Measurements of lifetimes and a limit on the lifetime difference in the neutral D meson system

Journal Article · Mon Mar 01 04:00:00 EST 1999 · Phys.Rev.Lett.

DOI:https://doi.org/10.1103/PhysRevLett.83.32· OSTI ID:1893402

Aitala, E. M.

Using the large hadroproduced charm sample collected in experiment E791 at Fermilab, we report the first directly measured constraint on the decay-width difference Delta Gamma for the mass eigenstates of the D0-D0bar system. We obtain our result from lifetime measurements of the decays D0 --> K-pi+ and D0 --> K-K+, under the assumption of CP invariance, which implies that the CP eigenstates and the mass eigenstates are the same. The lifetime of D0 --> K-K+ (the CP-even final state is \tau_KK = 0.410 +/- 0.011 +/- 0.006 ps, and the lifetime of D0 --> K-pi+ (an equal mixture of CP-odd and CP-even final states is tau_Kpi = 0.413 +/- 0.003 +/- 0.004 ps. The decay-width difference is Delta Gamma = 2(Gamma_KK - Gamma_Kpi) = 0.04 +/- 0.14 +/- 0.05 ps^-1. We relate these measurements to measurements of mixing in the neutral D-meson system.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
• Contributing Organization: E791
• DOE Contract Number: AC02-07CH11359
• OSTI ID: 1893402
• Report Number(s): FERMILAB-PUB-99-036-E; arXiv:hep-ex/9903012; oai:inspirehep.net:496510
• Journal Information: Phys.Rev.Lett., Journal Name: Phys.Rev.Lett. Vol. 83
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS