Dual Principles in Maximum Entropy Reconstruction of the Wave Distribution Function

Maximum entropy methods are used for reconstructing the distribution of energy in wave vector space from frequency spectra observed on board satellites. The reconstruction scheme is based on a modified entropy function, and dual principles are used to solve the resulting optimization problem. Our scheme is not limited to reconstructions of wave distribution functions, but it should be useful also for solving other types of underdetermined inverse problems.     

Enzymatic resolution of substituted mandelic acids

A series of substituted mandelic acids were prepared and subjected to enzymatic resolution utilizing Lipase PS ‘Amano’.     

Predictions for anomalous τ+τ−γ production at LEP 1

We calculate distributions for τ⁺τ^?γ production at LEP 1 taking into account a potentially existing anomalous magnetic moment a _τ of the τ lepton. The existing upper limits for ¦a _τ¦ are known from the dependence of the decay Z ⁰ → τ⁺τ^?γ on a _τ ² and are of the order of (1–5)%. We show that such limits are also sensitive to linear terms in a _τ, which are of equal importance at ¦a _τ¦ ～ (1–2)% and dominate below this value. Contributions from an electric dipole moment dτ do not interfere with the electromagnetic vertex or with the anomalous magnetic moment. Appropriate formulae are derived.     

A Note on Capacity and Hausdorff Measure in Homogeneous Spaces

ggt We consider analogoues of classical Riesz capacity C and Hausdorff measure H in a homogeneous space (X,d,µ) . We prove that, under mild regularity conditions on (X,d,µ), the usual relations between C and H hold. The key step in the proof is a version of the so called Frostman Lemma in a homogeneous space.     

Intrinsic Josephson junctions in Bi2Sr2CaCu2O8+δ single crystals

We report on thec-axis superconducting energy gap parameter Δ _c (T) of intrinsic Josephson tunnel junctions inBi ₂ Sr ₂ CaCu ₂ O _8+δ (Bi2212) single crystals. Δ _c (4.2K)≈10−13 meV, which is approximately a factor of two smaller than reported in the majority of tunneling experiments. Δ _c (T) deviates strongly from the BCS temperature dependence. These observations may be explained by a multilayer model of Bi2212 which assumes that theBi−O layers are superconducting due to the proximity effects. The Josephson tunneling then takes place between adjacentBi−O layers while there is a strong proximity coupling betweenBi−O andCu−O layers. The work is supported by Swedish Supercon-ductivity Consortium and NUTEK, and, in part, by Russian Foundation for Basic Research, grant #95-02-04307     

Model Independent QED Corrections to the Process ep → eX

We give an exhaustive presentation of the semi-analytical approach to the model independent leptonic QED corrections to deep inelastic neutral current lepton-nucleon scattering. These corrections include photonic bremsstrahlung from and vertex corrections to the lepton current of the order φ(α) with soft photon exponentiation. A common treatment of these radiative corrections in several variables — leptonic, hadronic, mixed, Jaquet-Blondel variables — has been developed and double differential cross sections are calculated. In all sets of variables we use some structure functions, which depend on the hadronic variables and which do not have to be defined in the quark parton model. The remaining numerical integrations are twofold (for leptonic variables) or onefold (for all other variables). For the case of hadronic variables, all phase space integrals have been performed analytically. Numerical results are presented for a large kinematical range, covering fixed target as well as collider experiments at HERA or LEP⊗LHC, with a special emphasis on HERA physics.