Lifetime Measurement of fully hadronic reconstructed {\it B} collected by the dedicate I.P. based trigger

Thanks to its i.p. based trigger, CDF is able to collect large amount of {\it B} reconstructed in hadronic decays. One of most important features of hadronic decays is that can be fully reconstructed avoiding,in this way, the dependence from K factor that is a typical issue of semileptonic decays. More over CDF has the possibility to reconstruct also $B_{s}$ mesons, that can produced in high energy collision between $p$ and $\bar{p}$, but not in $B-factories$. Anyway the sample selection performed by trigger itself, sculpts the signal lifetime distribution that could no longer be described with a convolution between exponential and Gaussian. Understanding the trigger bias and perform a lifetime measurement in these sample is a challenging analysis. We present the results of the lifetime measurement performed on this sample and the fitting techniques used to understand the trigger bias