arXiv subjects

Berthold Stech

Publications and source records attributed to Berthold Stech.

22 records · Page 2Linked to original sources

arXiv1997

Non-Leptonic Weak Decays of B Mesons

We present a detailed study of non-leptonic two-body decays of B mesons based on a generalized factorization hypothesis. We discuss the structure of non-factorizable corrections and present arguments in favour of a simple phenomenological description of their effects. To evaluate the relevant transition form factors in the factorized decay amplitudes, we use information extracted from semileptonic decays and incorporate constraints imposed by heavy-quark symmetry. We discuss tests of the factorization hypothesis and show how unknown decay constants may be determined from non-leptonic decays. In particular, we find f_{Ds}=(234+-25) MeV and f_{Ds*}=(271+-33) MeV.

hep-ph↗

arXiv1997

A Second Look at Masses and Mixings of Quarks and Leptons

The masses of quarks and leptons in units of $m_t$ are expressed in powers of $σ=\sqrt{m_c/m_t}$. The regularities found suggest specific mass matrices. They reproduce all masses and mixings in striking agreement with observation. A 90 degree relative phase angle between the off-diagonal elements of up and down quark matrices leads to a maximum magnitude for CP-violation and, for the phase angle $γ$ of the unitary triangle, to $γ\simeq 90^o$.

hep-ph↗

arXiv1996

A Form Factor Model for Exclusive B- and D-Decays

An explicit model is presented which gives the momentum transfer-dependent ratios of form factors of hadronic currents. For the unknown Isgur-Wise function and its generalization for transitions to light particles a simple phenomenological Ansatz is added. The model allows a calculation of all form factors in terms of mass parameters only. It is tested by comparison with experimental data, QCD sum rules and lattice calculations.

hep-ph↗

arXiv1995

Form Factor Relations for Heavy-to-Light Transitions

Assuming simple properties of the spectator particle in weak decays the form factors of hadronic current matrix elements are shown to be related to a single universal function. The Isgur-Wise result for heavy-to-heavy transitions follows as well as similar relations for heavy-to-light decay processes. The approximation should hold for total energies of the final particle large compared to the confinement scale. A comparison with experimentally determined D-decay form factors and QCD sum rule results for B-decays is very encouraging.

hep-ph↗