Exploration of Resonant Continuum and Giant Resonance in the Relativistic Approach

Single-particle resonant-states in the continuum are determined by solving scattering states of the Dirac equation with proper asymptotic conditions in the relativistic mean field theory (RMF). The regular and irregular solutions of the Dirac equation at a large radius where the nuclear potentials vanish are relativistic Coulomb wave functions, which are calculated numerically. Energies, widths and wave functions of single-particle resonance states in the continuum for ^{120}Sn are studied in the RMF with the parameter set of NL3. The isoscalar giant octupole resonance of ^{120}Sn is investigated in a fully consistent relativistic random phase approximation. Comparing the results with including full continuum states and only those single-particle resonances we find that the contributions from those resonant-states dominate in the nuclear giant resonant processes.Comment: 16 pages, 2 figure

Shifting RbR_b with AFBbA^b_{FB}

Precision measurements at the $Z$ resonance agree well with the standard model. However, there is still a hint of a discrepancy, not so much in $R_b$ by itself (which has received a great deal of attention in the past several years) but in the forward-backward asymmetry $A^b_{FB}$ together with $R_b$. The two are of course correlated. We explore the possibilty that these and other effects are due to the mixing of $b_L$ and $b_R$ with one or more heavy quarks.Comment: 11 pages, 1 Figure, LaTex fil

Numerical framework for transcritical real-fluid reacting flow simulations using the flamelet progress variable approach

An extension to the classical FPV model is developed for transcritical real-fluid combustion simulations in the context of finite volume, fully compressible, explicit solvers. A double-flux model is developed for transcritical flows to eliminate the spurious pressure oscillations. A hybrid scheme with entropy-stable flux correction is formulated to robustly represent large density ratios. The thermodynamics for ideal-gas values is modeled by a linearized specific heat ratio model. Parameters needed for the cubic EoS are pre-tabulated for the evaluation of departure functions and a quadratic expression is used to recover the attraction parameter. The novelty of the proposed approach lies in the ability to account for pressure and temperature variations from the baseline table. Cryogenic LOX/GH2 mixing and reacting cases are performed to demonstrate the capability of the proposed approach in multidimensional simulations. The proposed combustion model and numerical schemes are directly applicable for LES simulations of real applications under transcritical conditions.Comment: 55th AIAA Aerospace Sciences Meeting, Dallas, T

A Study of Gluon Propagator on Coarse Lattice

We study gluon propagator in Landau gauge with lattice QCD, where we use an improved lattice action. The calculation of gluon propagator is performed on lattices with the lattice spacing from 0.40 fm to 0.24 fm and with the lattice volume from $(2.40 fm)^4$ to $(4.0 fm)^4$. We try to fit our results by two different ways, in the first one we interpret the calculated gluon propagators as a function of the continuum momentum, while in the second we interpret the propagators as a function of the lattice momentum. In the both we use models which are the same in continuum limit. A qualitative agreement between two fittings is found.Comment: Revtex 14pages, 11 figure

Dissipate locally, couple globally: a sharp transition from decoupling to infinite range coupling in Josephson arrays with on-site dissipation

We study the T=0 normal to superconducting transition of Josephson arrays with {\it on-site} dissipation. A perturbative renormalization group solution is given. Like the previously studied case of {\it bond} dissipation (BD), this is a "floating" to coupled (FC) phase transition. {\it Unlike} the BD transition, at which {\it only} nearest-neighbor couplings become relevant, here {\it all} inter-grain couplings, out to {\it infinitely} large distances, do so simultaneously. We predict, for the first time in an FC transition, a diverging spatial correlation length. Our results show the robustness of floating phases in dissipative quantum systems.Comment: 7+ pages, 3 eps figures, Europhysics Letters preprint format, as publishe

Does Every Quasar Harbor A Blazar?

Assuming there is a blazar type continuum in every radio-loud quasar, we find that the free-free heating due to the beamed infrared continuum can greatly enhance collisionally excited lines, and thus explain the stronger CIV $\lambda$1549 line emission observed in radio loud quasars. We further predict that the CIV line should show variability {\it not} associated with observed continuum or Ly$\alpha$ variability.Comment: 15 pages, 3 figures; to appear in Astrophys. J. Let

Decay of the Z Boson into Scalar Particles

In extensions of the standard model, light scalar particles are often possible because of symmetry considerations. We study the decay of the Z boson into such particles. In particular, we consider for illustration the scalar sector of a recently proposed model of the 17-keV neutrino which satisfies all laboratory, astrophysical, and cosmological constraints.Comment: 11 pages (2 figures, not included) (Revised, Oct 1992). Some equations have been corrected and 1 figure has been eliminate

Dynamics of the Lyman alpha and C IV emitting gas in 3C 273

In this paper we study the variability properties of the Lyman alpha and C IV emission lines in 3C273 using archival IUE observations. Our data show for the first time the existence of variability on time scales of several years. We study the spatial distribution and the velocity field of the emitting gas by performing detailed analyses on the line variability using correlations, 1D and 2D response functions, and principal component analysis. In both lines we find evidence for two components, one which has the dynamic properties of gas in Keplerian motion around a black hole with a mass of the order of 10^9 Mo, and one which is characterized by high, blue-shifted velocities at large lag. There is no indication of the presence of optically thick emission medium neither in the Lya, nor in the Civ response functions. The component characterized by blue-shifted velocities, which is comparatively much stronger in Civ than in Lya, is more or less compatible with being the result of gas falling towards the central black hole with free-fall acceleration. We propose however that the line emission at high, blue-shifted velocities is better explained in terms of entrainment of gas clouds by the jet. This gas is therefore probably collisionally excited as a result of heating due to the intense infrared radiation from the jet, which would explain the strength of this component in Civ relative to Lya. This phenomenon might be a signature of disk-jet interaction.Comment: 16 pages, 10 figures. Accepted for publication in ApJ. Uses aaste

Energy scale independence of Koide's relation for quark and lepton masses

Koide's mass relation of charged leptons has been extended to quarks and neutrinos, and we prove here that this relation is independent of energy scale in a huge energy range from $1 {GeV}$ to $2\times10^{16} {GeV}$. By using the parameters $k_u$, $k_d$ and $k_{\nu}$ to describe the deviations of quarks and neutrinos from the exact Koide's relation, we also check the quark-lepton complementarity of masses such as $k_{l}+k_{d} \approx k_{\nu}+k_{u} \approx 2$, and show that it is also independent (or insensitive) of energy scale.Comment: 16 Latex pages, 2 figures, final version to appear in PR