Results for "W. M. Chen"

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New advances in dual reciprocity and boundary-only RBF methodsJul 04 2002This paper made some significant advances in the dual reciprocity and boundary-only RBF techniques. The proposed boundary knot method (BKM) is different from the standard boundary element method in a number of important aspects. Namely, it is truly meshless, ... More
A meshless, integration-free, and boundary-only RBF techniqueJul 11 2002Based on the radial basis function (RBF), non-singular general solution and dual reciprocity method (DRM), this paper presents an inherently meshless, integration-free, boundary-only RBF collocation techniques for numerical solution of various partial ... More
Relationship between boundary integral equation and radial basis functionJul 04 2002This paper aims to survey our recent work relating to the radial basis function (RBF) from some new views of points. In the first part, we established the RBF on numerical integration analysis based on an intrinsic relationship between the Green's boundary ... More
New Insights in Boundary-only and Domain-type RBF MethodsJul 04 2002This paper has made some significant advances in the boundary-only and domain-type RBF techniques. The proposed boundary knot method (BKM) is different from the standard boundary element method in a number of important aspects. Namely, it is truly meshless, ... More
Two-Loop Finiteness of Chern-Simons Field Theory in Background Field MethodJul 28 1996Mar 21 1998We perform two-loop calculation of Chern-Simons in background field method using the hybrid regularization of higher-covariant derivative and dimensional regularization. It is explicitly shown that Chern-Simons field theory is finite at the two-loop level. ... More
Stability of Emergent Kinetics in Optical Lattices with Artificial Spin-Orbit CouplingJun 30 2016Nov 04 2016Artificial spin-orbit coupling in optical lattices can be engineered to tune band structure into extreme regimes where the single-particle band flattens leaving only inter-particle interactions to define many-body states of matter. Lin et al. [Phys. Rev. ... More
Inconsistency of Naive Dimensional Regularizations and Quantum Correction to Non-Abelian Chern-Simons-Matter Theory RevisitedJun 16 1998We find the inconsistency of dimensional reduction and naive dimensional regularization in their applications to Chern-Simons type gauge theories. Further we adopt a consistent dimensional regularization to investigate the quantum correction to non-Abelian ... More
Superconformal Anomaly from AdS/CFT CorrespondenceDec 04 2003For a classical superconformal gauge theory in a conformal supergravity background, its chiral R-symmetry anomaly, Weyl anomaly and super-Weyl anomaly constitute a supermultiplet. We review how these anomalies arise from the five-dimensional gauged supergravity ... More
Stability of Emergent Kinetics in Optical Lattices with Artificial Spin-Orbit CouplingJun 30 2016Artificial spin-orbit coupling in optical lattices can be engineered to tune band structure into extreme regimes where the single-particle band flattens leaving only inter-particle interactions to define many-body states of matter. Lin et al. [Phys. Rev. ... More
The Holographic Supercurrent AnomalyApr 28 2003Nov 19 2003The \gamma-trace anomaly of supersymmetry current in a supersymmetric gauge theory shares a superconformal anomaly multiplet with the chiral R-symmetry anomaly and the Weyl anomaly, and its holographic reproduction is a valuable test to the AdS/CFT correspondence ... More
The Dying Wind Around HD 56126, A Post-AGB Carbon StarOct 02 2000We have used the Keck I telescope to resolve at mid-infrared wavelengths the dust emission from HD 56126 (IRAS 07134+1005), a post-Asymptotic Giant Branch carbon star with a detached dust shell. The gross morphology of the image can be explained by a ... More
$D_{sJ}$(2317) meson production at RHICMay 11 2007Production of $D_{sJ}$(2317) mesons in relativistic heavy ion collisions at RHIC is studied. Using the quark coalescence model, we first determine the initial number of $D_{sJ}$(2317) mesons produced during hadronization of created quark-gluon plasma. ... More
