% particle data information automatically produced from the herwig database
\documentclass[a4paper]{article}
\usepackage{cite,longtable}
\bibliographystyle{JHEP}
\topmargin -1.5cm
\textheight 26cm
\textwidth 20cm
\oddsidemargin -2cm
\evensidemargin 0cm
\begin{document}
\title{\boldmath{ $\Lambda_b^0$}\ \ \ \ \ \ \ $***$}
\maketitle
The lightest baryon containing one bottom quark. The mass and lifetime have been measured, albeit with a large error, and are taken from \cite{Yao:2006px}. Only a small number of exclusive decays have been observed and two branching ratios measured. We have therefore chosen to add a number of two body modes with branching ratios calculated from various theoretical papers and model the remaining modes using partonic decays. The ratios of the partonic decays were calculated using the colour factor for the relative rates of the leptonic and direct $b\to c$ decays, colour exchanged decays were added with one third of the rate for the direct decays. The rates of the different quarks produced in the weak decays were calculated using the CKM matrix elements.
The $\Lambda_b^0$ has mass $5624$~MeV and is unstable. The $\Lambda_b^0$ has spin $1/2$, charge $0$ and is colour neutral.
 The $\Lambda_b^0$ is a baryon and is from the $(56,0^+_0)$ $40$plet.The properties of the particle and its antiparticle are taken to be charge-conjugate to each other.
 The decay length is $0.000369$~m. The PDG code is 5122.
\setlongtables
\begin{longtable}[t]{|c|c|c|p{1in}|p{2.5in}|c|}
\hline
Branching & Rating & On/ & Outgoing  & Description & Decayer  \\ 
Ratio     &                                 & Off & Particles &             &         \\ 
\hline
\endhead
\caption{The decay modes of the $\Lambda_b^0$ (continues).}
\endfoot
\caption{The decay modes of the $\Lambda_b^0$.}
\endlastfoot
\label{tab:5122decaymodes}
0.210400 & $**$ & on & $ s, \bar{c}, c, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.207200 & $**$ & on & $ d, \bar{u}, c, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.091300 & $**$ & on & $ c, \bar{u}, d, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.090440 & $**$ & on & $ c, \bar{c}, s, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.066200 & $**$ & on & $ \Lambda_c^+, e^-, \bar{\nu}_e $  & Semi-leptonic decay of $\Lambda_b^0$. The branching ratio was calculated using the partial width from \cite{Ivanov:1996fj} .   & Herwig::SemiLeptonicBaryon::BaryonHeavy1 \\ 
\hline
0.066200 & $**$ & on & $ \Lambda_c^+, \mu^-, \bar{\nu}_\mu $  & Semi-leptonic decay of $\Lambda_b^0$. The branching ratio was calculated using the partial width from \cite{Ivanov:1996fj} .   & Herwig::SemiLeptonicBaryon::BaryonHeavy1 \\ 
\hline
0.037900 & $**$ & on & $ \Lambda_c^+, a_1^-(1260) $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .    & Herwig::BaryonFactorized::BottomBaryonVector \\ 
\hline
0.034300 & $**$ & on & $ \Lambda_c^+, D_s^{*-} $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .   & Herwig::BaryonFactorized::BottomBaryonVector \\ 
\hline
0.029100 & $**$ & on & $ e^-, \bar{\nu}_e, c, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.029100 & $**$ & on & $ \mu^-, \bar{\nu}_\mu, c, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.019100 & $**$ & on & $ \Lambda_c^+, \tau^-, \bar{\nu}_\tau $  & Semi-leptonic decay of $\Lambda_b^0$. The branching ratio was calculated using the form factors from \cite{Ivanov:1996fj}    & Herwig::SemiLeptonicBaryon::BaryonHeavy1 \\ 
\hline
0.014000 & $**$ & on & $ \Lambda_c^+, D_s^- $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .   & Herwig::BaryonFactorized::BottomBaryonScalar \\ 
\hline
0.013600 & $**$ & on & $ \Lambda_c^+, D_{s1}^- $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .   & Herwig::BaryonFactorized::BottomBaryonVector \\ 
\hline
0.013500 & $**$ & on & $ \Lambda_c^+, \rho^- $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .   & Herwig::BaryonFactorized::BottomBaryonVector \\ 
\hline
0.013400 & $**$ & on & $ s, \bar{u}, c, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.012880 & $**$ & on & $ \tau^-, \bar{\nu}_\tau, c, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.012493 & $**$ & on & $ d, \bar{c}, c, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.006000 & $****$ & on & $ \Lambda_c^+, \pi^- $  & Hadronic decay of $\Lambda_b^0$ with branching ratio calculated from the ratio $\Gamma(\Lambda_b\to\Lambda_c\pi)/\Gamma(B_d\to D\pi)=2.2\pm0.4\pm0.3\pm0.7$ taken from \cite{Martin:2004hm} .   & Herwig::BaryonFactorized::BottomBaryonScalar \\ 
