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BOTTOM BARYONS ($\mathit B$ = $-1$) ${{\mathit \Lambda}_{{{b}}}^{0}}$ = ${{\mathit u}}{{\mathit d}}{{\mathit b}}$, ${{\mathit \Sigma}_{{{b}}}^{0}}$ = ${{\mathit u}}{{\mathit d}}{{\mathit b}}$, ${{\mathit \Sigma}_{{{b}}}^{+}}$ = ${{\mathit u}}{{\mathit u}}{{\mathit b}}$, ${{\mathit \Sigma}_{{{b}}}^{-}}$ = ${{\mathit d}}{{\mathit d}}{{\mathit b}}$ ${{\mathit \Xi}_{{{b}}}^{0}}$ = ${{\mathit u}}{{\mathit s}}{{\mathit b}}$, ${{\mathit \Xi}_{{{b}}}^{-}}$ = ${{\mathit d}}{{\mathit s}}{{\mathit b}}$, ${{\mathit \Omega}_{{{b}}}^{-}}$ = ${{\mathit s}}{{\mathit s}}{{\mathit b}}$

INSPIRE   JSON PDGID: S069

${{\mathit \Xi}_{{{b}}}^{-}}$ $I(J^P)$ = $1/2(1/2^{+})$ I, J, P need confirmation.

In the quark model, ${{\mathit \Xi}_{{{b}}}^{0}}$ and ${{\mathit \Xi}_{{{b}}}^{-}}$ are an isodoublet ($\mathit usb$, $\mathit dsb$) state; the lowest ${{\mathit \Xi}_{{{b}}}^{0}}$ and ${{\mathit \Xi}_{{{b}}}^{-}}$ ought to have $\mathit J{}^{P} = 1/2{}^{+}$. None of $\mathit I$, $\mathit J$, or ${}^{P}$ have actually been measured.

${{\mathit \Xi}_{{{b}}}^{-}}$ MASS

${{\mathit \Xi}_{{{b}}}^{-}}$ MASS   $5797.0 \pm0.6$ MeV (S = 1.7)

${\mathit m}_{{{\mathit \Xi}_{{{b}}}^{-}}}–{\mathit m}_{{{\mathit \Lambda}_{{{b}}}^{0}}}$   $177.46 \pm0.31$ MeV (S = 1.3)

${\mathit m}_{{{\mathit \Xi}_{{{b}}}^{-}}}–{\mathit m}_{{{\mathit \Xi}_{{{b}}}^{0}}}$   $5.9 \pm0.6$ MeV

${{\mathit \Xi}_{{{b}}}^{-}}$ MEAN LIFE

${{\mathit \Xi}_{{{b}}}^{-}}$ MEAN LIFE   $(1.572 \pm0.040) \times 10^{-12}$ s

MEAN LIFE RATIOS

${\mathit \tau}_{{{\mathit \Xi}_{{{b}}}^{-}}}$ $/$ ${\mathit \tau}_{{{\mathit \Lambda}_{{{b}}}^{0}}}$ mean life ratio   $1.089 \pm0.028$

${\mathit \tau}_{{{\mathit \Xi}_{{{b}}}^{-}}}$ $/$ ${\mathit \tau}_{{{\mathit \Xi}_{{{b}}}^{0}}}$ mean life ratio   $1.08 \pm0.04$

$\mathit P$ VIOLATION ASYMMETRY

$\mathit A_{P}({{\mathit \Xi}_{{{b}}}}$), ${{\mathit \Xi}_{{{b}}}^{-}}$ $−$ ${{\mathit \Xi}_{{{b}}}^{+}}$ production asymmetry   $-0.02 \pm0.04$

CP VIOLATION in ${{\mathit \Xi}_{{{b}}}}$ deays

$\mathit A_{CP}$( ${{\mathit \Xi}_{{{b}}}^{-}}$ $\rightarrow$ ${{\mathit \Sigma}{(1385)}}{{\mathit K}^{-}}$)   $-0.3 \pm0.8$

$\mathit A_{CP}$( ${{\mathit \Xi}_{{{b}}}^{-}}$ $\rightarrow$ ${{\mathit \Lambda}{(1405)}}{{\mathit K}^{-}}$)   $0.0 \pm0.4$