New Superconformal Field Theories in Four Dimensions and N=1 DualityJul 31 2000Recently, developments in the understanding of low-energy N=1 supersymmetric gauge theory have revealed two important phenomena: the appearance of new four-dimensional superconformal field theories and a non-Abelian generalization of electric-magnetic ... More
A Down to Earth Attempt at Determining the Low Energy Effective Action of N=2 Supersymmetric Yang-Mills TheoryJun 18 1999We review a detailed investigation of the perturbative part of the low-energy effective action of N=2 supersymmetric Yang-Mills theory in a conventional effective field theory approach. With the restriction that the effective action should contain at ... More
Semiparametric estimation of fractional cointegrating subspacesAug 01 2007We consider a common-components model for multivariate fractional cointegration, in which the $s\geq1$ components have different memory parameters. The cointegrating rank may exceed 1. We decompose the true cointegrating vectors into orthogonal fractional ... More
On the Low-Energy Effective Action of N=2 Supersymmetric Yang-Mills TheoryMar 19 1998We investigate the perturbative part of Seiberg's low-energy effective action of N=2 supersymmetric Yang-Mills theory in Wess-Zumino gauge in the conventional effective field theory technique. Using the method of constant field approximation and restricting ... More
Effects of Trilinear Term in Softly Broken N=1 Supersymmetric QCDJan 31 2000Softly broken dual magnetic theory of N=1 supersymmetric SU(N_c) QCD with N_f flavours is investigated with the inclusion of trilinear coupling term of scalar fields in the case of N_f>N_c+1. It is found that the trilinear soft supersymmetric breaking ... More
Gauss-Green theorem for weakly differentiable vector fields, sets of finite perimeter, and balance lawsSep 24 2007We analyze a class of weakly differentiable vector fields (\FF \colon \rn \to \rn) with the property that (\FF\in L^{\infty}) and (\div \FF) is a Radon measure. The primary focus of our investigation is to introduce a suitable notion of the normal trace ... More
Eta absorption by mesonsMay 27 2005Dec 12 2005Using the $[SU(3)_{\mathrm{L}} \times SU(3)_{\mathrm{R}}]_{\mathrm{global}% }\times [SU(3)_V]_{\mathrm{local}}$ chiral Lagrangian with hidden local symmetry, we evaluate the cross sections for the absorption of eta meson ($% \eta$) by pion ($\pi$), rho ... More
Boundary knot method for Laplace and biharmonic problemsJul 28 2003The boundary knot method (BKM) [1] is a meshless boundary-type radial basis function (RBF) collocation scheme, where the nonsingular general solution is used instead of fundamental solution to evaluate the homogeneous solution, while the dual reciprocity ... More
Soft matter and fractional mathematics: insights into mesoscopic quantum and time-space structuresMay 16 2004Recent years have witnessed a great research boom in soft matter physics. by now, most advances, however, are of either empirical results or purely mathematical extensions. The major obstacle is lacking of insights into fundamental phsysical laws underlying ... More
A novel methodology of weighted residual for nonlinear computationsMay 02 1999One of strengths in the finite element (FE) and Galerkin methods is their capability to apply weak formulations via integration by parts, which leads to elements matching at lower degree of continuity and relaxes requirements of choosing basis functions. ... More
An explanation of infrared catastrophe of 1/f power spectraMay 09 2003Chen [1] builds the intrinsic link between the 1/f power spectra and the acoustic frequency power law dissipation and, accordingly, presents two explanations of the so-called infrared catastrophe of the 1/f power spectra. This note is an immediate follow-up. ... More
Some recent advances on the RBFJul 26 2002This paper aims to survey our recent work relating to the radial basis function (RBF) and its applications to numerical PDEs. We introduced the kernel RBF involving general pre-wavelets and scale-orthogonal wavelets RBF. A dimension-independent RBF error ... More
Positive time fractional derivativeOct 07 2002In mathematical modeling of the non-squared frequency-dependent diffusions, also known as the anomalous diffusions, it is desirable to have a positive real Fourier transform for the time derivative of arbitrary fractional or odd integer order. The Fourier ... More
