Determination of the ${\Lambda }_c^{+}$ spin via the reaction $e^{+}{e}^{-}\to {\Lambda }_c^{+}{\bar{\Lambda }}_c^{-}$

Abstract

We report on a comparison of two possible ${\Lambda }_c^{+}$ spin hypotheses, $J=\frac{1}{2}$ and $\frac{3}{2}$, via the process $e^{+}{e}^{-}\to {\Lambda }_c^{+}{\bar{\Lambda }}_c^{-}$, using the angular distributions of ${\Lambda }_c^{+}$ decays into $p{K}_S^0$, $\Lambda {\pi }^{+}$, ${\Sigma }^0{\pi }^{+}$, and ${\Sigma }^{+}{\pi }^0$. The data were recorded at $\sqrt{s}=4.6$ GeV with the BESIII detector and correspond to an integrated luminosity of 587 pb${}^{-1}$. The ${\Lambda }_c^{+}$ spin is determined to be $J=\frac{1}{2}$, with this value favored over the $\frac{3}{2}$ hypothesis with a significance corresponding to more than 6 Gaussian standard deviations.

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Cited by in corpus (8)

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• Masses and radiative decay widths of S- and P-wave singly-, doubly- and triply-heavy charm and bottom baryons
• Production and decay of polarized hyperon-antihyperon pairs
• Molecular states of $D^{\ast }{D}^{\ast }{\bar{K}}^{\ast }$ nature
• 70 Years of Hyperon Spectroscopy: A review of strange $\Xi$, $\Omega$ baryons, and the spectrum of charmed and bottom baryons
• Topological amplitudes of charmed baryon decays in the $SU(3{)}_F$ limit
• The electromagnetic form factors and spin polarization of ${\Lambda }_c^{+}$ in the process $e^{+}{e}^{-}\to {\Lambda }_c^{+}{\bar{\Lambda }}_c^{-}$