Measurements of the Absolute Branching Fraction of the Semileptonic Decay Ξ−→Λ⁢𝑒−⁢¯𝜈𝑒 and the Axial Charge of Ξ−

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Measurements of the Absolute Branching Fraction of the Semileptonic Decay Ξ−→Λ⁢𝑒−⁢¯𝜈𝑒 and the Axial Charge of Ξ−. / BESIII Collaboration ; Ачасов, Михаил Николаевич ; Мучной, Николай Юрьевич et al.

In: Physical Review Letters, Vol. 137, No. 9, 091801, 24.08.2026.

Research output: Contribution to journal › Article › peer-review

BibTeX

@article{cf240d44d35c4f4086be0a144cb63e2d,

title = "Measurements of the Absolute Branching Fraction of the Semileptonic Decay Ξ−→Λ⁢푒−⁢¯휈푒 and the Axial Charge of Ξ−",

abstract = "Using (10 087±44)×106 퐽/휓 events collected with the BESIII detector, we study the semileptonic decay Ξ− →Λ⁢푒−⁢¯휈푒 for the first time at an electron-positron collider. The absolute branching fraction is determined for the first time to be (3.60±0.4⁢0stat±0.1⁢0syst)×10−4, which is 3.9 standard deviations below the world average. In addition, using an 11-dimensional angular analysis, the axial-vector to vector coupling 푔av is determined to be 0.18 ±0.0⁢7stat ±0.0⁢1syst. These results are used to test various SU(3)-flavor effective models. Under the SU(3)-flavor symmetry limit, the axial charge is found to be 푔퐻퐴 =0.22 ±0.0⁢8stat ±0.0⁢2syst. Despite using only 5% of the statistics of previous experiments, this analysis achieves a comparable precision for the axial charge.",

keywords = "Cabibbo–Kobayashi–Maskawa matrix, Electroweak interaction, Quark model, Baryons, W & Z bosons, Form factors, Symmetries",

author = "{BESIII Collaboration} and Ачасов, {Михаил Николаевич} and Мучной, {Николай Юрьевич} and Николаев, {Иван Борисович}",

note = "The BESIII Collaboration thanks the staff of BEPCII [34] and the IHEP computing center and the supercomputing center of the University of Science and Technology of China (USTC) for their strong support. We thank Ruixiang Shi for his insightful theoretical discussions. This work is supported in part by National Key R&D Program of China under Contracts No. 2023YFA1609400, No. 2023YFA1606000, No. 2023YFA1606704; National Natural Science Foundation of China (NSFC) under Contracts No. 11635010, No. 11935015, No. 11935016, No. 11935018, No. 12025502, No. 12035009, No. 12035013, No. 12061131003, No. 12105276, No. 12122509, No. 12192260, No. 12192261, No. 12192262, No. 12192263, No. 12192264, No. 12192265, No. 12221005, No. 12225509, No. 12235017, and No. 12361141819; the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; the Strategic Priority Research Program of Chinese Academy of Sciences under Contract No. XDA0480600; CAS under Contract No. YSBR-101; Joint Large-Scale Scientific Facility Funds of the NSFC and CAS under Contract No. U2032111; 100 Talents Program of CAS; CAS Youth Team Program under Contract No. YSBR-101; The Institute of Nuclear and Particle Physics (INPAC) and Shanghai Key Laboratory for Particle Physics and Cosmology; ERC under Contract No. 758462; German Research Foundation DFG under Contract No. FOR5327; Istituto Nazionale di Fisica Nucleare, Italy; Knut and Alice Wallenberg Foundation under Contracts No. 2021.0174 and No. 2021.0299; Ministry of Development of Turkey under Contract No. DPT2006K-120470; National Research Foundation of Korea under Contract No. NRF-2022R1A2C1092335; National Science and Technology fund of Mongolia; Polish National Science Centre under Contract No. 2024/53/B/ST2/00975; STFC (United Kingdom); Swedish Research Council under Contract No. 2019.04595; U.S. Department of Energy under Contract No. DE-FG02-05ER41374; Beijing Natural Science Foundation of China (BNSF) under Contract No. IS23014.",

year = "2026",

month = aug,

day = "24",

doi = "10.1103/zdc7-fcyf",

language = "English",

volume = "137",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society",

number = "9",

}

RIS

TY - JOUR

T1 - Measurements of the Absolute Branching Fraction of the Semileptonic Decay Ξ−→Λ⁢푒−⁢¯휈푒 and the Axial Charge of Ξ−

