A search for atomic parity violation in muonic atoms using a high-intensity pulsed muon beam at J-PARC

An exotic atom consisting of a negative muon and a nucleus is a muonic atom. Atomic parity violation in muonic atoms provides a unique opportunity to determine the Weinberg angle and search for physics beyond the standard model at the low energy scale. We have proposed a new experiment to perform X-ray spectroscopy of muonic atoms using a high-intensity pulsed muon beam at J-PARC. A scintillator-based calorimeter and a lowdensity gaseous target were developed for the experiment. As a feasibility study, we measured the yield of muon atoms and searched for muonic atom’s metastability using low-density methane gas. An overview of the experiment and the test experiment results are presented.