A new definition of the fractional LaplacianSep 18 2002It is noted that the standard definition of the fractional Laplacian leads to a hyper-singular convolution integral and is also obscure about how to implement the boundary conditions. This purpose of this note is to introduce a new definition of the fractional ... More
A direct time-domain FEM modeling of broadband frequency-dependent absorption with the presence of matrix fractional power: Model IAug 20 2002The frequency-dependent attenuation of broadband acoustics is often confronted in many different areas. However, the related time domain simulation is rarely found in literature due to enormous technical difficulty. The currently popular relaxation models ... More
Pseudo-Newton method for nonlinear equationsJun 09 1999In order to avoid the evaluation of the Jacobian matrix and its inverse, the present author recently introduced the pseudo-Jacobian matrix with a general applicability of any nonlinear systems of equations. By using this concept, this paper proposes the ... More
Levy stable distribution and [0,2] power law dependence of acoustic absorption on frequencyMay 09 2005The absorption of acoustic wave propagation in a broad variety of lossy media is characterized by an empirical power law function of frequency, w^y. It has long been noted that exponent y ranges from 0 to 2 for diverse media. Recently, the present author ... More
A modified BFGS quasi-Newton iterative formulaJul 14 1999The quasi-Newton equation is the very basis of a variety of the quasi-Newton methods. By using a relationship formula between nonlinear polynomial equations and the corresponding Jacobian matrix. presented recently by the present author, we established ... More
A new definition of nonlinear statistics mean and varianceJul 24 1999This note presents a new definition of nonlinear statistics mean and variance to simplify the nonlinear statistics computations. These concepts aim to provide a theoretical explanation of a novel nonlinear weighted residual methodology presented recently ... More
Mesoscopic Fractional Quantum in Soft MatterMay 09 2005Soft matter (e.g., biomaterials, polymers, sediments, oil, emulsions) has become an important bridge between physics and diverse disciplines. Its fundamental physical mechanism, however, is largely obscure. This study made the first attempt to connect ... More
A note on fractional derivative modeling of broadband frequency-dependent absorption: Model IIIAug 08 2002By far, the fractional derivative model is mainly related to the modelling of complicated solid viscoelastic material. In this study, we try to build the fractional derivative PDE model for broadband ultrasound propagation through human tissues.
1/f spectral trend and frequency power law of lossy mediaMay 07 2003The dissipation of acoustic wave propagation has long been found to obey an empirical power function of frequency, whose exponent parameter varies through different media. This note aims to unveil the inherent relationship between this dissipative frequency ... More
Time-space fabric underlying anomalous diffusionMay 08 2005This study unveils the time-space transforms underlying anomalous diffusion process. Based on this finding, we present the two hypotheses concerning the effect of fractal time-space fabric on physical behaviors and accordingly derive fractional quantum ... More
Active Galactic Nuclei with Double-peaked Narrow Lines: Are They Dual AGNs?Oct 04 2009Double-peaked [O III]5007, profiles in active galactic nuclei (AGNs) may provide evidence for the existence of dual AGNs, but a good diagnostic for selecting them is currently lacking. Starting from $\sim$ 7000 active galaxies in SDSS DR7, we assemble ... More
Extremely Sub-wavelength Planar Magnetic MetamaterialsNov 08 2011Jun 21 2012We present highly sub-wavelength magnetic metamaterials designed for operation at radio frequencies (RFs). A dual layer design consisting of independent planar spiral elements enables experimental demonstration of a unit cell size (a) that is ~ 700 times ... More
A note on radial basis function computingJun 03 2001This note carries three purposes involving our latest advances on the radial basis function (RBF) approach. First, we will introduce a new scheme employing the boundary knot method (BKM) to nonlinear convection-diffusion problem. It is stressed that the ... More