AU - BESIII Collaboration

AU - Ачасов, Михаил Николаевич

AU - Мучной, Николай Юрьевич

AU - Николаев, Иван Борисович

N1 - The BESIII Collaboration thanks the staff of BEPCII [34] and the IHEP computing center and the supercomputing center of the University of Science and Technology of China (USTC) for their strong support. We thank Ruixiang Shi for his insightful theoretical discussions. This work is supported in part by National Key R&D Program of China under Contracts No. 2023YFA1609400, No. 2023YFA1606000, No. 2023YFA1606704; National Natural Science Foundation of China (NSFC) under Contracts No. 11635010, No. 11935015, No. 11935016, No. 11935018, No. 12025502, No. 12035009, No. 12035013, No. 12061131003, No. 12105276, No. 12122509, No. 12192260, No. 12192261, No. 12192262, No. 12192263, No. 12192264, No. 12192265, No. 12221005, No. 12225509, No. 12235017, and No. 12361141819; the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; the Strategic Priority Research Program of Chinese Academy of Sciences under Contract No. XDA0480600; CAS under Contract No. YSBR-101; Joint Large-Scale Scientific Facility Funds of the NSFC and CAS under Contract No. U2032111; 100 Talents Program of CAS; CAS Youth Team Program under Contract No. YSBR-101; The Institute of Nuclear and Particle Physics (INPAC) and Shanghai Key Laboratory for Particle Physics and Cosmology; ERC under Contract No. 758462; German Research Foundation DFG under Contract No. FOR5327; Istituto Nazionale di Fisica Nucleare, Italy; Knut and Alice Wallenberg Foundation under Contracts No. 2021.0174 and No. 2021.0299; Ministry of Development of Turkey under Contract No. DPT2006K-120470; National Research Foundation of Korea under Contract No. NRF-2022R1A2C1092335; National Science and Technology fund of Mongolia; Polish National Science Centre under Contract No. 2024/53/B/ST2/00975; STFC (United Kingdom); Swedish Research Council under Contract No. 2019.04595; U.S. Department of Energy under Contract No. DE-FG02-05ER41374; Beijing Natural Science Foundation of China (BNSF) under Contract No. IS23014.

PY - 2026/8/24

Y1 - 2026/8/24

N2 - Using (10 087±44)×106 퐽/휓 events collected with the BESIII detector, we study the semileptonic decay Ξ− →Λ⁢푒−⁢¯휈푒 for the first time at an electron-positron collider. The absolute branching fraction is determined for the first time to be (3.60±0.4⁢0stat±0.1⁢0syst)×10−4, which is 3.9 standard deviations below the world average. In addition, using an 11-dimensional angular analysis, the axial-vector to vector coupling 푔av is determined to be 0.18 ±0.0⁢7stat ±0.0⁢1syst. These results are used to test various SU(3)-flavor effective models. Under the SU(3)-flavor symmetry limit, the axial charge is found to be 푔퐻퐴 =0.22 ±0.0⁢8stat ±0.0⁢2syst. Despite using only 5% of the statistics of previous experiments, this analysis achieves a comparable precision for the axial charge.

AB - Using (10 087±44)×106 퐽/휓 events collected with the BESIII detector, we study the semileptonic decay Ξ− →Λ⁢푒−⁢¯휈푒 for the first time at an electron-positron collider. The absolute branching fraction is determined for the first time to be (3.60±0.4⁢0stat±0.1⁢0syst)×10−4, which is 3.9 standard deviations below the world average. In addition, using an 11-dimensional angular analysis, the axial-vector to vector coupling 푔av is determined to be 0.18 ±0.0⁢7stat ±0.0⁢1syst. These results are used to test various SU(3)-flavor effective models. Under the SU(3)-flavor symmetry limit, the axial charge is found to be 푔퐻퐴 =0.22 ±0.0⁢8stat ±0.0⁢2syst. Despite using only 5% of the statistics of previous experiments, this analysis achieves a comparable precision for the axial charge.

KW - Cabibbo–Kobayashi–Maskawa matrix

KW - Electroweak interaction

KW - Quark model

KW - Baryons

KW - W & Z bosons

KW - Form factors

KW - Symmetries

UR - https://www.scopus.com/pages/publications/105049657210

U2 - 10.1103/zdc7-fcyf

DO - 10.1103/zdc7-fcyf

M3 - Article

VL - 137

JO - Physical Review Letters

JF - Physical Review Letters

SN - 0031-9007

IS - 9

M1 - 091801

ER -

ID: 83242408