S. J. Chen
A5043629936- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Computational Physics and Python Applications
- Cosmology and Gravitation Theories
- Medical Imaging Techniques and Applications
- Astrophysics and Cosmic Phenomena
- Distributed and Parallel Computing Systems
- Black Holes and Theoretical Physics
- Particle Accelerators and Free-Electron Lasers
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- advanced mathematical theories
- Nuclear physics research studies
- Advanced Data Storage Technologies
- Parkinson's Disease Mechanisms and Treatments
- Scientific Research and Philosophical Inquiry
- Superconducting Materials and Applications
- Neurobiology of Language and Bilingualism
- International Science and Diplomacy
- Birth, Development, and Health
- Big Data Technologies and Applications
Nanjing University
2016-2025
Institute of High Energy Physics
1998-2024
Institut de Recherche sur les Lois Fondamentales de l'Univers
2023-2024
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2023-2024
CEA Paris-Saclay
2023-2024
Second Affiliated Hospital of Nanchang University
2023-2024
Nanchang University
2023-2024
A. Alikhanyan National Laboratory
2024
East China University of Science and Technology
2024
The University of Adelaide
2018-2023
The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle ${\ensuremath{\theta}}_{13}$ with significance of 5.2 standard deviations. Antineutrinos from six 2.9 $\mathrm{G}{\mathrm{W}}_{\mathrm{th}}$ reactors were detected in antineutrino detectors deployed two near (flux-weighted baseline 470 m and 576 m) one far (1648 underground experimental halls. With $43\text{ }000\text{ }\text{ }\mathrm{ton}--\mathrm{G}{\mathrm{W}}_{\mathrm{th}}--\mathrm{day}$...
The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose underground liquid scintillator detector, was proposed with the determination of neutrino mass hierarchy as primary physics goal. It is also capable observing neutrinos from terrestrial and extra-terrestrial sources, including supernova burst neutrinos, diffuse background, geoneutrinos, atmospheric solar well exotic searches such nucleon decays, dark matter, sterile etc. We present motivations anticipated...
We study the process e+e−→(D∗¯D∗)±π∓ at a center-of-mass energy of 4.26 GeV using 827 pb−1 data sample obtained with BESIII detector Beijing Electron Positron Collider. Based on partial reconstruction technique, Born cross section is measured to be (137±9±15) pb. observe structure near (D∗¯D∗)± threshold in π∓ recoil mass spectrum, which we denote as Z±c(4025). The and width are (4026.3±2.6±3.7) MeV/c2 (24.8±5.6±7.7) MeV, respectively. Its production ratio...
A measurement of the energy dependence antineutrino disappearance at Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9 GW(th) reactors were detected with detectors deployed in two near (effective baselines 512 and 561 m) one far (1579 underground experimental halls. Using 217 days data, 41 589 (203 809 92 912) candidates hall (near halls). An improved oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) first direct ν¯(e) mass-squared...
We report an improved measurement of the neutrino mixing angle $\theta_{13}$ from Daya Bay Reactor Neutrino Experiment. exclude a zero value for $\sin^22\theta_{13}$ with significance 7.7 standard deviations. Electron antineutrinos six reactors 2.9 GW$_{\rm th}$ were detected in antineutrino detectors deployed two near (flux-weighted baselines 470 m and 576 m) one far (1648 underground experimental halls. Using 139 days data, 28909 (205308) electron candidates at hall (near halls). The ratio...
The beta decay of the lightest charmed baryon $${\Lambda }_{c}^{+}$$ provides unique insights into fundamental mechanism strong and electro-weak interactions, serving as a testbed for investigating non-perturbative quantum chromodynamics constraining Cabibbo-Kobayashi-Maskawa (CKM) matrix parameters. This article presents first observation Cabibbo-suppressed }_{c}^{+}\to n{e}^{+}{\nu }_{e}$$ , utilizing 4.5 fb−1 electron-positron annihilation data collected with BESIII detector. A novel...
Hadronic transitions of ${\ensuremath{\chi}}_{cJ}\ensuremath{\rightarrow}{\ensuremath{\eta}}_{c}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ ($J=0$, 1, 2) are searched for using a sample $1.06\ifmmode\times\else\texttimes\fi{}{10}^{8}$ $\ensuremath{\psi}(3686)$ events collected with the BESIII detector at BEPCII storage ring. The ${\ensuremath{\eta}}_{c}$ is reconstructed ${K}_{S}^{0}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ensuremath{\mp}}$ and...
