Amplitude analyses of D-0 -%26gt; pi(+)pi(-)pi(+)pi(-)and D-0 -%26gt; K+K-pi(+)pi(-)decays

作者：d' Argent P; Skidmore N; Benton J; Dalseno J; Gersabeck E; Harnew S T; Naik P; Prouve C; Rademacker J

来源：The Journal of High Energy Physics, 2017, 2017(5): 143.

DOI：10.1007/JHEP05(2017)143

• Charm physics
• CP violation
• e plus -e- Experiments
• Flavor physics
• Spectroscopy

The resonant substructure of D-0 -> pi(+)pi pi(+)pi(-) decays is studied using data collected by the CLEO-c detector. An amplitude analysis is performed in order to disentangle the various intermediate state contributions. To limit the model complexity a data driven regularization procedure is applied. The prominent contributions are the decay modes D-0 -> a(1)(1260)(+) pi(-), D-0 -> sigma f(0) (1370) and D-0 -> rho(770)(0) rho(770)(0). The broad resonances a(1) (1260)(+), pi (1300)(+) and a(1) (1640)(+) are studied in detail, including quasi-model-independent parametrizations of their lineshapes. The mass and width of the a(1) (1260)(+) meson are determined to be m(a1) ((1260)+) = [1225 +/- 9 (stat) +/- 17 (syst) +/- 10 (model)] MeV/c(2) and Gamma(a1) ((1260)+) = [430 +/- 24 (stat) +/- 25 (syst) +/- 18 (model)] MeV. The amplitude model of D-0 -> K+ K-pi(+)pi(-) decays obtained from CLEO II.V, CLEO III, and CLEO-c data is revisited with improved lineshape parametrizations. The largest components are the decay modes D-0 -> phi(1020)rho(770)(0), D-0 -> K-1 (1270)(+) K- and D-0 -> K(1400)(+) K-.
The fractional CP-even content of the decay D-0 -> pi(+)pi(-)pi(+)pi(-) is calculated from the amplitude model to be F-+(4 pi) = [72:9 +/- 0:9 (stat)+/- 1:5 (syst)+/- 1:0 (model)] %, consistent with that obtained from a previous model-independent measurement. For D-0 -> K+ K- pi(+)pi(-) decays, the CP-even fraction is measured for the first time and found to be F-+(K K pi pi) = [75.3 +/- 1.8 (stat) +/- 3.3 (syst) +/- 3.5 (model)] %.
The global decay rate asymmetries between D-0 and (D) over bar (0) decays are measured to be A(CP)(4 pi) - [+0.54 +/- 1.04 (stat)+/- 0.51 (syst)]% and A(CP)(KK pi pi) - [+1.84 +/- 1.74 (stat)+/- 0.30 (syst)]%. A search for CP asymmetries in the amplitude components yields no evidence for CP violation in either decay mode.

• 出版日期2017-5-29