Production And Decay Of Higher Excited Heavy Mesons

In recent years lots of high orbitally and radially excited heavy mesons are discov-ered in experiments by Belle,BaBar,and LHCb.This has led to great interest in mak-ing assignments within quark model for these experimental measurements,which are the fundamental steps to make further study on these new excited resonances.Besides,some higher excited states predicted in theoretical models are still missing in experiments.In this work,within the frame of Bethe-Salpeter equations and Cornell potential model,we studied the production of D-wave charmed mesons in Bq decays and the strong decay properties of the experimental excited 1-charmed mesons.Bc meson is the only open flavor meson consisting of two heavy quarks and hence could only decay weakly.In the current theoretical studies,there are much works on the decays of Bc to S and P-wave charmonia,while we lack the knowledge of Bc to D-wave charmonia.The experimental ?2?3 823?are very likely to be the 13D2?cc?,while the other two D-wave charmonia ?_c2?1¹D₂?and ?3?13D3?are still missing.On the other hand,the quark models predict that the masses of these three charmonia are all just nearby the DD*threshold,which indicates they all have narrow width and are hopefully to be discovered in experiments.In this work,we will study the semi-leptonic and non-leptonic decays of Bc to these three D-wave charmonia.The BS approach,which could include the important relativistic corrections for higher excited states,are used to calculate the hadronic transition matrix elements.Our results indicate that the branching fractions of D-wave charmonia in Bc decays are in the order of 10-4,which have reached the threshold of the current LHC B factory.These D-wave charmonia are very possible to be discovered in the near future experiments.BaBar and LHCb collaborations recently also discover many excited open flavor charmed mesons,including the potential 2-D2 and 3-states D?s?3.*However,the other D-wave charmed mesons are still missing in experiments.It would be quite important to study the decays of Bq?q=d,s,c?to D-wave heavy-light mesons systematically,which is also an important topic of this work.We calculated the corresponding hadronic transition matrix element with the Salpter wave functions.Several experimental observables,such as the forward-backward symmetries,charged lepton momentum and angular spectra,and semi-leptonic and non-leptonic decay width and branching ratios,are also presented.Our final results indicate that,the branching fractions of B?s?to D-wave cu?s?systems can reach the order of 10-3,and the semi-electronic decay branching fractions of Bc to D-wave charmed mesons are in the order of 10-5.Besides,for the 2-states D2 and D2',which are the mixtures of 1D2-3D2,we presented the variation of semi-electronic decay widths along with the mixing angle.For the completeness of this research,we also calculated the weak decay widths of Bc to the corresponding D-wave bottomed mesons.Besides these D-wave charmed meson,recently the experiments also reported sev-eral excited charm and charm-strange mesons with potential 1-spin-parity,including the D_s1*?2700?+,D_s1*?2860?+,D*?2600?0,D*?2650?0,D₁*?2680?0 and D₁*?2760?0.The previous researches find that,the properties of the two 1-charm-strange mesons are not consistent with the 2S and 1D identification.It is difficult to make them simple 2S?1Lj assignments;in the traditional quark model,above four excited charm mesons should correspond to two 1-?cu?,so the inconsistences in current experiments make the identification much more difficult.In this work,the main strong decay properties of these potential 1-charmed mesons are obtained by BS methods and PC AC relations.Our results reveal that the two 1-charm-strange mesons can be well described by the further 23S1-13D1 mixing scheme with a small mixing angle.D*?2600?0 can also be explained as the 23S1 predominant s-tate with a tiny mixing angle.Considering the mass range,D*?2650?0 and D₁*?2680?0 are more likely to be the 23S1 predominant states,although the total widths under both the 23S 1 and 13D1 assignments have no great conflict with the current experimental data.The calculated width for LHCb D₁*?2760?0 seems about 100 MeV larger than experimental measurement if taking it as 13D1 or 13D1 dominant state cu.The comparisons with other calculations and several important decay ratios are also present.For the identification of these 1-charm mesons,further experimental information,such as ??D??/r?D*??are necessary.