${{\mathit \Sigma}^{+}}$ DECAY PARAMETERS

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

$\alpha _{0}$ FOR ${{\mathit \Sigma}^{+}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \pi}^{0}}$

INSPIRE   PDGID:
S019A0
VALUE EVTS DOCUMENT ID TECN  COMMENT
$\bf{ -0.982 \pm0.014}$ OUR FIT
$\bf{ -0.982 {}^{+0.016}_{-0.013}}$ OUR AVERAGE
$-0.998$ $\pm0.037$ $\pm0.009$ 93k 1
ABLIKIM
2020X
 BES3 ${{\mathit J / \psi}}$ $/$ ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit \Sigma}^{+}}{{\overline{\mathit \Sigma}}^{-}}$
$-0.945$ ${}^{+0.055}_{-0.042}$ 1259 2
LIPMAN
1973
OSPK ${{\mathit \pi}^{+}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \Sigma}^{+}}$
$-0.940$ $\pm0.045$ 16k
BELLAMY
1972
ASPK ${{\mathit \pi}^{+}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \Sigma}^{+}}{{\mathit K}^{+}}$
$-0.98$ ${}^{+0.05}_{-0.02}$ 1335 3
HARRIS
1970
OSPK ${{\mathit \pi}^{+}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \Sigma}^{+}}{{\mathit K}^{+}}$
$-0.999$ $\pm0.022$ 32k
BANGERTER
1969
HBC ${{\mathit K}^{-}}{{\mathit p}}$ 0.4 ${\mathrm {GeV/}}\mathit c$
1  ABLIKIM 2020X uses production through ${{\mathit e}^{+}}$ ${{\mathit e}}$ $\rightarrow$ ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \Sigma}^{+}}{{\overline{\mathit \Sigma}}^{-}}$ and ${{\mathit e}^{+}}$ ${{\mathit e}}$ $\rightarrow$ ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit \Sigma}^{+}}{{\overline{\mathit \Sigma}}^{-}}$, with 87,815 and 5,327 events, respectively. Note that the reported values of decay parameters ${{\mathit \alpha}_{{{0}}}}$ of ${{\mathit \Sigma}^{+}}$ and ${{\overline{\mathit \alpha}}_{{{0}}}}$ of ${{\overline{\mathit \Sigma}}^{-}}$ are correlated.
2  Decay protons scattered off aluminum.
3  Decay protons scattered off carbon.
References