Electron correlation explored through electron spectrometry using synchrotron radiation

The development of synchrotron radiation facilities as a research tool has made possible experiments which provide new insights into the role which correlation plays in electron dynamics and atomic and molecular structure. Features such as autoionizing resonances, normal and resonant Auger decay modes, and ionization threshold structure have become visible in a wealth of new detail. Some aspects of this information drawn from recent experiments on the alkaline earth metals and the rare gases are presented. The potential for increased flux and resolution inherent in insertion device-based facilities like the Advanced Light Source should advance this understanding even further, and some future directions are suggested. 8 refs., 8 figs

Bullying and Victimization Among Boys and Girls in Middle School: The Influence of Perceived Family and School Contexts

The present study examines the mechanisms by which students\u27 perceptions of family and school experiences moderate the association between their emotionality and their habitual involvement in bullying and victimization. The authors hypothesize that students with internalizing and/or externalizing difficulties are less likely to be categorized as bullies and/or victims if they report coming from more cohesive and adaptable families and attending schools characterized by higher adult monitoring, lower levels of aggression and disorder, and higher levels of school bonding. Home and school environments in which these characteristics are less evident to students were expected to exacerbate the likelihood of being bullies and/or victims. Middle school youth (N = 2,506) and their teachers completed surveys assessing emotionality, peer relationships, academic performance, and home and school contexts. Using multinomial logistic regression, the authors found that perceived climates low in student misconduct increase the likelihood that internalizing difficulties predicted classification as victims. Increased student-reported adult monitoring decreased the likelihood for students with externalizing problems to be characterized as bullies, particularly for girls. These findings have implications for the development of school-based intervention programming

Letter of Intent to Build a MiniBooNE Near Detector:BooNE

There is accumulating evidence for a difference between neutrino and antineutrino oscillations at the {approx}1 eV{sup 2} scale. The MiniBooNE experiment observes an unexplained excess of electron-like events at low energies in neutrino mode, which may be due, for example, to either a neutral current radiative interaction, sterile neutrino decay, or to neutrino oscillations involving sterile neutrinos and which may be related to the LSND signal. No excess of electron-like events (-0.5 {+-} 7.8 {+-} 8.7), however, is observed so far at low energies in antineutrino mode. Furthermore, global 3+1 and 3+2 sterile neutrino fits to the world neutrino and antineutrino data suggest a difference between neutrinos and antineutrinos with significant (sin{sup 2} 2{theta}{sub {mu}{mu}} {approx} 35%) {bar {nu}}{sub {mu}} disappearance. In order to test whether the low-energy excess is due to neutrino oscillations and whether there is a difference between {nu}{sub {mu}} and {bar {nu}}{sub {mu}} disappearance, we propose building a second MiniBooNE detector at (or moving the existing MiniBooNE detector to) a distance of {approx}200 m from the Booster Neutrino Beam (BNB) production target. With identical detectors at different distances, most of the systematic errors will cancel when taking a ratio of events in the two detectors, as the neutrino flux varies as 1/r{sup 2} to a calculable approximation. This will allow sensitive tests of oscillations for both {nu}{sub e} and {bar {nu}} appearance and {nu}{sub {mu}} and {bar {nu}}{sub {mu}} disappearance. Furthermore, a comparison between oscillations in neutrino mode and antineutrino mode will allow a sensitive search for CP and CPT violation in the lepton sector at short baseline ({Delta}m{sup 2} > 0.1 eV{sup 2}). Finally, by comparing the rates for a neutral current (NC) reaction, such as NC {pi}{sup 0} scattering or NC elastic scattering, a direct search for sterile neutrinos will be made. The initial amount of running time requested for the near detector will be a total of {approx}2E20 POT divided between neutrino mode and antineutrino mode, which will provide statistics comparable to what has already been collected in the far detector. A thorough understanding of this short-baseline physics will be of great importance to future long-baseline oscillation experiments

The fourth moment in Luby's distribution

Luby (1988) proposed a way to derandomize randomized computations which is based on the construction of a small probability space whose elements are 3-wise independent. In this paper we prove some new properties of Luby's space. More precisely, we analyze the fourth moment and prove an interesting technical property which helps to understand better Luby's distribution. As an application, we study the behavior of random edge cuts in a weighted graph. (orig.)SIGLEAvailable from TIB Hannover: RR 1912(95-1-019) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekCommission of the European Communities, Brussels (Belgium). European Programme for Research and Development in Information Technology (ESPRIT); Ministry of Education, Athens (Greece)DEGerman