National Laboratory. PNab will utilize the same spectrometer and detector systems as Nab, permitting a leveraging of the extensive, high precision characterization of these systems for the Nab experiment. For PNab, the use of polarized neutrons provides an important tool to control and suppress some sources of systematic uncertainty. A more complete summary of the science goals and the possible schedule for this proposed experiment will be presented, focusing on the advantages of measuring spin-polarized samples.
