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

INSPIRE

${{\mathit \Lambda}_{{b}}^{0}}$ $I(J^P)$ = $0(1/2^{+})$

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.

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

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

${\mathit \tau}_{{{\mathit \Lambda}_{{b}}^{0}}}/{\mathit \tau}_{{{\mathit B}^{0}}}$ (direct measurements)   $0.964 \pm0.007$

▸ PARTIAL BRANCHING FRACTIONS IN ${{\mathit \Lambda}_{{b}}}$ $\rightarrow$ ${{\mathit \Lambda}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$

▸ $\mathit CP$ 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

${{\mathit A}}$ $_{P}({{\mathit \Lambda}_{{b}}^{0}}$ )   $0.014 \pm0.004$  (S = 1.8)

${{\mathit \Lambda}_{{b}}^{0}}$ 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)   $\Gamma_{1}$ ${{\mathit J / \psi}{(1S)}}{{\mathit \Lambda}}{\times }$ B( ${{\mathit b}}$ $\rightarrow$ ${{\mathit \Lambda}_{{b}}^{0}}$ )   $(5.8\pm{0.8})\times 10^{-5}$ 1740   $\Gamma_{2}$ ${{\mathit J / \psi}{(1S)}}{{\mathit \Lambda}}$   1740   $\Gamma_{3}$ ${{\mathit J / \psi}{(1S)}}{{\mathit \Lambda}}{{\mathit \phi}}$   1010   $\Gamma_{4}$ ${{\mathit \psi}{(2S)}}{{\mathit \Lambda}}$   1298   $\Gamma_{5}$ ${{\mathit p}}{{\mathit D}^{0}}{{\mathit \pi}^{-}}$   $(6.3\pm{0.6})\times 10^{-4}$ 2370   $\Gamma_{6}$ ${{\mathit \Lambda}_{{c}}{(2860)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{c}}^{+}}$ $\rightarrow$ ${{\mathit D}^{0}}{{\mathit p}}$       $\Gamma_{7}$ ${{\mathit \Lambda}_{{c}}{(2880)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{c}}^{+}}$ $\rightarrow$ ${{\mathit D}^{0}}{{\mathit p}}$       $\Gamma_{8}$ ${{\mathit \Lambda}_{{c}}{(2940)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{c}}^{+}}$ $\rightarrow$ ${{\mathit D}^{0}}{{\mathit p}}$       $\Gamma_{9}$ ${{\mathit p}}{{\mathit D}^{0}}{{\mathit K}^{-}}$   $(4.6\pm{0.8})\times 10^{-5}$ 2269   $\Gamma_{10}$ ${{\mathit p}}{{\mathit D}}{{\mathit K}^{-}}$ , ${{\mathit D}}$ $\rightarrow$ ${{\mathit K}^{-}}{{\mathit \pi}^{+}}$       $\Gamma_{11}$ ${{\mathit p}}{{\mathit D}}{{\mathit K}^{-}}$ , ${{\mathit D}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit \pi}^{-}}$       $\Gamma_{12}$ ${{\mathit p}}{{\mathit J / \psi}}{{\mathit \pi}^{-}}$   $(2.6^{+0.5}_{-0.4})\times 10^{-5}$ 1755   $\Gamma_{13}$ ${{\mathit p}}{{\mathit \pi}^{-}}{{\mathit J / \psi}}$ , ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$   $(1.6\pm{0.8})\times 10^{-6}$     $\Gamma_{14}$ ${{\mathit p}}{{\mathit J / \psi}}{{\mathit K}^{-}}$   $(3.2^{+0.6}_{-0.5})\times 10^{-4}$ 1589   $\Gamma_{15}$ ${{\mathit p}}{{\mathit \eta}_{{c}}{(1S)}}{{\mathit K}^{-}}$   $(1.06\pm{0.26})\times 10^{-4}$ 1670   $\Gamma_{16}$ ${{\mathit P}_{{c}}{(4312)}^{+}}{{\mathit K}^{-}}$ , ${{\mathit P}_{{c}}{(4312)}^{+}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \eta}_{{c}}{(1S)}}$   $<2.5\times 10^{-5}$ CL=95%     $\Gamma_{17}$ ${{\mathit P}_{{c}}{(4380)}^{+}}{{\mathit K}^{-}}$ , ${{\mathit P}_{{c}}}$ $\rightarrow$ ${{\mathit p}}{{\mathit J / \psi}}$  [1] $(2.7\pm{1.4})\times 10^{-5}$     $\Gamma_{18}$ ${{\mathit P}_{{c}}{(4450)}^{+}}{{\mathit K}^{-}}$ , ${{\mathit P}_{{c}}}$ $\rightarrow$ ${{\mathit p}}{{\mathit J / \psi}}$  [1] $(1.3\pm{0.4})\times 10^{-5}$     $\Gamma_{19}$ ${{\mathit \chi}_{{c1}}{(1P)}}{{\mathit p}}{{\mathit K}^{-}}$   $(7.6^{+1.5}_{-1.3})\times 10^{-5}$ 1242   $\Gamma_{20}$ ${{\mathit \chi}_{{c1}}{(1P)}}{{\mathit