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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:

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

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

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)

3 ${{\mathit h}^{+}}$3 ${{\mathit h}^{-}}$

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

4 ${{\mathit h}^{+}}$4 ${{\mathit h}^{-}}$

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

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

$<9$ $\times 10^{-3}$

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

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