Measurement of the $\Lambda_b^{0}$ lifetime using the fully reconstructed 
final state $J/\psi \Lambda^{0}$ at CDF

Measurements of b-flavored hadron lifetimes provide an important
test of the Heavy Quark Expansion (HQE) used in the interpretation of weak decay data.
In this context, the lifetime of the $\Lambda_b^{0}$ baryon has been of particular 
interest since experiment and HQE theory have seemingly been at odds for more than a decade.
We present a precision measurement of the $\Lambda_b^{0}$ lifetime in the
fully reconstructed decay mode $\Lambda_b^{0} \rightarrow J/\psi \Lambda^{0}$
using $800$ pb$^{-1}$ of $p\bar{p}$ at $\sqrt{s}$ = 1.96 TeV collisons
collected by the Collider Detector at Fermilab (CDF) during Run II at the
Fermilab Tevatron.