\hline
0.004800 & $**$ & on & $ c, \bar{c}, d, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.004800 & $**$ & on & $ c, \bar{u}, s, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.002200 & $**$ & on & $ d, \bar{u}, u, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.002200 & $**$ & on & $ s, \bar{c}, u, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.001600 & $**$ & on & $ \Lambda_c^+, D_{s0}^- $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .   & Herwig::BaryonFactorized::BottomBaryonScalar \\ 
\hline
0.001470 & $**$ & on & $ \Lambda_c^+, D^{*-}(2010) $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .   & Herwig::BaryonFactorized::BottomBaryonVector \\ 
\hline
0.001200 & $**$ & on & $ \Sigma^{*+}_c, \pi^- $  & Hadronic decay of $\Lambda_b^0$ with branching ratio calculated using our rate for the $\Sigma_c\pi$ mode and the rate of $\Gamma(\Lambda_b\to\Sigma_c^*\pi)/\Gamma(\Lambda_b\to\Sigma_c\pi)=2$ from \cite{Leibovich:2003tw} .   & Herwig::Hw64::DecayME0 \\ 
\hline
0.001200 & $**$ & on & $ \Sigma^{*0}_c, \pi^0 $  & Hadronic decay of $\Lambda_b^0$ with branching ratio calculated using our rate for the $\Sigma_c\pi$ mode and the rate of $\Gamma(\Lambda_b\to\Sigma_c^*\pi)/\Gamma(\Lambda_b\to\Sigma_c\pi)=2$ from \cite{Leibovich:2003tw} .   & Herwig::Hw64::DecayME0 \\ 
\hline
0.001000 & $**$ & on & $ \Xi_c^0(2645), K^0 $  & Hadronic decay of $\Lambda_b^0$ with branching ratio calculated using our rate for the ${\Xi'}_cK$ mode and the rate of $\Gamma(\Lambda_b\to\Xi_c^*K)/\Gamma(\Lambda_b\to\Xi_cK)=2$ from \cite{Leibovich:2003tw} .   & Herwig::Hw64::DecayME0 \\ 
\hline
0.001000 & $**$ & on & $ \Sigma^{*+}_c, \rho^- $  & Hadronic decay of $\Lambda_b^0$ with branching ratio calculated using our rate for the $\Sigma_c\rho$ mode and the ratio $\Gamma(\Lambda_b\to\Sigma^*_c\rho)/\Gamma(\Lambda_b\to\Sigma_c\rho)=2$ from \cite{Leibovich:2003tw} .   & Herwig::Hw64::DecayME0 \\ 
\hline
0.001000 & $**$ & on & $ \Sigma^{*0}_c, \rho^0 $  & Hadronic decay of $\Lambda_b^0$ with branching ratio calculated using our rate for the $\Sigma_c\rho$ mode and the ratio $\Gamma(\Lambda_b\to\Sigma^*_c\rho)/\Gamma(\Lambda_b\to\Sigma_c\rho)=2$ from \cite{Leibovich:2003tw} .   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000800 & $**$ & on & $ e^-, \bar{\nu}_e, u, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.000800 & $**$ & on & $ \mu^-, \bar{\nu}_\mu, u, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.000670 & $**$ & on & $ \Lambda_c^+, K^{*-} $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .   & Herwig::BaryonFactorized::BottomBaryonVector \\ 
\hline
0.000600 & $**$ & on & $ \Sigma_c^{+}, \pi^- $  & Hadronic decay of $\Lambda_b^0$ with branching ratio taken from \cite{Ivanov:1997ra}  scaled to give the same value as us for the $\Lambda_c\pi$ mode.   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000600 & $**$ & on & $ \Sigma_c^0, \pi^0 $  & Hadronic decay of $\Lambda_b^0$ with branching ratio taken from \cite{Ivanov:1997ra}  scaled to give the same value as us for the $\Lambda_c\pi$ mode.   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000600 & $*$ & on & $ \Lambda_c(2625)+, \mu^-, \bar{\nu}_\mu $  & Semi-leptonic decay of $\Lambda_b^0$ with branching ratio calculated using the form factors from \cite{Huang:2000xw} .   & Herwig::SemiLeptonicBaryon::ExcitedLambda \\ 
\hline
0.000600 & $**$ & on & $ \Lambda_c(2625)+, e^-, \bar{\nu}_e $  & Semi-leptonic decay of $\Lambda_b^0$ with branching ratio calculated using the form factors from \cite{Huang:2000xw} .   & Herwig::SemiLeptonicBaryon::ExcitedLambda \\ 
\hline
0.000537 & $**$ & on & $ \Lambda_c^+, D^- $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk}    & Herwig::BaryonFactorized::BottomBaryonScalar \\ 
\hline
