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${\mathit {\mathit b}}$ ${\mathit {\overline{\mathit b}}}$ MESONS (including possibly non-${\mathit {\mathit q}}$ ${\mathit {\overline{\mathit q}}}$ states)

INSPIRE   JSON PDGID: M171

${{\mathit \eta}_{{{b}}}{(1S)}}$ $I^G(J^{PC})$ = $0^+(0^{- +})$

Quantum numbers shown are quark-model predictions. Observed in radiative decay of the ${{\mathit \Upsilon}{(3S)}}$, therefore ${}^{C} = +$.

${{\mathit \eta}_{{{b}}}{(1S)}}$ MASS $9398.7$ $\pm2.0$ MeV (S = 1.5)

${\mathit m}_{{{\mathit \Upsilon}{(1S)}}}-{\mathit m}_{{{\mathit \eta}_{{{b}}}}}$ $62.3$ $\pm3.2$ MeV (S = 1.8)

${{\mathit \gamma}}$ ENERGY IN ${{\mathit \Upsilon}{(3S)}}$ DECAY $920.6^{+2.8}_{-3.2}$ MeV

${{\mathit \gamma}}$ ENERGY IN ${{\mathit \Upsilon}{(2S)}}$ DECAY $609$ $\pm5$ MeV

${{\mathit \eta}_{{{b}}}{(1S)}}$ WIDTH $10^{+5}_{-4}$ MeV

${{\mathit \eta}_{{{b}}}{(1S)}}$ DECAY MODES

Mode   Fraction ($\Gamma_i$ / $\Gamma$) Scale Factor/ Conf. Level P(MeV/c)   $\Gamma_{1}$ hadrons seen     $\Gamma_{2}$ 3 ${{\mathit h}^{+}}$3 ${{\mathit h}^{-}}$ not seen 4672   $\Gamma_{3}$ 2 ${{\mathit h}^{+}}$2 ${{\mathit h}^{-}}$ not seen 4689   $\Gamma_{4}$ 4 ${{\mathit h}^{+}}$4 ${{\mathit h}^{-}}$ not seen 4648   $\Gamma_{5}$ ${{\mathit \gamma}}{{\mathit \gamma}}$ not seen 4699   $\Gamma_{6}$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ $<9$ $\times 10^{-3}$ CL=90% 4698   $\Gamma_{7}$ ${{\mathit \tau}^{+}}{{\mathit \tau}^{-}}$ <8 $\%$ CL=90% 4350