% 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{ $\eta_b$}\ \ \ \ \ \ \ $**$}
\maketitle
The $\eta_b$ is the lightest $b\bar{b}$ state. There is a claim of its discovery, \cite{Yao:2006px}, although this needs confirmation. The mass is taken from \cite{Godfrey:2002rp}  which is higher than the experimental result but in agreement with other potential model calculations. The width is $190$ times the three gluon width of the $\Upsilon(1S)$ calculated using the results of \cite{Godfrey:2002rp} . We assume that the partonic decay to two gluons is the only decay mode. The $\eta_b$ is allowed to be off-shell by ten times the width.
The $\eta_b$ has mass $9397$~MeV and is unstable. The $\eta_b$ has spin $0$, charge $0$ and is colour neutral.
 The $\eta_b$ is a meson and is from the $1^1S_0$ multiplet.The $\eta_b$ has width $8.2$~MeV. The lower limit on the mass of the particle is $82$~MeV and the upper limit is $82$~MeV. These are the deviations from the on-shell value. The branching ratios are fixed.
The properties of the particle and its antiparticle are taken to be charge-conjugate to each other.
 The PDG code is 551.
\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 $\eta_b$ (continues).}
\endfoot
\caption{The decay modes of the $\eta_b$.}
\endlastfoot
\label{tab:551decaymodes}
1.000000 & $**$ & on & $ g, g $  & Partonic decay of $\eta_b$ to two gluons which we assume is the only decay mode.   & Herwig::Quarkonium::QDecayME0 \\ 
\hline
\end{longtable}The $\eta_b$ decay modes are given in Table~\ref{tab:551decaymodes} and the total branching ratio is $1$.


The mass generator is \verb|eta_bmass| for the $\eta_b$.
The width generator is \verb|eta_bwidth| for the $\eta_b$.

\bibliography{particles}


 The particle was checked by Peter Richardson at 21:15:55 on the 20th of October 2007. The most recently changed decay mode was modified at 23:10:55 on the 3rd of April 2005. The particle data was last modified at 22:51:6 on the 23rd of April 2007.

\end{document}
