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Experimental study of psi decays to K+K- pi^0 and K+K- eta

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 نشر من قبل RongGang Ping
 تاريخ النشر 2012
  مجال البحث
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Using $(106pm4)times 10^6$ $psip$ events accumulated with the BESIII detector at the BEPCII $e^+e^-$ collider, we present measurements of the branching fractions for psi decays to $K^{+}K^{-}pi^{0}$ and $K^{+}K^{-}eta$. In these final states, the decay $psito K_2^{*}(1430)^+K^-+c.c.$ is observed for the first time, and its branching fraction is measured to be $(7.12pm{0.62}{rm (stat.)}^{+1.13}_{-0.61}{rm (syst.)})times 10^{-5}$, which indicates a violation of the helicity selection rule in $psip$ decays. The branching fractions of $psito K^*(892)^+K^-+c.c., phieta, phipi^0$ are also measured. The measurements are used to test the QCD predictions on charmonium decays.

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