%0 Journal Article
%A Bali, Gunnar S.
%A Collins, Sara
%A Dürr, Stephan
%A Kanamori, Issaku
%T D s → η , η ′ semileptonic decay form factors with disconnected quark loop contributions
%J Physical review / D
%V 91
%N 1
%@ 1550-7998
%C [S.l.]
%I Soc.
%M FZJ-2015-05042
%P 014503
%D 2015
%X We calculate for the first time the form factors of the semileptonic decays of the Ds meson to η and η′ using lattice techniques. As a by-product of the calculation we obtain the masses and leading distribution amplitudes of the η and η′ mesons. We use Nf=2+1 nonperturbatively improved clover fermions on configurations with a lattice spacing a∼0.075  fm. We are able to obtain clear signals for relevant matrix elements, using several noise reduction techniques, for both the connected and the disconnected contributions. This includes a new method for reducing the variance of pseudoscalar disconnected two-point functions. At zero momentum transfer, we obtain for the scalar form factors, |fDs→η0|=0.564(11) and |fDs→η′0|=0.437(18) at Mπ≈470  MeV, as well as |fDs→η0|=0.542(13) and |fDs→η′0|=0.404(25) at Mπ≈370  MeV, where the errors are statistical only.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000348157800005
%R 10.1103/PhysRevD.91.014503
%U https://juser.fz-juelich.de/record/202895