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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:

${{\mathit \chi}_{{{b2}}}{(1P)}}$

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

Observed in radiative decay of the ${{\mathit \Upsilon}{(2S)}}$, therefore ${}^{C} = +$. Branching ratio requires E1 transition, M1 is strongly disfavored, therefore ${}^{P} = +$. $\mathit J = 2$ from SKWARNICKI 1987.

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${{\mathit \chi}_{{{b2}}}{(1P)}}$ MASS

$9912.21$ $\pm0.26$ $\pm0.31$ MeV

${\mathit m}_{{{\mathit \chi}_{{{b2}}}{(1P)}}}-{\mathit m}_{{{\mathit \chi}_{{{b1}}}{(1P)}}}$

$19.17$ $\pm0.20$ MeV

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

$110.44$ $\pm0.29$ MeV (S = 1.1)

▸ ${{\mathit \chi}_{{{b2}}}{(1P)}}$ Cross-Particle Branching Ratios

${{\mathit \chi}_{{{b2}}}{(1P)}}$ DECAY MODES

Mode

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

Scale Factor/
Conf. Level

P(MeV/c)

${{\mathit \gamma}}{{\mathit \Upsilon}{(1S)}}$

($18.0$ $\pm1.0$ ) $\%$

${{\mathit D}^{0}}{{\mathit X}}$

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

($8$ $\pm5$) $ \times 10^{-5}$

2 ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit K}^{-}}{{\mathit K}_S^0}$

$<1.0$ $\times 10^{-4}$

2 ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit K}^{-}}{{\mathit K}_S^0}$ 2 ${{\mathit \pi}^{0}}$

($5.3$ $\pm2.4$) $ \times 10^{-4}$

2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$2 ${{\mathit \pi}^{0}}$

($3.5$ $\pm1.4$) $ \times 10^{-4}$

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

($1.1$ $\pm0.4$) $ \times 10^{-4}$

2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}{{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{0}}$

($2.1$ $\pm0.9$) $ \times 10^{-4}$

2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}{{\mathit K}^{+}}{{\mathit K}^{-}}$2 ${{\mathit \pi}^{0}}$

($3.9$ $\pm1.8$) $ \times 10^{-4}$

3 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}{{\mathit K}^{-}}{{\mathit K}_S^0}$ ${{\mathit \pi}^{0}}$

$<5$ $\times 10^{-4}$

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

($7.0$ $\pm3.1$) $ \times 10^{-5}$

3 ${{\mathit \pi}^{+}}$3 ${{\mathit \pi}^{-}}$2 ${{\mathit \pi}^{0}}$

($1.0$ $\pm0.4$) $ \times 10^{-3}$

3 ${{\mathit \pi}^{+}}$3 ${{\mathit \pi}^{-}}{{\mathit K}^{+}}{{\mathit K}^{-}}$

$<8$ $\times 10^{-5}$

3 ${{\mathit \pi}^{+}}$3 ${{\mathit \pi}^{-}}{{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{0}}$

($3.6$ $\pm1.5$) $ \times 10^{-4}$

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

($8$ $\pm4$) $ \times 10^{-5}$

4 ${{\mathit \pi}^{+}}$4 ${{\mathit \pi}^{-}}$2 ${{\mathit \pi}^{0}}$

($1.8$ $\pm0.7$) $ \times 10^{-3}$

${{\mathit J / \psi}}{{\mathit J / \psi}}$

$<4$ $\times 10^{-5}$

${{\mathit J / \psi}}{{\mathit \psi}{(2S)}}$

$<5$ $\times 10^{-5}$

${{\mathit \psi}{(2S)}}{{\mathit \psi}{(2S)}}$

$<1.6$ $\times 10^{-5}$

${{\mathit J / \psi}{(1S)}}$ anything

($1.5$ $\pm0.4$) $ \times 10^{-3}$

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