Ph.D. Thesis by Owen R. Long

Advisor: Prof. Nigel Lockyer

University of Pennsylvania, Philadelphia, PA, 1997

Title
-----
A Proper Time Dependent Measurement of Delta m_d Using Jet
  Charge and Soft Lepton Flavor Tagging

Abstract
--------
  This thesis presents a proper time dependent measurement
of the B_d^0 mixing frequency Delta m_d using jet charge and 
soft lepton flavor tagging in p-bar p collisions at 
sqrt s  = 1.8 TeV.  The measurement uses the inclusive e 
and mu trigger data of the CDF detector from an integrated 
luminosity of 91 1/pb.  The proper time at decay is measured 
from a partial reconstruction of the B associated with the 
trigger lepton.  The measurement of $\Delta m_d$ yields
 
 Delta m_d = 0.50 +/- 0.05 +/- 0.05  hbar 1/ps
 
where the first error is statistical and the second
systematic.  The flavor tagging methods used give
a measured effective efficiency epsilon D^2 of 

 Jet Charge:  epsilon D^2 = (0.78 +/- 0.12 +/- 0.09) %
 Soft Lepton: epsilon D^2 = (1.07 +/- 0.09 +/- 0.10) %

where the first error is statistical and the second
systematic.







Posted to /cdf/pub/thesis/cdf4680_ORL-Thesis.ps
    http://www-cdf.fnal.gov/thesis/cdf4680_ORL-Thesis.ps

Posted by owen@cdfsga.fnal.gov