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Observation of a resonant structure in $e^{+}e^{-} to K^{+}K^{-}pi^{0}pi^{0}$

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 نشر من قبل Yateng Zhang
 تاريخ النشر 2020
  مجال البحث
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Using $e^{+}e^{-}$ collision data samples with center-of-mass energies ranging from 2.000 to 2.644 GeV, collected by the BESIII detector at the BEPCII collider, and with a total integrated luminosity of 300 pb^{-1}, a partial-wave analysis is performed for the process $e^{+}e^{-} to K^{+}K^{-}pi^{0}pi^{0}$. The total Born cross sections for the process $e^{+}e^{-} to K^{+}K^{-}pi^{0}pi^{0}$, as well as the Born cross sections f or the subprocesses $e^{+}e^{-} to phi pi^{0}pi^{0}$, $K^{+}(1460)K^{-}$, $K^{+}_{1}(1400)K^{-}$, $K^{+}_{1}(1270)K^{-}$ and $K^{*+}(892)K^{*-}(892)$, are measured versus the center-of-mass energy. The corresponding results for $e^{+}e^{-} to K^{+}K^{-}pi^{0}pi^{0}$ and $phi pi^{0}pi^{0}$ are consistent with those of BaBar and have much improved precision.By analyzing the cross sections for the four subprocesses, $K^{+}(1460)K^{-}$, $K^{+}_{1}(1400)K^{-}$, $K^{+ }_{1}(1270)K^{-}$ and $K^{*+}K^{*-}$, a structure with mass $M$ = (2126.5 $pm$ 16.8 $pm$ 12.4)~MeV/c^{2} and width $Gamma$ = (106.9 $pm$ 32.1 $pm$ 28.1)~MeV is observed with an overall statistical significance of 6.3 $sigma$, although with very limited significance in the subprocesses $e^{+}e^{-} to K^{+}_{1}(1270)K^{-}$ and $K^{*+}(892)K^{*-}(892)$. The resonant parameters of the observed structure suggest it can be identified with the $phi(2170)$, thus the results provide valuable input to the internal nature of the $phi(2170)$.



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