Observation of soft-x-ray spatial coherence from resonance transition radiation

We have observed the spatial distribution of coherent or resonant transition radiation (RTR) in the soft-x-ray region of the spectrum (1-2 keV). Resonance transition radiators were constructed and tested at two accelerators using electron-beam energies ranging from 50 to 228 MeV. These radiators emitted soft x-rays in a circularly symmetrical annulus with a half-angle divergence of 2.5-9.0 mrad. The angle of peak emission was found to increase with electron-beam energy, in contrast to the incoherent case, for which the angle of emission varied inversely with electron-beam energy. By careful selection of foil thickness and spacing, one may design radiators whose angle of emission varies over a range of charged-particle energies. A particular RTR mode (r=m=1) was found to give a sharp annular ring that becomes more accentuated as the number of foils is increased. The RTR effect has application in particle detection, beam diagnostics, x-ray source brightness enhancement, and x-ray free-electron-laser emission.This work was supported by the Department of Energy under the Small Business Innovative Research (SBIR) program, Grant Number DE-AC03-86ER80428, Canadian Natural Science and Engineering Research Council (NSERC), and the Naval Postgraduate SchoolApproved for public release; distribution is unlimited

The Canadian Light Source: An Update

The Canadian Light Source (CLS) is now under construction. It will be a third generation source capable of producing photon beams for a variety of research applications. The CLS has four principal components: a 250 MeV linac, a full energy booster, a storage ring, and an array of beam lines serving interests ranging from infrared light to hard x-rays. The 2.9 GeV storage ring has a compact design made up of twelve double bend achromats incorporating twelve 5 m straights for injection, RF and insertion devices (IDs). RF power for the storage ring will be supplied by a single superconducting cell operating at 500 MHz. Construction and commissioning should be complete by the end of 2003 and an initial complement of five IDs and three bend magnet sources supplying light to eight beam lines and eleven experimental end stations is anticipated. Photon beams with high brightness will be achieved through a combination of low electron beam emittance (18 nm-rad), high circulating current (500 mA), small vertical coupling and a variety of undulator magnets. The use of small gap undulators will result in bright beams at photon energies up to 20 keV

The cultural evolution of talent management: a memetic analysis

Using the concept of memes as cultural transmitters and replicators, this article explores the origins of a talent meme and the subsequent evolution of talent management (TM). The sociogenesis of TM is traced through historic developments in management thinking. The rise of individualism in the late 20th century created the conditions for the birth of TM, and the proliferation of the meme since birth is analyzed. The meme reproduces through its psychological appeal and the logic of itself, and the article uses an established approach to reveal cultural rather than rational explanations for TM. Five reasons for the attractiveness, survival, and replication of the talent meme in business organizations are identified. They are salience with business conditions, lack of a competing meme, ambiguity, complexity reduction, and enhanced control over a powerful group. Understanding more about the psychological attractors attached to the talent meme forms part of an expanded research agenda