New Measurements from Fully Reconstructed Hadronic Final States of the $B^0_2$ Meson at CDF II Experiment
Author | : |
Publisher | : |
Total Pages | : 164 |
Release | : 2006 |
ISBN-10 | : OCLC:982482033 |
ISBN-13 | : |
Rating | : 4/5 ( Downloads) |
Download or read book New Measurements from Fully Reconstructed Hadronic Final States of the $B^0_2$ Meson at CDF II Experiment written by and published by . This book was released on 2006 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis reports the reconstruction and lifetime measurement of B+, B$0/atop{d}$ and B$0/atop{s}$ mesons, performed using fully reconstructed hadronic decays collected by a dedicated trigger at CDF II experiment. This dedicated trigger selects significantly displaced tracks from primary vertex of p$\bar{p}$ collisions generated at Tevatron collider, obtaining, in this way, huge data samples enriched of long-lived particles, and is therefore suitable for reconstruction of B meson in hadronic decay modes. Due to the trigger track impact parameter selections, the proper decay time distributions of the B mesons no longer follow a simply exponential decay law. This complicates the lifetime measurement and requires a correct understanding and treatment of all the involved effects to keep systematic uncertainties under control. This thesis presents a method to extract the lifetime of B mesons in "ct- biased" samples, based on a Monte Carlo approach, to correct for the effects of the trigger and analysis selections. We present the results of this method when applied on fully re- constructed decays of B collected by CDF II in the data taking runs up to August 2004, corresponding to an integrated luminosity of about 360 pb-1. The lifetimes are extracted using the decay modes B+ 2!$\bar{D}$0[pi]+, B$0\atop{d}$ 2!D-[pi]+, B$0\atop{d}$ 2!D-[pi]+[pi]-[pi]+, B$0\atop{s}$ 2!D$-\atop{s}$[pi]+ and B$0\atop{s}$ 2!D$-\atop{s}$ [pi]+[pi]-[pi]+(and c.c.) and performing combined mass-lifetime unbinned maximum likelihood fits.