Refine
Year of publication
Language
- English (592)
Has Fulltext
- yes (592)
Is part of the Bibliography
- no (592)
Keywords
- BESIII (20)
- e +-e − Experiments (20)
- Branching fraction (15)
- Particle and Resonance Production (9)
- Charm Physics (6)
- Quarkonium (6)
- Spectroscopy (6)
- Hadronic decays (5)
- QCD (5)
- Branching fractions (4)
Institute
- Physik (589)
- Frankfurt Institute for Advanced Studies (FIAS) (1)
- Informatik (1)
- Medizin (1)
Using 𝑒+𝑒−→Λ+𝑐¯Λ−𝑐 production from a 567 pb−1 data sample collected by BESIII at 4.6 GeV, a full angular analysis is carried out simultaneously on the four decay modes of Λ+𝑐→𝑝𝐾0𝑆, Λ𝜋+, Σ+𝜋0, and Σ0𝜋+. For the first time, the Λ+𝑐 transverse polarization is studied in unpolarized 𝑒+𝑒− collisions, where a nonzero effect is observed with a statistical significance of 2.1𝜎. The decay asymmetry parameters of the Λ+𝑐 weak hadronic decays into 𝑝𝐾0𝑆, Λ𝜋+, Σ+𝜋0 and Σ0𝜋+ are measured to be 0.18±0.43(stat)±0.14(syst), −0.80±0.11(stat)±0.02(syst), −0.57±0.10(stat)±0.07(syst), and −0.73±0.17(stat)±0.07(syst), respectively. In comparison with previous results, the measurements for the Λ𝜋+ and Σ+𝜋0 modes are consistent but with improved precision, while the parameters for the 𝑝𝐾0𝑆 and Σ0𝜋+ modes are measured for the first time.
The first amplitude analysis of the decay D+s→K−K+π+π0 is presented using the data samples, corresponding to an integrated luminosity of 6.32 fb−1, collected with the BESIII detector at e+e− center-of-mass energies between 4.178 and 4.226 GeV. More than 3000 events selected with a purity of 97.5\% are used to perform the amplitude analysis, and nine components are found necessary to describe the data. Relative fractions and phases of the intermediate decays are determined. With the detection efficiency estimated by the results of the amplitude analysis, the branching fraction of D+s→K−K+π+π0 decay is measured to be (5.42±0.10stat.±0.17syst.)%.
We present the first amplitude analysis of the decay D+s→K−K+π+π0 using data samples of 6.32 fb−1 recorded with the BESIII detector between 4.178 and 4.226 GeV. More than 3000 events selected with a purity of 97.5\% are used to perform the amplitude analysis, and nine components are found necessary to describe the data. Relative fractions and phases of the intermediate decays are determined. With the detection efficiency determined by the results of the amplitude analysis, we measure the branching fraction of D+s→K−K+π+π0 decay to be (5.42±0.10stat.±0.17syst.)%.
Search for the reaction channel e⁺e⁻ → ηcηπ⁺π⁻ at center-of-mass energies from 4.23 to 4.60 GeV
(2021)
Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider, we search for the process 𝑒+𝑒−→𝜂𝑐𝜂𝜋+𝜋−. The search is performed using five large datasets recorded at center-of-mass energies of 4.23, 4.26, 4.36, 4.42, and 4.60 GeV. The 𝜂𝑐 meson is reconstructed in 16 exclusive decay modes. No signal is observed in the 𝜂𝑐 mass region at any center-of-mass energy. The upper limits on the reaction cross sections are determined to be 6.2, 10.8, 27.6, 22.6 and 23.7 pb at the 90% confidence level at the center-of-mass energies listed above.
We report on an analysis of the decay J/ψ→γπ0η′ using a sample of (1310.6±7.0)× 106 J/ψ events collected with the BESIII detector. We search for the CP-violating process ηc→π0η′ and a dark gauge boson U′ in J/ψ→U′η′, U′→γπ0, π0→γγ. No evidence of an ηc signal is observed in the π0η′ invariant-mass spectrum and the upper limit of the branching fraction is determined to be 7.2× 10−5 at the 90\% confidence level. We also find no evidence of U′ production and set upper limits at the 90\% confidence level on the product branching fraction B(J/ψ→U′η′)×B(U′→π0γ) in the range between (0.8−6.5)×10−7 for 0.2 ≤mU′≤2.1GeV/c2. In addition, we study the process J/ψ→ωη′ with ω→γπ0. The branching fraction of J/ψ→ωη′ is found to be (1.87±0.09±0.12)×10−4, where the first uncertainty is statistical and the second is systematic, with a precision that is improved by a factor of 1.4 over the previously published BESIII measurement.
A partial-wave analysis of the decay 𝐽/𝜓→𝐾+𝐾−𝜋0 has been made using (223.7±1.4)×106 𝐽/𝜓 events collected with the BESIII detector in 2009. The analysis, which is performed within the isobar-model approach, reveals contributions from 𝐾*2(1430)±, 𝐾*2(1980)± and 𝐾*4(2045)± decaying to 𝐾±𝜋0. The two latter states are observed in 𝐽/𝜓 decays for the first time. Two resonance signals decaying to 𝐾+𝐾− are also observed. These contributions cannot be reliably identified and their possible interpretations are discussed. The measured branching fraction 𝐵(𝐽/𝜓→𝐾+𝐾−𝜋0) of (2.88±0.01±0.12)×10−3 is more precise than previous results. Branching fractions for the reported contributions are presented as well. The results of the partial-wave analysis differ significantly from those previously obtained by BESII and BABAR.
We measure the Born cross sections of the process 𝑒+𝑒−→𝐾+𝐾−𝐾+𝐾− at center-of-mass (c.m.) energies, √𝑠, between 2.100 and 3.080 GeV. The data were collected using the BESIII detector at the BEPCII collider. An enhancement at √𝑠=2.232 GeV is observed, very close to the 𝑒+𝑒−→Λ¯Λ production threshold. A similar enhancement at the same c.m. energy is observed in the 𝑒+𝑒−→𝜙𝐾+𝐾− cross section. The energy dependence of the 𝐾+𝐾−𝐾+𝐾− and 𝜙𝐾+𝐾− cross sections differs significantly from that of 𝑒+𝑒−→𝜙𝜋+𝜋−.
By using 6.32 fb−1 of data collected with the BESIII detector at center-of-mass energies between 4.178 and 4.226 GeV, we perform an amplitude analysis of the decay D+s ! K0S + 0 and determine the relative fractions and phase differences of different intermediate processes, which include K0S (770)+, K0S (1450)+, K (892)0 +, K (892)+ 0, and K (1410)0 +. With the detection efficiency based on the amplitude analysis results, the absolute branching fraction is measured to be B(D+s ! K0S + 0) = (5.43 ± 0.30stat ± 0.15syst) × 10−3.
By analyzing a 2.93~fb−1 data sample of e+e− collisions, recorded at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the BEPCII collider, we have searched for the semileptonic D+ transition into the axial-vector meson K¯1(1270)0. The D+→K¯1(1270)0e+νe decay is observed for the first time with a statistical significance greater than 10σ. Its decay branching fraction is determined to be B[D+→K¯1(1270)0e+νe]=(2.30±0.26±0.18±0.25)×10−3, where the first and second uncertainties are statistical and systematic, respectively, and the third originates from the input branching fraction of K¯1(1270)0→K−π+π0.
Using a sample of (448.1±2.9)×106 ψ(3686) events collected with the BESIII detector, we perform the first partial wave analysis of ψ(3686)→K+K−η. In addition to the well established states, ϕ(1020), ϕ(1680), and K∗3(1780), contributions from X(1750), ρ(2150), ρ3(2250), and K∗2(1980) are also observed. The X(1750) state is determined to be a 1−− resonance. The simultaneous observation of the ϕ(1680) and X(1750) indicates that the X(1750), with previous observations in photoproduction, is distinct from the ϕ(1680). The masses, widths, branching fractions of ψ(3686)→K+K−η and the intermediate resonances are also measured.