Using a sample of $1.06\ifmmode\times\else\texttimes\fi{}{10}^{8}$ ${\ensuremath{\psi}}^{\ensuremath{'}}$ decays collected by the BESIII detector, ${\ensuremath{\chi}}_{c0}$ and ${\ensuremath{\chi}}_{c2}$ into ${\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ $\ensuremath{\eta}\ensuremath{\eta}$ are studied. The branching fraction results...
With a sample of (225.2±2.8)×10(6) J/ψ events registered in the BESIII detector, J/ψ→γπ(+)π(-)η(') is studied using two η(') decay modes: η(')→π(+)π(-)η and η(')→γρ(0). The X(1835), which was previously observed by BESII, confirmed with statistical significance that larger than 20σ. In addition, π(+)π(-)η(') invariant-mass spectrum, X(2120) X(2370), are significances 7.2σ 6.4σ, respectively. For angular distribution radiative photon consistent expectations for pseudoscalar.
The decays $\chi_{cJ}\to\gamma V$ ($V=\phi, \rho^0, \omega$) are studied with a sample of radiative $\psip\to\gamma\chi_{cJ}$ events in $(1.06\pm0.04)\times 10^{8} \psip$ collected the BESIII detector. branching fractions determined to be: ${\cal B}(\chi_{c1}\to \gamma\phi)=(25.8\pm 5.2\pm 2.3)\times 10^{-6}$, \gamma\rho^0)=(228\pm 13\pm 22)\times and \gamma\omega)=(69.7\pm 7.2\pm 6.6)\times 10^{-6}$. decay $\chi_{c1}\to \gamma\phi$ is observed for first time. Upper limits at 90% confidence...
The cross section of the process $e^{+} e^{-} \rightarrow K^{+} K^{-}$ is measured at a number center-of-mass energies $\sqrt{s}$ from 2.00 to 3.08 GeV with BESIII detector Beijing Electron Positron Collider (BEPCII). results provide best precision achieved so far. A resonant structure around 2.2 observed in line shape. Breit-Wigner fit yields mass $M=2239.2 \pm 7.1 11.3$~and width $\Gamma=139.8\pm12.3\pm20.6$ MeV, where first uncertainties are statistical and second ones systematic. In...
Abstract Using inclusive decays of , a precise determination the number events collected with BESIII detector was performed. For two data sets taken in 2009 and 2012, numbers were recalculated to be respectively; these are good agreement previous measurements. sample 2017–2019, determined . The total where uncertainty is dominated by systematic effects, statistical negligible.
We study the process e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} at twelve center-of-mass energies from 4.6119 to 4.9509 GeV using data samples collected by BESIII detector BEPCII collider. The Born cross sections and effective form factors (|G_{eff}|) are determined with unprecedented precision after combining single double-tag methods based on decay Λ_{c}^{+}→pK^{-}π^{+}. Flat around 4.63 obtained no indication of resonant structure Y(4630), as reported Belle, is found. In addition, oscillatory...
Based on 4.4 fb−1 of e+e− annihilation data collected at the center-of-mass energies between 4.60 and 4.70 GeV with BESIII detector BEPCII collider, pure W-boson-exchange decay Λc+→Ξ0K+ is studied a full angular analysis. The corresponding asymmetry measured for first time to be αΞ0K+=0.01±0.16(stat)±0.03(syst). This result reflects noninterference effect S- P-wave amplitudes. phase shift amplitudes has two solutions, which are δp−δs=−1.55±0.25(stat)±0.05(syst) rad or...
The decays J/ψ → γ π+ π- π0 and are analyzed using a sample of 225×10(6) events collected with the BESIII detector. decay η(1405) f(0)(980)π0 large isospin violation is observed for first time. width f(0)(980) in dipion mass spectra anomalously narrower than world average. Decay rates three-pion η' also measured precisely.
We present measurements of the charmonium state h(c)(1P(1)) made with 106x10(6) psi' events collected by BESIII at BEPCII. Clear signals are observed for psi'-->pi0 h(c) and without subsequent radiative decay h(c)-->gamma eta(c). First absolute branching ratios B(psi'-->pi0 h(c)) = (8.4+/-1.3+/-1.0) x 10(-4) B(h(c)-->gamma eta(c)) (54.3+/-6.7+/-5.2)% presented. A statistics-limited determination previously unmeasured width leads to an upper limit Gamma(h(c))<1.44 MeV (90% confidence)....
