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Utilizing the full CLEO-c data sample of 818 pb$^{-1}$ of $e^+e^-$ data taken at the $psi(3770)$ resonance, we update our measurements of absolute hadronic branching fractions of charged and neutral $D$ mesons. We previously reportedresults from subs ets of these data. Using a double tag technique we obtain branching fractions for three $D^0$ and six $D^+$ modes, including the reference branching fractions $mathcal{B} (D^0to K^-pi^+)=(3.934 pm 0.021 pm 0.061)%$ and $mathcal{B} (D^+ to K^- pi^+pi^+)=(9.224 pm 0.059 pm 0.157)%$. The uncertainties are statistical and systematic, respectively. In these measurements we include the effects of final-state radiation by allowing for additional unobserved photons in the final state, and the systematic errors include our estimates of the uncertainties of these effects. Furthermore, using an independent measurement of the luminosity, we obtain the cross sections $sigma(e^+e^-to D^0overline{D}{}^0)=(3.607pm 0.017 pm 0.056) mathrm{nb}$ and $sigma(e^+e^-to D^+D^-)=(2.882pm 0.018 pm 0.042) mathrm{nb}$ at a center of mass energy, $E_mathrm{cm} = 3774 pm 1$ MeV.
The branching fractions of Ds meson decays serve to normalize many measurements of processes involving charm quarks. Using 586 pb^-1 of e+ e- collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for 13 Ds decays in 16 reconstructed final states with a double tag technique. In particular we make a precise measurement of the branching fraction B(Ds -> K- K+ pi+) = (5.55 +- 0.14 +- 0.13)%, where the uncertainties are statistical and systematic respectively. We find a significantly reduced value of B(Ds -> pi+ pi0 eta) compared to the world average, and our results bring the inclusively and exclusively measured values of B(Ds -> eta X)$ into agreement. We also search for CP-violating asymmetries in Ds decays and measure the cross-section of e+ e- -> Ds* Ds at Ecm = 4.17 GeV.
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