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${{\mathit \Lambda}}$ DECAY PARAMETERS

See the ``Note on Baryon Decay Parameters'' in the neutron Listings. Some early results have been omitted.

$\Delta \Phi $ = $\Phi _{E}$ $−$ $\Phi _{M}$ in ${{\mathit \Lambda}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \pi}^{-}}$, ${{\overline{\mathit \Lambda}}}$ $\rightarrow$ ${{\overline{\mathit p}}}{{\mathit \pi}^{+}}$

INSPIRE   JSON  (beta) PDGID:

S018A03

Relative phase between G$_{E}$ and G$_{M}$.

S018A03 VALUE (degrees) EVTS DOCUMENT ID TECN  COMMENT • • We do not use the following data for averages, fits, limits, etc. • • $42$ $\pm10$ $\pm2$ 1, 2 ABLIKIM 2025 BQ   BES3 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\overline{\mathit \Lambda}}}{{\mathit \Lambda}}$ at $\sqrt {s }$ = 2.396 GeV $87.7$ $\pm20.6$ $\pm1.7$ 2.2k 3 ABLIKIM 2025 CK   BES3 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\overline{\mathit \Lambda}}}{{\mathit \Lambda}}$ at $\sqrt {s }$ = 3.773 GeV $37$ $\pm12$ $\pm6$ 4 ABLIKIM 2019 BF   BES3 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\overline{\mathit \Lambda}}}{{\mathit \Lambda}}$ at $\sqrt {s }$ = 2.396 GeV 1  ABLIKIM 2025BQ provides values in a range of $\sqrt {s }$ energies of $2.396 - 2.90$ GeV. We quote their most precise value at 2.396 GeV. 2  Determined using asymmetry parameter value $\alpha $ = $0.754$. 3  Determined using asymmetry parameter value ${{\mathit \alpha}}$ = $0.7542$. 4  Determined using asymmetry parameter value ${{\mathit \alpha}}$ = $0.750$ $\pm0.010$.

References

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