TY - THES AB - In decay processes of B mesons the so-called "heavy light currents" play an important role, for example in the determination of matrix elements of the CKM mixing matrix. The present thesis investigates various aspects of the strong interaction of the quarks participating in the heavy light current. The theory of strong interaction is Quantum Chromodynamics, which is treated in perturbation theory. After a short introduction to the relevant effective field theories, which are derived from QCD, some new results are presented. First the asymptotic behaviour of the perturbative series is investigated, and the second result are proofs of factorization theorems which are used to separate the perturbative from the nonperturbative contributions. Finally the symmetries of the effective field theories are used to find relations between non-perturbative matrix elements involved in "heavy to light" currents. AU - Campanario Pallás, Francisco DA - 2004 KW - quantum chromodynamics KW - heavy quark effective theory KW - heavy to light transitions LA - eng PY - 2004 TI - QCD aspects of heavy to light currents UR - https://nbn-resolving.org/urn:nbn:de:hbz:467-887 Y2 - 2024-12-26T07:14:25 ER -