122 results match your criteria: "Justus-Liebig-Universitaet Giessen[Affiliation]"

Study of the Decay and Production Properties of D_{s1}(2536) and D_{s2}^{*}(2573).

Phys Rev Lett

October 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Article Synopsis
  • The study investigates the processes e^{+}e^{-}→D_{s}^{+}D_{s1}(2536)^{-} and e^{+}e^{-}→D_{s}^{+}D_{s2}^{*}(2573)^{-} using data from the BESIII detector, focusing on a range of center-of-mass energies.
  • For the first time, the absolute branching fractions of the decay processes for D_{s1}(2536)^{-} and D_{s2}^{*}(2573)^{-} are measured, revealing values of 35.9% and 37.4% respectively.
  • The research identifies a resonant structure around 4.6 Ge
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Search for Rare Decays of D_{s}^{+} to Final States π^{+}e^{+}e^{-}, ρ^{+}e^{+}e^{-}, π^{+}π^{0}e^{+}e^{-}, K^{+}π^{0}e^{+}e^{-}, and K_{S}^{0}π^{+}e^{+}e^{-}.

Phys Rev Lett

September 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Article Synopsis
  • Scientists used special data from a detector to look for rare particle decays of a type called the D_{s}^{+} decay, focusing on how it might change into other particles like kaons or pions.
  • They found strong evidence for the decay D_{s}^{+}→π^{+}ϕ and also discovered a new decay D_{s}^{+}→ρ^{+}ϕ, both involving particles that decay into pairs of electrons.
  • However, they didn't find strong signals for three other types of decays they were looking for, and set limits on how often those changes could happen.
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Strong and Weak CP Tests in Sequential Decays of Polarized Σ^{0} Hyperons.

Phys Rev Lett

September 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Article Synopsis
  • The study investigates the J/ψ and ψ(3686) decays into Σ^{0}Σ[over ¯]^{0} processes using data from the BESIII detector, which has extensive datasets.
  • It presents the first measurements of parity-violating decay parameters for Σ^{0} and Σ[over ¯]^{0}, suggesting implications for strong CP symmetry through their asymmetries.
  • The findings include the observation of opposite transverse polarizations of Σ^{0} hyperons in these decays and the ratio of S-wave to D-wave contributions, contributing valuable insights into charmonium state dynamics.
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Precise Measurement of Born Cross Sections for e^{+}e^{-}→DD[over ¯] at sqrt[s]=3.80-4.95  GeV.

Phys Rev Lett

August 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Article Synopsis
  • Data samples from the BESIII detector at the BEPCII collider were used to measure the Born cross sections for the e^{+}e^{-}→D^{0}D[over ¯]^{0} and D^{+}D^{-} processes with high precision.
  • Observations revealed clear peaks in the line shapes corresponding to various mass ranges, including G(3900), ψ(4040), ψ(4160), Y(4260), and ψ(4415).
  • These findings provide important experimental insights into the production of hadrons, particularly in the open-charm region.
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Measurements of Normalized Differential Cross Sections of Inclusive η Production in e^{+}e^{-} Annihilation at Energy from 2.0000 to 3.6710 GeV.

Phys Rev Lett

July 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Using data samples collected with the BESIII detector operating at the BEPCII storage ring, the cross section of the inclusive process e^{+}e^{-}→η+X, normalized by the total cross section of e^{+}e^{-}→hadrons, is measured at eight center-of-mass energy points from 2.0000 to 3.6710 GeV.

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First Study of Antihyperon-Nucleon Scattering Λ[over ¯]p→Λ[over ¯]p and Measurement of Λp→Λp Cross Section.

Phys Rev Lett

June 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Using (10.087±0.044)×10^{9} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the processes Λp→Λp and Λ[over ¯]p→Λ[over ¯]p are studied, where the Λ/Λ[over ¯] baryons are produced in the process J/ψ→ΛΛ[over ¯] and the protons are the hydrogen nuclei in the cooling oil of the beam pipe.

