Which hadronic decay modes are good for $η_b$ searching: double $J/ψ$ or something else?
Abstract
Description
It has been controversial whether $η_b$ can be discovered in Tevatron Run 2 through the decay $η_b\to J/ψJ/ψ$ followed by $J/ψ\to μ^+μ^-$. We clear this controversy by an explicit calculation which predicts ${\rm Br}[η_b\to J/ψJ/ψ]$ to be of order $10^{-8}$. It is concluded that observing eta_b through this decay mode in Tevatron Run 2 is rather unrealistic. The eta_b may be observed in the forthcoming LHC experiments through the 4-lepton channel, if the background events can be significantly reduced by imposing some kinematical cuts. By some rough but plausible considerations, we find that the analogous decay processes eta_b to VV, D^*\bar{D}^* also have very suppressed branching ratios, nevertheless it may be worth looking for η_b at LHC and Super B factory through the decay modes η_b \to K_S K^{\pm}π^{\mp}, D^*\bar{D}.
v2; 28 pages, 2 figures. References added, presentation improved. Discussion on possible nonperturbative mechanism for eta_b->VV added, analysis for eta_b->VP updated by incoprating the U-spin violation effect
v2; 28 pages, 2 figures. References added, presentation improved. Discussion on possible nonperturbative mechanism for eta_b->VV added, analysis for eta_b->VP updated by incoprating the U-spin violation effect