Results for "Toshinori Matsui"

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Higgs inflation scenario in a radiative seesaw model and its testability at the ILCMay 22 2014The Higgs inflation scenario is an approach to realize the cosmic inflation, where the Higgs boson plays a role of the inflaton. In the minimal model, it would be difficult to satisfy theoretical constraints from vacuum stability and perturbative unitarity. ... More
Gravitational waves as a probe of extended scalar sectors with the first order electroweak phase transitionSep 28 2015Dec 13 2015We discuss spectra of gravitational waves which are originated by the strongly first order phase transition at the electroweak symmetry breaking, which is required for a successful scenario of electroweak baryogenesis. Such spectra are numerically evaluated ... More
Loop Suppression of Dirac Neutrino Mass in the Neutrinophilic Two Higgs Doublet ModelMay 20 2013Nov 10 2013We extend the scalar sector of the neutrinophilic two Higgs doublet model, where small masses of Dirac neutrinos are obtained via a small vacuum expectation value v_nu of the neutrinophilic SU(2)_L-doublet scalar field which has a Yukawa interaction with ... More
Neutrino Mass and Dark Matter from Gauged B$-$L BreakingMay 29 2015We discuss a new radiative seesaw model with the gauged B$-$L symmetry which is spontaneously broken. We improve the previous model by using the anomaly-free condition without introducing too many fermions. In our model, dark matter, tiny neutrino masses ... More
Testability of the Higgs inflation scenario in a radiative seesaw modelMay 01 2013The Higgs inflation scenario is an approach to realize the inflation, in which the Higgs boson plays a role of the inflaton without introducing a new particle. We investigate a Higgs inflation scenario in the so-called radiative seesaw model proposed ... More
Synergy between measurements of the gravitational wave and the triple Higgs coupling in probing first order phase transitionApr 07 2016Jul 20 2016Probing the Higgs potential and new physics behind the electroweak symmetry breaking is one of the most important issues of particle physics. In particular, nature of electroweak phase transition is essential for understanding physics at the early Universe, ... More
Gravitational waves from first order electroweak phase transition in models with the $U(1)_X^{}$ gauge symmetryFeb 08 2018We consider a standard model extension equipped with a dark sector where the $U(1)_X^{}$ Abelian gauge symmetry is spontaneously broken by the dark Higgs mechanism. In this framework, we investigate patterns of the electroweak phase transition as well ... More
Higgs inflation in a radiative seesaw modelNov 19 2012Apr 13 2013We investigate a simple model to explain inflation, neutrino masses and dark matter simultaneously. This is based on the so-called radiative seesaw model proposed by Ma in order to explain neutrino masses and dark matter by introducing a $Z_2$-odd isospin ... More
Neutrino Mass and Dark Matter from Gauged $U(1)_{B-L}$ BreakingMay 08 2014Jul 09 2014We propose a new model where the Dirac mass term for neutrinos, the Majorana mass term for right-handed neutrinos, and the other new fermion masses arise via the spontaneous breakdown of the $U(1)_{B-L}$ gauge symmetry. The anomaly-free condition gives ... More
Algorithms for integrals of holonomic functions over domains defined by polynomial inequalitiesAug 24 2011Oct 29 2011We present an algorithm for computing a holonomic system for a definite integral of a holonomic function over a domain defined by polynomial inequalities. If the integrand satisfies a holonomic difference-differential system including parameters, then ... More
Final Results of the MEG ExperimentJun 27 2016Transitions of charged leptons from one generation to another are basically prohibited in the Standard Model because of the mysteriously tiny neutrino masses, although such flavor-violating transitions have been long observed for quarks and neutrinos. ... More
Length and multiplicity of the local cohomology with support in a hyperplane arrangementSep 06 2015Let $R$ be the polynomial ring in $n$ variables with coefficients in a field $K$ of characteristic zero. Let $D_n$ be the $n$-th Weyl algebra over $K$. Suppose that $f \in R$ defines a hyperplane arrangement in the affine space $K^n$. Then the length ... More
Localization, local cohomology, and the b-function of a D-module with respect to a polynomialSep 15 2016Given a $D$-module $M$ generated by a single element, and a polynomial $f$, one can construct several $D$-modules attached to $M$ and $f$ and can define the notion of the (generalized) $b$-function following M. Kashiwara. These modules are closely related ... More
