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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: M005

${{\mathit f}_{{{2}}}{(1270)}}$ $I^G(J^{PC})$ = $0^+(2^{+ +})$

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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)

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

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

Mode   Fraction ($\Gamma_i$ / $\Gamma$) Scale Factor/ Conf. Level P(MeV/c)   $\Gamma_{1}$ ${{\mathit \pi}}{{\mathit \pi}}$ ($84.3^{+2.8}_{-1.0}$ ) $\%$ S=1.2  623   $\Gamma_{2}$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$2 ${{\mathit \pi}^{0}}$ ($7.7^{+1.2}_{-3.1}$ ) $\%$ S=1.2  563   $\Gamma_{3}$ ${{\mathit K}}{{\overline{\mathit K}}}$ ($4.6$ $\pm0.4$ ) $\%$ S=2.7  404   $\Gamma_{4}$ 2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$ ($2.8$ $\pm0.4$ ) $\%$ S=1.2  559   $\Gamma_{5}$ ${{\mathit \eta}}{{\mathit \eta}}$ ($4.0$ $\pm0.8$) $ \times 10^{-3}$ S=2.1  326   $\Gamma_{6}$ 4 ${{\mathit \pi}^{0}}$ ($3.0$ $\pm1.0$) $ \times 10^{-3}$ 565   $\Gamma_{7}$ ${{\mathit \gamma}}{{\mathit \gamma}}$ ($1.42$ $\pm0.24$) $ \times 10^{-5}$ S=1.4  638   $\Gamma_{8}$ ${{\mathit \eta}}{{\mathit \pi}}{{\mathit \pi}}$ $<8$ $\times 10^{-3}$ CL=95% 478   $\Gamma_{9}$ ${{\mathit K}^{0}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}$ + c.c. $<3.4$ $\times 10^{-3}$ CL=95% 293   $\Gamma_{10}$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ $<6$ $\times 10^{-10}$ CL=90% 638

Constrained Fit information