p}}{{\mathit \pi}^{-}}$   $(5.0^{+1.3}_{-1.1})\times 10^{-6}$ 1462   $\Gamma_{21}$ ${{\mathit \chi}_{{c2}}{(1P)}}{{\mathit p}}{{\mathit K}^{-}}$   $(7.9^{+1.6}_{-1.4})\times 10^{-5}$ 1198   $\Gamma_{22}$ ${{\mathit \chi}_{{c2}}{(1P)}}{{\mathit p}}{{\mathit \pi}^{-}}$   $(4.8\pm{1.9})\times 10^{-6}$ 1427   $\Gamma_{23}$ ${{\mathit p}}{{\mathit J / \psi}{(1S)}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit K}^{-}}$   $(6.6^{+1.3}_{-1.1})\times 10^{-5}$ 1410   $\Gamma_{24}$ ${{\mathit p}}{{\mathit \psi}{(2S)}}{{\mathit K}^{-}}$   $(6.6^{+1.2}_{-1.0})\times 10^{-5}$ 1063   $\Gamma_{25}$ ${{\mathit \chi}_{{c1}}{(3872)}}{{\mathit p}}{{\mathit K}^{-}}$   $(3.2\pm{1.4})\times 10^{-5}$ 837   $\Gamma_{26}$ ${{\mathit \chi}_{{c1}}{(3872)}}{{\mathit \Lambda}{(1520)}}$   $(1.9\pm{0.9})\times 10^{-5}$ 721   $\Gamma_{27}$ ${{\mathit \psi}{(2S)}}{{\mathit p}}{{\mathit \pi}^{-}}$   $(7.5^{+1.6}_{-1.4})\times 10^{-6}$ 1320   $\Gamma_{28}$ ${{\mathit p}}{{\overline{\mathit K}}^{0}}{{\mathit \pi}^{-}}$   $(1.3\pm{0.4})\times 10^{-5}$ 2693   $\Gamma_{29}$ ${{\mathit p}}{{\mathit K}^{0}}{{\mathit K}^{-}}$   $<3.5\times 10^{-6}$ CL=90% 2639   $\Gamma_{30}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{-}}$   $(4.9\pm{0.4})\times 10^{-3}$ S=1.2  2342   $\Gamma_{31}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit K}^{-}}$   $(3.56\pm{0.28})\times 10^{-4}$ S=1.2  2314   $\Gamma_{32}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit a}_{{1}}{(1260)}^{-}}$   seen 2153   $\Gamma_{33}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit D}^{-}}$   $(4.6\pm{0.6})\times 10^{-4}$ 1886   $\Gamma_{34}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit D}_{{s}}^{-}}$   $(1.10\pm{0.10})\%$ 1833   $\Gamma_{35}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$   $(7.6\pm{1.1})\times 10^{-3}$ S=1.1  2323   $\Gamma_{36}$ ${{\mathit \Lambda}_{{c}}{(2595)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{c}}{(2595)}^{+}}$ $\rightarrow$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$   $(3.4\pm{1.4})\times 10^{-4}$ 2210   $\Gamma_{37}$ ${{\mathit \Lambda}_{{c}}{(2625)}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Lambda}_{{c}}{(2625)}^{+}}$ $\rightarrow$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$   $(3.3\pm{1.3})\times 10^{-4}$ 2193   $\Gamma_{38}$ ${{\mathit \Sigma}_{{c}}{(2455)}^{0}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ , ${{\mathit \Sigma}_{{c}}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{-}}$   $(5.7\pm{2.2})\times 10^{-4}$ 2265   $\Gamma_{39}$ ${{\mathit \Sigma}_{{c}}{(2455)}^{++}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$ , ${{\mathit \Sigma}_{{c}}^{++}}$ $\rightarrow$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{+}}$   $(3.2\pm{1.5})\times 10^{-4}$ 2265   $\Gamma_{40}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{-}}$   $(1.02\pm{0.11})\times 10^{-3}$ 2184   $\Gamma_{41}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit p}}{{\overline{\mathit p}}}{{\mathit \pi}^{-}}$   $(2.63\pm{0.27})\times 10^{-4}$ 1805   $\Gamma_{42}$ ${{\mathit \Sigma}_{{c}}{(2455)}^{0}}{{\mathit p}}{{\overline{\mathit p}}}$ , ${{\mathit \Sigma}_{{c}}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{-}}$   $(2.3\pm{0.5})\times 10^{-5}$     $\Gamma_{43}$ ${{\mathit \Sigma}_{{c}}{(2520)}^{0}}{{\mathit p}}{{\overline{\mathit p}}}$ , ${{\mathit \Sigma}_{{c}}{(2520)}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{-}}$   $(3.1\pm{0.7})\times 10^{-5}$     $\Gamma_{44}$ ${{\mathit \Lambda}}{{\mathit K}^{0}}$2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$   2591   $\Gamma_{45}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{\mathit \ell}}}}}$ anything  [2] $(10.9\pm{2.2})\%$     $\Gamma_{46}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{\mathit \ell}}}}}$   $(6.2^{+1.4}_{-1.3})\%$ 2345   $\Gamma_{47}$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{\mathit \ell}}}}}$   $(5.6\pm{3.1})\%$ 2335   $\Gamma_{48}$ ${{\mathit \Lambda}_{{c}}{(2595)}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{\mathit \ell}}}}}$   $(7.9^{+4.0}_{-3.5})\times 10^{-3}$ 2212   $\Gamma_{49}$ ${{\mathit \Lambda}_{{c}}{(2625)}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{\mathit \ell}}}}}$   $(1.3^{+0.6}_{-0.5})\%$ 2195   $\Gamma_{50}$ ${{\mathit \Sigma}_{{c}}{(2455)}^{0}}{{\mathit \pi}^{+}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{\mathit \ell}}}}}$   2272   $\Gamma_{51}$ ${{\mathit \Sigma}_{{c}}{(2455)}^{++}}{{\mathit \pi}^{-}}{{\mathit \ell}^{-}}{{\overline{\mathit \nu}}_{{{{\mathit \ell}}}}}$   2272   $\Gamma_{52}$ ${{\mathit p}}{{\mathit h}^{-}}$  [3] $<2.3\times 10^{-5}$ CL=90% 2730   $\Gamma_{53}$ ${{\mathit p}}{{\mathit \pi}^{-}}$   $(4.5\pm{0.8})\times 10^{-6}$ 2730   $\Gamma_{54}$ ${{\mathit p}}{{\mathit K}^{-}}$   $(5.4\pm{1.0})\times 10^{-6}$ 2709   $\Gamma_{55}$ ${{\mathit p}}{{\mathit D}_{{s}}^{-}}$   $<4.8\times 10^{-4}$ CL=90% 2364   $\Gamma_{56}$ ${{\mathit p}}{{\mathit \mu}^{-}}{{\overline{\mathit \nu}}_{{\mu}}}$   $(4.1\pm{1.0})\times 10^{-4}$ 2730   $\Gamma_{57}$ ${{\mathit \Lambda}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$   $(1.08\pm{0.28})\times 10^{-6}$ 2695   $\Gamma_{58}$ ${{\mathit p}}{{\mathit \pi}^{-}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$   $(6.9\pm{2.5})\times 10^{-8}$ 2720   $\Gamma_{59}$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit e}^{+}}{{\mathit e}^{-}}$   $(3.1\pm{0.6})\times 10^{-7}$ 2708   $\Gamma_{60}$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$   $(2.6^{+0.5}_{-0.4})\times 10^{-7}$ 2685   $\Gamma_{61}$ ${{\mathit \Lambda}}{{\mathit \gamma}}$   $(7.1\pm{1.7})\times 10^{-6}$ 2699   $\Gamma_{62}$ ${{\mathit \Lambda}}{{\mathit \eta}}$   $(9^{+7}_{-5})\times 10^{-6}$ 2670   $\Gamma_{63}$ ${{\mathit \Lambda}}{{\mathit \eta}^{\,'}{(958)}}$   $<3.1\times 10^{-6}$ CL=90% 2611   $\Gamma_{64}$ ${{\mathit \Lambda}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$   $(4.6\pm{1.9})\times 10^{-6}$ 2692   $\Gamma_{65}$ ${{\mathit \Lambda}}{{\mathit K}^{+}}{{\mathit \pi}^{-}}$   $(5.6\pm{1.2})\times 10^{-6}$ 2660   $\Gamma_{66}$ ${{\mathit \Lambda}}{{\mathit K}^{+}}{{\mathit K}^{-}}$   $(1.60\pm{0.22})\times 10^{-5}$ 2605   $\Gamma_{67}$ ${{\mathit \Lambda}}{{\mathit \phi}}$   $(9.8\pm{2.6})\times 10^{-6}$ 2599   $\Gamma_{68}$ ${{\mathit p}}{{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$   $(2.10\pm{0.22})\times 10^{-5}$ 2715   $\Gamma_{69}$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit K}^{+}}{{\mathit \pi}^{-}}$   $(4.0\pm{0.6})\times 10^{-6}$ 2612   $\Gamma_{70}$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$   $(5.0\pm{0.5})\times 10^{-5}$ 2675   $\Gamma_{71}$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit K}^{+}}{{\mathit K}^{-}}$   $(1.26\pm{0.13})\times 10^{-5}$ 2524
FOOTNOTES

Constrained Fit information