Operational calculus for holonomic distributions in the framework of D-module theoryApr 02 2016Let $f$ be a real polynomial of $x = (x_1,\dots,x_n)$ and $\varphi$ be a locally integrable function of $x$ which satisfies a holonomic system of linear differential equations. We study the distribution $f_+^\lambda\varphi$ with a meromorphic parameter ... More
Annihilators of Laurent coefficients of the complex power for normal crossing singularitySep 05 2015Let $f$ be a real-valued real analytic function defined on an open set of $\mathbb{R}^n$. Then the complex power $f_+^\lambda$ is defined as a distribution with a holomorphic parameter $\lambda$. We determine the annihilator (in the ring of differential ... More
Syzygies of Cohen-Macaulay modules and Grothendieck groupsJul 21 2016We study the converse of a theorem of Butler and Auslander-Reiten. We show that a Cohen-Macaulay local ring with an isolated singularity has only finitely many isomorphism classes of indecomposable summands of syzygies of Cohen-Macaulay modules if the ... More
Lepton Flavor Violating Decays - Review & OutlookMay 30 2006May 31 2006Here I review the status and prospects of experimental investigations into lepton flavor violation (LFV) in charged leptons. Rare LFV processes are naturally expected to occur through loops of TeV scale particles predicted by supersymmetric theories or ... More
An algorithm to compute the differential equations for the logarithm of a polynomialJan 16 2012We present an algorithm to compute the annihilator of (i.e., the linear differential equations for) the logarithm of a polynomial in the ring of differential operators with polynomial coefficients. The algorithm consists of differentiation with respect ... More
Gravitational waves and Higgs boson couplings for exploring first order phase transition in the model with a singlet scalar fieldSep 01 2016We calculate the spectrum of gravitational waves originated from strongly first order electroweak phase transition in the extended Higgs model with a real singlet field. In order to calculate the bubble nucleation rate, we perform a two-field analysis ... More
Indirect reach of heavy MSSM Higgs bosons by precision measurements at future lepton collidersMay 14 2015Sep 11 2015In the Minimal Supersymmetric Standard Model (MSSM), the bottom Yukawa coupling of the Higgs boson can considerably deviate from its Standard Model prediction due to non-decoupling effects. We point out that the ratio of the Higgs boson decay branching ... More
Algorithm for computing local Bernstein-Sato idealsJun 30 2008Given $p$ polynomials of $n$ variables over a field $k$ of characteristic 0 and a point $a \in k^n$, we propose an algorithm computing the local Bernstein-Sato ideal at $a$. Moreover with the same algorithm we compute a constructible stratification of ... More
Algorithms for D-modules --- restriction, tensor product, localization, and local cohomology groupsMay 02 1998We describe algorithms for computing various functors for algebraic D-modules, i.e. systems of linear partial differential equations with polynomial coefficients. We will give algorithms for restriction, tensor product, localization, and local cohomology ... More
Boundary bound states in the SUSY sine-Gordon model with Dirichlet boundary conditionsMay 04 2012We analyze the ground state structure of the supersymmetric sine-Gordon model via the lattice regularization. The nonlinear integral equations are derived for any values of the boundary parameters by the analytic continuation and showed three different ... More
The structure of preenvelopes with respect to maximal Cohen-Macaulay modulesApr 30 2015This paper studies the structure of special preenvelopes and envelopes with respect to maximal Cohen-Macaulay modules. We investigate the structure of them in terms of their kernels and cokernels. Moreover, using this result, we also study the structure ... More
An algorithm for de Rham cohomology groups of the complement of an affine variety via D-module computationJan 26 1998We give an algorithm to compute the following cohomology groups on $U = \C^n \setminus V(f)$ for any non-zero polynomial $f \in \Q[x_1, ..., x_n]$; 1. $H^k(U, \C_U)$, $\C_U$ is the constant sheaf on $U$ with stalk $\C$. 2. $H^k(U, \Vsc)$, $\Vsc$ is a ... More
Spinon excitations in the spin-1 XXZ chain and hidden supersymmetryJul 14 2016Sep 20 2016We study spinon excitations of the integrable spin-1 (Fateev-Zamolodchikov; FZ) chain and their relation to the hidden supersymmetry. Using the notion of the supercharges earlier introduced to the spin chains, which change the system length by one, we ... More
