Transport and interaction of a relativistic electron beam in low pressure neutral gases

International Nuclear Information System (INIS)

Iyyengar, S.K.; Rohatgi, V.K.

1989-01-01

A numerical study of the transport of a 0.27-MeV, 6.6-kA, 40-ns relativistic electron beam in argon and hydrogen in the pressure range of 0.01--1.0 Torr taking into account charge and current neutralization effects is presented. Ionization by avalanching and by beam and plasma electrons is included in the calculation of plasma density buildup. Plasma heating resulting from return current heating and two-stream instability is taken into account. The computed results of charge transport, net current, and breakdown time are compared with experimental results obtained in this laboratory. The results are in reasonable agreement with the experiment and show a maximum charge transport of 75% at the optimum pressure of 0.1 and 0.6 Torr in argon and hydrogen, respectively. The calculations indicate beam-generated plasma parameters of 10 19 --10 20 m -3 density and 1--5 eV electron temperature

Science, Neutrality and Objectivity in Nuclear Research: Shared References or Ideal Types?

International Nuclear Information System (INIS)

Bovy, Michel; Laes, Erik; Eggermont, Gilbert

2003-01-01

Science, neutrality and objectivity in nuclear research are shared references because they can be considered as useful ideal types to support the communication process. This doesn't mean these references are empty, or have no effects on the organizational level. But the expert needs to recognize which type of justification he's ready to share with others (should it be peers or other social actors) because he has to share two types of communication process. The closure is less in the object than in the acceptance of a shared ideal world justification. While the expert uses the methodology of science to focus on the relevancy of some means, the layman requires being part of their communication process before the black box is closed, not becoming a scientist himself. The gap can be reduced by a combined effort to open up the communication process to each other based on a justification principle that cannot be mastered in advance by one side. This clearly show us democracy is not a question only debated in the governmental spheres but also in new kind of Parliaments allowing exchanges and open discussions removed from some pre-determined roles play. This requires time and sufficient room of manoeuvre from both sides. For example, it means interactions conditioned by the urgent necessity to make acceptable some technical depository solution for nuclear waste build some communication walls in terms of justification. The whole design process of society sometimes is at stake because of some inherited justification principles making science, independence and neutrality responsible for our welfare and safety. A solution could consist of using this framework in the beginning of the process and not in an attempt to stop controversies when results are needed (as a depository for nuclear waste). Another one could consist of enlarging the actor-network to more actors bringing more justification principles and varied interests. This won't be seen as a search for more order but a

Relativistic total energy and chemical potential of heavy atoms and positive ions

International Nuclear Information System (INIS)

Hill, S.H.; Grout, P.J.; March, N.H.

1984-01-01

The relativistic Thomas-Fermi theory, with a finite nucleus, is used to study the variation of the chemical potential μ with atomic number Z and number of electrons N (N <= Z). The difference between the total energy of positive ions and that of the corresponding neutral atom has been obtained. The scaling predictions are confirmed by numerical calculations. The first principles calculation of the relativistic Thomas-Fermi total energy of neutral atoms is also studied. (author)

Draws on a relativistic pinch with a longitudinal magnetic field

International Nuclear Information System (INIS)

Trubnikov, B.A.

1991-01-01

The problems of draws on a relativistic pinch with longitudinal magnetic field are discussed. The absence of collisions promoting the energy exchange between different degrees of particle freedom is assumed. The calculations are conducted using the ideal relativistic anisotropic magnetic hydrodynamics equations. The spectrum of particles accelerated in the draws, is determined

Relativistic magnetohydrodynamics as a Hamiltonian system

International Nuclear Information System (INIS)

Holm, D.D.; Kupershmidt, A.

1985-01-01

The equations of ideal relativistic magnetohydrodynamics in the laboratory frame form a noncanonical Hamiltonian system with the same Poisson bracket as for the nonrelativistic system, but with dynamical variables and Hamiltonian obtained via a regular deformation of their nonrelativistic counterparts [fr

Viscous photons in relativistic heavy ion collisions

International Nuclear Information System (INIS)

Dion, Maxime; Paquet, Jean-Francois; Young, Clint; Jeon, Sangyong; Gale, Charles; Schenke, Bjoern

2011-01-01

Theoretical studies of the production of real thermal photons in relativistic heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) are performed. The space-time evolution of the colliding system is modelled using music, a 3+1D relativistic hydrodynamic simulation, using both its ideal and viscous versions. The inclusive spectrum and its azimuthal angular anisotropy are studied separately, and the relative contributions of the different photon sources are highlighted. It is shown that the photon v 2 coefficient is especially sensitive to the details of the microscopic dynamics like the equation of state, the ratio of shear viscosity over entropy density, η/s, and to the morphology of the initial state.

