This web page summarizes the results for the measurement of the /\_b Lifetime in /\_b → /\_c π, based on a 1070 ± 60 pb^-1 sample of data, collected using the CDF two displaced track trigger. It was approved by the CDF B group on 06/18/2008.

The analysis employs a 2-step fit, first a binned fit of the /\_b mass and second an unbinned maximum likelihood 2D fit of the decay length and its error distributions to extract the /\_b lifetime. We measure

cτ(/\b) = 422.8 ± 13.8(stat.) ± 8.8 (syst.) μm

Using our measurement of the /\_b lifetime and the PDG 2007 world average B⁰ lifetime, we obtain

&tau(/\b)/&tau(B0) = 0.922 ± 0.039

A more detailed summary of the results can be found here: PDF.

[/\b Decay Length Projection]

[Comparison with Other Experiments]

EPS and GIF Figures for Download:

• Figure 1: /\_b selection cuts (.eps)(.gif)
• Figure 2: /\_b mass (.eps)(.gif)
• Figure 3: /\_b signal and background yields table (.eps)(.gif)
• Figure 4: SVT efficiency distribution (.eps)(.gif)
• Figure 5: /\_b lifetime fit: Decay length (ct) projection (.eps)(.gif)
• Figure 6: Systematics table (.eps)(.gif)
• Figure 7: /\_b lifetime comparison with other experiments (.eps)(.gif)
• Figure 8: /\_b lifetime comparison: The 2006 status (.eps)(.gif)
• Figure 9: ct error distributions in data(.eps)(.gif)
• Figure 10: Lifetime fit stability in Monte Carlo over possible /\_b lifetime values(.eps)(.gif)
• Figure 11: Systematic Error: SVT correction as a function of L_xy(.eps)(.gif)
• Figure 12: Data vs. Monte Carlo comparison: track pairs satisfying the Two Track Trigger(.eps)(.gif)
• Figure 13: Data vs. Monte Carlo comparison: /\_c decay length distribution(.eps)(.gif)