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First Observation of a Three-Resonance Structure in e^{+}e^{-}→Nonopen Charm Hadrons.

Phys Rev Lett

May 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

We report the measurement of the inclusive cross sections for e^{+}e^{-}→nOCH (where nOCH denotes non-open charm hadrons) with improved precision at center-of-mass (c.m.) energies from 3.

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Determination of Spin-Parity Quantum Numbers of X(2370) as 0^{-+} from J/ψ→γK_{S}^{0}K_{S}^{0}η^{'}.

Phys Rev Lett

May 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Based on (10087±44)×10^{6}  J/ψ events collected with the BESIII detector, a partial wave analysis of the decay J/ψ→γK_{S}^{0}K_{S}^{0}η^{'} is performed. The mass and width of the X(2370) are measured to be 2395±11(stat)_{-94}^{+26}(syst)  MeV/c^{2} and 188_{-17}^{+18}(stat)_{-33}^{+124}(syst)  MeV, respectively. The corresponding product branching fraction is B[J/ψ→γX(2370)]×B[X(2370)→f_{0}(980)η^{'}]×B[f_{0}(980)→K_{S}^{0}K_{S}^{0}]=(1.

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Observation of Structures in the Processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2}.

Phys Rev Lett

April 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

We present measurements of the Born cross sections for the processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2} at center-of-mass energies sqrt[s] from 4.308 to 4.951 GeV.

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Observation of the Anomalous Shape of X(1840) in J/ψ→γ3(π^{+}π^{-}) Indicating a Second Resonance Near pp[over ¯] Threshold.

Phys Rev Lett

April 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Using a sample of (10087±44)×10^{6}  J/ψ events, which is about 45 times larger than that was previously analyzed, a further investigation on the J/ψ→γ3(π^{+}π^{-}) decay is performed. A significant distortion at 1.84  GeV/c^{2} in the line shape of the 3(π^{+}π^{-}) invariant mass spectrum is observed for the first time, which could be resolved by two overlapping resonant structures, X(1840) and X(1880).

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Coupled-Channel Analysis of the χ_{c1}(3872) Line Shape with BESIII Data.

Phys Rev Lett

April 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

We perform a study of the χ_{c1}(3872) line shape using the data samples of e^{+}e^{-}→γχ_{c1}(3872), χ_{c1}(3872)→D^{0}D[over ¯]^{0}π^{0}, and π^{+}π^{-}J/ψ collected with the BESIII detector. The effects of the coupled channels and the off-shell D^{*0} are included in the parametrization of the line shape. The line shape mass parameter is obtained to be M_{X}=(3871.

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Study of the f_{0}(980) and f_{0}(500) Scalar Mesons through the Decay D_{s}^{+}→π^{+}π^{-}e^{+}ν_{e}.

Phys Rev Lett

April 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Using e^{+}e^{-} collision data corresponding to an integrated luminosity of 7.33  fb^{-1} recorded by the BESIII detector at center-of-mass energies between 4.128 and 4.

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Observation of D^{+}→K_{S}^{0}a_{0}(980)^{+} in the Amplitude Analysis of D^{+}→K_{S}^{0}π^{+}η.

Phys Rev Lett

March 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

We perform for the first time an amplitude analysis of the decay D^{+}→K_{S}^{0}π^{+}η and report the observation of the decay D^{+}→K_{S}^{0}a_{0}(980)^{+} 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.

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We present cross sections for the reaction e^{+}e^{-}→K_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.

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Investigation of the ΔI=1/2 Rule and Test of CP Symmetry through the Measurement of Decay Asymmetry Parameters in Ξ^{-} Decays.

