Search for rare decays at BESIII

Abstract

Based on 10 billion 𝐽/𝜓 events accumulated by the BESIII detector, we show the searches for the rare process of 𝐽/𝜓 weak decays. We also search for other rare decay process, such as the FCNC process 𝐷 0 → 𝜋 0 𝜈 ν. Using 𝐽/𝜓 decay, BESIII also produce millions of Hyperon, which can be used to search for the rare decay process Ξ − → Ξ 0 𝑒𝜈.