Eta b meson
= Eta b meson
{title2=$\eta_b$}
A hidden-bottom <pseudoscalar meson>, with leading <quark model> content $b\bar b$. Its lowest configuration has $L=S=J=0$ and $J^{PC}=0^{-+}$. Its net bottom flavor is zero, so annihilation into <gluons> is possible.