Phys Rev Lett

March 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Using (10087±44)×10^{6}  J/ψ events collected with the BESIII detector, numerous Ξ^{-} and Λ decay asymmetry parameters are simultaneously determined from the process J/ψ→Ξ^{-}Ξ[over ¯]^{+}→Λ(pπ^{-})π^{-}Λ[over ¯](n[over ¯]π^{0})π^{+} and its charge-conjugate channel. The precisions of α_{Λ0} for Λ→nπ^{0} and α[over ¯]_{Λ0} for Λ[over ¯]→n[over ¯]π^{0} compared to world averages are improved by factors of 4 and 1.7, respectively.

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By analyzing 7.33  fb^{-1} of e^{+}e^{-} annihilation data collected at center-of-mass energies between 4.128 and 4.

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Determination of the Σ^{+} Timelike Electromagnetic Form Factors.

Phys Rev Lett

February 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Based on data samples collected with the BESIII detector at the BEPCII collider, the process e^{+}e^{-}→Σ^{+}Σ[over ¯]^{-} is studied at center-of-mass energies sqrt[s]=2.3960, 2.6454, and 2.

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First Measurement of the Decay Asymmetry in the Pure W-Boson-Exchange Decay Λ_{c}^{+}→Ξ^{0}K^{+}.

Phys Rev Lett

January 2024

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Based on 4.4  fb^{-1} of e^{+}e^{-} annihilation data collected at the center-of-mass energies between 4.60 and 4.

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Observation of a Vector Charmoniumlike State at 4.7  GeV/c^{2} and Search for Z_{cs} in e^{+}e^{-}→K^{+}K^{-}J/ψ.

Phys Rev Lett

November 2023

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Using data samples with an integrated luminosity of 5.85  fb^{-1} collected at center-of-mass energies from 4.61 to 4.

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Test of CP Symmetry in Hyperon to Neutron Decays.

Phys Rev Lett

November 2023

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

The quantum entangled J/ψ→Σ^{+}Σ[over ¯]^{-} pairs from (1.0087±0.0044)×10^{10}  J/ψ events taken by the BESIII detector are used to study the nonleptonic two-body weak decays Σ^{+}→nπ^{+} and Σ[over ¯]^{-}→n[over ¯]π^{-}.

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Measurement of Energy-Dependent Pair-Production Cross Section and Electromagnetic Form Factors of a Charmed Baryon.

Phys Rev Lett

November 2023

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

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 the BESIII detector at the BEPCII collider.

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Determination of Spin-Parity Quantum Numbers for the Narrow Structure near the pΛ[over ¯] Threshold in e^{+}e^{-}→pK^{-}Λ[over ¯]+c.c.

Phys Rev Lett

October 2023

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

A narrow structure in the pΛ[over ¯] system near the mass threshold, named as X(2085), is observed in the process e^{+}e^{-}→pK^{-}Λ[over ¯] with a statistical significance greater than 20σ. Its spin and parity are determined for the first time to be J^{P}=1^{+} in an amplitude analysis, with a statistical significance greater than 5σ over other quantum numbers (0^{-},1^{-} and 2^{+}). The pole positions of X(2085) are measured to be M_{pole}=(2084_{-2}^{+4}±9)  MeV and Γ_{pole}=(58_{-3}^{+4}±25)  MeV, where the first uncertainties are statistical and the second ones are systematic.

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Precise Measurement of the e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-} Cross Sections at Center-of-Mass Energies from Threshold to 4.95 GeV.

Phys Rev Lett

October 2023

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

The process e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-} is studied with a semi-inclusive method using data samples at center-of-mass energies from threshold to 4.95 GeV collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross sections of the process are measured for the first time with high precision in this energy region.

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First Experimental Study of the Purely Leptonic Decay D_{s}^{*+}→e^{+}ν_{e}.

Phys Rev Lett

October 2023

State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.

Using 7.33  fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at the BEPCII collider, we report the first experimental study of the purely leptonic decay D_{s}^{*+}→e^{+}ν_{e}. Our data contain a signal of this decay with a statistical significance of 2.

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We report on the first search for Λ[over ¯]-Λ oscillations in the decay J/ψ→pK^{-}Λ[over ¯]+c.c. by analyzing 1.

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