اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the matrix elements for the decays $eta^{prime}rightarrowetapi^+pi^-$ and $eta^{prime}rightarrowetapi^0pi^0$
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Based on a sample of $1.31times10^9$ $J/psi$ events collected with the BESIII detector, the matrix elements for the decays $eta^{prime}toetapi^{+}pi^{-}$ and $eta^{prime}toeta pi^{0}pi^{0}$ are determined using 351,016 $eta^{prime}to(etatogammagamma)pi^+pi^-$ and 56,249 $eta^{prime}to(etatogammagamma)pi^0pi^0$ events with background levels less than 1%. Two commonly used representations are used to describe the Dalitz plot density. We find that an assumption of a linear amplitude does not describe the data well. A small deviation of the obtained matrix elements between $eta^{prime}toetapi^{+}pi^{-}$ and $eta^{prime}toeta pi^{0}pi^{0}$ is probably caused by the mass difference between charged and neutral pions or radiative corrections. No cusp structure in $eta^{prime}toeta pi^{0}pi^{0}$ is observed.
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Based on a sample of $1.31 times 10^9$ $J/psi$ events collected with the BESIII detector at the BEPCII collider, Dalitz plot analyses of selected 79,625 $etarightarrowpi^{+}pi^{-}pi^0$ events, 33,908 $etarightarrowpi^0pi^0pi^0$ events and 1,888 $eta^
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