Helium star evolutionary channel to super-Chandrasekhar mass type Ia supernovaeJul 27 2010Jan 21 2011Recent discovery of several overluminous type Ia supernovae (SNe Ia) indicates that the explosive masses of white dwarfs may significantly exceed the canonical Chandrasekhar mass limit. Rapid differential rotation may support these massive white dwarfs. ... More
Mission: Impossible (Escape from the Lyman Limit)Mar 13 2003We investigate the intrinsic opacity of high-redshift galaxies to outgoing ionising photons using high-quality photometry of a sample of 27 spectroscopically-identified galaxies of redshift 1.9<z<3.5 in the Hubble Deep Field. Our measurement is based ... More
Precise QCD predictions for the production of Higgs+jet final statesAug 22 2014We compute the cross section and differential distributions for the production of a Standard Model Higgs boson in association with a hadronic jet to next-to-next-to-leading order in quantum chromodynamics (QCD). In Higgs boson studies at the LHC, final ... More
Roughness with a finite correlation length in the MicrotrapMar 30 2010We analyze the effects of roughness in the magnitude of the magnetic field produced by a current carrying microwire, which is caused by geometric fluctuation of the edge of wire. The relation between the fluctuation of the trapping potential and the height ... More
Collinear to Anti-collinear Quantum Phase Transition by VacanciesApr 11 2011Apr 13 2011We study static vacancies in the collinear magnetic phase of a frustrated Heisenberg $J_1$-$J_2$ model. It is found that vacancies can rapidly suppress the collinear antiferromagnetic state (CAFM)and generate a new magnetic phase, an anti-collinear magnetic ... More
The Duty-cycle of Gamma-ray Blazars: a New Approach, New ResultsNov 15 2004We study several properties of blazars detected in the gamma-ray energy range by comparing the EGRET sources with a sample of radio blazars which can be considered possible gamma-ray candidates. We define three classes: non-gamma-ray blazars, blazars ... More
Quantum Phase Transition in Ultracold 87Rb Atom Gas with Radiant FieldAug 11 2006A second-order quantum phase transition in two-species Bose-Einstein condensates of 87Rb atoms coupled by a quantized radiant field is revealed explicitly in terms of the energy spectrum which is obtained in the thermodynamic limit and is controllable ... More
On Dissipative Nonlinear Evolutional Pseudo-Differential EquationsAug 31 2017First, using the uniform decomposition in both physical and frequency spaces, we obtain an equivalent norm on modulation spaces. Secondly, we consider the Cauchy problem for the dissipative evolutionary pseudo-differential equation \partial_t u + A(x,D) ... More
Two-Loop Quantum Corrections of Scalar QED with Non-Minimal Chern-Simons CouplingMay 24 1999Sep 16 1999We investigate two-loop quantum corrections to non-minimally coupled Maxwell-Chern-Simons theory. The non-minimal gauge interaction represents the magnetic moment interaction between the charged scalar and the electromagnetic field. We show that the one-loop ... More
Spontaneous Scale Symmetry Breaking in 2+1-Dimensional QED at Both Zero and Finite TemperatureApr 20 2000A complete analysis of dynamical scale symmetry breaking in 2+1-dimensional QED at both zero and finite temperature is presented by looking at solutions to the Schwinger-Dyson equation. In different kinetic energy regimes we use various numerical and ... More
Implementation of three-qubit Grover search in cavity QEDJul 03 2007Using resonant interaction of three Rydberg atoms with a single-mode microwave cavity, we consider a realization of three-qubit Grover search algorithm in the presence of weak cavity decay, based on a previous idea for three-qubit quantum gate [Phys. ... More
Field-induced local moments around nonmagnetic impurities in metallic cupratesOct 30 2007We consider a defect in a strongly correlated host metal and discuss, within a slave boson mean field formalism for the $t-t'-J$ model, the formation of an induced paramagnetic moment which is extended over nearby sites. We study in particular an impurity ... More
Contact Binary Variables as X-ray SourcesAug 30 2005We present cross-identification of archived X-ray point sources with W UMa variable stars found in the All-Sky Automated Survey (ASAS). In a surveyed sky area of 300 square degrees of ASAS, 36 W UMa stars have been found associated with X-ray emission. ... More
