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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:

${{\mathit \Lambda}_{{{b}}}^{0}}$

$I(J^P)$ = $0(1/2^{+})$

In the quark model, a ${{\mathit \Lambda}_{{{b}}}^{0}}$ is an isospin-0 ${{\mathit u}}{{\mathit d}}{{\mathit b}}$ state. The lowest ${{\mathit \Lambda}_{{{b}}}^{0}}$ ought to have $\mathit J{}^{P} = 1/2{}^{+}$. None of $\mathit I$, $\mathit J$, or $\mathit P$ have actually been measured.

Expand/Collapse All

▸ ${{\mathit \Lambda}_{{{b}}}^{0}}$ MASS

${{\mathit \Lambda}_{{{b}}}^{0}}$ MEAN LIFE

($1.468$ $\pm0.009$) $ \times 10^{-12}$ s

${\mathit \tau}_{{{\mathit \Lambda}_{{{b}}}^{0}}}/{\mathit \tau}_{{{\overline{\mathit \Lambda}}_{{{b}}}^{0}}}$

$0.94$ $\pm0.04$

▸ ${\mathit \tau}_{{{\mathit \Lambda}_{{{b}}}^{0}}}/{\mathit \tau}_{{{\mathit B}^{0}}}$ MEAN LIFE RATIO

▸ PARTIAL BRANCHING FRACTIONS

▸ $\mathit CP$ VIOLATION

▸ $\mathit CP$ AND $\mathit T$ VIOLATION PARAMETERS

▸ $\mathit P$ VIOLATION PARAMETERS

▸ ${{\mathit \Lambda}_{{{b}}}^{0}}$ DECAY PARAMETERS

▸ FORWARD-BACKWARD ASYMMETRIES

▸ ${{\mathit \Lambda}_{{{b}}}^{0}}$ ${{\overline{\mathit \Lambda}}_{{{b}}}^{0}}$ Production Asymmetry

${{\mathit \Lambda}_{{{b}}}^{0}}$ DECAY MODES

The branching fractions B(${{\mathit b}}$ -baryon $\rightarrow$ ${{\mathit \Lambda}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$ anything) and B(${{\mathit \Lambda}_{{{b}}}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$ anything) are not pure measurements because the underlying measured products of these with B(${{\mathit b}}$ $\rightarrow$ ${{\mathit b}}$ -baryon) were used to determine B(${{\mathit b}}$ $\rightarrow$ ${{\mathit b}}$ -baryon), as described in the note ``Production and Decay of ${{\mathit b}}$-Flavored Hadrons.''
For inclusive branching fractions, $\mathit e.g.,$ ${{\mathit \Lambda}_{{{b}}}}$ $\rightarrow$ ${{\overline{\mathit \Lambda}}_{{{c}}}}$ anything, the values usually are multiplicities, not branching fractions. They can be greater than one.

Mode

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

Scale Factor/
Conf. Level

P(MeV/c)

${{\mathit J / \psi}{(1S)}}{{\mathit \Lambda}}{\times }$ B(${{\mathit b}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{b}}}^{0}}$)

($5.8$ $\pm0.8$) $ \times 10^{-5}$

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

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

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

${{\mathit p}}{{\mathit D}^{0}}{{\mathit \pi}^{-}}$

($6.3$ $\pm0.6$) $ \times 10^{-4}$

${{\mathit p}}{{\mathit D}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$

($2.8$ $\pm0.4$) $ \times 10^{-4}$

${{\mathit p}}{{\mathit D}^{*}{(2010)}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$

($5.3$ $\pm1.0$) $ \times 10^{-4}$

${{\mathit \Lambda}_{{{c}}}{(2860)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{{c}}}^{+}}$ $\rightarrow$ ${{\mathit D}^{0}}{{\mathit p}}$

${{\mathit \Lambda}_{{{c}}}{(2880)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{{c}}}^{+}}$ $\rightarrow$ ${{\mathit D}^{0}}{{\mathit p}}$

${{\mathit \Lambda}_{{{c}}}{(2940)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{{c}}}^{+}}$ $\rightarrow$ ${{\mathit D}^{0}}{{\mathit p}}$

