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By using 6.32 fbâ1 of data collected with the BESIII detector at center-of-mass energies between 4.178 and 4.226 GeV, we perform an amplitude analysis of the decay D+s ! K0S +â0 and determine the relative fractions and phase differences of different intermediate processes, which include K0S (770)+, K0S (1450)+, Kâ(892)0â+, Kâ(892)+â0, and Kâ(1410)0â+. With the detection efficiency based on the amplitude analysis results, the absolute branching fraction is measured to be B(D+s ! K0S +â0) = (5.43 ± 0.30stat ± 0.15syst) Ă 10â3.
By analyzing 6.32 fb â 1 of e+ eâ annihilation data collected at the center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we determine the branching fraction of the leptonic decay D + s â Ï + ΜÏ, with Ï+ â Ï + Ï0ÂŻÎœÏ, to be B D + s â Ï + Μ Ï = (5.29 ± 0.25 stat ± 0.20 syst) %. We estimate the product of the Cabibbo-Kobayashi-Maskawa matrix element |Vcs|and the D + s decay constant f D + s to be f D + s|Vcs| = (244.8 ± 5.8 stat ± 4.8syst) MeV, using the known values of the Ï + and D + s masses as well as the D + s lifetime, together with our branching fraction measurement. Combining the value of |Vcs| obtained from a global fit in the standard model and f D + s from lattice quantum chromodynamics, we obtain f D + s = (251.6 ± 5.9 stat ± 4.9syst) MeV and |Vcs| = 0.980 ± 0.023 stat ± 0.019 syst. Using the branching fraction of B D + s â ÎŒ + ΜΌ = (5.35±0.21)Ă10â3, we obtain the ratio of the branching fractions B D + s â Ï + ΜÏ/B D +s â ÎŒ+ΜΌ = 9.89±0.71, which is consistent with the standard model prediction of lepton flavor universality.
Using data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.178 to 4.600 GeV, we study the process eĂŸeâ â Ï0Xð3872ĂÎł and search for Zcð4020Ă0 â Xð3872ĂÎł. We find no significant signal and set upper limits on ÏðeĂŸeâ â Ï0Xð3872Ăγà · BðXð3872Ă â ÏĂŸÏâJ=ÏĂ and ÏðeĂŸeâ â Ï0Zcð4020Ă0à · BðZcð4020Ă0 â Xð3872Ăγà · BðXð3872Ă â ÏĂŸÏâJ=ÏĂ for each energy point at 90% confidence level, which is of the order of several tenths pb.
We report a measurement of the observed cross sections of e+ eâ â J/ÏX based on 3.21 fb â 1 of data accumulated at energies from 3.645 to 3.891 GeV with the BESIII detector operated at the BEPCII collider. In analysis of the cross sections, we measured the decay branching fractions of B(Ï(3686) â J/ÏX) = (64.4 ± 0.6 ± 1.6)% and B(Ï(3770) â J/ÏX) = (0.5 ± 0.2 ± 0.1)% for the first time. The energy-dependent line shape of these cross sections cannot be well described by two Breit-Wigner (BW) amplitudes of the expected decays Ï (3686) â J/ÏX and Ï(3770) â J/ÏX. Instead, it can be better described with one more BW amplitude of the decay R(3760)â J/ÏX. Under this assumption, we extracted the R (3760) mass M R (3760 ) = 3766.2 ± 3.8 ± 0.4 MeV/c2, total width Î tot R ( 3760 ) = 22.2 ± 5.9 ± 1.4 MeV, and product of leptonic width and decay branching fraction
ÎeeR(3760) B[R(3760) â J/ÏX] = (79.4 ± 85.5 ± 11.7) eV. The significance of the R(3760) is 5.3Ï. The first uncertainties of these measured quantities are from fits to the cross sections and second systematic.
