ﻻ يوجد ملخص باللغة العربية
A partial wave analysis (PWA) of the $pi^- pi^- pi^+$ and $pi^- pi^0 pi^0$ systems produced in the reaction $pi^- p to (3pi)^-p$ at 18 GeV/$c$ was carried out using an emph{isobar} model assumption. This analysis is based on 3.0M $pi^- pi^0 pi^0$ events and 2.6M $pi^- pi^-pi^+$ events and shows production of the $a_1(1260)$, $a_2(1320)$, $pi_2(1670)$ and $a_4(2040)$ resonances. Results of detailed studies of the stability of partial wave fits are presented. An earlier analysis of 250K $pi^- pi^- pi^+$ events from the same experiment showed possible evidence for a $J^{PC}=1^{-+}$ exotic meson with a mass of $sim$1.6 GeV/$c^2$ decaying into $rho pi$. In this analysis of a higher statistics sample of the $(3pi)^-$ system in two charged modes we find no evidence of an exotic meson.
Based on a sample of 1.31 billion $J/psi$ events collected with the BESIII detector, we perform a search for the rare decay $etarightarrow 4pi^{0}$ via $J/psirightarrowgammaeta$. No significant $eta$ signal is observed in the invariant mass spectrum
Using a sample of $1.3times 10^9$ $J/psi$ events collected with the BESIII detector, we report the first observation of $eta^{prime}topi^{+}pi^{-}pi^{+}pi^{-}$ and $eta^{prime}topi^{+}pi^{-}pi^{0}pi^{0}$. The measured branching fractions are $mathcal
Using a data sample of $e^+e^-$ collision data corresponding to an integrated luminosity of 2.93 $fb^{-1}$ collected with the BESIII detector at a center-of-mass energy of $sqrt{s}= 3.773~GeV$,we search for the singly Cabibbo-suppressed decays $D^{0}
We report measurements of the observed cross sections for $e^+e^-toomega pi^+pi^-$, $omega K^+K^-$, $omega pbar p$, $K^+K^-rho^0pi^0$, $K^+K^-rho^+pi^-+c.c.$, $K^{*0}K^-pi^+pi^0+c.c.$, $K^{*+}K^-pi^+pi^-+c.c.$, $phipi^+pi^-pi^0$ and $Lambda bar Lambd
We present an amplitude analysis of the decay $D^{0} rightarrow K^{-} pi^{+} pi^{+} pi^{-}$ based on a data sample of 2.93 ${mbox{,fb}^{-1}}$ acquired by the BESIII detector at the $psi(3770)$ resonance. With a nearly background free sample of about