${{\mathit p}}{{\mathit D}^{0}}{{\mathit K}^{-}}$

($4.6$ $\pm0.8$) $ \times 10^{-5}$

${{\mathit p}}{{\mathit D}}{{\mathit K}^{-}}$ , ${{\mathit D}}$ $\rightarrow$ ${{\mathit K}^{-}}{{\mathit \pi}^{+}}$

${{\mathit p}}{{\mathit D}}{{\mathit K}^{-}}$ , ${{\mathit D}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit \pi}^{-}}$

${{\mathit p}}{{\mathit J / \psi}}{{\mathit \pi}^{-}}$

($2.6^{+0.5}_{-0.4}$) $ \times 10^{-5}$

${{\mathit p}}{{\mathit \pi}^{-}}{{\mathit J / \psi}}$ , ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$

($1.6$ $\pm0.8$) $ \times 10^{-6}$

${{\mathit p}}{{\mathit J / \psi}}{{\mathit K}^{-}}$

($3.2^{+0.6}_{-0.5}$) $ \times 10^{-4}$

${{\mathit J / \psi}}{{\mathit \Xi}^{-}}{{\mathit K}^{+}}$

${{\mathit p}}{{\mathit \eta}_{{{c}}}{(1S)}}{{\mathit K}^{-}}$

($1.06$ $\pm0.26$) $ \times 10^{-4}$

${{\mathit P}_{{{c {{\overline{\mathit c}}}}}}{(4312)}^{+}}{{\mathit K}^{-}}$ , ${{\mathit P}_{{{c {{\overline{\mathit c}}}}}}^{+}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \eta}_{{{c}}}{(1S)}}$

$<2.5$ $\times 10^{-5}$

${{\mathit P}_{{{c {{\overline{\mathit c}}}}}}{(4380)}^{+}}{{\mathit K}^{-}}$ , ${{\mathit P}_{{{c {{\overline{\mathit c}}}}}}^{+}}$ $\rightarrow$ ${{\mathit p}}{{\mathit J / \psi}}$

($2.7$ $\pm1.4$) $ \times 10^{-5}$

${{\mathit P}_{{{c}}}{(4450)}^{+}}{{\mathit K}^{-}}$ , ${{\mathit P}_{{{c}}}}$ $\rightarrow$ ${{\mathit p}}{{\mathit J / \psi}}$

($1.3$ $\pm0.4$) $ \times 10^{-5}$

${{\mathit \chi}_{{{c1}}}{(1P)}}{{\mathit p}}{{\mathit K}^{-}}$

($7.6^{+1.5}_{-1.3}$) $ \times 10^{-5}$

${{\mathit \chi}_{{{c1}}}{(1P)}}{{\mathit p}}{{\mathit \pi}^{-}}$

($5.0^{+1.3}_{-1.1}$) $ \times 10^{-6}$

${{\mathit \chi}_{{{c2}}}{(1P)}}{{\mathit p}}{{\mathit K}^{-}}$

($7.7^{+1.6}_{-1.4}$) $ \times 10^{-5}$

${{\mathit \chi}_{{{c2}}}{(1P)}}{{\mathit p}}{{\mathit \pi}^{-}}$

($4.8$ $\pm1.9$) $ \times 10^{-6}$

${{\mathit p}}{{\mathit J / \psi}{(1S)}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit K}^{-}}$

($6.6^{+1.3}_{-1.1}$) $ \times 10^{-5}$

${{\mathit p}}{{\mathit \psi}{(2S)}}{{\mathit K}^{-}}$

($6.6^{+1.2}_{-1.0}$) $ \times 10^{-5}$

${{\mathit \chi}_{{{c1}}}{(3872)}}{{\mathit p}}{{\mathit K}^{-}}$

($2.8$ $\pm1.2$) $ \times 10^{-5}$

${{\mathit \chi}_{{{c1}}}{(3872)}}{{\mathit \Lambda}{(1520)}}$

($1.6$ $\pm0.8$) $ \times 10^{-5}$

${{\mathit \psi}{(2S)}}{{\mathit p}}{{\mathit \pi}^{-}}$

($7.5^{+1.6}_{-1.4}$) $ \times 10^{-6}$

${{\mathit p}}{{\overline{\mathit K}}^{0}}{{\mathit \pi}^{-}}$

($1.3$ $\pm0.4$) $ \times 10^{-5}$

${{\mathit p}}{{\mathit K}^{0}}{{\mathit K}^{-}}$

$<3.5$ $\times 10^{-6}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{-}}$

($4.9$ $\pm0.4$) $ \times 10^{-3}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit K}^{-}}$