This paper presents a summary of beam-induced backgrounds observed in the ATLAS detector and discusses methods to tag remove background contaminated events data. Trigger-rate based monitoring beam-related is presented. The correlations with machine conditions, such as residual pressure beam-pipe, are discussed. Results from dedicated beam-background simulations shown, their qualitative agreement data evaluated. Data taken during passage unpaired, i.e. non-colliding, proton bunches used...
The Technical Design for the COMET Phase-I experiment is presented in this paper. an at J-PARC, Japan, which will search neutrinoless conversion of muons into electrons field aluminium nucleus ($\mu-e$ conversion, $\mu^- N \to e^- N$); a lepton flavor violating process. experimental sensitivity goal process $3.1\times10^{-15}$, or 90 % upper limit branching ratio $7\times 10^{-15}$, factor 100 improvement over existing limit. expected number background events 0.032. To achieve target and...
A measurement of the number J/ψ events collected with BESIII detector in 2009 and 2012 is performed using inclusive decays J/ψ. The taken recalculated to be (223.7 ± 1.4) × 106, which good agreement previous measurement, but significantly improved precision due improvements software. determined (1086.9 6.0) 106. In total, measured (1310.6 7.0) where uncertainty dominated by systematic effects statistical negligible.
The cross sections of $e^+e^- \rightarrow K^+K^-J/\psi$ at center-of-mass energies from 4.127 to 4.600~GeV are measured based on 15.6 fb$^{-1}$ data collected with the BESIII detector operating BEPCII storage ring. Two resonant structures observed in line shape sections. mass and width first structure be ($4225.3\pm2.3\pm21.5$) MeV ($72.9\pm6.1\pm30.8$)~MeV, respectively. They consistent those established $Y(4230)$. second is for time a statistical significance greater than 8$\sigma$,...
The number of J/ψ events collected with the BESIII detector at BEPCII from June 12 to July 28, 2009 is determined be (225.3±2.8) × 106 using →inclusive events, where uncertainty systematic error and statistical one negligible.
The exclusive process $e^+e^-\rightarrow\Lambda\bar{\Lambda}$, with $\Lambda \to p\pi^-$ and $\bar{\Lambda} \bar{p}\pi^+$, has been studied at $\sqrt{s} =$ 2.396 GeV for measurement of the $\Lambda$ electric magnetic form factors, $G_E$ $G_M$. A data sample, corresponding to an integrated luminosity 66.9 pb$^{-1}$, was collected BESIII detector this purpose. multi-dimensional analysis a complete decomposition spin structure reaction enables determination modulus ratio $R=|G_E/G_M|$ and,...
By analyzing 2.93 fb$^{-1}$ of data collected at $\sqrt s=3.773$ GeV with the BESIII detector, we measure absolute branching fraction ${\mathcal B}(D^{+}\rightarrow\bar K^0μ^{+}ν_μ)=(8.72 \pm 0.07_{\rm stat.} 0.18_{\rm sys.})\%$, which is consistent previous measurements within uncertainties but significantly improved precision. Combining Particle Data Group values B}(D^0\to K^-μ^+ν_μ)$, K^0 e^{+}ν_{e})$, and lifetimes $D^0$ $D^+$ mesons value μ^{+}ν_μ)$ measured in this work, determine...
Using a total of 9.0 fb^{-1} e^{+}e^{-} collision data with center-of-mass energies between 4.15 and 4.30 GeV collected by the BESIII detector, we search for processes e^{+}e^{-}→γX(3872) X(3872)→π^{0}χ_{cJ} J=0, 1, 2. We report first observation X(3872)→π^{0}χ_{c1}, new decay mode X(3872), statistical significance more than 5σ all systematic fit variations. Normalizing to previously established process X(3872)→π^{+}π^{-}J/ψ, find...
During the 2016-17 and 2018-19 running periods, 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 samples are primarily used for study excited charmonium charmoniumlike states. By analyzing di-muon process $e^{+}e^{-} \to (\gamma_{\rm ISR/FSR}) \mu^{+}\mu^{-}$, we measure with a precision 0.6 MeV. Through run-by-run study, find that were stable throughout most data-taking period.