Refine
Year of publication
Document Type
- Article (153)
- Preprint (90)
- Conference Proceeding (2)
- Working Paper (1)
Language
- English (246)
Has Fulltext
- yes (246)
Is part of the Bibliography
- no (246)
Keywords
- BESIII (12)
- Branching fraction (8)
- e +-e − Experiments (6)
- Hadronic decays (4)
- Lepton colliders (4)
- Particle and Resonance Production (4)
- Branching fractions (3)
- Charmed mesons (3)
- Electroweak interaction (3)
- Spectroscopy (3)
- Bhabha (2)
- Charm Physics (2)
- Charm physics (2)
- Charmonium (2)
- Cross section (2)
- Electroweak Interaction (2)
- Exotics (2)
- Leptonic, semileptonic & radiative decays (2)
- Particle decays (2)
- Quarkonium (2)
- e+-e− Experiments (2)
- 140Ce (1)
- Absolute branching fraction (1)
- Adaptive dynamics (1)
- Angular distribution (1)
- Annihilation (1)
- BESIII detector (1)
- Biodiversity (1)
- CP violation (1)
- Conservation biology (1)
- Couch tracking (1)
- Cross section measurements (1)
- D0 and D+ mesons (1)
- Dalitz decay (1)
- Dark photon (1)
- Dark sector (1)
- Devic disease (1)
- Devic syndrome (1)
- Diagnostic markers (1)
- Diversity in trait space (1)
- Dormancy (1)
- D⁰ meson (1)
- Electromagnetic amplitude (1)
- Electromagnetic form factor (1)
- Electromagnetic form factors (1)
- Electromagnetic transitions (1)
- Electron-pion identification (1)
- Environmental impact (1)
- Evolutionary branching (1)
- Experimental models of disease (1)
- Experimental nuclear physics (1)
- Experimental particle physics (1)
- Fibre/foam sandwich radiator (1)
- Flavor changing neutral currents (1)
- Flavor symmetries (1)
- Flavour Physics (1)
- Form factors (1)
- Gimbaled tracking (1)
- Hadrons (1)
- Hyperons (1)
- Inclusive branching fraction (1)
- Initial state radiation (1)
- Invisible decays (1)
- Ionisation energy loss (1)
- K0S (1)
- MACS (1)
- MLC tracking (1)
- Models & methods for nuclear reactions (1)
- Multi-wire proportional drift chamber (1)
- NMO-IgG (1)
- Neural network (1)
- Neuromyelitis optica (1)
- Neutrinos (1)
- Neutron physics (1)
- Nuclear reactions (1)
- Organ motion (1)
- Particle and resonance production (1)
- Particle phenomena (1)
- Phase (1)
- Polarization (1)
- Polymorphic evolution sequence (1)
- Proton (1)
- Quantum chromodynamics (1)
- R value (1)
- Radiative capture (1)
- Rare decays (1)
- Resonance reactions (1)
- Respiratory signs and symptoms (1)
- Robotic tracking (1)
- Semi-leptonic decays (1)
- Strong amplitude (1)
- Sympatric speciation (1)
- TR (1)
- Techniques Electromagnetic calorimeters (1)
- Tracking (1)
- Transition radiation detector (1)
- Translational research (1)
- Trauma (1)
- Trigger (1)
- Triple quarkonia (1)
- W-exchange (1)
- Xenon-based gas mixture (1)
- Y (4260) (1)
- Y states (1)
- additive manufacturing (1)
- animal behavior states (1)
- aquaporin-4 (AQP4) antibody (1)
- automated monitoring (1)
- cancer cell dormancy (1)
- capture (1)
- center-of-mass energy (1)
- cerebrospinal fluid (1)
- cerium (1)
- charmonium-like states (1)
- clinical features (1)
- convolutional neural networks (1)
- cross-section (1)
- dE/dx (1)
- decay (1)
- deep learning tools (1)
- dimuon (1)
- diphoton (1)
- e+e − annihilation (1)
- e+e⁻ − Experiments (1)
- e+e− Experiments (1)
- e+e− annihilation (1)
- ecology of savannah animals (1)
- energy-dispersive x-ray spectroscopy (1)
- epidemiology (1)
- fecal microbiota transfer (1)
- graft-vs-host disease (1)
- hadronic events (1)
- human allogeneic hematopoietic cell transplantation (1)