On Quantum Corrections to Chern-Simons Spinor ElectrodynamicsJun 10 1997Jul 01 1997We make a detailed investigation on the quantum corrections to Chern-Simons spinor electrodynamics. Starting from Chern-Simons spinor quantum electrodynamics with the Maxwell term $-1/(4\gamma){\int}d^3x F_{\mu\nu}F^{\mu\nu}$ and by calculating the vacuum ... More
Gauss Law Constraints in Chern-Simons Theory From BRST QuantizationMay 21 1996Jul 28 1996The physical state condition in the BRST quantization of Chern-Simons field theory is used to derive Gauss law constraints in the presence of Wilson loops, which play an important role in explicitly establishing the connection of Chern-Simons field theory ... More
Hamiltonian chaos in a coupled BEC -- optomechanical cavity systemSep 29 2009We study a hybrid optomechanical system consisting of a Bose-Einstein condensate (BEC) trapped inside a single-mode optical cavity with a moving end-mirror. The intracavity light field has a dual role: it excites a momentum side-mode of the condensate, ... More
Tests of a High Resolution Time of Flight System Based on Long and Narrow ScintillatorJun 16 1996We have tested a prototype time-of-flight system based on bulk scintillator block of dimensions $2.5 \times 2.5 \times 200$ cm. Using a calibration scheme similar to the one used in actual collider experiments, we have achieved a resolution of 71 ps using ... More
Analysis of a selected sample of RR Lyrae stars in LMC from OGLE IIIAug 23 2012A systematic study of RR Lyrae stars is performed based on a selected sample of 655 objects in the Large Magellanic Cloud with observation of long span and numerous measurements by the Optical Gravitational Lensing Experiment III project. The Phase Dispersion ... More
Differential Regularization of Chern-Simons-Maxwell Spinor and Scalar ElectrodynamicsMar 31 1997Jul 14 1997Differential regularization is used to investigate the one-loop quantum corrections to Chern-Simons-Maxwell spinor and scalar electrodynamics. We illustrate the techniques to write the loop amplitudes in coordinate space. The short-distance expansion ... More
Theory of Resistivity Upturns in Metallic CupratesMay 10 2009We propose that the experimentally observed resistivity upturn of cuprates at low temperatures may be explained by properly accounting for the effects of disorder in a strongly correlated metallic host. Within a calculation of the DC conductivity using ... More
Classical dynamics of the optomechanical modes of a Bose-Einstein condensate in a ring cavityFeb 23 2010We consider a cavity optomechanical system consisting of a Bose-Einstein condensate (BEC) interacting with two counterpropagating traveling-wave modes in an optical ring cavity. In contrast to the more familiar case where the condensate is driven by the ... More
Radiatively Induced Lorentz and CPT Violation in Schwinger Constant Field ApproximationOct 16 2000Dec 15 2000The Schwinger proper-time method is an effective calculation method, explicitly gauge invariant and nonperturbative. We make use of this method to investigate the radiatively induced Lorentz and CPT-violating effects in quantum electrodynamics when an ... More
A Universal Phase Diagram for PMN-xPT and PZN-xPTApr 11 2003The phase diagram of the Pb(Mg1/3Nb2/3)O3 and PbTiO3 solid solution (PMN-xPT) indicates a rhombohedral ground state for x < 0.32. X-ray powder measurements by Dkhil et al. show a rhombohedrally split (222) Bragg peak for PMN-10%PT at 80 K. Remarkably, ... More
Gauge invariance, Lorentz covariance and canonical quantization in nucleon structure studiesNov 01 2014There are different operators of quark and gluon momenta, orbital angular momenta, and gluon spin in the nucleon structure study. The precise meaning of these operators are studied based on gauge invariance, Lorentz covariance and canonical quantization ... More
High-energy-density electron-positron pair plasma production and its dynamics in the relativistic transparency regimeJun 22 2017High-energy-density electron-positron pair plasma production and its dynamics in a thin foil illuminated by two counter-propagating laser pulses are investigated through multi-dimensional particle-in-cell simulations. We compare the production of electron-positron ... More
