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It is shown that the Thomas-Reiche-Kuhn sum rule, associated with the photoabsorption cross section from quantum systems, appears to be violated in the case of the quantized rigid rotator. The origin of the apparent violation is investigated, and its resolution is presented on the basis of a related system, i.e., a particle in a spherical ␦-function potential whose energy spectrum approaches that of the rigid rotator when the strength of the potential becomes large.

We explore the dependence of the magnetic and charge form factors of 'He and H on nucleon structure models and NN interaction models within the traditional framework of nucleons, isobars, and mesons. We utilize wave functions which incorporate the effect of a genuine three-body force, and include contributions to the nuclear current from a variety of mesonic exchange and isobaric processes. The importance of the high momentum transfer region as a source of information on short-range processes in the nuclear medium is reiterated by our results. NUCLEAR STRUCTURE Trinucleon systems; electromagnetic form factors; three-body force and mesonic exchange currents.

We report a single-step lithographic approach for precisely mapping near field light diffraction in photoresist and fabricating complex subwavelength structures. This method relies on the diffraction of UV light from opaque patterns on a photomask, and utilizes the central diffraction maximum (known as the 'Poisson spot' for an opaque disk) and its higher orders. By correlating pattern geometries with the resulting diffraction, we demonstrate that the near field light intensity can be quantified to high precision and is in good agreement with theory. The method is further extended to capture higher order diffraction, which is utilized to fabricate unconventional subwavelength nanostructures with three-dimensional topographies. The simplicity of this process and its capability for light mapping suggest it to be an important tool for near field optical lithography.