- human intestinal microbiota (1)
- image classification (1)
- inclusive J/ψ decays (1)
- individual-based models (1)
- light-induced polymerization (1)
- longitudinally extensive transverse myelitis (1)
- luminosity (1)
- magnetic resonance imaging (1)
- multi-drug treatment (1)
- n_TOF (1)
- neutron (1)
- nucleosynthesis (1)
- number of J/ψ events (1)
- quantum electrodynamics test (1)
- recurrent optic neuritis (1)
- resistance mutation (1)
- s-process (1)
- self-initiated photografting and photopolymerization (1)
- stochastic population dynamics (1)
- storage rings (1)
- strong Coulomb field (1)
- surface modification (1)
- surface-initiated polymerization (1)
- therapy evasion (1)
- treatment protocol design (1)
- treatment success (1)
- trigger efficiency (1)
- Λ+c baryon (1)
- Λc⁺ (1)
- Σ hyperon (1)
- ψ(3686) (1)
Institute
Based on 4.5 fb−1 of e+e− collision data accumulated at center-of-mass energies between 4599.53 MeV and 4698.82 MeV with the BESIII detector, the decay Λ+c→nK0Sπ+π0 is observed for the first time with a significance of 9.2σ. The branching fraction is measured to be (0.85±0.13±0.03)%, where the first uncertainty is statistical and the second systematic, which differs from the theoretical prediction based on isospin by 4.4σ. This indicates that there may be resonant contributions or some unknown dynamics in this decay.
The Born cross sections for the process e+e−→η′π+π− 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 6.3σ and a mass and width of M=(2108±46±25)~MeV/c2 and Γ=(138±36±30)~MeV, where the uncertainties are statistical and systematic, respectively. These measured resonance parameters agree with the measurements of BABAR in e+e−→η′π+π− and BESIII in e+e−→ωπ0 within two standard deviations.
Using 2.93 fb−1 of e+e− collision data taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, the observation of the D0→K1(1270)−e+νe semileptonic decay is presented. The statistical significance of the decay D0→K1(1270)−e+νe is greater than 10σ. The branching fraction of D0→K1(1270)−e+νe is measured to be (1.09±0.13+0.09−0.16±0.12)×10−3. Here, the first uncertainty is statistical, the second is systematic, and the third originates from the assumed branching fraction of K1(1270)−→K−π+π−. The fraction of longitudinal polarization in D0→K1(1270)−e+νe is determined for the first time to be 0.50±0.19stat±0.08syst.
Observation of resonance structures in e⁺e⁻ → π⁺π⁻ψ₂(3823) and mass measurement of ψ₂(3823)
(2022)
Using a data sample corresponding to an integrated luminosity of 11.3 fb−1 collected at center-of-mass energies from 4.23 to 4.70 GeV with the BESIII detector, we measure the product of the 𝑒+𝑒−→𝜋+𝜋−𝜓2(3823) cross section and the branching fraction ℬ[𝜓2(3823)→𝛾𝜒𝑐1]. For the first time, resonance structure is observed in the cross section line shape of 𝑒+𝑒−→𝜋+𝜋−𝜓2(3823) with significances exceeding 5𝜎. A fit to data with two coherent Breit-Wigner resonances modeling the √𝑠-dependent cross section yields 𝑀(𝑅1)=4406.9±17.2±4.5 MeV/𝑐2, Γ(𝑅1)=128.1±37.2±2.3 MeV, and 𝑀(𝑅2)=4647.9±8.6±0.8 MeV/𝑐2, Γ(𝑅2)=33.1±18.6±4.1 MeV. Though weakly disfavored by the data, a single resonance with 𝑀(𝑅)=4417.5±26.2±3.5 MeV/𝑐2, Γ(𝑅)=245±48±13 MeV is also possible to interpret data. This observation deepens our understanding of the nature of the vector charmoniumlike states. The mass of the 𝜓2(3823) state is measured as (3823.12±0.43±0.13) MeV/𝑐2, which is the most precise measurement to date.
Using 2.93 fb−1 of 𝑒+𝑒− collision data taken at a center-of-mass energy of 3.773 GeV by the BESIII detector at the BEPCII, we measure the branching fractions of the singly Cabibbo-suppressed decays 𝐷→𝜔𝜋𝜋 to be ℬ(𝐷0→𝜔𝜋+𝜋−)=(1.33±0.16±0.12)×10−3 and ℬ(𝐷+→𝜔𝜋+𝜋0)=(3.87±0.83±0.25)×10−3, where the first uncertainties are statistical and the second ones systematic. The statistical significances are 12.9𝜎 and 7.7𝜎, respectively. The precision of ℬ(𝐷0→𝜔𝜋+𝜋−) is improved by a factor of 2.1 over prior measurements, and ℬ(𝐷+→𝜔𝜋+𝜋0) is measured for the first time. No significant signal for 𝐷0→𝜔𝜋0𝜋0 is observed, and the upper limit on the branching fraction is ℬ(𝐷0→𝜔𝜋0𝜋0)<1.10×10−3 at the 90% confidence level. The branching fractions of 𝐷→𝜂𝜋𝜋 are also measured and consistent with existing results.
Using 2.93 fb−1 of 𝑒+𝑒− collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector, we report the first measurements of the absolute branching fractions of 14 hadronic 𝐷0(+) decays to exclusive final states with an 𝜂, e.g., 𝐷0→𝐾−𝜋+𝜂, 𝐾0𝑆𝜋0𝜂, 𝐾+𝐾−𝜂, 𝐾0𝑆𝐾0𝑆𝜂, 𝐾−𝜋+𝜋0𝜂, 𝐾0𝑆𝜋+𝜋−𝜂, 𝐾0𝑆𝜋0𝜋0𝜂, and 𝜋+𝜋−𝜋0𝜂; 𝐷+→𝐾0𝑆𝜋+𝜂, 𝐾0𝑆𝐾+𝜂, 𝐾−𝜋+𝜋+𝜂, 𝐾0𝑆𝜋+𝜋0𝜂, 𝜋+𝜋+𝜋−𝜂, and 𝜋+𝜋0𝜋0𝜂. Among these decays, the 𝐷0→𝐾−𝜋+𝜂 and 𝐷+→𝐾0 𝑆𝜋+𝜂 decays have the largest branching fractions, which are ℬ(𝐷0→𝐾−𝜋+𝜂) = (1.853±0.025stat±0.031syst)% and ℬ(𝐷+→𝐾0𝑆𝜋+𝜂) = (1.309±0.037stat±0.031syst)%, respectively. The charge-parity asymmetries for the six decays with highest event yields are determined, and no statistically significant charge-parity violation is found.
Using about 23 fb−1 of data collected with the BESIII detector operating at the BEPCII storage ring, a precise measurement of the e+e−→π+π−J/ψ Born cross section is performed at center-of-mass energies from 3.7730 to 4.7008 GeV. Two structures, identified as the Y(4220) and the Y(4320) states, are observed in the energy-dependent cross section with a significance larger than 10σ. The masses and widths of the two structures are determined to be (M,Γ) = (4221.4±1.5±2.0 MeV/c2, 41.8±2.9±2.7 MeV) and (M,Γ) = (4298±12±26 MeV/c2, 127±17±10 MeV), respectively. A small enhancement around 4.5 GeV with a significance about 3σ, compatible with the ψ(4415), might also indicate the presence of an additional resonance in the spectrum. The inclusion of this additional contribution in the fit to the cross section affects the resonance parameters of the Y(4320) state.