Relativistic density matrix in the diagonal momentum representation. Bose-gas

International Nuclear Information System (INIS)

Makhlin, A.N.; Sinyukov, Yu.M.

1984-01-01

The relativistic-invariance treatment of the ideal Bose-system arising from the diagonal momentum representation for the density matrix is developed. The average occupation members and their correlators for statistical systems in arbitrary inertial frames are found on the equal-time hypersurfaces. The relativistic partition function method for the calculation of thermodynamic properties of gases moving as a whole is constructed

Anandan quantum phase for a neutral particle with Fermi-Walker reference frame in the cosmic string background

International Nuclear Information System (INIS)

Bakke, Knut; Furtado, C.

2010-01-01

We study geometric quantum phases in the relativistic and non-relativistic quantum dynamics of a neutral particle with a permanent magnetic dipole moment interacting with two distinct field configurations in a cosmic string spacetime. We consider the local reference frames of the observers are transported via Fermi-Walker transport and study the influence of the non-inertial effects on the phase shift of the wave function of the neutral particle due to the choice of this local frame. We show that the wave function of the neutral particle acquires non-dispersive relativistic and non-relativistic quantum geometric phases due to the topology of the spacetime, the interaction between the magnetic dipole moment with external fields and the spin-rotation coupling. However, due to the Fermi-Walker reference frame, no phase shift associated to the Sagnac effect appears in the quantum dynamics of a neutral particle. We show that in the absence of topological defect, the contribution to the quantum phase due to the spin-rotation coupling is equivalent to the Mashhoon effect in non-relativistic dynamics. (orig.)

A Comprehensive Comparison of Relativistic Particle Integrators

Science.gov (United States)

Ripperda, B.; Bacchini, F.; Teunissen, J.; Xia, C.; Porth, O.; Sironi, L.; Lapenta, G.; Keppens, R.

2018-03-01

We compare relativistic particle integrators commonly used in plasma physics, showing several test cases relevant for astrophysics. Three explicit particle pushers are considered, namely, the Boris, Vay, and Higuera–Cary schemes. We also present a new relativistic fully implicit particle integrator that is energy conserving. Furthermore, a method based on the relativistic guiding center approximation is included. The algorithms are described such that they can be readily implemented in magnetohydrodynamics codes or Particle-in-Cell codes. Our comparison focuses on the strengths and key features of the particle integrators. We test the conservation of invariants of motion and the accuracy of particle drift dynamics in highly relativistic, mildly relativistic, and non-relativistic settings. The methods are compared in idealized test cases, i.e., without considering feedback onto the electrodynamic fields, collisions, pair creation, or radiation. The test cases include uniform electric and magnetic fields, {\\boldsymbol{E}}× {\\boldsymbol{B}} fields, force-free fields, and setups relevant for high-energy astrophysics, e.g., a magnetic mirror, a magnetic dipole, and a magnetic null. These tests have direct relevance for particle acceleration in shocks and in magnetic reconnection.

Specific heats of degenerate ideal gases

OpenAIRE

Caruso, Francisco; Oguri, Vitor; Silveira, Felipe

2017-01-01

From arguments based on Heisenberg's uncertainty principle and Pauli's exclusion principle, the molar specific heats of degenerate ideal gases at low temperatures are estimated, giving rise to values consistent with the Nerst-Planck Principle (third law of Thermodynamics). The Bose-Einstein condensation phenomenon based on the behavior of specific heat of massive and non-relativistic boson gases is also presented.

Diffeomorphism Group Representations in Relativistic Quantum Field Theory

Energy Technology Data Exchange (ETDEWEB)

Goldin, Gerald A. [Rutgers Univ., Piscataway, NJ (United States); Sharp, David H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-12-20

We explore the role played by the di eomorphism group and its unitary representations in relativistic quantum eld theory. From the quantum kinematics of particles described by representations of the di eomorphism group of a space-like surface in an inertial reference frame, we reconstruct the local relativistic neutral scalar eld in the Fock representation. An explicit expression for the free Hamiltonian is obtained in terms of the Lie algebra generators (mass and momentum densities). We suggest that this approach can be generalized to elds whose quanta are spatially extended objects.

