Measurement of the Oscillation Frequency of B_s Mesons in the Hadronic Decay Mode B_s→ π D_s(Φ π)X with the D0 Detector at the Fermilab Tevatron Collider

Thesis/Dissertation · Sun Mar 01 00:00:00 EST 2009

DOI:https://doi.org/10.2172/960260· OSTI ID:960260

Weber, Gernot August ^[1]

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1. Univ. of Mainz (Germany). Inst. for Physics

The standard model (SM) of particle physics is a theory, describing three out of four fundamental forces. In this model the Cabibbo-Kobayashi-Maskawa (CKM) matrix describes the transformation between the mass and weak eigenstates of quarks. The matrix properties can be visualized as triangles in the complex plane. A precise measurement of all triangle parameters can be used to verify the validity of the SM. The least precisely measured parameter of the triangle is related to the CKM element |V_td|, accessible through the mixing frequency (oscillation) of neutral B mesons, where mixing is the transition of a neutral meson into its anti-particle and vice versa. It is possible to calculate the CKM element |V_td| and a related element |V_ts| by measuring the mass differences Δm_d(Δm_s) between neutral B_d and $$\bar{B}$$_d (B_s and $$\bar{B}$$_s) meson mass eigenstates. This measurement is accomplished by tagging the initial and final state of decaying B mesons and determining their lifetime. Currently the Fermilab Tevatron Collider (providing p$$\bar{p}$$ collisions at {radical}s = 1.96 TeV) is the only place, where B_s oscillations can be studied. The first selection of the 'golden', fully hadronic decay mode B_s → πD_s(Φπ)X at D0 is presented in this thesis. All data, taken between April 2002 and August 2007 with the D0 detector, corresponding to an integrated luminosity of integral Ldt = 2.8 fb^-1 is used. The oscillation frequency Δm_s and the ratio |V_td|/|V_ts| are determined as Δm_s = (16.6_-0.4^+0.5(stat)_-0.3^+0.4(sys)) ps^-1, |V_td|/|V_ts| = 0.213_-0.003^+0.004(exp) ± 0.008(theor). These results are consistent with the standard model expectations and no evidence for new physics is observable.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-07CH11359
• OSTI ID: 960260
• Report Number(s): FERMILAB-THESIS-2009-23; TRN: US0904595
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
DECAY
EIGENSTATES
FERMILAB TEVATRON
LIFETIME
LUMINOSITY
MASS DIFFERENCE
MESONS
OSCILLATIONS
PHYSICS
QUARKS
STANDARD MODEL
TRANSFORMATIONS
Experiment-HEP