Mass Spectrum Dependence of Higgs-mediated mu-e Transition in the MSSM

In this paper, we study non-decoupling $\mu$ - $e$ transition effects by Higgs-mediated contribution in the MSSM, when some SUSY mass parameters are much greater than TeV. In order to treat CP-odd Higgs mass $m_{A^{0}}$ as a free parameter, we consider the non-universal Higgs mass model (NUHM), and assume the only left- or right-handed sleptons had flavor-mixing mass terms. If both Higgs-mediated and ordinary SUSY contribution are significant, the ratio of branching ratios \BR(\meg) / \BR(\maleal) becomes sensitive to SUSY mass parameters. We investigated these mass-sensitive regions and the behavior of the ratio \BR(\meg) / \BR(\maleal) in some mass spectrum of the NUHM, and found that this ratio drastically depends on the mass spectrum structure and chirality of flavor violation. Log factor from two split mass scale influences the way of interference between gaugino- and Higgs-mediated contributions significantly.Comment: 19 pages, 8 figures, it will appear in PR

Oscillatory convective modes in red giants: a possible explanation of the long secondary periods

We discuss properties of oscillatory convective modes in low-mass red giants, and compare them with observed properties of the long secondary periods (LSPs) of semi-regular red giant variables. Oscillatory convective modes are very nonadiabatic g$^{-}$ modes and they are present in luminous stars, such as red giants with \log L/{\rm L}_\odot \ga 3. Finite amplitudes for these modes are confined to the outermost nonadiabatic layers, where the radiative energy flux is more important than the convective energy flux. The periods of oscillatory convection modes increase with luminosity, and the growth times are comparable to the oscillation periods. The LSPs of red giants in the Large Magellanic Cloud (LMC) are observed to lie on a distinct period-luminosity sequence called sequence D. This sequence D period-luminosity relation is roughly consistent with the predictions for dipole oscillatory convective modes in AGB models if we adopt a mixing length of 1.2 pressure scale height ($\alpha = 1.2$). However, the effective temperature of the red-giant sequence of the LMC is consistent to models with $\alpha=1.9$, which predict periods too short by a factor of two.Comment: 7 pages, 6 figures, accepted for publication in MNRA

Classical Nonrelativistic Effective Field Theory and the Role of Gravitational Interactions

Coherent oscillation of axions or axion-like particles may give rise to long-lived clumps, called axion stars, because of the attractive gravitational force or its self-interaction. Such a kind of configuration has been extensively studied in the context of oscillons without the effect of gravity, and its stability can be understood by an approximate conservation of particle number in a non-relativistic effective field theory (EFT). We extend this analysis to the case with gravity to discuss the longevity of axion stars and clarify the EFT expansion scheme in terms of gradient energy and Newton's constant. Our EFT is useful to calculate the axion star configuration and its classical lifetime without any ad hoc assumption. In addition, we derive a simple stability condition against small perturbations. Finally, we discuss the consistency of other non-relativistic effective field theories proposed in the literature.Comment: 37 pages, 3 figure

Field electron emission of double walled carbon nanotube film prepared by drop casting method

Thick films of double walled carbon nanotubes (DWCN) were deposited on indium-tin-oxide (ITO) coated glass substrates by drop casting method and were studied for their field electron emission property in a parallel plate configuration using bare ITO coated glass as counter electrode. They show excellent field electron emission property with low turn-on-field of about 0.8 V/lm and threshold field of about 1.8 V/lm. Field enhancement factor calculated from the non-saturated region of the FN plot is about 1715. Field electron emission current was observed to be stable up to 3000 min, indicating thereby that DWCNs are excellent electron emitters with appreciable stable performance

Experimental Test of a New Equality: Measuring Heat Dissipation in an Optically Driven Colloidal System

Measurement of energy dissipation in small nonequilibrium systems is generally a difficult task. Recently, Harada and Sasa [Phys.Rev.Lett. 95, 130602(2005)] derived an equality relating the energy dissipation rate to experimentally accessible quantities in nonequilibrium steady states described by the Langevin equation. Here, we show the first experimental test of this new relation in an optically driven colloidal system. We find that this equality is validated to a fairly good extent, thus the irreversible work of a small system is estimated from readily obtainable quantities.Comment: 4 pages, 6 figure