Recent data on B->p pbar K, K0 pi pi and K Kbar K hint at a $\sim 2.3$ GeV object recoiling against a kaon. This could be the narrow state observed in J/\psi -> gamma xi. Nonobservation in p pbar annihilation implies ${ \cal B}(\xi \to p\bar p) \sim$ few $\times 10^{ -3}$, consistent with eta_c and J/\psi decays, but there are actual hints in p pbar -> phi phi and p p-> p pi^+ pi^- pi^+ pi^- p. Simple modeling shows ${ \cal B}(B \to \xi K){ \cal B}(\xi \to p\bar p) \sim 1\times 10^{ -6}$, appearing as a spike in the $p\bar p$ spectrum, with $\sim$ 30 events per 100 fb$^{ -1}$; modes such as K K_s K_s, K phi phi, K4 pi (K f_2 pi pi) etc. should be explored. The underlying dynamics of g* -> g xi is analogous to g* -> g etaprime or gluon fragmentation. Discovery of sizable B -> xi K could be useful for CP violation studies.
Categories: hep-ph