Relativistic extension of a charge-conservative finite element solver for time-dependent Maxwell-Vlasov equations

Science.gov (United States)

Na, D.-Y.; Moon, H.; Omelchenko, Y. A.; Teixeira, F. L.

2018-01-01

Accurate modeling of relativistic particle motion is essential for physical predictions in many problems involving vacuum electronic devices, particle accelerators, and relativistic plasmas. A local, explicit, and charge-conserving finite-element time-domain (FETD) particle-in-cell (PIC) algorithm for time-dependent (non-relativistic) Maxwell-Vlasov equations on irregular (unstructured) meshes was recently developed by Moon et al. [Comput. Phys. Commun. 194, 43 (2015); IEEE Trans. Plasma Sci. 44, 1353 (2016)]. Here, we extend this FETD-PIC algorithm to the relativistic regime by implementing and comparing three relativistic particle-pushers: (relativistic) Boris, Vay, and Higuera-Cary. We illustrate the application of the proposed relativistic FETD-PIC algorithm for the analysis of particle cyclotron motion at relativistic speeds, harmonic particle oscillation in the Lorentz-boosted frame, and relativistic Bernstein modes in magnetized charge-neutral (pair) plasmas.

Pion production in relativistic collisions of nuclear drops

International Nuclear Information System (INIS)

Alonso, C.T.; Wilson, J.R.; McAbee, T.L.; Zingman, J.A.

1988-09-01

In a continuation of the long-standing effort of the nuclear physics community to model atomic nuclei as droplets of a specialized nuclear fluid, we have developed a hydrodynamic model for simulating the collisions of heavy nuclei at relativistic speeds. Our model couples ideal relativistic hydrodynamics with a new Monte Carlo treatment of dynamic pion production and tracking. The collective flow for low-energy (200 MeV/N) collisions predicted by this model compares favorably with results from earlier hydrodynamic calculations which used quite different numerical techniques. Our pion predictions at these lower energies appear to differ, however, from the experimental data on pion multiplicities. In this case of ultra-relativistic (200 GeV/N) collisions, our hydrodynamic model has produced baryonic matter distributions which are in reasonable agreement with recent experimental data. These results may shed some light on the sensitivity of relativistic collision data to the nuclear equation of state. 20 refs., 12 figs

Relativistic electron Wigner crystal formation in a cavity for electron acceleration

CERN Document Server

Thomas, Johannes; Pukhov, Alexander

2014-01-01

It is known that a gas of electrons in a uniform neutralizing background can crystallize and form a lattice if the electron density is less than a critical value. This crystallization may have two- or three-dimensional structure. Since the wake field potential in the highly-nonlinear-broken-wave regime (bubble regime) has the form of a cavity where the background electrons are evacuated from and only the positively charged ions remain, it is suited for crystallization of trapped and accelerated electron bunch. However, in this case, the crystal is moving relativistically and shows new three-dimensional structures that we call relativistic Wigner crystals. We analyze these structures using a relativistic Hamiltonian approach. We also check for stability and phase transitions of the relativistic Wigner crystals.

Particle-production mechanism in relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Bush, B.W.; Nix, J.R.

1994-01-01

We discuss the production of particles in relativistic heavy-ion collisions through the mechanism of massive bremsstrahlung, in which massive mesons are emitted during rapid nucleon acceleration. This mechanism is described within the framework of classical hadrodynamics for extended nucleons, corresponding to nucleons of finite size interacting with massive meson fields. This new theory provides a natural covariant microscopic approach to relativistic heavy-ion collisions that includes automatically spacetime nonlocality and retardation, nonequilibrium phenomena, interactions among all nucleons, and particle production. Inclusion of the finite nucleon size cures the difficulties with preacceleration and runaway solutions that have plagued the classical theory of self-interacting point particles. For the soft reactions that dominate nucleon-nucleon collisions, a significant fraction of the incident center-of-mass energy is radiated through massive bremsstrahlung. In the present version of the theory, this radiated energy is in the form of neutral scalar (σ) and neutral vector (ω) mesons, which subsequently decay primarily into pions with some photons also. Additional meson fields that are known to be important from nucleon-nucleon scattering experiments should be incorporated in the future, in which case the radiated energy would also contain isovector pseudoscalar (π + , π - , π 0 ), isovector scalar (δ + , δ - , δ 0 ), isovector vector (ρ + , ρ - , ρ 0 ), and neutral pseudoscalar (η) mesons