Dynamical supersymmetry on the XXX spin chainApr 22 2015Apr 30 2015We show the XXX model has the N = 2 dynamical supersymmetry. Using the supercharges defined by the Jordan-Wigner fermions, it was found that the anti-commutation relation of the supercharges gives the Hamiltonian of the XXX model with magnetic field. ... More
Multi-state asymmetric simple exclusion processesNov 29 2013Dec 08 2014It is known that the Markov matrix of the asymmetric simple exclusion process (ASEP) is invariant under the Uq(sl2) algebra. This is the result of the fact that the Markov matrix of the ASEP coincides with the generator of the Temperley-Lieb (TL) algebra, ... More
A characterization of ARMA and Fractional ARIMA models with infinitely divisible innovationsMar 25 2007Apr 27 2015The object of this paper is to study the asymptotic dependence structure of the linear time series models with infinitely divisible innovations by the use of their characteristic functions. Autoregressive moving-average (ARMA) models and fractional autoregressive ... More
Log-convexity and the cycle index polynomials with relation to compound Poisson distributionsSep 22 2016We extend the exponential formula by Bender and Canfield (1996), which relates log-concavity and the cycle index polynomials. The extension clarifies the log-convexity relation. The proof is by noticing the property of a compound Poisson distribution ... More
Classifying dense (co)resolving subcategories of exact categories via Grothendieck groupsAug 02 2016Nov 06 2016Classification problems of subcategories have been deeply considered so far. In this paper, we discuss classifying dense (co)resolving subcategories of exact categories via their Grothendieck groups. This study is motivated by the classification of dense ... More
Boundary effects on the supersymmetric sine-Gordon model through light-cone lattice approachApr 15 2014Jun 19 2014We discussed subspaces of the N=1 supersymmetric sine-Gordon model with Dirichlet boundaries through light-cone lattice regularization. In this paper, we showed, unlike the periodic boundary case, both of Neveu-Schwarz (NS) and Ramond (R) sectors of a ... More
Boundary effects on the lattice/continuum correspondence: the spin-1/2 XXZ chain and the sine-Gordon modelDec 08 2014We derived the corresponding boundary condition on Fermi fields to the spin-1/2 Heisenberg chain with boundary magnetic fields. In order to obtain the correct boundary condition from the variation of the action at the edges, we carefully treat the oscillating ... More
Prediction of components in random sumsApr 27 2015Jul 10 2015We consider predictions of the random number and the magnitude of each iid component in a random sum based on its distributional structure, where only a total value of the sum is available and where iid random components are non-negative. The problem ... More
Model selection criteria for nonlinear mixed effects modelingFeb 24 2014We consider constructing model selection criteria for evaluating nonlinear mixed effects models via basis expansions. Mean functions and random functions in the mixed effects model are expressed by basis expansions, then they are estimated by the maximum ... More
Classifying dense (co)resolving subcategories of exact categories via Grothendieck groupsAug 02 2016Classification problems of subcategories have been deeply considered so far. In this paper, we discuss classifying dense (co)resolving subcategories of exact categories via their Grothendieck groups. This study is motivated by the classification of dense ... More
Prediction in a non-homogeneous Poisson cluster modelJul 19 2013Nov 28 2013A non-homogeneous Poisson cluster model is studied, motivated by insurance applications. The Poisson center process which expresses arrival times of claims, triggers off cluster member processes which correspond to number or amount of payments. The cluster ... More
Fisher Information Matrix of General Stable Distributions Close to the Normal DistributionFeb 26 2005We investigate behavior of the Fisher information matrix of general stable distributions. DuMouchel (1975, 1983) proved that the Fisher information of characteristic exponent \alpha diverges to infinity as \alpha approaches 2. Nagaev and Shkol'nik (1988) ... More
Decoding a Class of Affine Variety Codes with Fast DFTSep 29 2012An efficient procedure for error-value calculations based on fast discrete Fourier transforms (DFT) in conjunction with Berlekamp-Massey-Sakata algorithm for a class of affine variety codes is proposed. Our procedure is achieved by multidimensional DFT ... More
