${{\boldsymbol \Sigma}}$ BARYONS
($\boldsymbol S$ = $-1$, $\boldsymbol I$ = 1)
${{\mathit \Sigma}^{+}}$ = ${\mathit {\mathit u}}$ ${\mathit {\mathit u}}$ ${\mathit {\mathit s}}$, ${{\mathit \Sigma}^{0}}$ = ${\mathit {\mathit u}}$ ${\mathit {\mathit d}}$ ${\mathit {\mathit s}}$, ${{\mathit \Sigma}^{-}}$ = ${\mathit {\mathit d}}$ ${\mathit {\mathit d}}$ ${\mathit {\mathit s}}$

INSPIRE search

${{\boldsymbol \Sigma}{(1620)}}$ $I(J^P)$ = $1(1/2^{-})$

The ${\mathit S}_{\mathrm 11}$ state at 1697 MeV reported by VANHORN 1975 is tentatively listed under the ${{\mathit \Sigma}{(1750)}}$. CARROLL 1976 sees two bumps in the isospin-$1{}^{}{}^{}$ total cross section near this mass. GAO 2012 sees no evidence for this resonance. Production experiments are listed separately in the next entry.

${{\boldsymbol \Sigma}{(1620)}}$ POLE POSITION

REAL PART

$1680 \pm8$ MeV

$-2{\times }$IMAGINARY PART

$39 \pm11$ MeV

${{\boldsymbol \Sigma}{(1620)}}$ POLE RESIDUE

Normalized residue in ${{\mathit N}}$ ${{\overline{\mathit K}}}$ $\rightarrow$ ${{\mathit \Sigma}{(1620)}}$ $\rightarrow$ ${{\mathit \Sigma}}{{\mathit \pi}}$

$0.14 \pm0.03$

Normalized residue in ${{\mathit N}}$ ${{\overline{\mathit K}}}$ $\rightarrow$ ${{\mathit \Sigma}{(1620)}}$ $\rightarrow$ ${{\mathit \Lambda}}{{\mathit \pi}}$

$0.10 \pm0.03$

Normalized residue in ${{\mathit N}}$ ${{\overline{\mathit K}}}$ $\rightarrow$ ${{\mathit \Sigma}{(1620)}}$ $\rightarrow$ ${{\mathit \Xi}}{{\mathit K}}$

$0.02 \pm0.01$