@article{d732523c38c3411aba84f06176dada0c,

title = "First Measurement of the Form Factors in Ds+ →k0e+νe and Ds+ →k∗0e+νe Decays",

abstract = "We report on new measurements of Cabibbo-suppressed semileptonic Ds+ decays using 3.19 fb-1 of e+e-annihilation data sample collected at a center-of-mass energy of 4.178 GeV with the BESIII detector at the BEPCII collider. Our results include branching fractions B(Ds+→K0e+νe)=[3.25±0.38(stat)±0.16(syst)]×10-3 and B(Ds+→K∗0e+νe)=[2.37±0.26(stat)±0.20(syst)]×10-3, which are much improved relative to previous measurements, and the first measurements of the hadronic form-factor parameters for these decays. For Ds+→K0e+νe, we obtain f+(0)=0.720±0.084(stat)±0.013(syst), and for Ds+→K∗0e+νe, we find form-factor ratios rV=V(0)/A1(0)=1.67±0.34(stat)±0.16(syst) and r2=A2(0)/A1(0)=0.77±0.28(stat)±0.07(syst).",

keywords = "UB-VERTICAL-BAR, SEMILEPTONIC-B, HEAVY",

author = "{BESIII Collaboration} and M. Ablikim and Achasov, {M. N.} and S. Ahmed and M. Albrecht and M. Alekseev and A. Amoroso and An, {F. F.} and Q. An and Y. Bai and O. Bakina and {Baldini Ferroli}, R. and Y. Ban and K. Begzsuren and Bennett, {D. W.} and Bennett, {J. V.} and N. Berger and M. Bertani and D. Bettoni and F. Bianchi and E. Boger and I. Boyko and Briere, {R. A.} and H. Cai and X. Cai and A. Calcaterra and Cao, {G. F.} and Cetin, {S. A.} and J. Chai and Chang, {J. F.} and Chang, {W. L.} and G. Chelkov and G. Chen and Chen, {H. S.} and Chen, {J. C.} and Chen, {M. L.} and Chen, {P. L.} and Chen, {S. J.} and Chen, {X. R.} and Chen, {Y. B.} and W. Cheng and Chu, {X. K.} and G. Cibinetto and F. Cossio and Dai, {H. L.} and Dai, {J. P.} and A. Dbeyssi and D. Dedovich and Deng, {Z. Y.} and Muchnoi, {N. Yu} and Nikolaev, {I. B.}",

year = "2019",

month = feb,

day = "15",

doi = "10.1103/PhysRevLett.122.061801",

language = "English",

volume = "122",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society",

number = "6",

}