Refined analysis of $\Omega^{-} \bar{\Omega}^{+}$ polarization in electron-positron annihilation process

Zhe Zhang; Jiao Jiao Song; Ya-jin Zhou

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arXiv · 2312.04363

Refined analysis of $\Omega^{-} \bar{\Omega}^{+}$ polarization in electron-positron annihilation process

Zhe Zhang·Jiao Jiao Song·Ya-jin Zhou

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Abstract

We investigate the production of spin-3/2 hyperon pairs, $\Omega^- \bar{\Omega}^+$, in electron-positron annihilation within the helicity amplitude formalism. A refined selection of helicity basis matrices is proposed to relate polarization expansion coefficients and spin density matrix elements and to illuminate their inherent physical interpretations and symmetrical properties. With a novel parametrization scheme of helicity amplitudes, we perform an analysis of polarization correlation coefficients for double-tag $\Omega^- \bar{\Omega}^+$ pairs. We present three sets of expressions to describe the decay of $\Omega^{-}$ hyperons, and further address the existing tension in the measurements of its decay parameters, particularly $\phi_{\Omega}$. The method and the framework developed in this paper can also be applied to studies of the production and decay mechanisms of other spin-3/2 particles.

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Zhe Zhang, Jiao Jiao Song, Ya-jin Zhou. 2023-12-07. Refined analysis of $\Omega^{-} \bar{\Omega}^{+}$ polarization in electron-positron annihilation process. https://arxiv.org/abs/2312.04363

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