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Title: Measurement of CP violation in $$B_s^0\to J/\psi \phi$$ decays using the full CDF data set

We report on the final measurement of the CP-violating $$B_s^0$$ mixing phase $$\beta_s^{J/ψφ}$$ in √s = 1.96 TeV proton-antiproton collisions collected with the Collider Detector at the Fermilab Tevatron collider. Using a sample corresponding to 9.6 fb-1 of integrated luminosity, we fit the decay-time evolution of $$B_s^0$$ → J/ψ (→ μ+ μ-) φ (→ K+ K) decays in which the b-quark content at production and the CP parity of the final state are identified. The interference of decays with and without mixing renders the $$B_s^0$$ mixing phase observable. The phase is determined to be -0.06 < $$\beta_s^{J/ψφ}$$ < 0.30 at 68% confidence level. The decay-width difference between heavy and light $$B_s^0$$ eigenstates, and the average $$B_s^0$$ lifetime are also determined to be ΔΓs = 0.068 ± 0.027 ps-1 and $$\tau_s$$ = 1.528 ± 0.021 ps, respectively. These results are among the world’s most precise from a single experiment, and compatible with standard model predictions.
Authors:
 [1]
  1. Univ. of Pisa (Italy)
Publication Date:
OSTI Identifier:
1247708
Report Number(s):
FERMILAB-THESIS--2012-14
1126172
DOE Contract Number:
AC02-07CH11359
Resource Type:
Thesis/Dissertation
Research Org:
Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS