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Measurement of $e^{+}e^{-} to pi^{0}pi^{0}psi(3686)$ at $sqrt{s}$ from 4.009 to 4.600 GeV and observation of a neutral charmoniumlike structure

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 نشر من قبل Yateng Zhang
 تاريخ النشر 2017
  مجال البحث
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Using $e^{+}e^{-}$ collision data collected with the BESIII detector at the BEPCII collider corresponding to an integrated luminosity of 5.2 $fb^{-1}$ at center-of-mass energies ($sqrt{s}$) from 4.009 to 4.600 GeV, the process $e^{+}e^{-} to pi^{0} pi^{0}psi(3686)$ is studied for the first time. The corresponding Born cross sections are measured and found to be half of those of the reaction $e^{+}e^{-} to pi^{+}pi^{-}psi(3686)$. This is consistent with the expectation from isospin symmetry. Furthermore, the Dalitz plots for $pi^{0}pi^{0}psi(3686)$ are accordant with those of $pi^{+}pi^{-}psi(3686)$ at all energy points, and a neutral analogue to the structure in $pi^pm psi(3686)$ around 4040 MeV/$c^{2}$ first observed at $sqrt{s}$=4.416 GeV is observed in the isospin neutral mode at the same energy.



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