$\mathit A_{CP}$( ${{\mathit \Xi}_{{{b}}}^{-}}$ $\rightarrow$ ${{\mathit \Lambda}{(1520)}}{{\mathit K}^{-}}$)   $-0.05 \pm0.12$

$\mathit A_{CP}$( ${{\mathit \Xi}_{{{b}}}^{-}}$ $\rightarrow$ ${{\mathit \Lambda}{(1670)}}{{\mathit K}^{-}}$)   $0.03 \pm0.17$

$\mathit A_{CP}$( ${{\mathit \Xi}_{{{b}}}^{-}}$ $\rightarrow$ ${{\mathit \Sigma}{(1775)}}{{\mathit K}^{-}}$)   $-0.47 \pm0.30$

$\mathit A_{CP}$( ${{\mathit \Xi}_{{{b}}}^{-}}$ $\rightarrow$ ${{\mathit \Sigma}{(1915)}}{{\mathit K}^{-}}$)   $0.11 \pm0.34$

${{\mathit \Xi}_{{{b}}}^{-}}$ DECAY MODES
Mode   Fraction ($\Gamma_i$ / $\Gamma$) Scale Factor/ Conf. Level P(MeV/c)   $\Gamma_{1}$ ${{\mathit J / \psi}}{{\mathit \Xi}^{-}}$ ${\times }$ B( ${{\mathit b}}$ $\rightarrow$ ${{\mathit \Xi}_{{{b}}}^{-}}$)   $(1.02^{+0.26}_{-0.21})\times 10^{-5}$ 1782   $\Gamma_{2}$ ${{\mathit J / \psi}}{{\mathit \Lambda}}{{\mathit K}^{-}}$ ${\times }$ B( ${{\mathit b}}$ $\rightarrow$ ${{\mathit \Xi}_{{{b}}}^{-}}$)   $(2.5\pm{0.4})\times 10^{-6}$ 1631   $\Gamma_{3}$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit K}^{-}}$ ${\times }$ B( ${{\mathit b}}$ $\rightarrow$ ${{\mathit \Xi}_{{{b}}}^{-}}$)   $(3.7\pm{0.8})\times 10^{-8}$ 2731   $\Gamma_{4}$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit K}^{-}}$   seen 2731   $\Gamma_{5}$ ${{\mathit p}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$   2813   $\Gamma_{6}$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit \pi}^{-}}$   seen 2783   $\Gamma_{7}$ ${{\mathit \Lambda}_{{{b}}}^{0}}{{\mathit \pi}^{-}}$ ${\times }$ B( ${{\mathit b}}$ $\rightarrow$ ${{\mathit \Xi}_{{{b}}}^{-}})/B({{\mathit b}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{b}}}^{0}}$ )   $(7.0\pm{0.9})\times 10^{-4}$ 99   $\Gamma_{8}$ ${{\mathit \Xi}_{{{c}}}^{0}}{{\mathit \pi}^{-}}$   seen 2367   $\Gamma_{9}$ ${{\mathit \Sigma}{(1385)}}{{\mathit K}^{-}}$   $(2.6\pm{2.3})\times 10^{-7}$ 2707   $\Gamma_{10}$ ${{\mathit \Lambda}{(1405)}}{{\mathit K}^{-}}$   $(1.9\pm{1.2})\times 10^{-7}$ 2702   $\Gamma_{11}$ ${{\mathit \Lambda}{(1520)}}{{\mathit K}^{-}}$   $(7.6\pm{3.2})\times 10^{-7}$ 2673   $\Gamma_{12}$ ${{\mathit \Lambda}{(1670)}}{{\mathit K}^{-}}$   $(4.5\pm{2.3})\times 10^{-7}$ 2629   $\Gamma_{13}$ ${{\mathit \Sigma}{(1775)}}{{\mathit K}^{-}}$   $(2.2\pm{1.5})\times 10^{-7}$ 2599   $\Gamma_{14}$ ${{\mathit \Sigma}{(1915)}}{{\mathit K}^{-}}$   $(2.6\pm{2.5})\times 10^{-7}$ 2553   $\Gamma_{15}$ ${{\mathit \Xi}^{-}}{{\mathit \gamma}}$   $<1.3\times 10^{-4}$ CL=95%
FOOTNOTES