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arXiv · 2305.09208

Production of nuclei and hypernuclei in pion-induced reactions near threshold energies

Apiwit Kittiratpattana·Tom Reichert·Nihal Buyukcizmeci·Alexander Botvina·Ayut Limphirat·Christoph Herold·Jan Steinheimer·Marcus Bleicher
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Abstract

The Ultra-relativistic Quantum Molecular Dynamics model is employed to simulate $\pi^-+\mathrm{C}$ and $\pi^-+\mathrm{W}$ collisions at p$_\mathrm{lab}=1.7$ GeV motivated by the recent HADES results. By comparing the proton and $\Lambda$ transverse momentum spectra, it was observed that the data and transport model calculation show a good agreement, if cluster formation is included to obtain the free proton spectra. Predictions of light cluster ($d$, $t$, $^3$He, $^4$He, as well as ${}^{3}_\Lambda$H and $\Xi$N) multiplicities and spectra are made using a coalescence mechanism. The resulting multiplicities suggest that the pion beam experiment can produce a substantial amount of ${}^{3}_\Lambda$H, especially in $\pi^-+\mathrm{W}$ collisions due to the stopping of the $\Lambda$ inside the large tungsten nucleus. The findings are supplemented by a statistical multi-fragmentation analysis suggesting that even larger hyper-fragments are produced copiously. It is suggested that even double strange hypernuclei are in reach and might be studied in more detail using a slightly higher pion beam momentum.

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Apiwit Kittiratpattana, Tom Reichert, Nihal Buyukcizmeci, Alexander Botvina, Ayut Limphirat, Christoph Herold, Jan Steinheimer, Marcus Bleicher. 2023-05-16. Production of nuclei and hypernuclei in pion-induced reactions near threshold energies. https://doi.org/10.1103/physrevc.109.044913

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