During the 2016-17 and 2018-19 running periods, the BESIII experiment collected 7.5~fb−1 of e+e− collision data at center-of-mass energies ranging from 4.13 to 4.44 GeV. These data samples are primarily used for the study of excited charmonium and charmoniumlike states. By analyzing the di-muon process e+e−→(γISR/FSR)μ+μ−, we measure the center-of-mass energies of the data samples with a precision of 0.6 MeV. Through a run-by-run study, we find that the center-of-mass energies were stable throughout most of the data-taking period.
The decays of χc2→K+K−π0, KSK±π∓ and π+π−π0 are studied with the ψ(3686) data samples collected with the Beijing Spectrometer (BESIII). For the first time, the branching fractions of χc2→K∗K¯¯¯¯¯, χc2→a±2(1320)π∓/a02(1320)π0 and χc2→ρ(770)±π∓ are measured. Here K∗K¯¯¯¯¯ denotes both K∗±K∓ and K∗0K¯¯¯¯¯0+c.c., and K∗ denotes the resonances K∗(892), K∗2(1430) and K∗3(1780). The observations indicate a strong violation of the helicity selection rule in χc2 decays into vector and pseudoscalar meson pairs. The measured branching fractions of χc2→K∗(892)K¯¯¯¯¯ are more than 10 times larger than the upper limit of χc2→ρ(770)±π∓, which is so far the first direct observation of a significant U-spin symmetry breaking effect in charmonium decays.
Using a sample of 448.1×106 ψ(2S) events collected with the BESIII detector, we perform a study of the decay J/ψ→K+K− via ψ(2S)→π+π−J/ψ.
The branching fraction of J/ψ→K+K− is determined to be BK+K−=(3.072±0.023(stat.)±0.050(syst.))×10−4, which is consistent with previous measurements but with significantly improved precision.
Based on 4.5 fb−1 of e+e− collision data accumulated at center-of-mass energies between 4599.53 MeV and 4698.82 MeV with the BESIII detector, the decay Λ+c→nK0Sπ+π0 is observed for the first time with a significance of 9.2σ. The branching fraction is measured to be (0.85±0.13±0.03)%, where the first uncertainty is statistical and the second systematic, which differs from the theoretical prediction based on isospin by 4.4σ. This indicates that there may be resonant contributions or some unknown dynamics in this decay.
Using 2.93 fb−1 of e+e− collision data collected with the BESIII detector at the center-of-mass energy 3.773 GeV, we perform the first amplitude analysis of the decay D+ → π+π0π0 and determine the relative magnitudes and phases of different intermediate processes. The absolute branching fraction of D+ → π+π0π0 is measured to be (2.888 ± 0.058stat. ± 0.069syst.)%. The dominant intermediate processes are D+ → a1(1260)+(→ ρ+π0) and D+ → *0ρ+, with branching fractions of (8.66 ± 1.04stat. ± 1.39syst.) × 10−3 and (9.70 ± 0.81stat. ± 0.53syst.) × 10−3, respectively.
Using a low background data sample of 9.7×105 𝐽/𝜓→𝛾𝜂′, 𝜂′→𝛾𝜋+𝜋− events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the BESIII detector at BEPCII, the decay dynamics of 𝜂′→𝛾𝜋+𝜋− are studied with both model-dependent and model-independent approaches. The contributions of 𝜔 and the 𝜌(770)−𝜔 interference are observed for the first time in the decays 𝜂′→𝛾𝜋+𝜋− in both approaches. Additionally, a contribution from the box anomaly or the 𝜌(1450) resonance is required in the model-dependent approach, while the process specific part of the decay amplitude is determined in the model-independent approach.
We report the first measurements of absolute branching fractions for the W -exchange-only processes + c → 0K + and + c → (1530)0K + with the double-tag technique, by analyzing an e+e− collision data sample, that corresponds to an integrated luminosity of 567 pb−1 collected at a center-of-mass energy of 4.6 GeV by the BESIII detector. The branching fractions are measured to be B(+c → 0K +) = (5.90 ± 0.86 ± 0.39) × 10−3 and B(+c → (1530)0K +) = (5.02 ± 0.99 ± 0.31) × 10−3, where the first uncertainties are statistical and the second systematic. Our results are more precise than the previous relative measurements.
