Schroedinger functional formalism with domain-wall fermion

Finite volume renormalization scheme is one of the most fascinating scheme for non-perturbative renormalization on lattice. By using the step scaling function one can follow running of renormalized quantities with reasonable cost. It has been established the Schroedinger functional is very convenient to define a field theory in a finite volume for the renormalization scheme. The Schroedinger functional, which is characterized by a Dirichlet boundary condition in temporal direction, is well defined and works well for the Yang-Mills theory and QCD with the Wilson fermion. However one easily runs into difficulties if one sets the same sort of the Dirichlet boundary condition for the overlap Dirac operator or the domain-wall fermion. In this paper we propose an orbifolding projection procedure to impose the Schroedinger functional Dirichlet boundary condition on the domain-wall fermion.Comment: 32 page

Orbital Decay and Tidal Disruption of a Star Cluster: Analytical Calculation

The orbital decay and tidal disruption of a star cluster in a galaxy is studied in an analytical manner. Owing to dynamical friction, the star cluster spirals in toward the center of the galaxy. Simultaneously, the galactic tidal field strips stars from the outskirts of the star cluster. Under an assumption that the star cluster undergoes a self-similar evolution, we obtain the condition and timescale for the star cluster to reach the galaxy center before its disruption. The result is used to discuss the fate of so-called intermediate-mass black holes with >10^3 M(sun) found recently in young star clusters of starburst galaxies and also the mass function of globular clusters in galaxies.Comment: 12 pages, 1 PS file for 2 figures, to appear in The Astrophysical Journa

A Geometrical Relationship between Broad-Line Clouds and an Accretion Disk around Active Galactic Nuclei

Recent hard X-ray spectroscopy of active galactic nuclei has strongly suggested that double-peaked, very broad Fe K emission arises from an accretion disk around the central engine. Model fitting of the observed Fe K emission line profile makes it possible to estimate a probable inclination angle of the accretion disk. In order to study the geometrical relationship between the accretion disk and broad emission-line regions (BLRs), we investigate the correlation between the inclination angle of the accretion disk and the velocity width of BLRs for 18 type-1 Seyfert galaxies. We found that there may be a negative correlation between them, i.e., Seyfert nuclei with a more face-on accretion disk tend to have larger BLR velocity widths, suggesting that the BLRs are not coplanar with respect to the accretion disk. The most probable interpretation may be that the BLRs arise from outer parts ({\it r} $\sim$ 0.01 pc) of a warped accretion disk illuminated by the central engine.Comment: 11 pages, 3 figures; accepted for Publications of the Astronomical Society of Japa

Runaway Merging of Black Holes: Analytical Constraint on the Timescale

Following the discovery of a black hole (BH) with a mass of 10^3-10^6 M(sun) in a starburst galaxy M82, we study formation of such a BH via successive merging of stellar-mass BHs within a star cluster. The merging has a runaway characteristic. This is because massive BHs sink into the cluster core and have a high number density, and because the merging probability is higher for more massive BHs. We use the Smoluchowski equation to study analytically the evolution of the BH mass distribution. Under favorable conditions, which are expected for some star clusters in starburst galaxies, the timescale of the runaway merging is at most of order 10^7 yr. This is short enough to account for the presence of a BH heavier than 10^3 M(sun) in an ongoing starburst region.Comment: 10 pages, no figures, to appear in The Astrophysical Journal (Letters

INCOME ELASTICITY OF RICE DEMAND IN JAPAN AND ITS IMPLICATIONS: CROSS-SECTIONAL DATA ANALYSIS

Researchers believe that rice in developed countries such as Japan became an inferior good a few decades ago. This study employs the flexible complete demand system for the recent cross-sectional data in Japan. Our results clearly show that rice in Japan is a normal good contrary to the preceding studies. The objective of this research is to analyze the food consumption patterns and to conduct econometric analysis of food demand structure. We use the monthly basis cross-sectional household data, Annual Report on the Family Income and Expenditure Survey (FIES) in 1997. Food items are non-glutinous rice, bread, noodle, fresh fish, and shellfish, fresh meat, milk, eggs, fresh vegetables, fresh fruits, fats and oil, and food away from home. We apply various single equation models: Working-Leser model is estimated by OLS, Heckman's two-step estimator, and Tobit estimator. All coefficients have correct signs and are statistically significant. For the complete demand system analysis, we apply the almost ideal demand (AIDS) system. To correct a censored dependent variable problem, we additionally utilize a censored regression approach. Results from AIDS models show that the expenditure elasticity of rice is positive and close to one. Marshallian and Hicksian own-price elasticities for rice are highly elastic for all models. Fresh meats and rice are mild complements in all models; however, fresh fish and rice show the mixed results.AIDS model, Cross-section, Income Elasticity, Japan, Rice Consumption, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,

Dynamical Gauge Boson and Strong-Weak Reciprocity

It is proposed that asymptotically nonfree gauge theories are consistently interpreted as theories of composite gauge bosons. It is argued that when hidden local symmetry is introduced, masslessness and coupling universality of dynamically generated gauge boson are ensured. To illustrate these ideas we take a four dimensional Grassmannian sigma model as an example and show that the model should be regarded as a cut-off theory and there is a critical coupling at which the hidden local symmetry is restored. Propagator and vertex functions of the gauge field are calculated explicitly and existence of the massless pole is shown. The beta function determined from the $Z$ factor of the dynamically generated gauge boson coincides with that of an asymptotic nonfree elementary gauge theory. Using these theoretical machinery we construct a model in which asymptotic free and nonfree gauge bosons coexist and their running couplings are related by the reciprocally proportional relation.Comment: 19 pages, latex, 6 eps figures, a numbers of corrections are made in the tex