On Spectral Gap,U(1) Symmetry and Split Property in Quantum Spin ChainsAug 11 2008We consider a class of ground states for quantum spin chains on an integer lattice. First we show that presence of the spectral gap between the ground state energy and the rest of spectrum implies the split property of certain subsystems.As a corollary, ... More
Gauge Symmetry and Neural NetworksDec 26 2001We propose a new model of neural network. It consists of spin variables to describe the state of neurons as in the Hopfield model and new gauge variables to describe the state of synapses. The model possesses local gauge symmetry and resembles lattice ... More
BEC of Free Bosons on NetworksSep 02 2005We consider free Bosons hopping on a network(infinite graph). The condition for Bose-Einstein condensation is given in terms of the random walk on a graph. In case of periodic lattices, we also consider Boson moving in an external periodic potential and ... More
A Note on Bulk Quantum Turing MachineNov 12 2004Nov 13 2004Recently, among experiments for realization of quantum computers, NMR quantum computers have achieved the most impressive succession. There is a model of the NMR quantum computation,namely Atsumi and Nishino's bulk quantum Turing Machine. It assumes, ... More
On the evaluation of form factors and correlation functions for the integrable spin-s XXZ chains via the fusion methodMar 22 2011Revising the derivation of the previous papers, for the integrable spin-$s$ XXZ chain we express any form factor in terms of a single sum over scalar products of the spin-1/2 XXZ chain. With the revised method we express the spin-$s$ XXZ correlation function ... More
Correlation functions of the integrable higher-spin XXX and XXZ spin chains through the fusion methodJul 03 2009Nov 19 2009For the integrable higher-spin XXX and XXZ spin chains we present multiple-integral representations for the correlation function of an arbitrary product of Hermitian elementary matrices in the massless ground state. We give a formula expressing it by ... More
Phase coexistence phenomena in an extreme case of the misanthrope process with open boundariesMay 03 2016Jul 27 2016The misanthrope process is a class of stochastic interacting particle systems, generalizing the simple exclusion process. It allows each site of the lattice to accommodate more than one particle. We consider a special case of the one dimensional misanthrope ... More
The Ξ_Q - Ξ_Q' Mixing and Heavy Baryon MassesMay 13 1996Sep 26 1996We examine the $\Xi_Q - \Xi'_Q$ mixing and heavy baryon masses in the heavy quark effective theory with the $\mq$ corrections. In the conventional baryon assignment, we obtain the mixing angle $\cos^2 \theta = 0.87\pm 0.03$ in virtue of the Gell-Mann-Okubo ... More
A geometric degree formula for $A$-discriminants and Euler obstructions of toric varietiesJul 20 2008Dec 14 2008We give explicit formulas for the dimensions and the degrees of $A$-discriminant varieties introduced by Gelfand-Kapranov-Zelevinsky. Our formulas can be applied also to the case where the $A$-discriminant varieties are higher-codimensional and their ... More
The extremogram and the cross-extremogram for a bivariate GARCH(1,1) processMay 20 2015In this paper, we derive some asymptotic theory for the extremogram and cross-extremogram of a bivariate GARCH(1,1) process. We show that the tails of the components of a bivariate GARCH(1,1) process may exhibit power law behavior but, depending on the ... More
Integral representations of one dimensional projections for multivariate stable densitiesAug 23 2006We consider the numerical evaluation of one dimensional projections of general multivariate stable densities introduced by Abdul-Hamid and Nolan (1998). In their approach higher order derivatives of one dimensional densities are used, which seem to be ... More
Gravitational relaxation of electroweak hierarchy problemAug 31 2016The current status of the LHC experiments has aggravated the electroweak hierarchy problem as severe as the cosmological constant problem. Therefore, recently, theoretically different approaches to the electroweak hierarchy problem have been explored. ... More
Microlocal study of Lefschetz fixed point formulas for higher-dimensional fixed point setsDec 24 2008We introduce new Lagrangian cycles which encode local contributions of Lefschetz numbers of constructible sheaves into geometric objects. We study their functorial properties and apply them to Lefschetz fixed point formulas with higher-dimensional fixed ... More
An Equivariant Liapunov Stability Test and the Energy-Momentum-Casimir MethodJul 12 2001Feb 11 2002We present an equivariant Liapunov stability criterion for dynamical systems with symmetry. This result yields a simple proof of the energy-momentum-Casimir stability analysis of relative equilibria of equivariant Hamiltonian systems.
