Amplitude Analysis Of The Decay D⁰?2(?⁺?^-)and Study Of The Decay D_s⁺?K_S,L⁰K⁺ At BES?

D meson decay plays an important role in the studies of non-perturbative QCD,weak interation,precision test of standard model and exploration of physics beyond the standard model.BESIII has collected large data near the threshold of DD pair,which provide unique laboratory to study the charmed meson decay.Based on the data collected by BES?,we perform two studies about charmed meson hadronice decay.Based on 2.93 fb-1 data taken at 3.773 GeV by BESIII,the amplitude anlysis as well as model dependent CP-even fraction and branching fraction measurements of D0??+?-?+?-are performed.The dominated contributions of D0??+?-?+?-are D0?a1(1260)+?-,D0??(770)0?(770)0,where the D-wave in D0??(770)0?(770)0 is dominated.The CP-even fraction of D0??+?-?+?-calculated by the amplitude model of this work is obtained to be(73.2±0.9stat.±0.7syst.±1.2model)%which is consistent with CLEOc's results.With double tag method,the branching fraction of D0??+?-?+?-is mearsured to be(0.704±0.009stat.±0.013syst.)%,which is con-sistent with the PDG value within 3?.These results are expected to provide important information in binning strong phase parameter mearsurement of D0??+?-?+?-as well as CKM angle ?(?3)determination in B-?DK-decays.Using an e+e-annihilation data sample corresponding to an integrated luminos-ity of 3.19 fb-1 and collected at a center-of-mass energy(?)=4.178 GeV with the BES? detector,we measured the absolute branching fractions B(Ds+?KS0K+)=(1.425±0.038stat.±0.031syst.)%and B(Ds+?KL0K+)=(1.485±0.039stat.±0.046syst.)%.The branching fraction of Ds+?KS0K+ is compatible with the world average and that of Ds+?KL0K+ is measured for the first time.We present the first measurement of the KS0-KL0 asymmetry in the decays Ds+?KS,L0K+,and R(Ds+?KS,L0K+)=B(Ds+?KS0K+)-B(Ds+?KL0K+)/B(Ds+?KS0K+)-B(Ds+?KL0K+)=(-2.1±1.9stat.±1.6syst.)%.In addition,we measured the direct CP asymmetries ACP(Ds±?KS0K±)=(0.6±2.8stat.±0.6syst.)%and ACP(Ds±?KL0Kq)=(-1.1±2.6stat.±0.6syst.)%.