Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
First Measurement of the Absolute Branching Fraction of 𝜂𝑐→𝛾𝛾 / The BESIII Collaboration ; Ачасов, Михаил Николаевич; Мучной, Николай Юрьевич и др.
в: Physical Review Letters, Том 137, № 7, 071802, 12.08.2026.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - First Measurement of the Absolute Branching Fraction of 휂푐→훾훾
AU - BESIII Collaboration
AU - Ачасов, Михаил Николаевич
AU - Мучной, Николай Юрьевич
AU - Николаев, Иван Борисович
N1 - The BESIII Collaboration thanks the staff of BEPCII [57] and the IHEP computing center for their strong support. This work is supported in part by National Key R&D Program of China under Contracts No. 2025YFA1613900, No. 2023YFA1606000, and No. 2023YFA1606704; National Natural Science Foundation of China under Contracts No. 11635010, No. 11935015, No. 11935016, No. 11935018, No. 12025502, No. 12035009, No. 12035013, No. 12061131003, 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; CAS Project for Young Scientists in Basic Research No. YSBR-117; the Strategic Priority Research Program of Chinese Academy of Sciences under Contract No. XDA0480600; CAS under Contract No. YSBR-101; 100 Talents Program of CAS; The Institute of Nuclear and Particle Physics 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, No. 2021.0299, and No. 2023.0315; 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.
PY - 2026/8/12
Y1 - 2026/8/12
N2 - We apply a tag-and-probe method to precisely measure the absolute branching fraction of the decay 휂푐 →훾훾 with the BESIII experiment at BEPCII. Starting with a large initial sample of (2712.4±14.3)×106 휓(3686) events, a sample of 0.16×106 휂푐 events is tagged via the golden channel 휓(3686)→휋0ℎ푐, ℎ푐 →훾휂푐, effectively avoiding interference effects. The absolute branching fraction of 휂푐 →훾훾 is measured for the first time to be ℬ(휂푐→훾훾)=(2.45±0.48stat±0.09syst)×10−4. Using the world average value of the total width of the 휂푐, the partial decay width of 휂푐 →훾훾 is calculated to be Γ(휂푐→훾훾)=(7.48±1.48stat±0.30syst) keV.
AB - We apply a tag-and-probe method to precisely measure the absolute branching fraction of the decay 휂푐 →훾훾 with the BESIII experiment at BEPCII. Starting with a large initial sample of (2712.4±14.3)×106 휓(3686) events, a sample of 0.16×106 휂푐 events is tagged via the golden channel 휓(3686)→휋0ℎ푐, ℎ푐 →훾휂푐, effectively avoiding interference effects. The absolute branching fraction of 휂푐 →훾훾 is measured for the first time to be ℬ(휂푐→훾훾)=(2.45±0.48stat±0.09syst)×10−4. Using the world average value of the total width of the 휂푐, the partial decay width of 휂푐 →훾훾 is calculated to be Γ(휂푐→훾훾)=(7.48±1.48stat±0.30syst) keV.
KW - Leptonic, semileptonic & radiative decays
KW - Quarkonia
KW - Lepton colliders
UR - https://www.scopus.com/pages/publications/105048163692
U2 - 10.1103/whyk-ykjw
DO - 10.1103/whyk-ykjw
M3 - Article
VL - 137
JO - Physical Review Letters
JF - Physical Review Letters
SN - 0031-9007
IS - 7
M1 - 071802
ER -
ID: 83242650