Algebraic aspects of the correlation functions of the integrable higher-spin XXZ spin chains with arbitrary entriesMay 06 2010We discuss some fundamental properties of the XXZ spin chain, which are important in the algebraic Bethe-ansatz derivation for the multiple-integral representations of the spin-s XXZ correlation function with an arbitrary product of elementary matrices. ... More
Maximal Cohen-Macaulay approximations and Serre's conditionDec 27 2014This paper studies the relationship between Serre's condition $(\R_n)$ and Auslander--Buchweitz's maximal Cohen--Macaulay approximations. It is proved that a Gorenstein local ring satisfies $(\R_n)$ if and only if every maximal Cohen--Macaulay module ... More
Decoding of Projective Reed-Muller Codes by Dividing a Projective Space into Affine SpacesDec 14 2014Dec 08 2015A projective Reed-Muller (PRM) code, obtained by modifying a (classical) Reed-Muller code with respect to a projective space, is a doubly extended Reed-Solomon code when the dimension of the related projective space is equal to 1. The minimum distance ... More
Effects of Minor Mergers on Coalescence of a Supermassive Black Hole BinaryDec 24 2008Dec 25 2008We study the possibility that minor mergers resolve the loss cone depletion problem, which is the difficulty occured in the coalescence process of the supermassive black hole (SMBH) binary, by performing numerical simulations with a highly accurate $N$-body ... More
Higgs vacuum metastability in primordial inflation, preheating, and reheatingFeb 05 2016Mar 02 2016Current measurements of the Higgs boson mass and top Yukawa coupling suggest that the effective Higgs potential develops an instability below the Planck scale. If the energy scale of inflation is as high as the GUT scale, inflationary quantum fluctuations ... More
Form factors of integrable higher-spin XXZ chains and the affine quantum-group symmetryJul 11 2008Sep 04 2008We derive exactly scalar products and form factors for integrable higher-spin XXZ chains through the algebraic Bethe-ansatz method. Here spin values are arbitrary and different spins can be mixed. We show the affine quantum-group symmetry, $U_q(\hat{sl_2})$, ... More
Some improvements in numerical evaluation of symmetric stable density and its derivativesAug 24 2004Aug 25 2004We propose improvements in numerical evaluation of symmetric stable density and its partial derivatives with respect to the parameters. They are useful for more reliable evaluation of maximum likelihood estimator and its standard error. Numerical values ... More
Higgs vacuum metastability in primordial inflation, preheating, and reheatingFeb 05 2016Nov 16 2016Current measurements of the Higgs boson mass and top Yukawa coupling suggest that the effective Higgs potential develops an instability below the Planck scale. If the energy scale of inflation is as high as the GUT scale, inflationary quantum fluctuations ... More
Prethick subcateogries of modules and characterizations of local ringsDec 27 2014Jun 04 2015This paper studies characterizing local rings in terms of homological dimensions. The key tool is the notion of a prethick subcategory which we introduce in this paper. Our methods recover the theorems of Salarian, Sather-Wagstaff and Yassemi.
