Search for New Physics in the B⁰₂→J/ΨΦ and B⁰₂→ΦΦ Decays at CDF

Thesis/Dissertation · Sat Dec 01 00:00:00 EST 2012

DOI:https://doi.org/10.2172/1248356· OSTI ID:1248356

Dorigo, Mirco ^[1]

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1. Univ. of Trieste (Italy)

We present a search for physics beyond the standard model (SM) through a measurement of the violation of the charge-parity (CP) symmetry in two decays of the B⁰₂ meson using data collected by the Collider Detector at Fermilab (CDF) in proton-antiproton collisions at the center-of-mass energy of 1.96TeV. We exploit the decays B⁰₂→J/Ψ(→ μ⁺μ^-)(→ K⁺K^-) and B⁰₂→Φ (→ K⁺K^-)Φ(→ K⁺K^-), for which the SM accurately predicts very small or vanishing CP violation; both decay modes are very sensitive to new sources of CP violation expected in a broad class of SM extensions. We analyze the time-dependent CP asymmetry of the B⁰₂→J/ΨΦ decays collected in the full CDF Run II dataset for providing the final measurement of the B⁰₂ -¯B⁰₂ mixing phase, 2β_s, and we present the first measurement of CP violation in B⁰₂→ΦΦ decays, through the determination of two time-integrated CP asymmetries, A_v and A_u, using an original method developed in this work. We find: -0.06 < β_s < 0.30 at the 68% confidence level; A_v = (-12.0 ± 6.4(stat) ± 1.6(syst))%; and A_u = (-0.7 ± 6.4(stat) ± 1.8(syst))%. In addition, we provide measurements of the decay width difference between the light and heavy mass eigenstates of the B⁰₂ meson,ΔΓ_s 0.068 ± 0.026(stat) ± 0.009(syst) ps^-1; and of their mean lifetime, τ_s = 1.528 ± 0.019(stat) ± 0.009(syst) ps. All results are among the most precise determinations from a single experiment and exhibit an excellent agreement with the SM predictions.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP)
• DOE Contract Number: AC02-07CH11359
• OSTI ID: 1248356
• Report Number(s): FERMILAB-THESIS-2012-13; 1126071
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS