Refine
Year of publication
Document Type
- Article (521)
- Preprint (402)
- Working Paper (1)
Language
- English (924)
Has Fulltext
- yes (924)
Is part of the Bibliography
- no (924)
Keywords
- BESIII (20)
- e +-e − Experiments (17)
- Branching fraction (12)
- Particle and Resonance Production (9)
- Quarkonium (9)
- Charm Physics (6)
- Hadron-Hadron Scattering (6)
- LHC (6)
- Spectroscopy (6)
- Hadronic decays (5)
Institute
- Physik (810)
- Frankfurt Institute for Advanced Studies (FIAS) (327)
- Informatik (215)
- Informatik und Mathematik (3)
- Biochemie und Chemie (1)
- Center for Financial Studies (CFS) (1)
- House of Finance (HoF) (1)
- Medizin (1)
- Sustainable Architecture for Finance in Europe (SAFE) (1)
- Wirtschaftswissenschaften (1)
Using 2.93 fb−1 of e+e− collision data collected with the BESIII detector at the center-of-mass energy of 3.773 GeV, we investigate the semileptonic decays D+→π+π−ℓ+νℓ (ℓ=e and μ). The D+→f0(500)μ+νμ decay is observed for the first time. By analyzing simultaneously the differential decay rates of D+→f0(500)μ+νμ and D+→f0(500)e+νe in different ℓ+νℓ four-momentum transfer intervals, the product of the relevant hadronic form factor ff0+(0) and the magnitude of the c→d Cabibbo-Kobayashi-Maskawa matrix element |Vcd| is determined to be ff0+(0)|Vcd|=0.0787±0.0060stat±0.0033syst for the first time. With the input of |Vcd| from the global fit in the standard model, we determine ff0+(0)=0.350±0.027stat±0.015syst. The absolute branching fractions of D+→f0(500)(π+π−)μ+νμ and D+→ρ0(π+π−)μ+νμ are determined as (0.72±0.13stat±0.10syst)×10−3 and (1.64±0.13stat±0.11syst)×10−3. Combining these results with those of previous BESIII measurements on their semielectronic counterparts from the same data sample, we test lepton flavor universality by measuring the branching fraction ratios BD+→ρ0μ+νμ/BD+→ρ0e+νe = 0.88±0.10 and BD+→f0(500)μ+νμ/BD+→f0(500)e+νe = 1.14±0.28, which are compatible with the standard model expectation.
Using 2.93 fb−1 of e+e− collision data collected with the BESIII detector at the center-of-mass energy of 3.773 GeV, we investigate the semileptonic decays D+→π+π−ℓ+νℓ (ℓ=e and μ). The D+→f0(500)μ+νμ decay is observed for the first time. By analyzing simultaneously the differential decay rates of D+→f0(500)μ+νμ and D+→f0(500)e+νe in different ℓ+νℓ four-momentum transfer intervals, the product of the relevant hadronic form factor ff0+(0) and the magnitude of the c→d Cabibbo-Kobayashi-Maskawa matrix element |Vcd| is determined to be ff0+(0)|Vcd|=0.0787±0.0060stat±0.0033syst for the first time. With the input of |Vcd| from the global fit in the standard model, we determine ff0+(0)=0.350±0.027stat±0.015syst. The absolute branching fractions of D+→f0(500)(π+π−)μ+νμ and D+→ρ0(π+π−)μ+νμ are determined as (0.72±0.13stat±0.10syst)×10−3 and (1.64±0.13stat±0.11syst)×10−3. Combining these results with those of previous BESIII measurements on their semielectronic counterparts from the same data sample, we test lepton flavor universality by measuring the branching fraction ratios BD+→ρ0μ+νμ/BD+→ρ0e+νe=0.88±0.10 and BD+→f0(500)μ+νμ/BD+→f0(500)e+νe = 1.14±0.28, which are compatible with the standard model expectation.
Using 7.93 fb−1 of e+e− collision data collected at the center-of-mass energy of 3.773 GeV with the BESIII detector, we measure the absolute branching fractions of D0→K−e+νe, D0→K−μ+νμ, D+→K¯0e+νe, and D+→K¯0μ+νμ to be (3.509±0.009stat.±0.013syst.)%, (3.408±0.011stat.±0.013syst.)%, (8.856±0.039stat.±0.078syst.)%, and (8.661±0.046stat.±0.080syst.)%, respectively. By performing a simultaneous fit to the partial decay rates of these four decays, the product of the hadronic form factor fK+(0) and the modulus of the c→s CKM matrix element |Vcs| is determined to be fK+(0)|Vcs|=0.7162±0.0011stat.±0.0012syst.. Taking the value of |Vcs|=0.97349±0.00016 from the standard model global fit or that of fK+(0)=0.7452±0.0031 from the LQCD calculation as input, we derive the results fK+(0)=0.7357±0.0011stat.±0.0012syst. and |Vcs|=0.9611±0.0015stat.±0.0016syst.±0.0040LQCD.
We perform the first investigation of the process e+e−→K+K−ψ(2S) and report its Born cross sections over a range of center-of-mass energies from 4.699 to 4.951~GeV. The measurements are carried out using several partial reconstruction techniques using data samples collected by the BESIII detector with a total integrated luminosity of 2.5~fb−1. We search for new tetraquark candidates Z±cs in the decays Z±cs→K±ψ(2S). No significant Z±cs signals are observed.
Using (2712.4±14.3)×106 ψ(3686) events collected with the BESIII detector operating at the BEPCII collider, we search for the hadronic transition hc→π+π−J/ψ via ψ(3686)→π0hc. No significant signal is observed. We set the most stringent upper limits to date on the branching fractions B(ψ(3686)→π0hc)×B(hc→π+π−J/ψ) and B(hc→π+π−J/ψ) at the 90% confidence level, which are determined to be 6.7×10−7 and 9.4×10−4, respectively.
The e+e−→D+sDs1(2536)− and e+e−→D+sD∗s2(2573)− processes are studied using data samples collected with the BESIII detector at center-of-mass energies from 4.530 to 4.946~GeV. The absolute branching fractions of Ds1(2536)−→D¯∗0K− and D∗s2(2573)−→D¯0K− are measured for the first time to be (35.9±4.8±3.5)% and (37.4±3.1±4.6)%, respectively. The measurements are in tension with predictions based on the assumption that the Ds1(2536) and D∗s2(2573) are dominated by a bare cs¯ component. The e+e−→D+sDs1(2536)− and e+e−→D+sD∗s2(2573)− cross sections are measured, and a resonant structure at around 4.6~GeV with a width of 50~MeV is observed for the first time with a statistical significance of 15σ in the e+e−→D+sD∗s2(2573)− process. It could be the Y(4626) found by the Belle collaboration in the D+sDs1(2536)− final state, since they have similar masses and widths. There is also evidence for a structure at around 4.75~GeV in both processes.
The CP-even fractions (F+) of the decays D0→π+π−π0 and D0→K+K−π0 are measured with a quantum-correlated ψ(3770)→DD¯ data sample collected by the BESIII experiment corresponding to an integrated luminosity of 7.93 fb−1. The results are Fπ+π−π0+=0.9406±0.0036±0.0021 and FK+K−π0+=0.631±0.014±0.011, where the first uncertainties are statistical and the second systematic. These measurements are consistent with the previous determinations, and the uncertainties for Fπ+π−π0+ and FK+K−π0+ are reduced by factors of 3.9 and 2.6, respectively. The reported results provide important inputs for the precise measurement of the angle γ of the Cabibbo-Kobayashi-Maskawa matrix and indirect CP violation in charm mixing.
In the effective field theory, the massless dark photon γ′ can only couple with the Standard Model particle through operators of dimension higher than four, thereby offering a high sensitivity to the new physics energy scale. Using 7.9 fb−1 of e+e− collision data collected at s√=3.773 GeV with the BESIII detector at the BEPCII collider, we measure the effective flavor-changing neutral current coupling of cuγ′ in D0→ωγ′ and D0→γγ′ processes to search for the massless dark photon. No significant signals are observed, and the upper limits at the 90% confidence level on the massless dark photon branching fraction are set to be 1.1×10−5 and 2.0×10−6 for D0→ωγ′ and D0→γγ′, respectively. These results provide the most stringent constraint on the new physics energy scale associated with cuγ′ coupling in the world, with the new physics energy scale related parameter |C|2+|C5|2<8.2×10−17 GeV−2 at the 90% confidence level, playing a unique role in the dark sector search with the charm sector.
Model-independent determination of the strong-phase difference between D⁰ and D̄⁰ → π⁺π⁻π⁺π⁻ decays
(2024)
Measurements of the strong-phase difference between D0 and D¯0→π+π−π+π− are performed in bins of phase space. The study exploits a sample of quantum-correlated DD¯ mesons collected by the BESIII experiment in e+e− collisions at a center-of-mass energy of 3.773~GeV, corresponding to an integrated luminosity of 2.93~fb−1. Here, D denotes a neutral charm meson in a superposition of flavor eigenstates. The reported results are valuable for measurements of the CP-violating phase γ (also denoted ϕ3) in B±→DK±, D→π+π−π+π− decays, and the binning schemes are designed to provide good statistical sensitivity to this parameter. The expected uncertainty on γ arising from the precision of the strong-phase measurements, when applied to very large samples of B-meson decays, is around 1.5∘ or 2∘, depending on the binning scheme. The binned strong-phase parameters are combined to give a value of F4π+=0.746±0.010±0.004 for the CP-even fraction of D0→π+π−π+π− decays, which is around 30\% more precise than the previous best measurement of this quantity.
The processes hc→γP(P=η′, η, π0)) are studied with a sample of (27.12±0.14)×108 ψ(3686) events collected by the BESIII detector at the BEPCII collider. The branching fractions of hc→γη′ and hc→γη are measured to be (1.40±0.11±0.04±0.10)×10−3 and (3.77±0.55±0.13±0.26)×10−4, respectively, where the first uncertainties are statistical, the second systematic, and the third from the branching fraction of ψ(3686)→π0hc. The ratio Rhc=B(hc→γη)B(hc→γη′) is calculated to be (27.0±4.4±1.0)%. The measurements are consistent with the previous results with improved precision by a factor of 2. The results are valuable for gaining a deeper understanding of η−η′ mixing, and its manifestation within quantum chromodynamics. No significant signal is found for the decay hc→γπ0, and an upper limit is placed on its branching fraction of B(hc→γπ0)<5.0×10−5, at the 90\% confidence level.
