No abstract

In an analysis of a 2.92 fb −1 data sample taken at 3.773 GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions B(D 0 → K − e + νe) = (3.505 ± 0.014 ± 0.033)% and B(D 0 → π − e + νe) = (0.295 ± 0.004 ± 0.003)%. From a study of the differential decay rates we obtain the products of hadronic form factor and the magnitude of the CKM matrix element f ), we determine the ratio |V cd |/|Vcs| = 0.238 ± 0.004 ± 0.002 ± 0.011, where the third error is from the uncertainty in the LCSR normalization. In addition, we measure form factor parameters for three different theoretical models that describe the weak hadronic charged currents for these two semileptonic decays. All of these measurements are the most precise to date.

fitter is utilized to improve the measured precision. Among the measurements for twelve Λ decay mode j, the ST yield is determined to bewhereis the total number of produced Λ where ε ij is the efficiency for simultaneously reconstruct- Because of the large acceptance of the BESIII detec-182 tor and the low multiplicities of Λ c hadronic decays, whereis the average DT efficiency

The Born cross section for the process e þ e − → pp is measured using the initial state radiation technique with an undetected photon. This analysis is based on datasets corresponding to an integrated luminosity of 7.5 fb −1 , collected with the BESIII detector at the BEPCII collider at center of mass energies between 3.773 and 4.600 GeV. The Born cross section for the process e þ e − → pp and the proton effective form factor are determined in the pp invariant mass range between 2.0 and 3.8 GeV=c 2 divided into 30 intervals. The proton form factor ratio (jG E j=jG M j) is measured in 3 intervals of the pp invariant mass between 2.0 and 3.0 GeV=c 2 .

No abstract