pdgLive

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:

${{\mathit f}_{{{1}}}{(1285)}}$

$I^G(J^{PC})$ = $0^+(1^{+ +})$

${{\mathit f}_{{{1}}}{(1285)}}$ MASS

$1281.8$ $\pm0.5$ MeV (S = 1.7)

${{\mathit f}_{{{1}}}{(1285)}}$ WIDTH

$23.0$ $\pm1.1$ MeV (S = 1.6)

${{\mathit f}_{{{1}}}{(1285)}}$ DECAY MODES

Mode

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

Scale Factor/
Conf. Level

P(MeV/c)

4 ${{\mathit \pi}}$

($32.7$ $\pm1.8$ ) $\%$

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

($21.8$ $\pm1.2$ ) $\%$

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

($10.9$ $\pm0.6$ ) $\%$

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

($10.9$ $\pm0.6$ ) $\%$

${{\mathit \rho}^{0}}{{\mathit \rho}^{0}}$

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

$<7$ $\times 10^{-4}$

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

($35$ $\pm15$ ) $\%$

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

($52.2$ $\pm1.9$ ) $\%$

${{\mathit a}_{{{0}}}{(980)}}{{\mathit \pi}}$ [ignoring ${{\mathit a}_{{{0}}}{(980)}}$ $\rightarrow$ ${{\mathit K}}{{\overline{\mathit K}}}$ ]

($38$ $\pm4$ ) $\%$

${{\mathit \eta}}{{\mathit \pi}}{{\mathit \pi}}$ [excluding ${{\mathit a}_{{{0}}}{(980)}}{{\mathit \pi}}$ ]

($14$ $\pm4$ ) $\%$

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

($9.0$ $\pm0.4$ ) $\%$

${{\mathit K}}{{\overline{\mathit K}}^{*}{(892)}}$

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

($3.0$ $\pm0.9$) $ \times 10^{-3}$

${{\mathit \rho}^{\pm}}{{\mathit \pi}^{\mp}}$

$<3.1$ $\times 10^{-3}$

${{\mathit \gamma}}{{\mathit \rho}^{0}}$

($6.1$ $\pm1.0$ ) $\%$

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

($7.4$ $\pm2.6$) $ \times 10^{-4}$

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

$<9.4$ $\times 10^{-9}$

${{\mathit \gamma}}{{\mathit \gamma}^{*}}$

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

Constrained Fit information

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