We measure the absolute branching fractions of Ds semileptonic decays where the hadron in the final state is one of &phis;, η, η', K0S , K☆0, and f 0, using 2.8 × 105 e+ e– → Ds D⋆s decays collected in the CLEO-c detector at a center-of-mass energy close to 4170 MeV. We obtain B ( D+s → &phis;e+νe ) = (2.29 ± 0.37 ± 0.11)%, B ( D+s → ηe+νe) = (2.48 ± 0.29 ± 0.13)%, B ( D+s → η'e+νe ) = (0.91 ± 0.33 ± 0.05)%, where the first uncertainties are statistical and the second are systematic. We also obtain B ( D+s → K0e +νe) = (0.37 ± 0.10 ± 0.02)%, and B ( D+s → K☆0e +νe) = (0.18 ± 0.07 ± 0.01)%, which are the first measurements of Cabibbo suppressed exclusive Ds semileptonic decays, and, B ( D+s → f0e+ νe) × B (f0 → π+π –) = (0.13 ± 0.04 ± 0.01)%. This is the first direct evidence of a semileptonic decay including a scalar meson in the final state.
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