Commissioning of the Nab experiment*

The Nab experiment, currently taking data at the Spallation Neutron Source, uses an unpolarized neutron beam to precisely measure two of the free neutron beta decay correlation parameters to probe physics beyond the Standard Model. The electron-neutrino correlation coefficient, a, will give us access to investigate CKM unitarity, and the Fierz interference term, b, will enable us to put bounds on the existence of scalar and tensor currents in the weak interaction. The Nab experiment uses two highly-pixelated, large-area silicon detectors at either end of a 7 m tall magnetic spectrometer to measure the electron energy and the proton time of flight, which can be used to construct nearly the full phase space of neutron decay, and make determinations of a and b. This talk will report on the status of the Nab experiment. I will highlight key efforts that we made during the most recent long beam outage including detector studies and upgrades to the detector electronics. Finally, I will discuss the performance of the Nab experiment during the current beam cycle and our transition from commissioning to production data-taking.