Notes on nonlocal projective measurements in relativistic systems

International Nuclear Information System (INIS)

Lin, Shih-Yuin

2014-01-01

In quantum mechanical bipartite systems, naive extensions of von Neumann’s projective measurement to nonlocal variables can produce superluminal signals and thus violate causality. We analyze the projective quantum nondemolition state-verification in a two-spin system and see how the projection introduces nonlocality without entanglement. For the ideal measurements of “R-nonlocal” variables, we argue that causality violation can be resolved by introducing further restrictions on the post-measurement states, which makes the measurement “Q-nonlocal”. After we generalize these ideas to quantum mechanical harmonic oscillators, we look into the projective measurements of the particle number of a single mode or a wave-packet of a relativistic quantum field in Minkowski space. It turns out that the causality-violating terms in the expectation values of the local operators, generated either by the ideal measurement of the “R-nonlocal” variable or the quantum nondemolition verification of a Fock state, are all suppressed by the IR and UV cutoffs of the theory. Thus relativistic quantum field theories with such projective measurements are effectively causal

Decoherence and discrete symmetries in deformed relativistic kinematics

Science.gov (United States)

Arzano, Michele

2018-01-01

Models of deformed Poincaré symmetries based on group valued momenta have long been studied as effective modifications of relativistic kinematics possibly capturing quantum gravity effects. In this contribution we show how they naturally lead to a generalized quantum time evolution of the type proposed to model fundamental decoherence for quantum systems in the presence of an evaporating black hole. The same structures which determine such generalized evolution also lead to a modification of the action of discrete symmetries and of the CPT operator. These features can in principle be used to put phenomenological constraints on models of deformed relativistic symmetries using precision measurements of neutral kaons.

Relativistic corrections for the conventional, classical Nyquist theorem

International Nuclear Information System (INIS)

Theimer, O.; Dirk, E.H.

1983-01-01

New expressions for the Nyquist theorem are derived under the condition in which the random thermal speed of electrons, in a system of charged particles, can approach the speed of light. Both the case in which, the electron have not drift velocity relative to the ions or neutral particles and the case in which drift occours are investigated. In both instances, the new expressions for the Nyquist theorem are found to contain relativistic correction terms; however for electron temperatures T approx. 10 9 K and drift velocity magnitudes w approx. 0.5c, where c is the speed of light, the effects of these correction terms are generally small. The derivation of these relativistic corrections is carried out by means of procedures developed in an earlier work. A relativistic distribution function, which incorporates a constant drift velocity with a random thermal velocity for a given particle species, is developed

Expressions for linearized perturbations in ideal-fluid cosmological models

International Nuclear Information System (INIS)

Ratra, B.

1988-01-01

We present closed-form solutions of the relativistic linear perturbation equations (in synchronous gauge) that govern the evolution of inhomogeneities in homogeneous, spatially flat, ideal-fluid, cosmological models. These expressions, which are valid for irregularities on any scale, allow one to analytically interpolate between the known approximate solutions which are valid at early times and at late times

Relativistic classical and quantum dynamics in intense crossed laser beams of various polarizations

Directory of Open Access Journals (Sweden)

M. Verschl

2007-02-01

Full Text Available The dynamics of an electron in crossed laser fields is investigated analytically. Two different standing wave configurations are compared. The counterpropagating laser waves are either linearly or circularly polarized. Both configurations have in common that there are one-dimensional trajectories on which the electron can oscillate with vanishing Lorentz force. The dynamics is analyzed for the situations when the electron moves in the vicinity of these ideal axes. If the laser intensities imply nonrelativistic electron dynamics, the system is described quantum mechanically. A semiclassical treatment renders the strongly relativistic regime accessible as well. To describe relativistic wave packets, the results of the classical analysis are employed for a Monte Carlo ensemble. This allows for a comparison of the wave packet dynamics for both configurations in the strongly relativistic regime. It is found for certain cases that relativity slows down the dynamics, i.e., for higher laser intensities, wave packet spreading and the drift away from the ideal axis of vanishing Lorentz force are shown to be increasingly suppressed.

Statistical thermodynamics of a two-dimensional relativistic gas.

