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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 PDGID:

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

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

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

$(1260 - 1283) - i (90 - 110)$ MeV

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

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

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

$185.8^{+2.8}_{-2.1}$ MeV (S = 1.6)

▸ ${{\mathit f}_{{{2}}}{(1270)}}$ $\Gamma\mathrm {(i)}{}\Gamma\mathrm {({{\mathit \gamma}} {{\mathit \gamma}})}/\Gamma\mathrm {(total)}$

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

Mode

Fraction ($\Gamma_i$ / $\Gamma$)

Scale Factor/
Conf. Level

P(MeV/c)

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

($84.3^{+2.8}_{-1.0}$ ) $\%$

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

($7.7^{+1.2}_{-3.1}$ ) $\%$

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

($4.6$ $\pm0.4$ ) $\%$

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

($2.8$ $\pm0.4$ ) $\%$

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

($4.0$ $\pm0.8$) $ \times 10^{-3}$

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

($3.0$ $\pm1.0$) $ \times 10^{-3}$

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

($1.42$ $\pm0.24$) $ \times 10^{-5}$

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

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

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

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

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

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

Constrained Fit information

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