Time Dependent Dalitz Analysis of B0 -> D- K0 Pi+ Decays for the Measurement of 2beta+gamma with the BaBar Detector

Download or read book Time Dependent Dalitz Analysis of B0 -> D- K0 Pi+ Decays for the Measurement of 2beta+gamma with the BaBar Detector written by Francesco Polci and published by . This book was released on 2007 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: The CP violation is explained in the Standard Model with three quark generations with an irreducible phase in the Cabibbo-Kobayashi-Maskawa quark mixing matrix. The unitarity of this matrix can be represented in a complex plane as a triangle (called Unitarity Triangle). The measurement of the parameters of the triangle is a powerful test of the Standard Model description of the CP violation. This thesis tries to measure the weak phase 2beta+ gamma through the B0 -> D+ K0 Pi- decays. Respect to the two body decays B0 -> D(*)+ Pi- and B0 -> D+ Rho- presently used for the measurement of the same weak phase, the B0 -> D+ K0 Pi- decays should show up a larger CP asymmetry and does not rely on any theoretical assumption. After a review of all the methods for the measurement of 2beta+gamma, the thesis presents the results of a feasibility study of the measurement with the B0 -> D+ K0 Pi- decays . In a second part, the analysis performed on 316 fb-1 of data collected by the BaBar detector at the B-factory PEP2 is presented, from the selection of the events to the time-dependent Dalitz fit technique used in order to extract the weak phase 2beta+gamma as well as the amplitudes and phases of the intermediate resonances contributing to the decay. The result of the analysis gives the following estimation: 2beta+gamma = 89 +/- 53(stat) +23-14(syst) degrees with an irreducible ambiguity of 180 degrees.