Science.gov (United States)

Montakhab, Afshin; Ghodrat, Malihe; Barati, Mahmood

2009-03-01

In this paper we study a fully relativistic model of a two-dimensional hard-disk gas. This model avoids the general problems associated with relativistic particle collisions and is therefore an ideal system to study relativistic effects in statistical thermodynamics. We study this model using molecular-dynamics simulation, concentrating on the velocity distribution functions. We obtain results for x and y components of velocity in the rest frame (Gamma) as well as the moving frame (Gamma;{'}) . Our results confirm that Jüttner distribution is the correct generalization of Maxwell-Boltzmann distribution. We obtain the same "temperature" parameter beta for both frames consistent with a recent study of a limited one-dimensional model. We also address the controversial topic of temperature transformation. We show that while local thermal equilibrium holds in the moving frame, relying on statistical methods such as distribution functions or equipartition theorem are ultimately inconclusive in deciding on a correct temperature transformation law (if any).

Effects of errors in velocity tilt on maximum longitudinal compression during neutralized drift compression of intense beam pulses: II. Analysis of experimental data of the Neutralized Drift Compression eXperiment-I (NDCX-I)

International Nuclear Information System (INIS)

Massidda, Scott; Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.; Lidia, Steven M.; Seidl, Peter; Friedman, Alex

2012-01-01

Neutralized drift compression offers an effective means for particle beam focusing and current amplification with applications to heavy ion fusion. In the Neutralized Drift Compression eXperiment-I (NDCX-I), a non-relativistic ion beam pulse is passed through an inductive bunching module that produces a longitudinal velocity modulation. Due to the applied velocity tilt, the beam pulse compresses during neutralized drift. The ion beam pulse can be compressed by a factor of more than 100; however, errors in the velocity modulation affect the compression ratio in complex ways. We have performed a study of how the longitudinal compression of a typical NDCX-I ion beam pulse is affected by the initial errors in the acquired velocity modulation. Without any voltage errors, an ideal compression is limited only by the initial energy spread of the ion beam, ΔΕ b . In the presence of large voltage errors, δU⪢ΔE b , the maximum compression ratio is found to be inversely proportional to the geometric mean of the relative error in velocity modulation and the relative intrinsic energy spread of the beam ions. Although small parts of a beam pulse can achieve high local values of compression ratio, the acquired velocity errors cause these parts to compress at different times, limiting the overall compression of the ion beam pulse.

Particle-in-cell simulation of two-dimensional electron velocity shear driven instability in relativistic domain

Energy Technology Data Exchange (ETDEWEB)

Shukla, Chandrasekhar, E-mail: chandrasekhar.shukla@gmail.com; Das, Amita, E-mail: amita@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India); Patel, Kartik [Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

2016-08-15

We carry out particle-in-cell simulations to study the instabilities associated with a 2-D sheared electron flow configuration against a neutralizing background of ions. Both weak and strong relativistic flow velocities are considered. In the weakly relativistic case, we observe the development of electromagnetic Kelvin-Helmholtz instability with similar characteristics as that predicted by the electron Magnetohydrodynamic (EMHD) model. On the contrary, in a strong relativistic case, the compressibility effects of electron fluid dominate and introduce upper hybrid electrostatic oscillations transverse to the flow which are very distinct from EMHD fluid behavior. In the nonlinear regime, both weak and strong relativistic cases lead to turbulence with broad power law spectrum.

Self-focusing relativistic electron streams in plasmas

International Nuclear Information System (INIS)

Cox, J.L. Jr.

1975-01-01

A relativistic electron stream propagating through a dense plasma induces current and charge densities which determine how the stream can self-focus. Magnetic self-focusing is possible because stream-current neutralization, although extensive, is not complete. Electric self-focusing can occur because the stream charge becomes overneutralized when the net current is smaller than a critical value. Under some circumstances, the latter process can cause the stream to focus into a series of electron bunches

An Undergraduate Exercise in the First Law of Relativistic Thermodynamics

Science.gov (United States)

Guemez, J.

