Электронный каталог

Статья

Ablikim, M.
Investigation of the *DI=1/2 Rule and Test of CP Symmetry Through the Measurement of Decay Asymmetry Parameters in *X*- Decays / M.Ablikim, O.Bakina, I.Boyko, G.Chelkov, D.Dedovich, I.Denysenko, P.Egorov, A.Guskov, Y.Nefedov, A.Sarantsev, A.Zhemchugov, [a.o.] // Physical Review Letters [Electronic resource]. – 2024. – Vol. 132, No. 10. – P. 101801. – URL: https://doi.org/10.1103/PhysRevLett.132.101801. – Bibliogr.: 41.

Using ð10087 *( 44Þ × 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− ¯Ξþ → Λðpπ−Þπ− ¯Λð ¯nπ0Þπþ and its charge-conjugate channel. The precisions of αΛ0 for Λ → nπ0 and ¯αΛ0 for ¯Λ → ¯nπ0 compared to world averages are improved by factors of 4 and 1.7, respectively. The ratio of decay asymmetry parameters of Λ → nπ0 to that of Λ → pπ−, hαΛ0i=hαΛ−i, is determined to be 0.873 *( 0.012þ0.011 −0.010 , where the first and the second uncertainties are statistical and systematic, respectively. The ratio is smaller than unity more than 5σ, which signifies the existence of the ΔI ¼ 3=2 transition in Λ for the first time. Besides, we test for CP symmetry in Ξ− → Λπ− and in Λ → nπ0 with the best precision to date.



ОИЯИ = ОИЯИ (JINR)2024
Спец.(статьи,препринты) = С 346.6г - Гиперонные резонансы