Using a data sample corresponding to an integrated luminosity of 2.93 fb−1 collected at a center-of-mass energy s√=3.773 GeV by the BESIII detector, the decay D0→ωϕ is observed for the first time. The branching fraction is measured to be (6.48±0.96±0.38)×10−4 with a significance of 6.3σ, where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the ϕ and ω mesons from the D0→ωϕ decay are transversely polarized.
By analyzing (27.12±0.14)×108 ψ(3686) events accumulated with the BESIII detector, the decay ηc(2S)→K+K−η is observed for the first time with a significance of 6.2σ after considering systematic uncertainties. The product of the branching fractions of ψ(3686)→γηc(2S) and ηc(2S)→K+K−η is measured to be B(ψ(3686)→γηc(2S))×B(ηc(2S)→K+K−η)=(2.39±0.32±0.34)×10−6, where the first uncertainty is statistical, and the second one is systematic. The branching fraction of ηc(2S)→K+K−η is determined to be B(ηc(2S)→K+K−η)=(3.42±0.46±0.48±2.44)×10−3, where the third uncertainty is due to the branching fraction of ψ(3686)→γηc(2S). Using a recent BESIII measurement of B(ηc(2S)→K+K−π0), we also determine the ratio between the branching fractions of ηc(2S)→K+K−η and ηc(2S)→K+K−π0 to be 1.49±0.22±0.25, which is consistent with the previous result of BaBar at a comparable precision level.
Search for X(3872)→π⁰π⁰χc₁,₂
(2024)
Using 10.1 fb−1 of e+e− collision data collected by the BESIII detector with center-of-mass energies between 4.15 GeV and 4.30 GeV, we search for the decays X(3872)→π0π0χc1,2, where the X(3872) is produced in e+e−→γX(3872). No evidence above 3σ is found for either decay. Upper limits at the 90% C.L. on the branching fractions of X(3872)→π0π0χc1,2 normalized to the branching fraction of X(3872)→π+π−J/ψ are set to be B(X(3872)→π0π0χc1)/B(X(3872)→π+π−J/ψ)<1.1 and B(X(3872)→π0π0χc2)/B(X(3872)→π+π−J/ψ)<0.5, taking into account both statistical and systematic uncertainties.
Evidence for the singly Cabibbo suppressed decay Λ+c→pπ0 is reported for the first time with a statistical significance of 3.7σ based on 6.0 fb−1 of e+e− collision data collected at center-of-mass energies between 4.600 and 4.843 GeV with the BESIII detector at the BEPCII collider. The absolute branching fraction of Λ+c→pπ0 is measured to be (1.56+0.72−0.58±0.20)×10−4. Combining with the branching fraction of Λ+c→nπ+, (6.6±1.3)×10−4, the ratio of the branching fractions of Λ+c→nπ+ and Λ+c→pπ0 is calculated to be 3.2+2.2−1.2. As an important input for the theoretical models describing the decay mechanisms of charmed baryons, our result indicates that the non-factorizable contributions play an essential role and their interference with the factorizable contributions should not be significant. In addition, the absolute branching fraction of Λ+c→pη is measured to be (1.63±0.31stat±0.11syst)×10−3.
Using data samples collected with the BESIII detector at the BEPCII collider at six center-of-mass energies between 4.008 and 4.600 GeV, we observe the processes e+e− → φφω and e+e− → φφφ. The Born cross sections are measured and the ratio of the cross sections σ(e+e− → φφω)/σ(e+e− → φφφ) is estimated to be 1.75 ± 0.22 ± 0.19 averaged over six energy points, where the first uncertainty is statistical and the second is systematic. The results represent first measurements of these interactions.
The Born cross sections for the process e+e−→ωη′ are measured at 22 center-of-mass energies from 2.000 to 3.080 GeV using data collected with the BESIII detector at the BEPCII collider. A resonant structure is observed 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.