ar X iv : h ep - p h / 03 05 33 5 v 1 3 0 M ay 2 00 3 Nonfactorizable contributions to B → D ( ∗ ) M decays

ar X iv : h ep - p h / 03 05 33 5 v 3 1 1 Fe b 20 05 Nonfactorizable contributions to B → D ( ∗ ) M decays

While the naive factorization assumption works well for many two-body nonleptonic B meson decay modes, the recent measurement of B̄ → D(∗)0M0 withM = π, ρ and ω shows large deviation from this assumption. We analyze the B → D(∗)M decays in the perturbative QCD approach based on kT factorization theorem, in which both factorizable and nonfactorizable contributions can be calculated in the same fr...

ar X iv : h ep - p h / 02 10 35 3 v 1 2 5 O ct 2 00 2 Nonfactorizable effects in B → J / ψK

The method of QCD light-cone sum rules is used to calculate soft nonfactorizable contributions to the decay amplitude for B → J/ψK. The result confirms expectations that in color-suppressed decays nonfactorizable corrections can be sizable.

ar X iv : h ep - p h / 04 05 03 9 v 1 5 M ay 2 00 4 η , η ′ → π + π − γ with coupled channels

ar X iv : h ep - p h / 01 05 03 3 v 1 3 M ay 2 00 1 Threshold η and η ′ electroproduction off nucleons 1

The electroproduction of η and η ′ mesons on the proton and the neutron is investigated at tree level within the framework of U (3) chiral perturbation theory. In addition to the Born terms low-lying resonances such as the vector mesons and J P = 1/2 + , 1/2 − baryon resonances are included explicitly and their contributions are calculated. Results for the separated differential cross sections ...

ar X iv : h ep - p h / 03 05 16 5 v 1 1 5 M ay 2 00 3 The rise and fall of F 2 at low x

A short personal account is given of the impact of HERA data and the influence of Jan Kwiecinski on low x physics.