Is the axial anomaly really determined in a continuous non-perturbative regularization?

In the framework of a gauge invariant continuous and non-perturbative regularization scheme based on the smearing of point like interactions by means of cutoff functions, we show that the axial anomaly, though cutoff independent, depends on the shape of the cutoff functions. The standard value for the strength of the axial anomaly is recovered if we assume that the regularized gauge invariant axial current is in addition local.Comment: 12 pages, 1 figure, some typos corrected, to be published in European Physical Journal

Path integral regularization of pure Yang-Mills theory

In enlarging the field content of pure Yang-Mills theory to a cutoff dependent matrix valued complex scalar field, we construct a vectorial operator, which is by definition invariant with respect to the gauge transformation of the Yang-Mills field and with respect to a Stueckelberg type gauge transformation of the scalar field. This invariant operator converges to the original Yang-Mills field as the cutoff goes to infinity. With the help of cutoff functions, we construct with this invariant a regularized action for the pure Yang-Mills theory. In order to be able to define both the gauge and scalar fields kinetic terms, other invariant terms are added to the action. Since the scalar fields flat measure is invariant under the Stueckelberg type gauge transformation, we obtain a regularized gauge-invariant path integral for pure Yang-Mills theory that is mathematically well defined. Moreover, the regularized Ward-Takahashi identities describing the dynamics of the gauge fields are exactly the same as the formal Ward-Takahashi identities of the unregularized theory.Comment: LaTeX file, 24 pages, improved version, to be published in Phys. Rev.

Optimal Cantilever Dynamic Vibration Absorbers

This work considers the use of a double-ended cantilever beam as a distributed parameter dynamic vibration absorber applied to a single-degree-of-freedom system in the presence of sinusoidal forces. The problem is analyzed exactly and by an energy approach using a single mode approximation for the cantilever beam. The results for both techniques compare favorably and damping is introduced in the form of a complex beam modulus. Optimal tuning and optimal damping parameters are found for a given ratio of absorber mass to main mass. © 1977 by ASME

Mise en ligne d'un microscope digitalisé et télécommandé

On décrit la mise en ligne avec un calculateur d'un microscope digitalisé en x, y, z, et télécommandé, pour les mesures dans l'émulsion ionographique

A Preliminary Checklist of the Moths of Butler County, Ohio

Author Institution: Department of Zoology, Miami UniversityUsing a combination of blacklight, mercury vapor light, and sugar bait sampling techniques, we collected moths over a 2-yr period in Butler County, OH, and compiled a list of 392 species. Seventy-eight percent (305) of these species were found to be new county records. A checklist is provided as a baseline catalogue of the moths of Butler County, OH. An analysis of historical county records revealed a bias towards large or colorful species. Although many species we collected are considered common, several infrequently encountered species were discovered. Our effort suggests that biological surveys in fragmented landscapes may reveal unexpected biological diversity