The approach of generalized collective modes is applied to the study of dispersion curves of collective excitations along isothermal lines of supercritical pure Lennard-Jones fluid. An effect of structural relaxation and other nonhydrodynamic relaxation processes on the dispersion law is discussed. A simple analytical expression for the dispersion law in the long-wavelength region of acoustic e...

The dependence of the velocity surface acoustic waves (SAWs) as a function an external applied magnetic field is investigated in $\mathrm{Fe}$ thin film epitaxially grown on piezoelectric $\mathrm{Ga}\mathrm{As}$ substrate. SAW observed to strongly depend both amplitude and direction field. To interpret experimental data phenomenological approach relative change implemented. We find that variat...

The rich correlation physics in two-dimensional (2D) electron systems is governed by the dispersion of its excitations. In the fractional quantum Hall regime, excitations involve fractionally charged quasi particles, which exhibit dispersion minima at large momenta referred to as rotons. These rotons are difficult to access with conventional techniques because of the lack of penetration depth o...

EMA, aerodynamic, and acoustic signals were combined in order to observe lingual and labial articulation of oral and nasal vowels in Northern Metropolitan French (NMF) and Quebec French (QF). Inter-speaker variation observed in oral articulation suggests the importance of motor equivalence in the acoustic dispersion of each vowel system. Inter-dialectal differences observed are suggestive of im...

Theoretical and experimental studies of low-frequency electrostatic waves in plasmas containing negatively charged dust grains are described. The presence of charged dust is shown to modify the properties of ion-acoustic waves and electrostatic ion-cyclotron waves through the quasineutrality condition even though the dust grains do not participate in the wave dynamics. If the dust dynamics is i...

The mean flow stability of a Mach 0.9 turbulent jet is investigated by means of global linear theory with a focus on acoustic effects. A novel class of resonant acoustic modes that are trapped within the potential core, and whose eigenvalues appear as discrete branches in the global stability spectrum, is studied in detail. A dispersion relation is reconstructed from the global modes, and shown...