It was recently pointed out that the decays B + → D * + s γ and B + → D * + γ can be used for an extraction of |V ub |. The theory of these decays is poorly understood. It was shown that in a world of almost degenerate b and c-quarks the decay would be computable. The severe difficulties that are encountered in the realistic calculation stem primarily from the very hard photon produced in the two body decay. We point out that in the decays B + → D * + s e + e − and B + → D * + e + e − the photon vertex is soft when the charmed meson is nearly at rest (in the B + rest frame). This allows us to compute with some confidence the decay rate in a restricted but interesting kinematic regime. Given enough data the extraction of V ub with reasonably small uncertainties could proceed through an analysis of these exclusive decays much as is done in the determination of V cb .12.15. Hh, 12.39.Hg, 13.40.Hq, 13.25.Hw

The decays B + → D * + s γ and B + → D * + γ can be used for an extraction of |V ub |. When the b and c quarks are nearly degenerate the rate for these modes can be determined in terms of other observed rates, namely BB mixing and D * → Dγ decay. To this end we introduce a novel application of heavy quark and flavor symmetries. Although somewhat unrealistic, this limit provides us with a first estimate of these rates.12.15. Hh, 12.39.Hg, 13.40.Hq, 13.25.Hw

The effective Lagrangian and power counting rules for non-relativistic gauge theories are derived via a systematic expansion in the large c limit. It is shown that the 1/c expansion leads to an effective field theory which incorporates a multipole expansion. Within this theory there is no need for heuristic arguments to determine the scalings of operators. After eliminating c from the lowest order Lagrangian the states of the theory become independent of c and the scaling of an operator is given simply by its overall coefficient. We show how this power counting works in the calculation of the Lamb shift within the effective field theory formalism.

A systematic approach to long-distance effects in exclusive radiative weak B decays is presented, based on a combination of the heavy quark limit with perturbative QCD. The dominant long-distance effects, connected with weak annihilation and W-exchange topologies, can be computed in a model-independent way using experimental data on B radiative leptonic decays. Nonfactorizable corrections vanish in the chiral limit and to leading twist. The left-handed photon amplitudes are shown to be enhanced relative to the right-handed ones, both in the long-and short-distance parts of the B decay amplitudes. Recent CLEO data on B→K*␥ decays are consistent with standard model estimates of the long-distance contributions, and disfavor an enhanced gluonic penguin contribution. We discuss the implications of our results for the extraction of ͉V td ͉.

We begin the process of classifying all supersymmetric theories with quantum modified moduli. We determine all theories based on a single SU or Sp gauge group with quantum modified moduli. By flowing among theories we have calculated the precise modifications to the algebraic constraints that determine the moduli at the quantum level. We find a class of theories, those with a classical constraint that is covariant but not invariant under global symmetries, that have a singular modification to the moduli, which consists of a new branch. 11.30. Pb, 11.15.Tk Typeset using REVT E X