Comments on the Evolution of Strongly Degenerate Neutrinos in the Early Universe

We reconsider the evolution of strongly degenerate neutrinos in the early universe. Our chief concern is the validity of the entropy conservation after the neutrino annihilation process has frozen out (so that the establishment of chemical equilibrium is not trivial). We argue that the entropy indeed conserves because elastic scattering keeps the neutrino and antineutrino distribution functions in the equilibrium form and the sum of their chemical potential keeps zero even after the neutrino annihilation freeze-out. We also simulate the evolution of the degenerate neutrino spectrum to support the argument. We conclude that the change in the neutrino degeneracy parameter when the relativistic degrees of freedom in the universe decreases is calculated using the entropy conservation and the lepton number conservation without worrying about at what temperature the neutrino annihilation process freezes out.Comment: 12 pages, 3 figure

Wino Dark Matter and Future dSph Observations

We discuss the indirect detection of the wino dark matter utilizing gamma-ray observations of dwarf spheroidal galaxies (dSphs). After carefully reviewing current limits with particular attention to astrophysical uncertainties, we show prospects of the wino mass limit in future gamma-ray observation by the Fermi-LAT and the GAMMA-400 telescopes. We find that the improvement of the so-called $J$-factor of both the classical and the ultra-faint dSphs will play a crucial role to cover whole mass range of the wino dark matter. For example, with $\delta (\log_{10}J) = 0.1$ for both the classical and the ultra-faint dSphs, whole wino dark matter mass range can be covered by 15 years and 10 years data at the Fermi-LAT and GAMMA-400 telescopes, respectively.Comment: 32 pages, 13 figure

High-Scale SUSY Breaking Models in light of the BICEP2 Result

The large value of the tensor-to-scalar ratio in the cosmic microwave background radiation reported by the BICEP2 collaboration gives strong impact on models of supersymmetry (SUSY). The large ratio indicates inflation with a high-energy scale and thus a high reheating temperature in general, and various SUSY models suffer from the serious gravitino and Polonyi problems. In this article, we discuss a class of the high-scale SUSY breaking models which are completely free from those problems. With especially focusing on the dark matter relic abundance, we examine how the BICEP2 result narrows down the parameter space of the models, assuming the simplest chaotic inflation model. We find that the mass of the dark matter is predicted to be less than about 1 TeV thanks to the non-thermal production in the early universe through the decay of abundant gravitinos produced after the reheating process. We also discuss implications in some details to dark matter searches at collider and indirect dark matter detection experiments.Comment: 17 pages, 6 figure

Lubrication effects on droplet manipulation by electrowetting-on-dielectric (EWOD)

Electrowetting has a potential to realize stand-alone point-of-care (POC) devices. Here we report droplet-migration characteristics on oil-infused electrowetting-on-dielectric (EWOD) substrates. We prepare sparse micropillars to retain the oil layer in order to exploit the layer as a lubricating film. A physical model of the droplet velocity is developed, and effects of the lubrication, the oil viscosity, the droplet volume, and the thickness of solid and liquid dielectric layers are discussed. It is found that the droplet velocity is scaled as square of E, which differs from a relationship of cube of E for droplets sliding down on liquid-infused surfaces by gravity. Furthermore, our device achieves droplet velocity of 1 mm/s at the applied voltage of 15 V. The velocity is approximately tenfold as high as the same condition (applied voltage and oil viscosity) on porous-structure-based liquid-infused surfaces. The achieved high velocity is explained by a lubrication-flow effect.Comment: 16 pages, 10 figure

An Optimum Choice of Strategic Marketing for Indonesian Plywood Industry: Operationalization of Porter Five Forces Model using Analytic Hierarchy Process

The purpose of this study is to present an application of Analytic Hierarchy Process (AHP) for determining the best marketing strategy of Indonesian plywood industry. This paper applies Michael Porter???s industry analysis techniques to identify the existing competitive advantages as well as the key factors of business success and to create the strategy framework of the positioning for plywood industry. This approach is based on generic strategies as criteria for selecting competitive market strategy. The integration of Analytic Hierarchy Process and five forces can set up a series of procedure to evaluate the current strategy by chosen the important criteria. The major advantage of applying this framework is that the company will systematically select an optimum choice of competitive market strategy with planning decision and implementation to realize the achievement of competitive advantage in plywood industry