News&Events

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  Observation of D⁺→ K_S⁰π⁰μ⁺ν_μ, Test of Lepton Flavor Universality and First Angular Analysis of D⁺→K^*(892^)0barl⁺ν_l The BESIII collaboration has reported “Observation of D+→ KS0π0μ+νμ,, Test of Lepton Flavor Universality and First Angular Analysis of D+→K*(892)0barl+νl”. These results have been published in Physical Review Letters on October 21, 2025. [Phys. Rev. Lett. 135, 171801 (2025)].
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  Single Inclusive 𝜋^± and 𝐾^± Production in 𝑒⁺⁢𝑒⁻ Annihilation
  The BESIII collaboration has founded the validity of isospin symmetry in parton fragmentation processes through measurements of single inclusive π± and K± production. The results were published in Physical Review Letters on Oct. 8, 2025 [Phys. Rev. 135, 151901 (2025)].
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  First measurement of ratio for ϕ meson decays into K_S⁰ K_L⁰ and K⁺ K^- through amplitude analysis of D_S⁺→K_S⁰ K_L⁰ π⁺ The BESIII collaboration has reported the ratio of ϕ meson decays into KS0 KL0 and K+ K- in charm meson decays for the first time. The results have been published in Physics Review Letters on 15 October 2025 [Phys. Rev. Lett. 135, 161902 (2025)].
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  BESIII Physics and Software Workshop in Autumn 2025, Sep. 26-29, USC The BESIII Physics & Software workshop in Autumn 2025 was held during September 26-29th,2025 at University of South China (Hengyang, Hunan province).
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  Precision CP symmetry test and Polarization analysis in Σ⁺ decays The BESIII Collaboration has achieved a milestone in hyperon physics by performing the most precise test of CP symmetry and polarization analysis in Σ+ decays to date. The results have been published in Physical Review Letters on Oct. 1, 2025 [Phys. Rev. Lett. 135, 141804 (2025)].
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  Precise Measurement of the Form Factors in D⁰→K^*(892)^-μ⁺ν_μ  and Test of Lepton Universality with D⁰→K^*(892) Transition The BESIII collaboration has reported “Precise Measurement of the Form Factors in D0→K*(892)-μ+νμ and Test of Lepton Universality with D0→K*(892)-l+νl Decays”. These results have been published in Physical Review Letters on 10 September 2025. [Phys. Rev. Lett. 135, 111803 (2025)].
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  First Measurement of the Decay Dynamics in the Semileptonic Transition of the D⁺(0) into the Axial-vector Meson K₁(1270) The BESIII collaboration has reported “First Measurement of the Decay Dynamics in the Semileptonic Transition of the D+(0) into the Axial-vector Meson K1(1270)”. These results have been published in Physical Review Letters on 25 August 2025. [Phys. Rev. Lett. 135, 091801 (2025)].
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  Three Resonances in the Cross Section of e⁺ e^-→π⁺ π^- h_c The BESIII collaboration has reported the observation of three resonant structures in the cross section of e+ e-→π+ π- hc based on precise measurements at center-of-mass energies between 4.01 and 4.95 GeV. The cross section exhibits a plateau-like behavior between 4.3 and 4.5 GeV, followed by a sharp drop, revealing for the first time three distinct resonances. These resonances appear at masses of approximately 4.22, 4.33, and 4.47 GeV. The third structure was detected for the first time with a statistical significance exceeding 5σ. The results provide crucial insights into the nature of exotic particles, and have been published in Physical Review Letters on 11 August 2025 [Phys. Rev. Lett. 135, 071901].
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  Precision Measurement of the Branching Fraction of D⁺→μ⁺ν_μ The BESIII collaboration has reported the precision measurement of the branching fraction of the leptonic decay D+→μ+νμ​. This result has been published in Physical Review Letters on 04 August 2025. [Phys. Rev. Lett. 135, 061801 (2025)].
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  Collaboration Meeting in Summer 2025, Jul. 7 - 11, 2025, North China Electric Power University (Beijing, China) The BESIII Collaboration Meeting in Summer of 2025 was held at North China Electric Power University (Beijing Campus) from July 7th to July 11th, 2025.