Inside Touro Number 7

Sivan 3, 5756https://touroscholar.touro.edu/archives_books/1091/thumbnail.jp

The Different Effect of Electron-Electron Interaction on the Spectrum of Atoms and Quantum Dots

The electron-electron scattering rate of single particle excitations in atoms is estimated and compared with the corresponding rate in quantum dots. It is found that in alkali atoms single particle excitations do not acquire a width due to electron-electron interaction, while in complex atoms they may. This width is typically smaller than the single particle level spacing, and hence does not affect the number of discrete single particle excitations resolved below the ionization threshold. This situation is contrasted with that of quantum dots where electron-electron interaction severely limits the number of resolved excitations. Unlike the case of quantum dots, the scattering rate in atoms is found to decrease with increasing excitation energy. The different effect of electron-electron interaction on the spectrum of quantum dots and atoms is traced to the different confining potentials in the two systems.Comment: 12 pages including 2 eps figure

Spectral analysis of red scattered sunlight at sunrise

We analyze and fit visible spectra of a red horizon at sunrise. The shape of the spectra consist of a blue continuum followed by a red bump. The reddest spectra are well fitted by the product of a spectrum of extinguished sunlight (Rayleigh extinction + ozone absorption) and 1/lambda^4. The former is essentially the radiation field in the outer atmosphere, at the scattering volume location; the latter corresponds to Rayleigh scattering by the gas. Moving to higher altitudes, a second component, corresponding to the spectrum of a blue sky, must be added. The spectra we have obtained are similar to spectra of red nebulae, suggesting there may be other explanations than an emission process to the red color of some nebulae.Comment: 5 figure

Sport and exercise participation: motivation and barriers

Includes bibliographical references.Proceedings of the Sport Psychology Conference organised by the Centre for Physical Education and Sport, and the Physical Education and Sports Science Unit of the University of Hong Kong ; sponsored by the Hong Kong Sports Development Board.published_or_final_versionMotivation and the belief system Chan, Chin-ming, Roy Chan, Chin-ming, Roy 55Participation in sport and physical activity Seefeldt, Vern D. Seefeldt, Vern D. 1Participation in sport by students entering the University of Hong Kong: results of a survey undertaken in September 1993 Speak, Mike Speak, Mike Lindner, Koenraad Lindner, Koenraad Li, Daniel Li, Daniel 3Sports activities and the use of sports facilities in Hong Kong Sivan, Atara Sivan, Atara Robertson, Robert W. Robertson, Robert W. 19Factor impacting upon youth sport participation Shuttleworth, John Shuttleworth, John 25Factors affecting withdrawal reasons in youth sport Lindner, Koernaad Lindner, Koernaad Butcher, Janice Butcher, Janice Johns, David Johns, David 43Introduction to the conference Wells, Howard J. Wells, Howard J. viAnalyzing thought patterns in relation to sport performance and motivation McGill, J.O. Lewis McGill, J.O. Lewis 61The social-cognitive approach to motivation: practical implications for coaches and physical educators (abstract) Leahey, Trisha Leahey, Trisha 75Editor's note Lindner, K.J. Lindner, K.J. Speak, M.A. Speak, M.A. iiiConference contributors

Smashed hits: Overview

Though its trials are less monitored and recorded, music is no less subject to censorship than other forms of artistic expression, and the methods are much the same. These run the usual gamut from killing or imprisonment to banning the works themselves, and thence into that nebulous domain in which 'taste' and market forces are the engines of restriction