Ablikim, M.Achasov, M. N.Adlarson, P.Ahmed, S.Albrecht, M.Aliberti, R.Çetin, Serkant Ali2024-07-182024-07-1820212470-00102470-0029https://doi.org/10.1103/PhysRevD.104.072005https://hdl.handle.net/11411/7694We propose a new semileptonic tag method to study the doubly Cabibbo-suppressed D decay in psi(3770) -> D (D) over bar reaction. Utilizing the dataset corresponding to an integrated luminosity of 2.93 fb(-1) at a center-of-mass energy of 3.773 GeV collected by the BESIII detector, we determine the branching fraction for D+ -> K+pi(+)pi(-)pi(0) to be (1.03 +/- 0.12(stat) +/- 0.06(syst)) x 10(-3), in which the contributions from narrow intermediate resonances, D+ -> K+eta, D+ -> K+omega, and D+ -> K+phi have been excluded. Combining the world average of the branching fraction of D+ -> K+pi(+)pi(-)pi(0), we determine B(D+ -> K+pi(+)pi(-)pi(0))/B(D+ -> K+pi(+)pi(-)pi(0)) = (1.65 +/- 0.21)%, corresponding to (5.73 +/- 0.73) tan(4)theta(c), where theta(c) is the Cabibbo mixing angle. These results are consistent with our previous measurement with hadronic tags but are significantly larger than other doubly Cabibbo-suppressed decays in the charm sector.eninfo:eu-repo/semantics/openAccessCharmArticle2-s2.0-8511849377210.1103/PhysRevD.104.0720057Q1104Q1WOS:000707477500001