Production of neutron-rich Λ-hypernuclei with (π−, K+) reaction through ∑-hypernuclear formation

Abstract

We have investigated theoretically the missing-mass spectral function of (π⁻, K⁺) reaction on ⁹Be target to populate ∑^−pLi ∑-hypernucleus. If there is an appreciable amount of ∑N-ΛN coupling effect, this double charge exchange reaction would be a plausible way to populate neutron-rich Λ-hypernuclei. We have used Plane Wave Impulse Approximation Method together with ∑-nucleus Woods-Saxon potential. It is found that the strengths of V_∑=−20 MeV and W_∑=-3MeV give an observable narrow peak in the spectrum of ∑⁻⁹Li. To investigate the Λ-L coupling effect and ∑ mixing component _Λ⁹He, we also studied the structure calculation of _Λ⁹He by solving the coupled channel Schrodinger equation. Λ-∑ coherent coupling effect is 0.19 MeV and ∑ mixing probability is 0.2% in _Λ⁹He.