Topological Superfluid Transition Induced by Periodically Driven Optical Lattice

We propose a scenario to create topological superfluid in a periodically driven two-dimensional square optical lattice. We study the phase diagram of a spin-orbit coupled s-wave pairing superfluid in a periodically driven two-dimensional square optical lattice. We find that a phase transition from a trivial superfluid to a topological superfluid occurs when the potentials of the optical lattices are periodically changed. The topological phase is called Floquet topological superfluid and can host Majorana fermions.Comment: 6 pages, 1 figure

Quantitative Assessment of Flame Stability Through Image Processing and Spectral Analysis

This paper experimentally investigates two generalized methods, i.e., a simple universal index and oscillation frequency, for the quantitative assessment of flame stability at fossil-fuel-fired furnaces. The index is proposed to assess the stability of flame in terms of its color, geometry, and luminance. It is designed by combining up to seven characteristic parameters extracted from flame images. The oscillation frequency is derived from the spectral analysis of flame radiation signals. The measurements involved in these two methods do not require prior knowledge about fuel property, burner type, and other operation conditions. They can therefore be easily applied to flame stability assessment without costly and complex adaption. Experiments were carried out on a 9-MW heavy-oil-fired combustion test rig over a wide range of combustion conditions including variations in swirl vane position of the tertiary air, swirl vane position of the secondary air, and the ratio of the primary air to the total air. The impact of these burner parameters on the stability of heavy oil flames is investigated by using the index and oscillation frequency proposed. The experimental results obtained demonstrate the effectiveness of the methods and the importance of maintaining a stable flame for reduced NOx emissions. It is envisaged that such methods can be easily transferred to existing flame closed-circuit television systems and flame failure detectors in power stations for flame stability monitoring

Magnetic moments of the spin-32{3\over 2} doubly heavy baryons

In this work, we investigate the chiral corrections to the magnetic moments of the spin-$3\over 2$ doubly charmed baryons systematically up to next-to-next-to-leading order with the heavy baryon chiral perturbation theory. The numerical results are given up to next-to-leading order: $\mu_{\Xi^{*++}_{cc}}=1.72\mu_{N}$, $\mu_{\Xi^{*+}_{cc}}=-0.09\mu_{N}$, $\mu_{\Omega^{*+}_{cc}}=0.99\mu_{N}$. As a by-product, we have also calculated the magnetic moments of the spin-$3\over 2$ doubly bottom baryons and charmed bottom baryons: $\mu_{\Xi^{*0}_{bb}}=0.63\mu_{N}$, $\mu_{\Xi^{*-}_{bb}}=-0.79\mu_{N}$, $\mu_{\Omega^{*-}_{bb}}=0.12\mu_{N}$, $\mu_{\Xi^{*+}_{bc}}=1.12\mu_{N}$, $\mu_{\Xi^{*0}_{bc}}=-0.40\mu_{N}$, $\mu_{\Omega^{*0}_{bc}}=0.56\mu_{N}$.Comment: 10 pages,2 figures. arXiv admin note: text overlap with arXiv:1707.02765. Replace the published versio

Radiative decays of the doubly charmed baryons in chiral perturbation theory

We have systematically investigated the spin-$\frac{3}{2}$ to spin-$\frac{1}{2}$ doubly charmed baryon transition magnetic moments to the next-to-next-to-leading order in the heavy baryon chiral perturbation theory (HBChPT). Numerical results of transition magnetic moments and decay widths are presented to the next-to-leading order: $\mu_{\Xi_{cc}^{*++}\rightarrow\Xi_{cc}^{++}}=-2.35\mu_{N}$, $\mu_{\Xi_{cc}^{*+}\rightarrow\Xi_{cc}^{+}}=1.55\mu_{N}$, $\mu_{\Omega_{cc}^{*+}\rightarrow\Omega_{cc}^{+}}=1.54\mu_{N}$, $\Gamma_{\Xi_{cc}^{*++}\rightarrow\Xi_{cc}^{++}}=22.0$ keV, $\Gamma_{\Xi_{cc}^{*+}\rightarrow\Xi_{cc}^{+}}=9.57$ keV, $\Gamma_{\Omega_{cc}^{*+}\rightarrow\Omega_{cc}^{+}}=9.45$ keV.Comment: arXiv admin note: text overlap with arXiv:1707.02765, arXiv:1706.0645