Refine
Year of publication
Language
- English (373)
Has Fulltext
- yes (373)
Is part of the Bibliography
- no (373)
Keywords
- BESIII (18)
- e +-e − Experiments (15)
- Branching fraction (11)
- Particle and Resonance Production (8)
- Charm Physics (6)
- Spectroscopy (6)
- Hadronic decays (5)
- Quarkonium (5)
- Branching fractions (4)
- Charmonium (4)
Institute
- Physik (371)
We report the measurement of the cross sections for e+e−→hadrons at center-of-mass (c.m.) energies from 3.645 to 3.871 GeV. We observe a new resonance R(3810) in the cross sections for the first time, and observe the R(3760) resonance with high significance in the cross sections. The R(3810) has a mass of (3804.5±0.9±0.9) ~MeV/c2, a total width of (5.4±3.5±3.2)~MeV, and an electronic partial width of (19.4±7.4±12.1)~eV. Its significance is 7.7σ. The R(3810) could be interpreted as a hadro-charmonium resonance predicted by Quantum Chromodynamics (QCD). In addition, we measure the mass (3751.9±3.8±2.8) ~MeV/c2, the total width (32.8±5.8±8.7)~MeV, and the electronic partial width (184±75±86)~eV with improved precision for the R(3760). Furthermore, for the R(3780) we measure the mass (3778.7±0.5±0.3) ~MeV/c2 and total width (20.3±0.8±1.7)~MeV with improved precision, and the electronic partial width (265±69±83)~eV. The R(3780) can be interpreted as the 13D1 state of charmonium. Its mass and total width differ significantly from the corresponding fitted values given by the Particle Data Group in 2022 by 7.1 and 3.2 times the uncertainties for ψ(3770), respectively. ψ(3770) has been interpreted as the 13D1 state for 45 years.
We measured the Born cross sections for the process e+e− → ωη′ at 22 center-of-mass energies from 2.000 to 3.080 GeV with the BESIII detector at the BEPCII collider. We observed a resonant structure with a statistical significance of 9.6σ. A Breit-Wigner fit determines its mass to be MR = (2153 ± 30 ± 31) MeV/c2 and its width to be ΓR = (167 ± 77 ± 7) MeV, where the first uncertainties are statistical and the second are systematic.
Measurement of the e+e−→π+π− cross section between 600 and 900 MeV using initial state radiation
(2016)
We extract the e+e− →π+π− cross section in the energy range between 600 and 900 MeV, exploiting the method of initial state radiation. A data set with an integrated luminosity of 2.93 fb−1 taken at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider is used. The cross section is measured with a systematic uncertainty of 0.9%. We extract the pion form factor |Fπ|2 as well as the contribution of the measured cross section to the leading-order hadronic vacuum polarization contribution to (g−2)μ. We find this value to be aππ,LO μ (600–900 MeV) = (368.2 ±2.5stat±3.3sys) ·10−10, which is between the corresponding values using the BaBar or KLOE data.