A new activity phase of the blazar 3C 454.3. Multifrequency observations by the WEBT and XMM-Newton in 2007-2008Oct 14 2008We present and analyse the WEBT multifrequency observations of 3C 454.3 in the 2007-2008 observing season, including XMM-Newton observations and near-IR spectroscopic monitoring, and compare the recent emission behaviour with the past one. In the optical ... More
Doping and Temperature Dependence of Raman Scattering of NdFeAsO1-xFx (x=0.0, 0.1, 0.2) SuperconductorSep 09 2008Raman spectra of polycrystalline NdFeAsO1-xFx (x=0.0, 0.1, 0.2) compound have been systematically investigated as functions of temperature and fluorine concentration. Scanning electron microscopic and Raman microscopic characterization demonstrates that ... More
Search for the Signatures of a New-Born Black Hole from the Collapse of a Supra-massive Millisecond Magnetar in Short GRB Light CurvesDec 12 2017`Internal plateau' followed by a sharp decay is commonly seen in short gamma-ray burst (GRB) light curves. The plateau component is usually interpreted as the dipole emission from a supra-massive magnetar, and the sharp decay may imply the collapse of ... More
Electronic Structure in Gapped Graphene with Coulomb PotentialApr 07 2008In this paper, we numerically study the bound electron states induced by long range Coulomb impurity in gapped graphene and the quasi-bound states in supercritical region based on the lattice model. We present a detailed comparison between our numerical ... More
High-energy emissions from the gamma-ray binary 1FGL J1018.6-5856Mar 23 2017The gamma-ray binary 1FGL J1018.6-5856 is known to be composed of a massive star with a compact object with an orbital period of 16.54 days. We study mechanisms of high-energy emissions (X-ray, GeV, and TeV $\gamma$-rays) from this binary system. The ... More
Non-adiabatic topological spin pumpingJan 13 2016Based on the Floquet scattering theory, we analytically investigate the topological spin pumping for an exactly solvable model. Floquet spin Chern numbers are introduced to characterize the periodically time-dependent system. The topological spin pumping ... More
Bell violation versus geometric measure of quantum discord and their dynamical behaviorMar 20 2013Motivated by recent numerous works on the interplay among various measures of quantum correlations, we aim to investigate the relationship between the violation of Clauser-Horne-Shimony-Holt (CHSH) Bell inequality and geometric measure of quantum discord ... More
The Color Excesses of Type Ia Supernovae from Single-Degenerate Channel ModelJul 16 2009Single Degenerate model is the most widely accepted progenitor model of type Ia supernovae (SNe Ia), in which a carbon-oxygen white dwarf (CO WD) accretes hydrogen-rich material from a main sequence or a slightly evolved star (WD +MS) to increase its ... More
Collimated Ultra-Bright Gamma-Rays from a PW-Laser-Driven Wire WigglerOct 31 2017Feb 16 2018It is shown by three-dimensional QED particle-in-cell simulation that as a laser pulse of 2.5 PW and 20 fs propagates along a sub-wavelength-wide solid wire, directional synchrotron $\gamma-$rays along the wire surface can be efficiently generated. With ... More
π-Plasmon Dispersion in Free-Standing Graphene by Momentum-Resolved Electron Energy-Loss SpectroscopyDec 30 2014The {\pi}-plasmon dispersion in graphene was scrutinized by momentum(q)-resolved electron energy-loss spectroscopy with an improved q resolution and found to display the square root of q dispersion characteristic of the collective excitation of two-dimensional ... More
The mode switching of PSR B2020+28May 21 2016This paper reports on polarimetric radiation properties based on the switching modes of normal PSR B2020+28 by analysing the data acquired from the Nanshan 25-m radio telescope at 1556 MHz. With nearly 8 hours quasi-continuous observation, the data presented ... More
Epitaxial GaN Nanorods via Catalytic Capillary CondensationMar 09 2005Intrinsic catalytic process by capillary condensation of Ga-atoms into nanotrenches, formed among impinging islands during the wurzite-GaN thin film deposition, is shown to be an effective path to growing GaN nanorods without metal catalysts. The nano-capillary ... More
Inelastic electron tunneling spectroscopy of nanoporous gold filmsJun 09 2014We investigated the localized electronic properties of nanoporous gold films by using an ultra-high vacuum scanning tunneling microscope at low temperature (4.2 K). Second derivative scanning tunneling spectroscopy shows the plasmon peaks of the nanoporous ... More
