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arXiv · 2106.04256

Production cross sections of $^{3,4}_Λ$H bound states in $^{3,4}$He($K^-$, $π^0$) reactions at 1 GeV/$c$

Toru Harada·Yoshiharu Hirabayashi
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Abstract

We investigate theoretically productions of $^{3,4}_Λ$H bound states in the exothermic ($K^-$, $π^0$) reactions on $^{3,4}$He targets at $p_{K^-}=$ 1.0 GeV/c in a distorted-wave impulse approximation with the optimal Fermi-averaging $K^-p\toπ^0Λ$ $t$ matrix. We calculate angular distributions of the laboratory differential cross sections $dσ/dΩ_{\rm lab}$ and the integrated cross sections $σ_{\rm lab}$ for a $J^P= 0^+$ ground state and a $J^P=1^+$ excited state of $^4_Λ$H at $π^0$ forward-direction angles of $θ_{\rm lab}=$ 0$^\circ$-20$^\circ$, and those for a $J^P= 1/2^+$ ground state of $^3_Λ$H. The production of a $J^P=3/2^+$ excited state of $^3_Λ$H as a virtual state is also evaluated. The comparison in $dσ/dΩ_{\rm lab}$ and $σ_{\rm lab}$ between $^4_Λ$H and $^3_Λ$H provides examining the mechanism of the production and structure of $^{3,4}_Λ$H, as well as in the endothermic ($π^-$, $K^0$) reactions at $p_{π^-}=$ 1.05 GeV/c. This investigation confirms the feasibility of lifetime measurements of $^3_Λ$H at the J-PARC experiments.

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Toru Harada, Yoshiharu Hirabayashi. 2021-08-17. Production cross sections of $^{3,4}_Λ$H bound states in $^{3,4}$He($K^-$, $π^0$) reactions at 1 GeV/$c$. https://doi.org/10.1016/j.nuclphysa.2021.122301

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