Effect of non-synchronous rotation on close binary stars

Nonsynchronous rotation effect on limiting surface of component star in close binarie

Rotating emission ring in binary systems

Rotating emission ring in terms of stability of periodic orbits in restricted three-body problem for binary system

On the mass-luminosity relation for galaxies

Relation between neutral hydrogen mass and luminosity for spiral and irregular galaxie

v4 for identified particles at RHIC from viscous hydrodynamics

Using ideal and viscous hydrodynamics, the ratio of azimuthal moments v4/(v2)^2 is calculated for pions, protons, and kaons in sqrt{s}=200 A*GeV Au+Au collisions. For any value of viscosity here is little dependence on particle species. Ideal hydrodynamics and data show a flat curve as a function of pt. Adding viscosity in the standard way destroys this flatness. However, it can be restored by replacing the standard quadratic ansatz for delta f (the viscous correction to the distribution function at freeze-out) with a weaker momentum dependence.Comment: Proceedings of Hot Quarks 2010, 21-26 June 2010 La Londe Les Maures, 4 pages, 2 figure

Optimal control of the heave motion of marine cable subsea-unit systems

One of the key problems associated with subsea operations involving tethered subsea units is the motions of support vessels on the ocean surface which can be transmitted to the subsea unit through the cable and increase the tension. In this paper, a theoretical approach for heave compensation is developed. After proper modelling of each element of the system, which includes the cable/subsea-unit, the onboard winch, control theory is applied to design an optimal control law. Numerical simulations are carried out, and it is found that the proposed active control scheme appears to be a promising solution to the problem of heave compensation

Calibrating dipolar interaction in an atomic condensate

We revisit the topic of a dipolar condensate with the recently derived more rigorous pseudo-potential for dipole-dipole interaction [A. Derevianko, Phys. Rev. A {\bf 67}, 033607 (2003)]. Based on the highly successful variational technique, we find that all dipolar effects estimated before (using the bare dipole-dipole interaction) become significantly larger, i.e. are amplified by the new velocity-dependent pseudo-potential, especially in the limit of large or small trap aspect ratios. This result points to a promising prospect for detecting dipolar effects inside an atomic condensate.Comment: 5 figures, to be publishe