No Arabic abstract
Born cross sections for the processes $e^+e^- to omegaeta$ and $e^+e^- to omegapi^{0}$ have been determined for center-of-mass energies between 2.00 and 3.08 GeV with the BESIII detector at the BEPCII collider. The results obtained in this work are consistent with previous measurements but with improved precision. Two resonant structures are observed. In the $e^{+}e^{-} to omegaeta$ cross sections, a resonance with a mass of $(2179 pm 21 pm 3)text{MeV}/c^2$ and a width of $(89 pm 28 pm 5)text{MeV}$ is observed with a significance of 6.1$sigma$. Its properties are consistent with the $phi(2170)$. In the $e^{+}e^{-} toomegapi^{0}$ cross sections, a resonance denoted $Y(2040)$ is observed with a significance of more than 10$sigma$. Its mass and width are determined to be $(2034 pm 13 pm 9)text{MeV}/c^2$ and $(234 pm 30 pm 25)text{MeV}$, respectively, where the first uncertainties are statistical and the second ones are systematic.
The process $e^{+}e^{-} rightarrow phieta$ is studied at 22 center-of-mass energy points ($sqrt{s}$) between 2.00 and 3.08 GeV using 715 pb$^{-1}$ of data collected with the BESIII detector. The measured Born cross section of $e^{+}e^{-} rightarrow phieta$ is found to be consistent with {textsl{BABAR}} measurements, but with improved precision. A resonant structure around 2.175 GeV is observed with a significance of 6.9$sigma$ with mass ($2163.5pm6.2pm3.0$) MeV/$c^{2}$ and width ($31.1_{-11.6}^{+21.1}pm1.1$) MeV, where the first uncertainties are statistical and the second are systematic.
The Born cross sections for the process $e^+e^- to eta^prime pi^{+}pi^{-}$ at different center-of-mass energies between $2.00$ and $3.08$~GeV are reported with improved precision from an analysis of data samples collected with the BESIII detector operating at the BEPCII storage ring. An obvious structure is observed in the Born cross section line shape. Fit as a Breit-Wigner resonance, it has a statistical significance of $6.3sigma$ and a mass and width of $M=(2108pm46pm25)$~MeV/$c^2$ and $Gamma=(138pm36pm30)$~MeV, where the uncertainties are statistical and systematic, respectively. These measured resonance parameters agree with the measurements of BABAR in $e^+e^- to eta^prime pi^{+}pi^{-}$ and BESIII in $e^+e^- to omegapi^0$ within two standard deviations.
The process $e^{+}e^{-}to eta^{prime} J/psi$ is observed for the first time with a statistical significance of $8.6sigma$ at center-of-mass energy $sqrt{s} = 4.226$ GeV and $7.3sigma$ at $sqrt{s} = 4.258$ GeV using data samples collected with the BESIII detector. The Born cross sections are measured to be $(3.7 pm 0.7 pm 0.3)$ and $(3.9 pm 0.8 pm 0.3)$ pb at $sqrt{s} = 4.226$ and $4.258$ GeV, respectively, where the first errors are statistical and the second systematic. Upper limits at the 90% confidence level of the Born cross sections are also reported at other 12 energy points.
Using a total of $5.25~{rm fb}^{-1}$ of $e^{+}e^{-}$ collision data with center-of-mass energies from 4.236 to 4.600 GeV, we report the first observation of the process $e^{+}e^{-}to etapsi(2S)$ with a statistical significance of $5sigma$. The data sets were collected by the BESIII detector operating at the BEPCII storage ring. We measure the yield of events integrated over center-of-mass energies and also present the energy dependence of the measured cross section.
The cross sections of the process $e^{+}e^{-} to K_{S}^{0}K_{L}^{0}$ are measured at fifteen center-of-mass energies $sqrt{s}$ from $2.00$ to $3.08~{rm GeV}$ with the BESIII detector at the Beijing Electron Positron Collider (BEPCII). The results are found to be consistent with those obtained by BaBar. A resonant structure around $2.2~{rm GeV}$ is observed, with a mass and width of $2273.7 pm 5.7 pm 19.3~{rm MeV}/c^2$ and $86 pm 44 pm 51~{rm MeV}$, respectively, where the first uncertainties are statistical and the second ones are systematic. The product of its radiative width ($Gamma_{e^+e^-}$) with its branching fraction to $K_{S}^{0}K_{L}^{0}$ ($Br_{K_{S}^{0}K_{L}^{0}}$) is $0.9 pm 0.6 pm 0.7~{rm eV}$.