Problems related to gauge invariance and momentum, spin decomposition in nucleon structure studyDec 24 2013Dec 30 2013How do the quark and gluon share the nucleon momentum? How does the nucleon spin distribute among its constituents? What means the quark and gluon momentum, spin and orbital angular momentum? These problems are analyzed and a solution is proposed based ... More
Electronic properties of germanene nanoribbons in external fieldsMay 13 2016Sep 22 2016Germanene nanoribbons, with buckled structures, exhibit unique electronic properties. The complicated relations among the quantum confinement, the spin-orbital coupling, the magnetic quantization, the electric-field dominated quantum numbers, energy dispersions, ... More
Gravity Dual of Superconformal AnomalyAug 16 2005Jul 18 2007The supergravity dual of superconformal anomaly in a four-dimensional supersymmetric gauge theory is investigated. We consider a well-established dual correspondence between the ${\cal N}=1$ $SU(N+M)\times SU(N)$ supersymmetric gauge theory with two flavors ... More
Evaluating the Maximum Likelihood Method for Detecting Short-Term Variability of AGILE gamma-ray SourcesJan 12 2012The AGILE space mission (whose instrument is sensitive in the energy ranges 18-60 keV, and 30 MeV - 50 GeV) has been operating since 2007. Assessing the statistical significance of time variability of gamma-ray sources above 100 MeV is a primary task ... More
CP-violating top quark couplings at future linear $e^+e^-$ collidersOct 18 2017We study the potential of future lepton colliders to probe violation of the CP symmetry in the top quark sector. In certain extensions of the Standard Model, such as the two-Higgs-doublet model (2HDM), sizeable anomalous top quark dipole moments can arise, ... More
Cavity QED characterization of many-body atomic states in double-well potentials -- The role of dissipationOct 31 2008Nov 04 2008When an incident light beam is scattered off a sample of ultracold atoms trapped in an optical lattice, the statistical properties of the retro-reflected field contain information about the quantum state of the atoms, and permit for example to distinguish ... More
Kerr-Schild Structure and Harmonic 2-forms on (A)dS-Kerr-NUT MetricsMay 31 2007Jun 19 2007We demonstrate that the general (A)dS-Kerr-NUT solutions in D dimensions with ([D/2], [(D+1)/2]) signature admit [D/2] linearly-independent, mutually-orthogonal and affinely-parameterised null geodesic congruences. This enables us to write the metrics ... More
A Note on the Radiatively Induced Lorentz and CPT Violated Chern-Simons-like Term in the Extended Quantum ElectrodynamicsDec 16 2007Jul 09 2009We show that the ambiguity for the Chern-Simons-like term induced from quantum correction in the extended QED should have nothing to do with the approximation on the exact fermionic propagator, contradictory to the claim in Ref.[19]. Further, we investigate ... More
New physical effects on the decay $B_{s(d)} \to γγ$ in the sequential fourth Generation modelJan 24 2011We study the contributions to the branching ratios of $B_{s(d)}\to \gamma \gamma$ decay in the sequential fourth generation model (SM4). We find that the theoretical values of the branching ratios, ${\rm BR}(B_{s(d)}\to\gamma\gamma)$, including the contributions ... More
Circumgalactic Pressure Profiles Indicate Precipitation-Limited Atmospheres for M_* ~ 10^9 - 10^11.5 M_SunFeb 28 2019Cosmic gas cycles in and out of galaxies, but outside of galaxies it is difficult to observe except for the absorption lines that circumgalactic clouds leave in the spectra of background quasars. Using photoionization modelling of those lines to determine ... More
A Lyapunov Formulation for Efficient Solution of the Poisson and Convection-Diffusion Equations by the Differential Quadrature MethodJul 09 2002Civan and Sliepcevich [1, 2] suggested that special matrix solver should be developed to further reduce the computing effort in applying the differential quadrature (DQ) method for the Poisson and convection-diffusion equations. Therefore, the purpose ... More
Physical interpretation of fractional diffusion-wave equation via lossy media obeying frequency power lawMar 17 2003The fractional diffusion-wave equation (FDWE) is a recent generalization of diffusion and wave equations via time and space fractional derivatives. The equation underlies Levy random walk and fractional Brownian motion and is foremost important in mathematical ... More
