We discuss the conditions for a non-vanishing Dirac phase δ and mixing angle θ 13 , sources of CP violation in neutrino oscillations, to be uniquely responsible for the observed matter-antimatter asymmetry of the Universe through leptogenesis. We show that this scenario, that we call δ-leptogenesis, is viable when the degenerate limit for the heavy right-handed (RH) neutrino spectrum is considered. We derive an interesting joint condition on sin θ 13 and the absolute neutrino mass scale that can be tested in future neutrino oscillation experiments. In the limit of the hierarchical heavy RH neutrino spectrum, we strengthen the previous result that δ-leptogenesis is only very marginally allowed, even when the production from the two heavier RH neutrinos is taken into account. An improved experimental upper bound on sin θ 13 and/or an account of quantum kinetic effects could completely rule out this option in the future. Therefore, δ-leptogenesis can be also regarded as motivation for models with degenerate heavy neutrino spectrum. Viability of Dirac phase leptogenesisJournal of Cosmology and Astroparticle Physics 04 (2008) 033 (stacks.iop.org/JCAP/2008/i=04/a=033) 3 More exactly, in [7], 4 × 10 8 GeV was found. Here we are using a slightly higher value that is obtained, as we will see, when the reduced experimental error on the baryon asymmetry and on the atmospheric neutrino mass scale is taken into account. 4 Flavor effects were first considered in [12] and then in [13] in the particular case of two RH neutrinos. However, in these papers, it was found that flavor effects can change the final asymmetry only of O(1) factors compared to the unflavored case. The possibility for a large enhancement was first found in [14] in the case of resonant leptogenesis and more generally in [15]-[17]. Here, in particular, there was also first discussed the potential role of low-energy phases in providing an additional CP violating contribution to the flavored CP asymmetries.Journal of Cosmology and Astroparticle Physics 04 (2008) 033 (stacks.iop.org/JCAP/2008/i=04/a=033)

A realistic model to study the properties of an aqueous electrolyte surface has been developed. The complex liquid surface consisting of a large number of interacting particles, ions and dipoles, is modelled using a Monte Carlo technique considering grand canonical sampling. The possible interactions existing in the system are charge-charge, charge-dipole, chargequadrupole and dipole-dipole. The concentration dependence of the diffusion coefficient suggests a first order phase transition (structural transition), while its temperature dependence indicates the existence of a second order phase transition. A critical analysis of the effect of decreasing temperature on the samples with added cations to limit motion of the particles in the surface reveals an interesting feature-a signature of glass transition.

We investigated the signal characteristics of a 46 mm small optical disk in a blue laser system [laser wavelength, 405 nm; numerical aperture (NA), 0.85]. To determine the physical dimensions of the rim area of the disk, we considered some factors affecting this rim area. We confirmed the transcription of the substrate, and the thickness of the cover layer of the disc. Also, by spin coating and selecting the optimum viscosity of the resin used for the 0.1-mm-thick cover layer, it was possible to reduce rim area from 1.5 mm to 1.0 mm. Also, we confirmed that the thickness of the substrate for sufficient mobility should be thicker than 0.5 mm.

We report the random pattern signal characteristics of the super resolution near field structure (Super-RENS) disk in a red laser optical system. (Laser wavelength 659 nm, numerical aperture 0.6) We improved the carrier to noise ratio (CNR) characteristics and the low frequency noise by optimizing the layer design and the pit structure, which results in 53 dB CNR at 173 nm pit length. It is equivalent to 50 GB capacity if it is converted by Blu-ray Disc (BD) specification according to the ratio of beam size. We also improved the readout power margin and the stability greatly by introducing the thermal control layer. The eye pattern under phase locked loop (PLL) state could be obtained through equalization adjustment (EQ). Through above improvements, we obtain the bER of 4.6×10-4 at 50 GB level by using partial response maximum likelihood (PRML) method.

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