0.000500 & $**$ & on & $ \Sigma_c^0, \eta' $  & Hadronic decay of $\Lambda_b^0$ with branching ratio taken from \cite{Ivanov:1997ra}  scaled to give the same value as us for the $\Lambda_c\pi$ mode.   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000500 & $**$ & on & $ {\Xi'}_c^0, K^0 $  & Hadronic decay of $\Lambda_b^0$ with branching ratio taken from \cite{Ivanov:1997ra}  scaled to give the same value as us for the $\Lambda_c\pi$ mode.   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000500 & $**$ & on & $ \Sigma_c^0, \rho^0 $  & Hadronic decay of $\Lambda_b^0$ with branching ratio calculated using our rate for the $\Sigma_c\pi$ mode and the ratio $\Gamma(\Lambda_b\to\Sigma_c\pi)/\Gamma(\Lambda_b\to\Sigma_c\rho)=\Gamma(\bar{B}^0\to D^0\pi^0)/\Gamma(\bar{B}^0\to D^0\rho^0)$ from \cite{Leibovich:2003tw}  and the value $1.3$ for this ratio from \cite{Eidelman:2004wy} .   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000500 & $**$ & on & $ \Sigma_c^{+}, \rho^- $  & Hadronic decay of $\Lambda_b^0$ with branching ratio calculated using our rate for the $\Sigma_c\pi$ mode and the ratio $\Gamma(\Lambda_b\to\Sigma_c\pi)/\Gamma(\Lambda_b\to\Sigma_c\rho)=\Gamma(\bar{B}^0\to D^0\pi^0)/\Gamma(\bar{B}^0\to D^0\rho^0)$ from \cite{Leibovich:2003tw}  and the value $1.3$ for this ratio from \cite{Eidelman:2004wy} .   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000470 & $****$ & on & $ \Lambda^0, J/\psi(1S) $  & Decay of $\Lambda_b^0$ with branching ratio from \cite{Yao:2006px}.   & Herwig::BaryonFactorized::BottomBaryonVector \\ 
\hline
0.000430 & $**$ & on & $ \Lambda_c^+, K^- $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the branching ratio for the equivalent $B_d$ decay mode and the ratios from \cite{Datta:2003yk} .   & Herwig::BaryonFactorized::BottomBaryonScalar \\ 
\hline
0.000400 & $**$ & on & $ \Sigma_c^0, \eta $  & Hadronic decay of $\Lambda_b^0$ with branching ratio taken from \cite{Ivanov:1997ra}  scaled to give the same value as us for the $\Lambda_c\pi$ mode.   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000390 & $**$ & on & $ \Lambda^0, \psi(2S) $  & Decay of $\Lambda_b^0$ with branching ratio calculated using the ratio of the partial width to that of $J/\psi\Lambda^0$ from \cite{Cheng:1996cs}  and the \cite{Yao:2006px} rate for $J\psi\Lambda^0$.   & Herwig::BaryonFactorized::BottomBaryonVector \\ 
\hline
0.000300 & $**$ & on & $ \Xi_c^0, K^0 $  & Hadronic decay of $\Lambda_b^0$ with branching ratio taken from \cite{Ivanov:1997ra}  scaled to give the same value as us for the $\Lambda_c\pi$ mode.   & Herwig::Hw64::DecayME0 \\ 
\hline
0.000300 & $**$ & on & $ \tau^-, \bar{\nu}_\tau, u, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.000300 & $**$ & on & $ \Lambda^+_c(2593), e^-, \bar{\nu}_e $  & Semi-leptonic decay of $\Lambda_b^0$ with branching ratio calculated using the form factors from \cite{Huang:2000xw} .   & Herwig::SemiLeptonicBaryon::ExcitedLambda \\ 
\hline
0.000300 & $**$ & on & $ \Lambda^+_c(2593), \mu^-, \bar{\nu}_\mu $  & Semi-leptonic decay of $\Lambda_b^0$ with branching ratio calculated using the form factors from \cite{Huang:2000xw} .   & Herwig::SemiLeptonicBaryon::ExcitedLambda \\ 
\hline
0.000100 & $**$ & on & $ d, \bar{c}, u, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.000100 & $**$ & on & $ s, \bar{u}, u, (ud)_0 $  & Partonic decay of $\Lambda_b^0$.   & Herwig::WeakPartonic::WeakPartonic100 \\ 
\hline
0.000080 & $**$ & on & $ \Lambda_c(2625)+, \tau^-, \bar{\nu}_\tau $  & Semi-leptonic decay of $\Lambda_b^0$ with branching ratio calculated using the form factors from \cite{Huang:2000xw} .   & Herwig::SemiLeptonicBaryon::ExcitedLambda \\ 
\hline
0.000040 & $**$ & on & $ \Lambda^+_c(2593), \tau^-, \bar{\nu}_\tau $  & Semi-leptonic decay of $\Lambda_b^0$ with branching ratio calculated using the form factors from \cite{Huang:2000xw} .   & Herwig::SemiLeptonicBaryon::ExcitedLambda \\ 
\hline
\end{longtable}The $\Lambda_b^0$ decay modes are given in Table~\ref{tab:5122decaymodes} and the total branching ratio is $1$.


 There is no mass generator for the $\Lambda_b^0$.
 There is no width generator for the $\Lambda_b^0$.

\bibliography{particles}


 The particle was checked by Peter Richardson at 9:40:4 on the 4th of February 2009. The most recently changed decay mode was modified at 9:6:19 on the 5th of September 2005. The particle data was last modified at 11:22:40 on the 6th of July 2008.

\end{document}
