Study of hyperon-nucleon interactions at BESIII

Hyperon-nucleon interactions are important to understand quantum chromodynamics and so-called “hyperon puzzle” of neutron star, but limited by the availability and short-lifetime of hyperon beams, the progress of relevant research is very slow. A novel method is used to study hyperon-nucleon interactions based on hyperons produced in the decays of 10 billion $J\mathrm{/}\psi$ events collected with the BESIII detector at the BEPCII storage ring, and the target material is beam pipe. The reactions ${\mathrm{\Xi }}^{0}n\to {\mathrm{\Xi }}^{-}p$ and $\mathrm{\Lambda }N\to {\mathrm{\Sigma }}^{+}X$ have been observed and measured at BESIII. This is the first study of hyperon-nucleon interactions in electron-positron collisions and opens up a new direction for such research.