【摘 要】
：
We calculate the D → P transition form factors within the framework of the light-cone QCD sum rules(LCSR)with the D-meson light-cone distribution amplitudes(LCDAs).The next-to-leading power(NLP)correc-tions to the vacuum-to-D-meson correlation function ar
【机 构】
：
School of Physics,Nankai University,Tianjin 300071,China
论文部分内容阅读
We calculate the D → P transition form factors within the framework of the light-cone QCD sum rules(LCSR)with the D-meson light-cone distribution amplitudes(LCDAs).The next-to-leading power(NLP)correc-tions to the vacuum-to-D-meson correlation function are considered,and the NLP corrections from the high-twist D-meson LCDAs and the SU(3)breaking effect from a strange quark mass are investigated.Adopting the exponential model of the D-meson LCDAs,the SU(3)flavor symmetry breaking effects are predicted as RSU(3)+,0=1.12 and RSU(3)T=1.39,respectively,confirming the results obtained from LCSR with pion LCDA.The numerical predic-tions of the form factors show that the contribution from two-particle higher-twist contributions is of great import-ance and the uncertainties are dominated by the inverse moment of φD+(w,μ).With the obtained form factors,the predicted Cabibbo-Kobayashi-Maskawa(CKM)matrix elements are |Vcd|=0.151-0.043+0.091|th.-0.02+0.017|exp and|Vcs|=0.89-0.234+0.467|th.-0.008+0.008|exp.
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