Measurement of the CP-even fraction of D0 → K +K-π+π-

作者：Ablikim, M.; Achasov, M. N.; Adlarson, P.; Albrecht, M.; Aliberti, R.; Amoroso, A.; An, M. R.; An, Q.; Bai, Y.; Bakina, O.; Ferroli, R. Baldini; Balossino, I.; Ban, Y.; Batozskaya, V.; Becker, D.; Begzsuren, K.; Berger, N.; Bertani, M.; Bettoni, D.; Bianchi, F.; Bianco, E.; Bloms, J.; Bortone, A.; Boyko, I; Briere, R. A.; Brueggemann, A.; Cai, H.; Cai, X.; Calcaterra, A.; Cao, G. F.; Cao, N.; Cetin, S. A.; Chang, J. F.; Chang, W. L.; Che, G. R.; Chelkov, G.; Chen, C.; Chen, Chao; Chen, G.

来源：Physical Review D, 2023, 107(3): 032009.

DOI：10.1103/PhysRevD.107.032009

A determination of the CP-even fraction F thorn in the decay D-0 -> K+K- pi(+) pi- is presented. Using 2.93 fb(-1) of e(+) e(-) -> psi(3770) -> D (D) over bar data collected by the BESIII detector, one charm meson is reconstructed in the signal mode and the other in a CP eigenstate or the decay D -> K-S,L(0) pi(+) pi(-). Analysis of the relative rates of these double-tagged events yields the result F+= 0.730 +/- 0.037 +/- 0.021, where the first uncertainty is statistical and the second is systematic. This is the first model-independent measurement of F thorn in D-0 -> K+ K-pi(+) pi(-) decays.