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arXiv · 2409.04886

Partial-wave analysis to determine the spin of $\Xi(1690)^-$ and $\Xi(1820)^-$ produced in $\overline{p}p$ annihilation

Deepak Pachattu
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Abstract

Recently [arXiv:2201.03852v2] the PANDA collaboration studied the feasibility of determining the spin and parity of the $\Xi(1690)^{-}$and $\Xi(1820)^{-}$ resonances in the $\Lambda K^-$ system produced in $\bar{p}p$ collisions via the reaction channel $\overline{p} p \rightarrow \bar{\Xi}^{+} \Lambda K^{-}$. This contribution aims to study these reactions using a model-independent irreducible tensor formalism developed earlier. This study leads us to identify the partial-wave amplitude, which would be zero if $\Xi(1690)^{-}$ or $\Xi(1820)^{-}$ had spin-1/2, provided these resonances are produced at threshold (s-wave production).

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Deepak Pachattu. 2024-09-07. Partial-wave analysis to determine the spin of $\Xi(1690)^-$ and $\Xi(1820)^-$ produced in $\overline{p}p$ annihilation. https://arxiv.org/abs/2409.04886

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