Study of the decays χ c J → Λ Λ ¯ ϕ

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doi:10.1103/PhysRevD.110.032016

Title: Study of the decays $χ_{c J} \to Λ \bar{Λ} ϕ$

Journal Article · 15 August 2024 · Physical Review. D.

DOI: https://doi.org/10.1103/PhysRevD.110.032016 · OSTI ID:2429625

Ablikim, M.; Achasov, M. N.; Adlarson, P.; Afedulidis, O.; Ai, X. C.; Aliberti, R.; Amoroso, A.; An, Q.; Bai, Y.; Bakina, O.; Balossino, I.; Ban, Y.; Bao, H. -R.; Batozskaya, V.; Begzsuren, K.; Berger, N.; Berlowski, M.; Bertani, M.; Bettoni, D.; Bianchi, F. more »

Based on $(2712.4 \pm 14.3) \times 10^{6}$ $e^{+} e^{-} \to ψ (3686)$ events collected with the BESIII detector operating at the BEPCII Collider, we report the first evidence of $χ_{c 0} \to Λ \bar{Λ} ϕ$ decays and the first observation of $χ_{c 1, 2} \to Λ \bar{Λ} ϕ$ decays, with significances of $4.1 σ$ , $11.3 σ$ and $13.0 σ$ , respectively. The decay branching fractions of $χ_{c 0, 1, 2} \to Λ \bar{Λ} ϕ$ are measured to be $(2.99 \pm 1.24 \pm 0.19) \times 10^{- 5}$ , $(6.01 \pm 0.90 \pm 0.40) \times 10^{- 5}$ , and $(7.13 \pm 0.81 \pm 0.36) \times 10^{- 5}$ , where the first uncertainties are statistical and the second systematic. No obvious enhancement near the $Λ \bar{Λ}$ production threshold or excited $Λ$ state is found in the $Λ ϕ$ (or $\bar{Λ} ϕ$ ) system. Published by the American Physical Society 2024

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Sponsoring Organization:: USDOE

Grant/Contract Number:: FG02-05ER41374

OSTI ID:: 2429625

Journal Information:: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 3 Vol. 110; ISSN PRVDAQ; ISSN 2470-0010

Publisher:: American Physical SocietyCopyright Statement

Country of Publication:: United States

Language:: English

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