${{\boldsymbol \Sigma}}$ 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

${{\boldsymbol \Sigma}{(1480)}}$ Bumps $I(J^P)$ = $1(?^{?})$

These are peaks seen in ${{\mathit \Lambda}}{{\mathit \pi}}$ and ${{\mathit \Sigma}}{{\mathit \pi}}$ spectra in the reaction ${{\mathit \pi}^{+}}$ ${{\mathit p}}$ $\rightarrow$ ( ${{\mathit Y}}{{\mathit \pi}}$ ) ${{\mathit K}^{+}}$ at 1.7 ${\mathrm {GeV/}}\mathit c$. Also, the ${{\mathit Y}}$ polarization oscillates in the same region. MILLER 1970 suggests a possible alternate explanation in terms of a reflection of ${{\mathit N}{(1675)}}$ $\rightarrow$ ${{\mathit \Lambda}}{{\mathit K}}$ decay. However, such an explanation for the ( ${{\mathit \Sigma}^{+}}{{\mathit \pi}^{0}}$ ) ${{\mathit K}^{+}}$ channel in terms of ${{\mathit \Delta}{(1650)}}$ $\rightarrow$ ${{\mathit \Sigma}}{{\mathit K}}$ decay seems unlikely (see PAN 1970 ). In addition such reflections would also have to account for the oscillation of the ${{\mathit Y}}$ polarization in the 1480 MeV region. HANSON 1971 , with less data than PAN 1970 , can neither confirm nor deny the existence of this state. MAST 1975 sees no structure in this region in ${{\mathit K}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \Lambda}}{{\mathit \pi}^{0}}$ . ENGELEN 1980 performs a multichannel analysis of ${{\mathit K}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\overline{\mathit K}}^{0}}{{\mathit \pi}^{-}}$ at 4.2 ${\mathrm {GeV/}}\mathit c$. They observe a 3.5 standard-deviation signal at 1480 MeV in ${{\mathit p}}{{\overline{\mathit K}}^{0}}$ which cannot be explained as a reflection of any competing channel. PRAKHOV 2004 sees no evidence for this or other light ${{\mathit \Sigma}}$ resonances, aside from the ${{\mathit \Sigma}{(1385)}}$, in ${{\mathit K}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \Lambda}}{{\mathit \pi}^{0}}{{\mathit \pi}^{0}}$ . ZYCHOR 2006 finds peaks in ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit K}^{+}}$ ( ${{\mathit \pi}^{\pm}}{{\mathit X}^{\mp}}$ ) at $\mathit p_{{\mathrm {beam}}}$ = 3.65$~$GeV/c.
${{\mathit \Sigma}{(1480)}}$ MASS (PRODUCTION EXPERIMENTS)   $\approx1480$ MeV 
${{\mathit \Sigma}{(1480)}}$ WIDTH (PRODUCTION EXPERIMENTS)
$\Gamma_{1}$ ${{\mathit N}}{{\overline{\mathit K}}}$ 178
$\Gamma_{2}$ ${{\mathit \Lambda}}{{\mathit \pi}}$ 296
$\Gamma_{3}$ ${{\mathit \Sigma}}{{\mathit \pi}}$ 232