Singularity categories and singular equivalences for resolving subcategoriesDec 27 2014May 27 2016Let $\X$ be a resolving subcategory of an abelian category. In this paper we investigate the singularity category $\ds(\underline\X)=\db(\mod\underline\X)/\kb(\proj(\mod\underline\X))$ of the stable category $\underline\X$ of $\X$. We consider when the ... More
Molecular dynamics investigation of dislocation pinning by a nanovoid in copperDec 27 2004Jun 14 2005Interactions between an edge dislocation and a void in copper are investigated by means of molecular dynamics simulation. The depinning stresses of the leading partial and of the trailing partial show qualitatively different behaviors. The depinning stress ... More
Motivic Milnor fibers and Jordan normal forms of Milnor monodromiesFeb 23 2012By calculating the equivariant mixed Hodge numbers of motivic Milnor fibers introduced by Denef-Loeser, we obtain explicit formulas for the Jordan normal forms of Milnor monodromies. The numbers of the Jordan blocks will be described by the Newton polyhedron ... More
Double Counting in $2^t$-ary RSA Precomputation Reveals the Secret ExponentJul 28 2014A new fault attack, double counting attack (DCA), on the precomputation of $2^t$-ary modular exponentiation for a classical RSA digital signature (i.e., RSA without the Chinese remainder theorem) is proposed. The $2^t$-ary method is the most popular and ... More
The final SLD results for ALR and AleptonFeb 09 2001We present the final measurements of the left-right cross-section asymmetry (ALR) for Z boson production by e+e- collisions and Z boson-lepton coupling asymmetry parameters Ae, Amu, and Atau in leptonic Z decays with the SLD detector at the SLAC Linear ... More
Milnor fibers over singular toric varieties and nearby cycle sheavesSep 18 2008Dec 02 2008We propose a new sheaf-theoretical method for the calculation of the monodromy zeta functions of Milnor fibrations. As an application, classical formulas of Kushnirenko and Varchenko etc. concerning polynomials on $\CC^n$ will be generalized to polynomial ... More
Monodromy at infinity of polynomial maps and Newton polyhedra (with Appendix by C. Sabbah)Dec 28 2009Feb 22 2012By introducing motivic Milnor fibers at infinity of polynomial maps, we propose some methods for the study of nilpotent parts of monodromies at infinity. The numbers of Jordan blocks in the monodromy at infinity will be described by the Newton polyhedron ... More
On the sizes of the Jordan blocks of monodromies at infinityFeb 23 2012We obtain general upper bounds of the sizes and the numbers of Jordan blocks for the eigenvalues $\lambda \not= 1$ in the monodromies at infinity of polynomial maps.
Anomalous gauge theories revisitedDec 28 2004Feb 03 2005A possible formulation of chiral gauge theories with an anomalous fermion content is re-examined in light of the lattice framework based on the Ginsparg-Wilson relation. It is shown that the fermion sector of a wide class of anomalous non-abelian theories ... More
Generalized fractional Ornstein-Uhlenbeck processesJul 14 2008We introduce an extended version of the fractional Ornstein-Uhlenbeck (FOU) process where the integrand is replaced by the exponential of an independent L\'evy process. We call the process the generalized fractional Ornstein-Uhlenbeck (GFOU) process. ... More
Fractional absolute moments of heavy tailed distributionsJan 21 2013Jun 03 2014Several convenient methods for calculation of fractional absolute moments are given with application to heavy tailed distributions. We use techniques of fractional differentiation to obtain formulae for $E[|X-\mu|^\gamma]$ with $1<\gamma<2$ and $\mu\in\mathbb{R}$. ... More
Inverse-free Berlekamp-Massey-Sakata Algorithm and Small Decoders for Algebraic-Geometric CodesMay 02 2007This paper proposes a novel algorithm for finding error-locators of algebraic-geometric codes that can eliminate the division-calculations of finite fields from the Berlekamp-Massey-Sakata algorithm. This inverse-free algorithm provides full performance ... More
Thick tensor ideals of right bounded derived categoriesNov 09 2016Let R be a commutative noetherian ring. Denote by D^-(R) the derived category of cochain complexes X of finitely generated R-modules with H^i(X)=0 for i>>0. Then D^-(R) has the structure of a tensor triangulated category with tensor product \otimes_R^L ... More
