Excited Heavy Quarkonium Production at the LHC through $W$-Boson Decays

Abstract

Sizable amount of heavy-quarkonium events can be produced through $W$-boson decays at the LHC. Such channels will provide a suitable platform to study the heavy-quarkonium properties. The "improved trace technology", which disposes the amplitude $\mathcal{M}$ at the amplitude-level, is helpful for deriving compact analytical results for complex processes. As an important new application, in addition to the production of the lower-level Fock states $|(Q\overline{Q^{\prime }})[1S]>$ and $|(Q\overline{Q^{\prime }})[1P]>$, we make a further study on the production of higher-excited $|(Q\overline{Q^{\prime }})>$-quarkonium Fock states $|(Q\overline{Q^{\prime }})[2S]>$, $|(Q\overline{Q^{\prime }})[3S]>$ and $|(Q\overline{Q^{\prime }})[2P]>$. Here $|(Q\overline{Q^{\prime }})>$ stands for the $|(c\bar{c})>$-charmonium, $|(c\bar{b})>$-quarkonium and $|(b\bar{b})>$-bottomonium respectively. We show that sizable amount of events for those higher-excited states can also be produced at the LHC. Therefore, we need to take them into consideration for a sound estimation.

7 pages, 9 figures and 6 tables. Typo errors are corrected, more discussions and two new figures have been added