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LIGHT UNFLAVORED MESONS
($\mathit S$ = $\mathit C$ = $\mathit B$ = 0)
For $\mathit I = 1$ (${{\mathit \pi}}$, ${{\mathit b}}$, ${{\mathit \rho}}$, ${{\mathit a}}$): ${\mathit {\mathit u}}$ ${\mathit {\overline{\mathit d}}}$, ( ${\mathit {\mathit u}}$ ${\mathit {\overline{\mathit u}}}−$ ${\mathit {\mathit d}}$ ${\mathit {\overline{\mathit d}}})/\sqrt {2 }$, ${\mathit {\mathit d}}$ ${\mathit {\overline{\mathit u}}}$;
for $\mathit I = 0$ (${{\mathit \eta}}$, ${{\mathit \eta}^{\,'}}$, ${{\mathit h}}$, ${{\mathit h}^{\,'}}$, ${{\mathit \omega}}$, ${{\mathit \phi}}$, ${{\mathit f}}$, ${{\mathit f}^{\,'}}$): ${\mathit {\mathit c}}_{{\mathrm {1}}}$( ${{\mathit u}}{{\overline{\mathit u}}}$ $+$ ${{\mathit d}}{{\overline{\mathit d}}}$ ) $+$ ${\mathit {\mathit c}}_{{\mathrm {2}}}$( ${{\mathit s}}{{\overline{\mathit s}}}$ )

INSPIRE JSON (beta) PDGID:

${{\mathit f}_{{2}}{(1270)}}$

$I^G(J^{PC})$ = $0^+(2^{+ +})$

${{\mathit f}_{{2}}{(1270)}}$ T-MATRIX POLE $\sqrt {\mathit s }$

$(1260 - 1283) − {\mit i} (90 - 110)$ MeV

${{\mathit f}_{{2}}{(1270)}}$ MASS

$1275.4 \pm0.8$ MeV (S = 1.1)

${{\mathit f}_{{2}}{(1270)}}$ WIDTH

$186.6 \pm2.3$ MeV (S = 1.5)

Helicity-0/Helicity-2 RATIO IN ${{\mathit \gamma}}$ ${{\mathit \gamma}}$ $\rightarrow$ ${{\mathit f}_{{2}}{(1270)}}$ $\rightarrow$ ${{\mathit \pi}}{{\mathit \pi}}$

$0.037 {}^{+0.160}_{-0.029}$

${{\mathit f}_{{2}}{(1270)}}$ DECAY MODES

${{\mathit \pi}}{{\mathit \pi}}$

$(84.3^{+2.9}_{-0.9})\%$

${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$2 ${{\mathit \pi}^{0}}$

$(7.7^{+1.1}_{-3.2})\%$

${{\mathit K}}{{\overline{\mathit K}}}$

$(4.6\pm{0.4})\%$

2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$

$(2.8\pm{0.4})\%$

${{\mathit \eta}}{{\mathit \eta}}$

$(4.0\pm{0.8})\times 10^{-3}$

4 ${{\mathit \pi}^{0}}$

$(3.0\pm{1.0})\times 10^{-3}$

${{\mathit \gamma}}{{\mathit \gamma}}$

$(1.42\pm{0.24})\times 10^{-5}$

${{\mathit \eta}}{{\mathit \pi}}{{\mathit \pi}}$

$<8\times 10^{-3}$

${{\mathit K}^{0}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}$ + c.c.

$<3.4\times 10^{-3}$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

$<6\times 10^{-10}$

FOOTNOTES

Constrained Fit information

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