Search

We describe nuclear effects in structure functions of nuclei in DIS by means of a multiplicative factor β A (x) which differentiates the structure function of the bound nucleons from that of the free nucleons. Our analysis determines that β A (x) establishes a relation between the quark-gluon dynamics expressed by the bound nucleon structure functions and the nuclear dynamics as described by the well-known semi-empirical Bethe-Weizsäcker mass formula. This relation corroborates a connection between the underlying quark-gluon dynamics and the phenomenological nuclear dynamics. [ABSTRACT FROM AUTHOR]

The Hannay geometric phase is the classical analog of the well-known Berry phase. Its most familiar example is the effect of the latitude λ on the motion of a Foucault pendulum. We describe an electronic network whose behavior is exactly equivalent to that of the pendulum. The circuit can be constructed from off-the-shelf components using two matched transconductance amplifiers that comprise a gyrator to introduce the non-reciprocal behavior needed to mimic the pendulum. One may precisely measure the dependence of the Hannay phase on λ by circuit simulation and by laboratory measurements on a constructed circuit. [ABSTRACT FROM AUTHOR]

We show that due to the large coupling constant of the monopole-photon interaction the annihilation of monopole-antimonopole and monopolium into many photons must be considered experimentally. For monopole-antimonopole annihilation and lightly bound monopolium, even in the less favorable scenario, multiphoton events (four and more photons in the final state) are dominant, while for strongly bound monopolium, although two photon events are important, four- and six-photon events are also sizable. [ABSTRACT FROM AUTHOR]

We study nuclear effects in the deuteron in the deep inelastic regime using the newest available data. We put special emphasis on their $Q^{2}$ dependence. The study is carried out using a scheme which parameterizes, in a simple manner, these effects by changing the proton and neutron stucture functions in medium. The result of our analysis is compared with other recent proposals. We conclude that precise EMC ratios cannot be obtained without considering the nuclear effects in the deuteron. [ABSTRACT FROM AUTHOR]

An interesting analog circuit for simulating a signal with fluctuations having a probability density function with a power tail has recently been proposed and constructed. The exponent of the power law can be fixed by tuning an appropriate circuit element. The proposal is to use the circuit as a simulator-generator of financial market fluctuations and as a tool for risk estimations and forecasts. We present a discussion of the stability conditions for multiplicative noise and an exhaustive analysis of the power law fluctuation generator in connection with the electronic components and their parameters. From our studies, one can conclude that the proposal is not adequate to provide a confident experimental scheme to follow the fluctuations of the financial market due to both electronic implementation and to difficulties in parameter tuning. [ABSTRACT FROM AUTHOR]

Time series corresponding to nominal exchange rates between the US dollar and Argentina, Brazil and European Economic Community currencies; different financial indexes as the Industrial Dow Jones, the British Footsie, the German DAX Composite, the Australian Share Price and the Nikkei Cash and also different Argentine local tax revenues, are analyzed looking for the appearance of simple patterns and the possible definition of forecast evaluators. In every case, the statistical fractal dimensions are obtained from the behavior of the corresponding variance of increments at a given lag. The detrended fluctuation analysis of the data in terms of the corresponding exponent in the resulting power law is carried out. [ABSTRACT FROM AUTHOR]

The spin correlated angular distribution for ττ pairs at energies of the Z resonance, both decaying semi-leptonically up to 3 hadrons in each final state, was derived assuming general vector and axial vector couplings. The use of these distributions to test the V-A structure of the τ- W- v vertex at LEP energies is analized. [ABSTRACT FROM AUTHOR]

An extremely simple but instructive, 'toy' model is presented which shows that a small excess of pions in the nucleus can produce a significant change in the values expected for the Gottfried sum rule. The general question of the convergence of the sum rule and of the convergence of the experimental integral is also discussed. It is demonstrated that conclusions about the sum rule, based on deuterium data, are surprisingly model dependent. In contrast, it is stressed, that the Bjorken sum rule can be tested significantly using deuterium data. [ABSTRACT FROM AUTHOR]

Data on multiplicity distributions in p $$\bar b$$ collisions at 0.3, 0.546, 1.0 and 1.8 GeV CM energy from recent experiments at FNAL and its relation to previous experiments are analyzed. Fits to the data and a critical discussion of the results are presented. [ABSTRACT FROM AUTHOR]

Recent data on Drell-Yan processes induced by protons on nuclear targets gives non trivial information about nuclear effects. A very simple model for excess pions in nuclei reproduces the main features of these data, and also of those comming from deep inelastic experiments. This simple scheme gives an unified treatement of nuclear effects highlighting its importance in the deuteron and provides a precise prediction for future p-p and p-d Drell-Yan experiments. [ABSTRACT FROM AUTHOR]

Copyright of Il Nuovo Cimento: A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)