($3.56$ $\pm0.28$) $ \times 10^{-4}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit a}_{{{1}}}{(1260)}^{-}}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit D}^{-}}$

($4.6$ $\pm0.6$) $ \times 10^{-4}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit D}_{{{s}}}^{-}}$

($1.10$ $\pm0.10$ ) $\%$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit D}_{{{s}}}^{*-}}$

($1.83$ $\pm0.18$ ) $\%$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\overline{\mathit D}}^{0}}{{\mathit K}^{-}}$

($2.13$ $\pm0.20$) $ \times 10^{-3}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\overline{\mathit D}}^{*0}}{{\mathit K}^{-}}$

($6.6$ $\pm0.7$) $ \times 10^{-3}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$

($7.6$ $\pm1.1$) $ \times 10^{-3}$

${{\mathit \Lambda}_{{{c}}}{(2595)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{{c}}}{(2595)}^{+}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$

($3.4$ $\pm1.4$) $ \times 10^{-4}$

${{\mathit \Lambda}_{{{c}}}{(2625)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{{c}}}{(2625)}^{+}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$

($3.3$ $\pm1.3$) $ \times 10^{-4}$

${{\mathit \Sigma}_{{{c}}}{(2455)}^{0}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Sigma}_{{{c}}}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{-}}$

($5.7$ $\pm2.2$) $ \times 10^{-4}$

${{\mathit \Sigma}_{{{c}}}{(2455)}^{++}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$ , ${{\mathit \Sigma}_{{{c}}}^{++}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{+}}$

($3.2$ $\pm1.5$) $ \times 10^{-4}$

${{\mathit \Sigma}_{{{c}}}{(2455)}^{++}}{{\mathit D}^{-}}{{\mathit K}^{-}}$

($6.0$ $\pm0.8$) $ \times 10^{-4}$

${{\mathit \Sigma}_{{{c}}}{(2455)}^{++}}{{\mathit D}^{*-}}{{\mathit K}^{-}}$

($1.36$ $\pm0.22$) $ \times 10^{-3}$

${{\mathit \Sigma}_{{{c}}}{(2520)}^{++}}{{\mathit D}^{-}}{{\mathit K}^{-}}$

($2.8$ $\pm0.5$) $ \times 10^{-4}$

${{\mathit \Sigma}_{{{c}}}{(2520)}^{++}}{{\mathit D}^{*-}}{{\mathit K}^{-}}$

($5.4$ $\pm1.1$) $ \times 10^{-4}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{-}}$

($1.02$ $\pm0.11$) $ \times 10^{-3}$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit p}}{{\overline{\mathit p}}}{{\mathit \pi}^{-}}$

($2.63$ $\pm0.27$) $ \times 10^{-4}$

${{\mathit \Sigma}_{{{c}}}{(2455)}^{0}}{{\mathit p}}{{\overline{\mathit p}}}$ , ${{\mathit \Sigma}_{{{c}}}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{-}}$

($2.3$ $\pm0.5$) $ \times 10^{-5}$

${{\mathit \Sigma}_{{{c}}}{(2520)}^{0}}{{\mathit p}}{{\overline{\mathit p}}}$ , ${{\mathit \Sigma}_{{{c}}}{(2520)}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{-}}$

($3.1$ $\pm0.7$) $ \times 10^{-5}$

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

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$ anything

($10.9$ $\pm2.2$ ) $\%$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$

($6.2^{+1.4}_{-1.3}$ ) $\%$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \tau}^{-}}{{\overline{\mathit \nu}}_{{{\tau}}}}$