On Quasifree Representations of Infinite Dimensional Symplectic GroupApr 18 2002We consider an infinite dimensional generalization of Metaplectic representations (Weil representations) for the (double covering of) symplectic group. Given quasifree states of an infinite dimensional CCR algebra, projective unitary representations of ... More
Quasi-excitations and superconductivity in the t-J model on a ladderOct 01 1997We study the t-J model on a ladder by using slave-fermion-CP^1 formalism which is quite useful for study of lightly-doped high-T_c cuprates. By integrating half of spin variables, we obtain a low-energy effective field theory whose spin part is nothing ... More
Quantized meson fields in and out of equilibrium. I : Kinetics of meson condensate and quasi-particle excitationsFeb 24 2008Jun 04 2008We formulate a kinetic theory of self-interacting meson fields with an aim to describe the freezeout stage of the space-time evolution of matter in ultrarelativistic nuclear collisions. Kinetic equations are obtained from the Heisenberg equation of motion ... More
Note on MacLennan-Zubarev Ensembles and QuasiStatic ProcessesMay 17 2006Relation between natural nonequilibrium steady states of Ruelle and MacLennan-Zubarev ensembles is discussed for a system consisting of $M$ infinitely extended systems coupled with a small system. And a characterization of quasistatic processes is investigated ... More
Monodromy zeta functions at infinity, Newton polyhedra and constructible sheavesSep 18 2008Dec 28 2009By using sheaf-theoretical methods such as constructible sheaves, we generalize the formula of Libgober-Sperber concerning the zeta functions of monodromy at infinity of polynomial maps into various directions. In particular, some formulas for the zeta ... More
A Disk Galaxy of Old Stars at z ~ 2.5Dec 19 2003We describe observations of a galaxy in the field of the $z=2.483$ radio galaxy 4C 23.56, photometrically selected to have a spectral-energy distribution consistent with an old stellar population at the redshift of the radio galaxy. Exploration of redshift--stellar-population-reddening ... More
Amino acid precursors from a simulated lower atmosphere of Titan: Experiments of cosmic ray energy source with 13 C- and 18 O-stable isotope probing mass spectrometrySep 24 2013Sep 25 2013The organic haze of aerosols that shrouds the Saturnian moon Titan has previously been studied by both observations and laboratory simulation experiments. Here we report the abiotic formation of amino acid precursors in complex organic molecules during ... More
Properties of powers of functions satisfying second-order linear differential equations with applications to statisticsMay 18 2014We derive properties of powers of a function satisfying a second-order linear differential equation. In particular we prove that the n-th power of the function satisfies an (n+1)-th order differential equation and give a simple method for obtaining the ... More
A Localization Algorithm for $D$-modulesNov 06 1998Jul 15 1999We present a method to compute the holonomic extension of a $D$-module from a Zariski open set in affine space to the whole space. A particular application is the localization of coherent $D$-modules which are holonomic on the complement of an affine ... More
Quantum liquid crystals of helium monolayersJun 17 2014Feb 05 2016The second-layer phase diagrams of $^4$He and $^3$He adsorbed on graphite are investigated. Intrinsically rounded specific-heat anomalies are observed at 1.4 K and 0.9 K, respectively, over extended density regions in between the liquid and incommensurate ... More
Possible quantum liquid crystal phases of helium monolayersJun 17 2014Nov 05 2016The second-layer phase diagrams of $^4$He and $^3$He adsorbed on graphite are investigated. Intrinsically rounded specific-heat anomalies are observed at 1.4 and 0.9 K, respectively, over extended density regions in between the liquid and incommensurate ... More
New Heat-Capacity Measurements of the Possible Order-Disorder Transition in the 4/7-phase of 2D HeliumOct 01 2012We have developed a new heat-capacity measuring system with ZYX graphite that is known to have much better crystallinity than Grafoil and started data collection. We report preliminary data as well as a detailed description of instrumentation including ... More
