Search for Majoron at the COMET experiment

A new Goldstone particle named Majoron is introduced in order to explain the origin of neutrino mass via some new physics models assuming that neutrinos are Majorana particles.By expanding the signal region and using likelihood analysis,it becomes possible to search for Majoron using experiments originally designed to search forμ-e conversion.For the COMET experiment,the sensitivity of processμ→eJ is able to reach B(μ→eJ)=2.3×10-5in Phase-I and O(10-8)in Phase-II.Meanwhile,the sensitivities to search for Majoron in future experiments are also discussed in this article.