Twisted mass QCD (tmQCD) has been introduced as a solution to the problem of unphysical fermion zero modes in lattice QCD with quarks of the Wilson type. We here argue that O(a) improvement of the tmQCD action and simple quark bilinear operators can be more economical than in the standard framework. In particular, an improved and renormalized estimator of the pion decay constant in two-flavour ...

One of the most important questions, especially in applications, is how to choose a decay function in the study of stability for a concrete equation. Motivated by the fact that the coefficients of the considered equation mainly suggest the choice of the decay function, the point of analysis in the paper is to carry out the Lyapunov function approach and to state coercivity conditions dependent ...

We study the low energy dynamics of pions in a gravity dual of chiral symmetry breaking. The string theory construction consists of a probe D7 brane in the Constable Myers non-supersymmetric background, which has been shown to describe chiral symmetry breaking in the pattern of QCD. We expand the D7 brane’s Dirac Born Infeld action for fluctuations that correspond to the Goldstone mode and show...

The electroweak penguin mediated B → Xsll decay is a good probe to study beyond the Standard Model physics at low energy. The effect of new physics could be observed as corrections to the branching fraction, di-lepton invariant mass spectrum, and to the Wilson coefficients such as C9, C10, and a phase of C7 [1-10]. Experimentally, the exclusive B → Kll decay was observed by the Belle collaborat...

We investigate scattering, localization and dispersive time-decay properties for the onedimensional Schrödinger equation with a rapidly oscillating and spatially localized potential, q = q(x, x/ ), where q(x, y) is periodic and mean zero with respect to y. Such potentials model a microstructured medium. Homogenization theory fails to capture the correct lowenergy (k small) behavior of scatterin...

Alder and Wainwright discovered the slow power decay ~t(-d/2) (d is dimension) of the velocity autocorrelation function in moderately dense hard-sphere fluids using the event-driven molecular dynamics simulations. In the two-dimensional (2D) case, the diffusion coefficient derived using the time correlation expression in linear response theory shows logarithmic divergence, which is called the "...

G. I. Taylor [ 1 ] showed that the flow representing a double array of vortices which has the same periodicity in both the x and y directions is a solution to the equations of motion in two dimensions of a linearly viscous fluid. It was shown in [2] that such a result is also true for 'second order' fluids if time scale which characterizes the memory of the fluid and the size of the vortices sa...

The flavor changing neutral current processes KL → π0e+e−, B → Xsee and B → Xsμμ are studied within the minimal supersymmetric extension of the Standard Model. We first examine the rates for these decay modes in the MSSM with a universal soft supersymmetry breaking sector at a Grand Unification scale. We later relax the universality condition and investigate the FCNC transitions in a more gener...

The mechanism of the thiol-ene reaction induced by 330 nm ultraviolet excitation of 1,2-di(quinolin-2-yl)disulfide (QSSQ) in the presence of methyl methacrylate (MMA) is investigated by sub-picosecond to microsecond transient absorption spectroscopy. The measurements, spanning more than seven orders of magnitude of time, directly reveal multiple radical reaction steps. The ground state quinolie...

This paper is concerned with exponential estimates and stabilization of a class of discrete-time singular systems with time-varying state delays and saturating actuators. By constructing a decay-rate-dependent Lyapunov-Krasovskii function and utilizing the slow-fast decomposition technique, an exponential admissibility condition, which not only guarantees the regularity, causality, and exponent...