Symmetry limit properties of a priori mixing amplitudes for non-leptonic and weak radiative decays of hyperons

We show that the so-called parity-conserving amplitudes predicted in the a priori mixing scheme for non-leptonic and weak radiative decays of hyperons vanish in the strong-flavor symmetry limit

Self-Dual Vortices in Abelian Higgs Models with Dielectric Function on the Noncommutative Plane

We show that Abelian Higgs Models with dielectric function defined on the noncommutative plane enjoy self-dual vorticial solutions. By choosing a particular form of the dielectric function, we provide a family of solutions whose Higgs and magnetic fields interpolate between the profiles of the noncommutative Nielsen-Olesen and Chern-Simons vortices. This is done both for the usual $U(1)$ model and for the $SU(2)\times U(1)$ semilocal model with a doublet of complex scalar fields. The variety of known noncommutative self-dual vortices which display a regular behaviour when the noncommutativity parameter tends to zero results in this way considerably enlarged

State selection in the noisy stabilized Kuramoto-Sivashinsky equation

In this work, we study the 1D stabilized Kuramoto Sivashinsky equation with additive uncorrelated stochastic noise. The Eckhaus stable band of the deterministic equation collapses to a narrow region near the center of the band. This is consistent with the behavior of the phase diffusion constants of these states. Some connections to the phenomenon of state selection in driven out of equilibrium systems are made.Comment: 8 pages, In version 3 we corrected minor/typo error

I-V curves and intergranular flux creep activation energy in the magnetic superconductor RuSr2GdCu2O8

A systematic study of I-V characteristic curves for RuSr2GdCu2O8 [Ru-(1212)] is presented, with magnetic fields up to 3 T and 5 K<T<30 K, in the region of the superconducting transition. The activation energy E_{a}(H,T) for flux line depinning was determined by fitting the nonlinear region of the curves using the flux creep model. E_{a}(H,T) was found to vary linearly with temperature, while a power-law dependence on the magnetic field was observed up to H=0.1 T, where an abrupt reduction in its decreasing rate occurs. The extrapolated value, E_{a}(0,0)=50 meV, is twice the reported value for YBa2Cu3O7, but the critical current density J_{C}(0,0)=70 A/cm2 is about one order of magnitude lower. These results are explained as a consequence of the contribution of the magnetization in the grains to the effective field at the intergranular links and to a spin-flop transition of the Ru-sub-lattice.Comment: 4 pages, 3 figure

Adaptive Coordination of Distributed Energy Resources in Lossy Power Distribution Systems

This paper is concerned with the problem of coordinating a set of distributed energy resources (DERs) in a lossy power distribution system to provide frequency regulation services to a bulk power grid with the explicit consideration of system losses. To this end, we formulate the problem as an optimization problem, the objective of which is to minimize some cost function subject to a set of constraints. The formulation requires knowledge of incremental total system losses, which we approximate using the so-called loss factors (LFs) that explicitly capture the impacts of both active and reactive power injections on system losses. The LFs are estimated recursively using power injection measurements; thus, they are adaptive to various phenomena that impact the power system operation. Numerical simulation on a 33-bus distribution test feeder validated the effectiveness of the proposed framework