Speaker
Description
The appearance of hyperons in dense neutron-star matter strongly affects the corresponding equation of state. The onset density of hyperons depends on their single-particle potentials. In this talk, I report the single-particle potentials [1] of the $\Lambda$ and $\Sigma$ hyperons, calculated using up-to-date baryon–baryon interactions derived within chiral effective field theory up to next-to-next-to-leading order [2]. It is found that the $\Sigma$ single-particle potential is more attractive than that obtained with previous chiral forces at next-to-leading order, reflecting constraints from the $\Sigma N$ differential cross sections measured in the recent J-PARC E40 experiment. Our recent progress will also be presented.
[1] A. Jinno, J. Haidenbauer, and U.-G. Meißner, Phys. Rev. C 112, 065209 (2025).
[2] J. Haidenbauer, U.-G. Meißner, A. Nogga, and H. Le, Eur. Phys. J. A 59, 63 (2023).