pdgLive

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

INSPIRE JSON (beta) 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 .

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

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

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

$19.10 \pm0.25$ MeV (S = 1.1)

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

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

B( ${{\mathit \chi}_{{b2}}{(1P)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \Upsilon}{(1S)}}$ ) ${\times }$ B( ${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \chi}_{{b2}}{(1P)}}$ ) ${\times }$ B( ${{\mathit \Upsilon}{(1S)}}$ $\rightarrow$ ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ )

$(3.38 \pm0.16) \times 10^{-4}$

[B( ${{\mathit \chi}_{{b2}}{(1P)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \Upsilon}{(1S)}}$ ) ${\times }$ B( ${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \chi}_{{b2}}{(1P)}}$ )] $/$ [B( ${{\mathit \chi}_{{b1}}{(1P)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \Upsilon}{(1S)}}$ ) ${\times }$ B( ${{\mathit \Upsilon}{(2S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \chi}_{{b1}}{(1P)}}$ )]

$0.556 \pm0.016$

B( ${{\mathit \chi}_{{b2}}{(1P)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \Upsilon}{(1S)}}$ ) ${\times }$ B( ${{\mathit \Upsilon}{(3S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \chi}_{{b2}}{(1P)}}$ ) ${\times }$ B( ${{\mathit \Upsilon}{(1S)}}$ $\rightarrow$ ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ )

$(3.8 \pm0.5) \times 10^{-5}$

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

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

$(18.0\pm{1.0})\%$

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

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

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

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 ${{\mathit \pi}^{0}}$

$(5.3\pm{2.4})\times 10^{-4}$

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

$(3.5\pm{1.4})\times 10^{-4}$

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

$(1.1\pm{0.4})\times 10^{-4}$

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

$(2.1\pm{0.9})\times 10^{-4}$

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

$(3.9\pm{1.8})\times 10^{-4}$

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

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

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

$(7.0\pm{3.1})\times 10^{-5}$

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

$(1.0\pm{0.4})\times 10^{-3}$

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

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

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

$(3.6\pm{1.5})\times 10^{-4}$

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

$(8\pm{4})\times 10^{-5}$

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

$(1.8\pm{0.7})\times 10^{-3}$

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

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

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

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

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

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

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

$(1.5\pm{0.4})\times 10^{-3}$

FOOTNOTES

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