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:

${{\mathit f}_{{{2}}}^{\,'}{(1525)}}$

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

${{\mathit f}_{{{2}}}^{\,'}{(1525)}}$ MASS ^[1]

$1517.3$ $\pm2.4$ MeV (S = 2.8)

PRODUCED BY PION BEAM

PRODUCED BY ${{\mathit K}^{\pm}}$ BEAM

$1518.0$ $\pm2.7$ MeV (S = 2.9)

PRODUCED IN ${{\mathit e}^{+}}{{\mathit e}^{-}}$ ANNIHILATION AND PARTICLE DECAYS

$1514$ $\pm4$ MeV (S = 3.6)

PRODUCED IN ${{\overline{\mathit p}}}{{\mathit p}}$ ANNIHILATION

$1512$ $\pm4$ MeV

CENTRAL PRODUCTION

$1515$ $\pm15$ MeV

PRODUCED IN ${{\mathit e}}{{\mathit p}}$ COLLISIONS

$1512$ $\pm3.2$ MeV

${{\mathit f}_{{{2}}}^{\,'}{(1525)}}$ WIDTH ^[1]

$72^{+7}_{-6}$ MeV

PRODUCED BY PION BEAM

PRODUCED BY ${{\mathit K}^{\pm}}$ BEAM

$82$ $\pm6$ MeV

PRODUCED IN ${{\mathit e}^{+}}{{\mathit e}^{-}}$ ANNIHILATION AND PARTICLE DECAYS

$86$ $\pm4$ MeV (S = 2.4)

PRODUCED IN ${{\overline{\mathit p}}}{{\mathit p}}$ ANNIHILATION

$77$ $\pm5$ MeV

CENTRAL PRODUCTION

$70$ $\pm25$ MeV

PRODUCED IN ${{\mathit e}}{{\mathit p}}$ COLLISIONS

$83$ $\pm10$ MeV

${{\mathit f}_{{{2}}}^{\,'}{(1525)}}$ DECAY MODES

Mode

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

Scale Factor/
Conf. Level

P(MeV/c)

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

($88.8$ $\pm2.2$ ) $\%$

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

($10.3$ $\pm2.2$ ) $\%$

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

($8.2$ $\pm1.5$) $ \times 10^{-3}$

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

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

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

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

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

($1.12$ $\pm0.15$) $ \times 10^{-6}$

[1]	Our estimate. See the Particle Listings for details.

Constrained Fit information

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