A B 0 s meson is a bound state of (bs) quarks. An anti-B 0 s meson is a (bs) bound state.

1. Purdue Analysis Purdue Analysis Spectator model: light quarks do not participate in the decay of a bottom hadrons Lifetimes of B0, B+, B0s and b should be approximately equal... b b q c c q q q q q Theory - including spectator effects to order 1/mb4 yields the predictions: Experiment – Reconstruct B+, B0, B0s and b decays, measure momentum and decay length Results from CDF – Larger than expected? Dominated by semi-leptonic b decays which require a model for the b form factor. Fully reconstructed decay: independent of form factor. Heavy Flavor Physics with the CDF II Detector Matthew Jones A few examples of B0s Oscillations and Lifetime Difference Precision Mass and Lifetime Measurements • Level 1 trigger: two oppositely charged muons, pT > 1.5 GeV • Level 2 trigger: no additional requirements • Level 3 trigger: full event reconstruction, 2.7 < m(+-) < 4.0 GeV/c2 • Offline analysis: reconstruct , combine with or • A B0s meson is a bound state of (bs) quarks. • An anti-B0s meson is a (bs) bound state. • Elementary Quantum Mechanics says that their time evolution is described by Schrodenger’s equation: • If the off-diagonal terms in the Hamiltonian are non-zero then • B0s and anti-B0s mesons are not the free-particle eigenstates • The free-particle eigenstates that diagonalize the Hamiltonian are: • BH and BL have different masses: • Mass difference is • When strong interactions produce a B0s state, the BH and BL components interfere with each other and oscillate with a frequency of ms. • The frequency depends on elements of the CKM matrix: Early results – now we have 10 times more data! World’s largest samples of fully reconstructed B0s and b decays CP odd CP even this one is Heavy this one is Light Precise constraint on this side of the Unitary Triangle Unambiguous signature of oscillations observed September 25, 2006... A major goal of the CDF II physics program! (Oscillation frequency of 2,828 GHz) The CP-even and CP-odd B0s states should have different lifetimes: Prediction: ( s = 1/(B0s) ) CDF analyses decays which are a mixture of CP-even and CP-odd final states. CP-even and CP-odd components separated by analyzing the angular distributions of the decay products: New CDF Discoveries: The -b=(ddb), +b=(uub) and b=(dsb)! Recent CDF result: We still need more precision... Measure B0s lifetime using : Pure CP-odd! Lifetime measurements will help to understand (b)/(B0d). • Need 1 or 2 new students to carry out these analyses. • Data has already been recorded – work can start NOW! • Lots of experience from previous analyses at CDF. • Fast thesis topics... November 13, 2007