arXiv subjects

M. Ablikim et al.

Publications and source records attributed to M. Ablikim et al..

3 recordsLinked to original sources

arXiv2006

Precison Measurements of the Mass, the Widths of $ψ(3770)$ Resonance and the Cross Section $σ[e^+e^-\to ψ(3770)]$ at $E_{\rm cm}=3.7724$ GeV

By analyzing the $R$ values measured at 68 energy points in the energy region between 3.650 and 3.872 GeV reported in our previous paper, we have precisely measured the mass, the total width, the leptonic width and the leptonic decay branching fraction of the $ψ(3770)$ to be ${M}_{ψ(3770)}=3772.4 \pm 0.4 \pm 0.3$ MeV, $Γ_{ψ(3770)}^{\rm tot} = 28.6 \pm 1.2 \pm 0.2$ MeV, $Γ_{ψ(3770)}^{ee} = 279 \pm 11 \pm 13$ eV and $B[ψ(3770)\to e^+e^-]=(0.98\pm 0.04\pm 0.04)\times 10^{-5}$, respectively, which result in the observed cross section $σ^{\rm obs}[e^+e^-\to ψ(3770)]=7.25\pm 0.27 \pm 0.34$ nb at $\sqrt{s}=3772.4$ MeV. We have also measured $R_{\rm uds}=2.121\pm 0.023 \pm 0.084$ for the continuum light hadron production in the region from 3.650 to 3.872 GeV.

hep-ex↗

arXiv2006

Measurements of the braching fractions for psi(3770)--> D0D0-bar,D+D-,DD-bar$ and the resonance parameters of psi(3770) and psi(2S)

We report measurements of the branching fractions for $ψ(3770)\to D^0 \bar D^0, D^+D^-, D\bar D$ and resonance parameters of $ψ(3770)$ and $ψ(2S)$. By analyzing the line-shapes of the cross sections for inclusive hadron, $D^0 \bar D^0$ and $D^+D^-$ event production in the range from 3.660 GeV to 3.872 GeV covering both $ψ(2S)$ and $ψ(3770)$ resonances, we extract the branching fractions for $ψ(3770)$ decay into $D^0\bar D^0 {\rm and} D^+D^-$ respectively to be $B(ψ(3770)\to D^0 \bar D^0)=(46.7 \pm 4.7 \pm 2.3)%$ and $B(ψ(3770)\to D^+ D^-)=(36.9 \pm 3.7 \pm 2.8)%$, which give $B(ψ(3770)\to D \bar D)=(83.6 \pm 7.3 \pm 4.2)%$ and non-$D\bar D$ branching fraction of $ψ(3770)$ to be $B(ψ(3770)\to non-D \bar D)=(16.4 \pm 7.3 \pm 4.2)%$. We meanwhile obtain the resonance parameters of $ψ(3770)$ and $ψ(2S)$ to be $M_{ψ(3770)}=3772.2 \pm 0.7 \pm 0.3$ MeV, $Γ^{\rm tot}_{ψ(3770)}=26.9 \pm 2.4 \pm 0.3$ MeV and $Γ^{ee}_{ψ(3770)}=251 \pm 26 \pm 11$ eV; $M_{ψ(2S)}=3685.5 \pm 0.0 \pm 0.3$ MeV, $Γ^{\rm tot}_{ψ(2S)}=331 \pm 58 \pm 2$ keV and $Γ^{ee}_{ψ(2S)}=2.330 \pm 0.036 \pm 0.110$ keV; as well as the $R$ value for the light hadron production directly through one photon annihilation to be $R_{uds}=2.262\pm 0.054\pm 0.109$ in this energy region.

hep-ex↗

arXiv2006

Measurements of the cross sections for $e^+e^- \to {\rm hadrons}$ at 3.650, 3.6648, 3.773 GeV and the branching fraction for $ψ(3770)\to {\rm non-}D\bar D$

Using the BES-II detector at the BEPC Collider, we measured the lowest order cross sections and the $R$ values ($R=σ^0_{e^+e^- \to {\rm hadrons}}/σ^0_{e^+e^- \to μ^+μ^-}$) for inclusive hadronic event production at the center-of-mass energies of 3.650 GeV, 3.6648 GeV and 3.773 GeV. The results lead to $\bar R_{uds}=2.224\pm 0.019\pm 0.089$ which is the average of these measured at 3.650 GeV and 3.6648 GeV, and $R=3.793\pm 0.037 \pm 0.190$ at $\sqrt{s}=3.773$ GeV. We determined the lowest order cross section for $ψ(3770)$ production to be $σ^{\rm B}_{ψ(3770)} = (9.575\pm 0.256 \pm 0.813)~{\rm nb}$ at 3.773 GeV, the branching fractions for $ψ(3770)$ decays to be $BF(ψ(3770) \to D^0\bar D^0)=(48.9 \pm 1.2 \pm 3.8)%$, $BF(ψ(3770) \to D^+ D^-)=(35.0 \pm 1.1 \pm 3.3)%$ and $BF(ψ(3770) \to D\bar{D})=(83.9 \pm 1.6 \pm 5.7)%$, which result in the total non-$D\bar D$ branching fraction of $ψ(3770)$ decay to be $BF(ψ(3770) \to {\rm non}-D\bar D)=(16.1 \pm 1.6 \pm 5.7)%$.

hep-ex↗