The electromagnetic process is studied with the initial-state-radiation technique using 7.5 fbâ1 of data collected by the BESIII experiment at seven energy points from 3.773 to 4.600 GeV. The Born cross section and the effective form factor of the proton are measured from the production threshold to 3.0 GeV/ using the invariant-mass spectrum. The ratio of electric and magnetic form factors of the proton is determined from the analysis of the proton-helicity angular distribution.
We measure the inclusive semielectronic decay branching fraction of the D+s meson. A double-tag technique is applied to e+eâ annihilation data collected by the BESIII experiment at the BEPCII collider, operating in the center-of-mass energy range 4.178â4.230 GeV. We select positrons fromD+sâXe+Μe with momenta greater than 200 MeV/c and determine the laboratory momentum spectrum, accounting for the effects of detector efficiency and resolution. The total positron yield and semielectronic branching fraction are determined by extrapolating this spectrum below the momentum cutoff. We measure the D+s semielectronic branching fraction to be(6.30±0.13(stat.)±0.09(syst.)±0.04(ext.))%, showing no evidence for unobserved exclusive semielectronic modes. We combine this result with external data taken from literature to determine the ratio of the D+s and D0 semielectronic widths, Î(D+sâXe+Μe)Î(D0âXe+Μe)=0.790±0.016(stat.)±0.011(syst.)±0.016(ext.). Our results are consistent with and more precise than previous measurements.
Using a sample of (10.09±0.04)Ă109 J/Ï events collected with the BESIII detector, a partial wave analysis of J/ÏâγηâČηâČ is performed.The masses and widths of the observed resonances and their branching fractions are reported. The main contribution is from J/ÏâÎłf0(2020) with f0(2020)âηâČηâČ, which is found with a significance of greater than 25Ï. The product branching fraction B(J/Ï â Îłf0(2020))â
B(f0(2020) â ηâČηâČ is measured to be (2.63±0.06(stat.) + 0.31â0.46(syst.))Ă10â4.
We present the first experimental search for the rare charm decay D0âÏ0ÎœÂŻÎœ. It is based on an e+eâ collision sample consisting of 10.6Ă10^6 pairs of D0ÂŻD0 mesons collected by the BESIII detector at âs=3.773 GeV, corresponding to an integrated luminosity of 2.93 fb^â1. A data-driven method is used to ensure the reliability of the background modeling. No significant D0âÏ0ÎœÂŻÎœ signal is observed in data and an upper limit of the branching fraction is set to be 2.1Ă10^-4 at the 90% confidence level. This is the first experimental constraint on charmed-hadron decays into dineutrino final states.
The Born cross sections of the e+eâ â D*+D*â and e+eâ â D*+Dâ processes are measured using e+eâ collision data collected with the BESIII experiment at center-of-mass energies from 4.085 to 4.600 GeV, corresponding to an integrated luminosity of 15.7 fbâ1. The results are consistent with and more precise than the previous measurements by the Belle, Babar and CLEO collaborations. The measurements are essential for understanding the nature of vector charmonium and charmonium-like states.
Background: Alzheimer's disease is a common debilitating dementia with known heritability, for which 20 late onset susceptibility loci have been identified, but more remain to be discovered. This study sought to identify new susceptibility genes, using an alternative gene-wide analytical approach which tests for patterns of association within genes, in the powerful genome-wide association dataset of the International Genomics of Alzheimer's Project Consortium, comprising over 7 m genotypes from 25,580 Alzheimer's cases and 48,466 controls.
Principal findings: In addition to earlier reported genes, we detected genome-wide significant loci on chromosomes 8 (TP53INP1, p = 1.4Ă10â6) and 14 (IGHV1-67 p = 7.9Ă10â8) which indexed novel susceptibility loci.
Significance: The additional genes identified in this study, have an array of functions previously implicated in Alzheimer's disease, including aspects of energy metabolism, protein degradation and the immune system and add further weight to these pathways as potential therapeutic targets in Alzheimer's disease.