D^(+)→π^(+)v■decay process within the QCDSR approach  

作　　者：陈宇 付海冰 钟涛 吴胜波 黄冬 Yu Chen;Hai-Bing Fu;Tao Zhong;Sheng-Bo Wu;Dong Huang(Department of Physics,Guizhou Minzu University,Guiyang 550025,China;Center of Experimental Training,Guiyang Institute of Information Science and Technology,Guiyang 550025,China)

机构地区：[1]Department of Physics,Guizhou Minzu University,Guiyang 550025,China [2]Center of Experimental Training,Guiyang Institute of Information Science and Technology,Guiyang 550025,China

出　　处：《Chinese Physics C》2024年第6期69-81,共13页中国物理C（英文版）

基　　金：Supported in part by the National Natural Science Foundation of China(12265010,12265009);the Project of Guizhou Provincial Department of Science and Technology(ZK[2021]024,ZK[2023]142)。

摘　　要：In this paper,we investigate the charmed meson rare decay process D^(+)→π^(+)v■using an approach based on QCD sum rules.First,the pion twist-2,3 distribution amplitude(DA)moments<ξ_(2)^(n);|μand<ξ3;π(p,σ),n>|μ,are calculated up to the tenth and fourth orders,respectively,in the QCD sum rules according to the background field theory.After constructing the light-cone harmonic oscillator model for the pion twist-2,3 D As,we obtain their behaviors by matching the calculatedξ-moments.Then,the D→πtransition form factors(TFFs)are calculated using an approach based on QCD light-cone sum rules.The vector form factor at the large recoil region is f_(+)^(D)→^(π)(0)=0.627_(-0.080)^(+0.120).Using the rapidly converging simplified series expansion of z(q^(2),t),we present the TFFs and corresponding angular coefficients in the whole squared momentum transfer physical region.Based on nonstandard neutrino interactions,the■^(0)→π^(+)e■_(e)decay can be related to the■^(0)→π^(+)e■_(e)decay indirectly.Thus,we first describe the semileptonic decay process■^(0)→π^(+)e■_(e),differential decay widths,and branching fraction with B(■^(0)→π^(+)e■_(e))=0.308_(-0.066)^(+0.155)×10^(2).The■^(0)→π^(+)e■_(e)differential/total predictions for forward-backward asymmetry,q^(2)-differential flat terms,and lepton polarization asymmetry are also reported.The prediction for the D^(+)→π^(+)v■branching fraction isB(D^(+)→π^(+)v■)=1.85_(-0.46)+^(0.93)×10^(-8).

关 键 词：transition form factors pion LCDAs flavour changing neutral current transition heavy meson semileptonic decays QCD sum rule 

分 类 号：O572.33[理学—粒子物理与原子核物理]