($1.9$ $\pm0.5$ ) $\%$

${{\mathit \Lambda}_{{{c}}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$

($5.6$ $\pm3.1$ ) $\%$

${{\mathit \Lambda}_{{{c}}}{(2595)}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$

($7.9^{+4.0}_{-3.5}$) $ \times 10^{-3}$

${{\mathit \Lambda}_{{{c}}}{(2625)}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$

($1.3^{+0.6}_{-0.5}$ ) $\%$

${{\mathit \Sigma}_{{{c}}}{(2455)}^{0}}{{\mathit \pi}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$

${{\mathit \Sigma}_{{{c}}}{(2455)}^{++}}{{\mathit \pi}^{-}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{{\mathit \ell}}}}}}$

${{\mathit p}}{{\mathit h}^{-}}$

$<2.3$ $\times 10^{-5}$

${{\mathit p}}{{\mathit \pi}^{-}}$

($4.6$ $\pm0.8$) $ \times 10^{-6}$

${{\mathit p}}{{\mathit K}^{-}}$

($5.5$ $\pm1.0$) $ \times 10^{-6}$

${{\mathit p}}{{\mathit D}_{{{s}}}^{-}}$

($1.25$ $\pm0.13$) $ \times 10^{-5}$

${{\mathit p}}{{\mathit \mu}^{-}}{{\overline{\mathit \nu}}_{{{\mu}}}}$

($4.1$ $\pm1.0$) $ \times 10^{-4}$

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

($1.08$ $\pm0.28$) $ \times 10^{-6}$

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

($6.9$ $\pm2.5$) $ \times 10^{-8}$

${{\mathit p}}{{\mathit K}^{-}}{{\mathit e}^{+}}{{\mathit e}^{-}}$

($3.1$ $\pm0.6$) $ \times 10^{-7}$

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

($2.6^{+0.5}_{-0.4}$) $ \times 10^{-7}$

${{\mathit \Lambda}{(1520)}^{0}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$

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

($7.1$ $\pm1.7$) $ \times 10^{-6}$

${{\overline{\mathit p}}}{{\mathit K}^{-}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1405)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1520)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1600)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1670)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1690)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1800)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1810)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1820)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1830)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(1890)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(2100)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(2110)}^{0}}{{\mathit \gamma}}$

${{\mathit \Lambda}{(2530)}^{0}}{{\mathit \gamma}}$

(${{\overline{\mathit p}}}{{\mathit K}^{-}}$ ) nonresonant ${{\mathit \gamma}}$

${{\mathit \Lambda}}{{\mathit \eta}}$

($9^{+7}_{-5}$) $ \times 10^{-6}$

${{\mathit \Lambda}}{{\mathit \eta}^{\,'}{(958)}}$

$<3.1$ $\times 10^{-6}$

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

($4.6$ $\pm1.9$) $ \times 10^{-6}$

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

($5.7$ $\pm1.2$) $ \times 10^{-6}$

${{\mathit \Lambda}}{{\mathit K}^{+}}{{\mathit K}^{-}}$

($1.61$ $\pm0.22$) $ \times 10^{-5}$

${{\mathit \Lambda}}{{\mathit D}^{+}}{{\mathit D}^{-}}$

($1.24$ $\pm0.35$) $ \times 10^{-4}$

${{\mathit \Lambda}}{{\mathit \phi}}$

($9.8$ $\pm2.6$) $ \times 10^{-6}$

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

($2.12$ $\pm0.21$) $ \times 10^{-5}$

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

($4.1$ $\pm0.6$) $ \times 10^{-6}$

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

($5.1$ $\pm0.5$) $ \times 10^{-5}$

${{\mathit p}}{{\mathit K}^{-}}{{\mathit K}^{+}}{{\mathit K}^{-}}$

($1.27$ $\pm0.13$) $ \times 10^{-5}$

[1]	${{\mathit P}_{{{c}}}^{+}}$ is a pentaquark-charmonium state.
[2]	Not a pure measurement. See note at head of ${{\mathit \Lambda}_{{{b}}}^{0}}$ Decay Modes.
[3]	Here ${{\mathit h}^{-}}$ means ${{\mathit \pi}^{-}}$ or ${{\mathit K}^{-}}$.

Constrained Fit information

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