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Precise Measurements of Branching Fractions for $D_s^+$ Meson Decays to Two Pseudoscalar Mesons

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 نشر من قبل Ziyi Wang
 تاريخ النشر 2020
  مجال البحث
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We measure the branching fractions for seven $D_{s}^{+}$ two-body decays to pseudo-scalar mesons, by analyzing data collected at $sqrt{s}=4.178sim4.226$ GeV with the BESIII detector at the BEPCII collider. The branching fractions are determined to be $mathcal{B}(D_s^+to K^+eta^{prime})=(2.68pm0.17pm0.17pm0.08)times10^{-3}$, $mathcal{B}(D_s^+toeta^{prime}pi^+)=(37.8pm0.4pm2.1pm1.2)times10^{-3}$, $mathcal{B}(D_s^+to K^+eta)=(1.62pm0.10pm0.03pm0.05)times10^{-3}$, $mathcal{B}(D_s^+toetapi^+)=(17.41pm0.18pm0.27pm0.54)times10^{-3}$, $mathcal{B}(D_s^+to K^+K_S^0)=(15.02pm0.10pm0.27pm0.47)times10^{-3}$, $mathcal{B}(D_s^+to K_S^0pi^+)=(1.109pm0.034pm0.023pm0.035)times10^{-3}$, $mathcal{B}(D_s^+to K^+pi^0)=(0.748pm0.049pm0.018pm0.023)times10^{-3}$, where the first uncertainties are statistical, the second are systematic, and the third are from external input branching fraction of the normalization mode $D_s^+to K^+K^-pi^+$. Precision of our measurements is significantly improved compared with that of the current world average values.



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