Speaker
Description
We have studied the production of ground and excited axial charmonia in processes, $e^- e^+ \rightarrow h_c(nP) + \eta_c(n'S)$, and $e^- e^+ \rightarrow \chi_{c1}(nP) + h_c(n'P)$ [1] for $n,n'=1,2$, through leading order (LO) tree-level diagrams $\sim O(\alpha_{em} \alpha_s)$, which proceed through exchange of a virtual photon and an internal gluon line connecting two quark lines in the triangle quark loop part of the diagram at center of mass energy, $\sqrt{s}=10.6 GeV$ . We employ the framework of $4\times 4$ Bethe-Salpeter equation, and calculate their cross sections [1], which are compared with recent NRQCD and Relativistic quark model calculations. For both the above processes, we have drawn plots of total cross sections versus $\sqrt{s}$ for $n,n'=1,2$, as well as plots of differential cross section versus $cos\Theta$ at different center of mass energies. These studies might be of interest for future experiments at B-factories, since $h_c, \eta_c$, and $\chi_{c1}, h_c$ production might provide opportunities for observing $h_c$ with higher statistics in future. Also our cross sections may provide guidance for future experiments at B-factories.
Reference:
[1] M.Narang, S.Bhatnagar, Few-Body Syst. 64, 82 (2023).
