D^0-~0 mixing parameter y in the factorization-assisted topological-amplitude approach  

作　　者：Hua-Yu Jiang Fu-Sheng Yu Qin Qin Hsiang-nan Li Cai-Dian Lii 蒋华玉;于福升;秦溱;李湘楠;吕才典(School of Nuclear Science and Technology,Lanzhou University,Lanzhou 730000;Research Center for Hadron and CSR Physics,Lanzhou University and Institute of Modern Physics of CAS Lanzhou 730000;Theoretische Physik 1,Naturwissenschaftlich-Technische Fakultat,Universitat Siegen,Walter-Flex-Strasse 3,D-57068 Siegen;Institute of High Energy Physics,P.O.Box 918(4),Chinese Academy of Sciences,Beijing 100049;Institute of Physics,Academia Sinica,Taipei 11529,)

机构地区：[1]School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 [2]Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS Lanzhou 73000 [3]Theoretische Physik 1, Naturwissenschaftlich-Technische Fakultat, Universitat Siegen, Walter-Flex-Strasse 3 D-57068 Siegen [4]Institute of High Energy Physics, P.O. Box 918（4）, Chinese Academy of Sciences, Beijing 100049 [5]Institute of Physics, Academia Sinica, Taipei 11529,

出　　处：《Chinese Physics C》2018年第6期9-15,共7页中国物理C（英文版）

基　　金：Supported by National Natural Science Foundation of China(11347027,11505083,11375208,11521505,1162113100,11235005,U1732101);Ministry of Science and Technology of R.O.C.(MOST-104-2112-M-001-037-MY3);DFG Forschergruppe FOR 1873"Quark Flavour Physics and Effective Field Theories"

摘　　要：We calculate theD^0-D^-0 mixing parameter y in the factorization-assisted topological-amplitude（FAT）approach, considering contributions from D^0→PP, PV, and VV modes, where P（V） stands for a pseudoscalar（vector） meson. The D^0→PP and PV decay amplitudes are extracted in the FAT approach, and the D^0→VV decay amplitudes with final states in the longitudinal polarization are estimated via the parameter set for D^0→PV. It is found that the VV contribution to y, being of order of 10-4, is negligible, and that the PP and PV contributions amount only up to y_（PP＋PV） =（0.21±0.07）%, a prediction more precise than those previously obtained in the literature,and much lower than the experimental data yexp =（0.61 ±0.08）%. We conclude that D^0 meson decays into other two-body and multi-particle final states are relevant to the evaluation of y, so it is difficult to understand it fully in an exclusive approach.We calculate theD^0-D^-0 mixing parameter y in the factorization-assisted topological-amplitude（FAT）approach, considering contributions from D^0→PP, PV, and VV modes, where P（V） stands for a pseudoscalar（vector） meson. The D^0→PP and PV decay amplitudes are extracted in the FAT approach, and the D^0→VV decay amplitudes with final states in the longitudinal polarization are estimated via the parameter set for D^0→PV. It is found that the VV contribution to y, being of order of 10-4, is negligible, and that the PP and PV contributions amount only up to y_（PP＋PV） =（0.21±0.07）%, a prediction more precise than those previously obtained in the literature,and much lower than the experimental data yexp =（0.61 ±0.08）%. We conclude that D^0 meson decays into other two-body and multi-particle final states are relevant to the evaluation of y, so it is difficult to understand it fully in an exclusive approach.

关 键 词：mixing of charmed mesons strong interactions weak interactions decays of charmed mesons 

分 类 号：O572.33[理学—粒子物理与原子核物理]