Millikelvin LEED apparatus: a feasibility studyOct 02 2012A low-energy electron diffraction (LEED) apparatus which works at temperatures down to about 100 mK is designed to obtain structural information of 2D helium on graphite. This very low temperature system can be realized by reducing the thermal inflow ... More
Preliminary Heat Capacity and Vapor Pressure Measurements of 2D 4He on ZYX GraphiteJul 16 2012Dec 11 2012We report preliminary heat capacity and vapor pressure measurements of the first and second layers of 4He adsorbed on ZYX graphite. ZYX is known to have much better crystallinity than Grafoil, the most commonly-used exfoliated graphite substrate, such ... More
Hyper Extremely Red Objects in the Subaru Deep Field: Evidence for Primordial Elliptical Galaxies in the Dusty Starburst PhaseAug 08 2001We report observational analyses and theoretical interpretations of unusually red galaxies in the Subaru Deep Field (SDF). A careful analysis of the SDF data revealed a population with unusually red near-infrared (NIR) colors of J - K >~ 3-4, with higher ... More
Evolution of tetragonal phase in the FeSe wire fabricated by a novel chemical-transformation PIT processJun 20 2011We fabricated superconducting FeSe wires by the chemical-transformation PIT process. The obvious correlation between annealing temperature and phase transformation was observed. Annealing above 500^{\circ}C produced wire-core transformation from hexagonal ... More
A study of topological vertexing for heavy quark taggingFeb 09 2001We compare heavy quark tagging and anti-tagging efficiencies for vertex detectors with different inner raddi using the topological vertex technique developed at the SLC/SLD experiment. Charm tagging benefits by going to very small inner radii.
Transport properties of the single- and 3-core Fe-Se wires fabricated by a novel chemical-transformation PIT processJun 17 2011We fabricated single- and 3-core superconducting Fe-Se wires using a novel process based on a chemical transformation from hexagonal FeSe1+d (non-superconducting) to tetragonal FeSe (superconducting) via an optimal supply of Fe from the Fe sheath by annealing. ... More
Morphologies of Two Massive Old Galaxies at z ~ 2.5Oct 02 2007Oct 04 2007We present the results of NICMOS imaging of two massive galaxies photometrically selected to have old stellar populations at z ~ 2.5. Both galaxies are dominated by apparent disks of old stars, although one of them also has a small bulge comprising about ... More
Universal behavior of relaxational heterogeneity in glasses and liquidsMay 04 2000We report an investigation of the heterogeneity in super-cooled liquids and glasses using the non-Gaussianity parameter. We simulate selenium and a binary Lennard-Jones system by molecular dynamics. In the non-Gaussianity three time domains can be distinguished. ... More
Skewness and kurtosis as locally best invariant tests of normalityAug 20 2006Consider testing normality against a one-parameter family of univariate distributions containing the normal distribution as the boundary, e.g., the family of $t$-distributions or an infinitely divisible family with finite variance. We prove that under ... More
When are n-syzygy modules n-torsionfree?Apr 13 2016Let R be a commutative noetherian ring. We consider the question of when n-syzygy modules over R are n-torsionfree in the sense of Auslander and Bridger. Our tools include Serre's condition and certain conditions on the local Gorenstein property of R. ... More
Hyperbolic localization and Lefschetz fixed point formulas for higher-dimensional fixed point setsApr 16 2015May 25 2015We study Lefschetz fixed point formulas for constructible sheaves with higher-dimensional fixed point sets. Under fairly weak assumptions, we prove that the local contributions from them are expressed by some constructible functions associated to hyperbolic ... More
Heat Capacity study of $β$-FeSi$_2$ single crystalsJan 31 2006Heat Capacity of needle-like [length=5mm, diameter=1 mm] $\beta$-FeSi$_{2}$ single crystal, grown by chemical vapor transport has been measured. Two anomalies are found, a broad deviation centered around 160 K and a clear deviation at a temperature of ... More
A Neural Chaos Model of Multistable PerceptionFeb 24 2000Feb 26 2000We present a perception model of ambiguous patterns based on the chaotic neural network and investigate the characteristics through computer simulations. The results induced by the chaotic activity are similar to those of psychophysical experiments and ... More