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arXiv · 1905.01809

Production of a 4He_Lambda hypernucleus in the 4He(pi, K) reactions reexamined

Toru Harada·Yoshiharu Hirabayashi
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Abstract

We investigate theoretically production cross sections of the $J^\pi=$ 0$^+$ ground state of a $^4_\Lambda$He hypernucleus in the $^4$He($\pi$,~$K$) reaction with a distorted-wave impulse approximation using the optimal Fermi-averaged $\pi N\to K\Lambda$ $t$ matrix. We demonstrate the sensitivity of the production cross sections to the $\Lambda$ wavefunctions obtained from $3N$-$\Lambda$ potentials and to meson distorted waves in eikonal distortions. It is shown that the calculated laboratory cross sections of the 0$^+$ ground state in $^4_\Lambda$He amount to $d\sigma/d\Omega_{\rm lab} \simeq$ 11 $\mu$b/sr at $p_{\pi}=$ 1.05 GeV/$c$ in the $K$ forward direction because of an advantage of the use of the s-shell target nucleus such as $^4$He. The importance of the recoil effects and the energy dependence of the $\pi N\to K\Lambda$ cross sections is also discussed.

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Toru Harada, Yoshiharu Hirabayashi. 2019-05-06. Production of a 4He_Lambda hypernucleus in the 4He(pi, K) reactions reexamined. https://doi.org/10.1103/physrevc.100.024605

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