Starting from a complete operator product expansion up to mass dimension-6 twist4 and up to first order in the coupling constants we investigate the splitting and mixing of ρ and ω mesons in isospin symmetric nuclear matter. Special attention is devoted to the impact of the scalar 4-quark condensates on both effects. In nuclear matter the Landau damping governs the ρ−ω mass splitting while the ...

A search for squarks of R-parity violating supersymmetry is performed in ep collisions at HERA using H1 1994!1997 data corresponding to an integrated luminosity of 37 pb 1. Direct single production of squarks of each generation by e+-quark fusion via a Yukawa coupling 0 is considered and various possible R-parity violating decays and gauge decays of the squarks are taken into account. Such coup...

We show that the effective coupling constants τ of supersymmetric gauge theories described by hyperelliptic curves do not distinguish between the lattices of the two kinds of heterotic string. In particular, the following relation ΘD+ 16 (τ) = Θ2E8(τ) holds. This is reminiscent of the relation, by T -duality, of the two heterotic strings. We suggest that such a relation extends to all curves de...

Inspired by split supersymmetry, we study a minimal supersymmetric scenario with only the Higgsino mass parameter μ below the TeV scale. The motivation is to satisfy the gauge coupling unification and dark matter constraints with the minimal particle contents at the electroweak scale in supersymmetric models. With the neutral Higgsino as the lightest supersymmetric particle, we discuss the dark...

Inspired by recent claims for a varying fine structure constant, alpha, we investigate the effect of “promoting coupling constants to variables” upon various parameters of the standard model. We first consider a toy model: Proca’s theory of the massive photon. We then explore the electroweak theory with one and two dilaton fields. We find that a varying alpha unavoidably implies varying W and Z...

The status of the calculation of next-to-leading-order QCD corrections to hadronic final states in deeply inelastic scattering is reviewed, and an overview of the phenomenology (including the measurement of the strong coupling constant and the gluon density via jet rates) is given. We also describe a new universal program (DISASTER++) for the calculation of (2+1)-jet observables.

Let H be the Stark operator in R3 and let V = V (x) be a non-negative potential which decays at infinity as |x|−l for a sufficiently large l > 0. The spectral shift function for the pair of operators H + tV , H is studied in the asymptotic regime t →∞. The leading term of the asymptotics is obtained; the result is in agreement with the phase space volume considerations.

Because strong interactions are flavourindependent, it would appear that they can be equally well studied in the spectroscopy of light or heavy quarks. However, the highly relativistic nature of quarks in light-quark (u, d, s) hadrons, the large value of the strong coupling constant, αs (& 0.6), and the near equality of the masses of the u, d, s quarks, makes the light quark states strongly ove...

This talk discusses the relative impact of running-coupling and other higher-order corrections on the small-x gluon-gluon splitting function. Comments are made on similarities with some aspects of the Balitsky-Kovchegov equation, which arise because of the presence of an effective infrared cutoff in both cases. It is emphasised that, at least in the splitting-function case, the asymptotic small...

This paper aims at proposing a measure of speech rhythm based on the inference of the coupling strength between the syllable oscillator and the stress group oscillator of an underlying coupled oscillators model. This coupling is inferred from the linear regression between the stress group duration and the number of syllables within the group, as well as from the multiple linear regression betwe...