摘要
It is interesting to study the characteristics of the whole family of B c which contains two different heavy flavors.LHC and the proposed Z 0 factory provide an opportunity because a large database of the B c family will be achieved.B c and its excited states can be identified via their decay modes.As suggested by experimentalists,B-c (ns) → B c +γ is not easy to be clearly measured,instead,the trajectories of π + and π- occurring in the decay of B c (ns) → B c (ms) + π + π( n 】 m ) can be unambiguously identified,thus the measurement seems easier and more reliable;therefore this mode is more favorable at the early running stage of LHCb and the proposed Z 0 factory.In this work,we calculate the rate of B c (ns) → B c (ms) + π + π-in terms of the QCD multipole-expansion and the numerical results indicate that the experimental measurements with the luminosity of LHC and Z 0 factory are feasible.
It is interesting to study the characteristics of the whole family of B c which contains two different heavy flavors.LHC and the proposed Z 0 factory provide an opportunity because a large database of the B c family will be achieved.B c and its excited states can be identified via their decay modes.As suggested by experimentalists,B-c (ns) → B c +γ is not easy to be clearly measured,instead,the trajectories of π + and π- occurring in the decay of B c (ns) → B c (ms) + π + π( n > m ) can be unambiguously identified,thus the measurement seems easier and more reliable;therefore this mode is more favorable at the early running stage of LHCb and the proposed Z 0 factory.In this work,we calculate the rate of B c (ns) → B c (ms) + π + π-in terms of the QCD multipole-expansion and the numerical results indicate that the experimental measurements with the luminosity of LHC and Z 0 factory are feasible.
基金
supported by the National Natural Science Foundation of China and the special grant for the Ph.D.program of the Chinese Education Ministry
supported by the special grant for new faculty from Tianjin University
