Study The Distribution Amplitude Of D Meson Under The QCD Sum Rules

The B?D transition form factor?TFF?f₊^B?D?q²?is determined by the D-meson leading-twist distribution amplitude?DA?,?_2;D,if the proper chiral current correlation function is adopted within the light-cone QCD sum rules.It is therefore significant to make a comprehensive study of DA ?_2;D and its impact on f₊^B?D?q²?.In this paper,we calculate the moments of ?_2;D with the QCD sum rules under the framework of the background field theory.New sum rules for the leading-twist DA moments <???ⁿ>_D to fourth order and up to dimension-six condensates are presented.At the scale ?=2GeV,the values of the first four moments are:<???¹>_D?-0.418_-0.22^+0.021,<???²>_D= 0.289_-0.022^+0.023,...