Fractional Laplacian, Levy stable distribution, and time-space models for linear and nonlinear frequency-dependent lossy mediaDec 30 2002The frequency-dependent attenuation typically obeys an empirical power law with an exponent ranging from 0 to 2. The standard time-domain partial differential equation models can describe merely two extreme cases of frequency independent and frequency-squared ... More
Studies of YBCO Strip Lines under Voltage Pulses: Optimisation of the Design of Fault Current LimitersJan 21 2003We present experimental results on the behaviour of a superconducting YBCO/Au meander of length L submitted to short circuit tests with constant voltage pulses. The meander, at the beginning of the short-circuit, is divided in two regions; one, with a ... More
Suppressed star formation in circumnuclear regions in Seyfert galaxiesApr 18 2007Feedback from black hole activity is widely believed to play a key role in regulating star formation and black hole growth. A long-standing issue is the relation between the star formation and fueling the supermassive black holes in active galactic nuclei ... More
The superconductor KxSr(1-x)Fe2As2: Normal state and superconducting propertiesFeb 27 2009The normal state and superconducting properties are investigated in the phase diagram of K_xSr_{1-x}Fe_2As_2 for 0<x<1. The ground state upper critical field, H_{c2}(0), is extrapolated from magnetic field dependent resistivity measurements. H_{c2}(0) ... More
The Study on the Nonlinear Computations of the DQ and DC MethodsApr 15 1999This paper points out that the differential quadrature (DQ) and differential cubature (DC) methods due to their global domain property are more efficient for nonlinear problems than the traditional numerical techniques such as finite element and finite ... More
Dual reciprocity BEM and dynamic programming filter for inverse elastodynamic problemsJul 10 2002This paper presents the first coupling application of the dual reciprocity BEM (DRBEM) and dynamic programming filter to inverse elastodynamic problem. The DRBEM is the only BEM method, which does not require domain discretization for general linear and ... More
Gravitational Correspondence of Two Types of Superconformal AnomalyApr 23 2006In a classical conformal invariant supersymmetric gauge theory, the chiral R-symmetry current, the supersymmetry current and the energy-momentum tensor constitute a supercurrent multiplet. There are two different superconformal anoamly multiplets in four-dimensional ... More
Quantum Field Theory and Differential GeometryMar 10 2008Jun 12 2008We introduce the historical development and physical idea behind topological Yang-Mills theory and explain how a physical framework describing subatomic physics can be used as a tool to study differential geometry. Further, we emphasize that this phenomenon ... More
Two Interesting Properties of the Exponential DistributionMar 03 2015Let $X_1, X_2,\ldots, X_n$ be $n$ independent and identically distributed random variables, here $n \geq 2.$ Let $X_{(1)}, X_{(2)}, \ldots, X_{(n)}$ be the order statistics of $X_1, X_2,..., X_n.$ In this note we proved that: (I) If $X_1, X_2,..., X_n$ ... More
Modified Szabo's wave equation models for lossy media obeying frequency power lawDec 30 2002Szabo's models of acoustic attenuation (Szabo 1994a) comply well with the empirical frequency power law involving non-integer and odd integer exponent coefficients while guaranteering causality, but nevertheless encounter the troublesome issues of hyper-singular ... More
Magnetoplasmons in quasi-neutral epitaxial graphene nanoribbonsMay 21 2013Jun 29 2013We present infrared transmission spectroscopy study of the inter-Landau-level excitations in quasi-neutral epitaxial graphene nanoribbon arrays. We observed a substantial deviation in energy of the $L_{0(-1)}$$\to$$L_{1(0)}$ transition from the characteristic ... More
Spin dependent electron-phonon interaction in SmFeAsO by low-temperature Raman spectroscopySep 26 2010Oct 07 2010The interplay between spin dynamics and lattice vibration has been suggested as an important part of the puzzle of high-temperature superconductivity. Here we report the strong interaction between spin fluctuation and phonon in SmFeAsO, a parent compound ... More