Effect of nonlinear perturbations on second order linear nonoscillatory differential equations

The aim of this paper is to show that any second order nonoscillatory linear differential equation can be converted into an oscillating system by applying a sufficiently large nonlinear perturbation. This can be achieved through a detailed analysis of possible nonoscillatory solutions of the perturbed differential equation which may exist when the perturbation is sufficiently small. As a consequence the class of oscillation-generating perturbations is determined precisely with respect to the original nonoscillatory linear equation

Meridional circulation of gas into gaps opened by giant planets in three-dimensional low-viscosity disks

We examine the gas circulation near a gap opened by a giant planet in a protoplanetary disk. We show with high resolution 3D simulations that the gas flows into the gap at high altitude over the mid-plane, at a rate dependent on viscosity. We explain this observation with a simple conceptual model. From this model we derive an estimate of the amount of gas flowing into a gap opened by a planet with Hill radius comparable to the scale-height of a layered disk (i. e. a disk with viscous upper layer and inviscid midplane). Our estimate agrees with modern MRI simulations(Gressel et al., 2013). We conclude that gap opening in a layered disk can not slow down significantly the runaway gas accretion of Saturn to Jupiter-mass planets.Comment: in press as a Note in Icaru

Nuclear pasta structures and the charge screening effect

Non uniform structures of the nucleon matter at subnuclear densities are numerically studied by means of the density functional theory with relativistic mean-fields coupled with the electric field. A particular role of the charge screening effects is demonstrated.Comment: 11 pages, 9 figures, submitted to PR

Doing Deals in Japan: An Analysis of Recent Trends & Developments for the U.S. Practitioner

This article examines the process which is currently being played out in Japan by: (i) analyzing the recent changes in Japanese law of relevance to M&A deals, (ii) discussing some recent contested deals in Japan that may shed some light on current market practices, and (iii) providing an overview of the key issues that a U.S. practitioner will likely face when working on a Japanese deal…A good starting point in better understanding the remarkable changes in the Japanese M&A markets is to review the recent amendments to Japanese law, certain policy initiatives by the functional regulators, and other guidelines issued by Japanese government agencies… In concert with the changes in Japanese law, we have seen an increase in the number of contested deals in Japan in recent years…[T]he challenge for the U.S. practitioner is to boil down the complexity of Japanese M&A to a list of key issues that should be reviewed in any transaction which involves Japanese entities…[W]e have set forth some of the main issues under Japanese law and U.S. securities laws that have often come into play in Japanese deals…The current Japanese M&A market presents opportunities for U.S. companies and their advisors that are arguably the most promising in recent history…[G]iven the challenges posed by the opportunities in the Japanese M&A market, the importance of well informed and considered decision-making will be essential in order to ensure that U.S. companies compete and succeed in doing Japanese deals

Ultra-low-frequency self-oscillation of photocurrent in InxGa1–xAs/Al0.15Ga0.85As multiple-quantum-well p–i–n diodes

We report an observation of ultra-low-frequency self-oscillation of photocurrent in InxGa1–xAs/Al0.15Ga0.85As multiple-quantum-well p–i–n diodes. The photocurrent intensity shows self-oscillations with a characteristic frequency of ~0.1 Hz at low temperatures under reverse bias voltages. The photocurrent self-oscillation depends on applied bias voltage, temperature, illumination power, and indium content of quantum-well layers. These dependences indicate that the photocurrent self-oscillation is attributed to photogenerated carriers trapped in localized centers within InxGa1–xAs quantum-well regions

Finite size effects on kaonic pasta structures

Non-uniform structures of mixed phases at the first-order phase transition to charged kaon condensation are studied using a density functional theory within the relativistic mean field model. Including electric field effects and applying the Gibbs conditions in a proper way, we numerically determine density profiles of nucleons, electrons and condensed kaons. Importance of charge screening effects is elucidated and thereby we show that the Maxwell construction is effectively justified. Surface effect is also studied to figure out its effect on the density profiles