2010-01-01

The isothermal compression of an ideal gas is analysed using a relativistic thermodynamics formalism based on the principle of inertia of energy (Einstein's equation) and the asynchronous formulation (Cavalleri and Salgarelli 1969 "Nuovo Cimento" 42 722-54), which is similar to the formalism developed by van Kampen (1968 "Phys. Rev." 173 295-301)…

Magnetized relativistic electron-ion plasma expansion

Science.gov (United States)

Benkhelifa, El-Amine; Djebli, Mourad

2016-03-01

The dynamics of relativistic laser-produced plasma expansion across a transverse magnetic field is investigated. Based on a one dimensional two-fluid model that includes pressure, enthalpy, and rest mass energy, the expansion is studied in the limit of λD (Debye length) ≤RL (Larmor radius) for magnetized electrons and ions. Numerical investigation conducted for a quasi-neutral plasma showed that the σ parameter describing the initial plasma magnetization, and the plasma β parameter, which is the ratio of kinetic to magnetic pressure are the key parameters governing the expansion dynamics. For σ ≪ 1, ion's front shows oscillations associated to the break-down of quasi-neutrality. This is due to the strong constraining effect and confinement of the magnetic field, which acts as a retarding medium slowing the plasma expansion.

Relativistic calculations of screening parameters and atomic radii of neutral atoms

Science.gov (United States)

Guerra, M.; Amaro, P.; Santos, J. P.; Indelicato, P.

2017-09-01

Calculations of the effective nuclear charge for elements with 1 ≤ Z ≤ 118 have been performed in a Dirac-Fock approach including all relativistic effects as well as contributions from quantum electrodynamics. Maximum charge density for every subshell of every element in the periodic table was also computed in the same framework as well as atomic radii based on the total charge density. Results were compared with the extensively cited works of Clementi et al., obtained in the 1960s with Roothan's self-consistent-field method.

Calculation of high power relativistic beams with consideration of collision effects

International Nuclear Information System (INIS)

Sveshnikov, V.M.

1986-01-01

This paper considers the numerical calculation of relativistic charged particle beams moving in axisymmetric systems in which the presence of a residual neutral gas is possible. It is essential to consider phenomena related to collisions between charged particles and neutrals. Algorithms are constructed for numerical modeling of ionization processes within the framework of the ERA program complex. Solutions of model and practical problems are presented as examples. Such problems were studied where ionization processes were considered by a more complex method requiring a greater volume of calculations but valid at lower pressures

Disposal of leached residual in heap leaching by neutralization

International Nuclear Information System (INIS)

Wang Jingmin

1993-01-01

The disposal results of leached residual with lime are described. Using the ratio of residual to lime being 100 : 1 the ideal disposal results were obtained with the effluent of the neutralized residual close to neutral

Relativistic Equations for Spin Particles: What can We Learn from Noncommutativity?

International Nuclear Information System (INIS)

Dvoeglazov, V. V.

2009-01-01

We derive relativistic equations for charged and neutral spin particles. The approach for higher-spin particles is based on generalizations of the Bargmann-Wigner formalism. Next, we study, what new physical information can give the introduction of non-commutativity. Additional non-commutative parameters can provide a suitable basis for explanation of the origin of mass.

Evidence for the Production of Neutral Mesons by Photons

CERN Document Server

Steinberger, J; Panofsky, Wolfgang Kurt Hermann

1950-01-01

In the bombardment of nuclei by 330-Mev x-rays, multiple gamma-rays are emitted. From their angular correlation it is deduced that they are emitted in pairs in the disintegration of neutral particles moving with relativistic velocities and therefore of intermediate mass. The neutral mesons are produced with cross sections similar to those for the charged mesons and with an angular distribution peaked more in the forward direction. The production cross section in hydrogen and the production cross section per nucleon in C and Be are comparable.

Injection of a relativistic electron beam into neutral hydrogen gas

International Nuclear Information System (INIS)

de Haan, P.H.; Janssen, G.C.A.M.; Hopman, H.J.; Granneman, E.H.A.

1982-01-01

The injection of a relativistic electron beam (0.8 MeV, 6 kA, 150 nsec) into hydrogen gas of 190 Pa pressure results in a plasma with density n/sub e/approx. =10 20 m -3 and temperature kT/sub e/< or approx. =kT/sub i/approx. =3.5 eV. The results of the measurements show good agreement with computations based on a model combining gas ionization and turbulent plasma heating. It is found that a quasistationary state exists in which the energy lost by the beam (about 6% of the total kinetic energy of the beam) is partly used to further ionize and dissociate the gas and for the other part is lost as line radiation

grim: A Flexible, Conservative Scheme for Relativistic Fluid Theories

Energy Technology Data Exchange (ETDEWEB)

Chandra, Mani; Gammie, Charles F. [Department of Astronomy, University of Illinois, 1110 West Green Street, Urbana, IL, 61801 (United States); Foucart, Francois, E-mail: manic@illinois.edu, E-mail: gammie@illinois.edu, E-mail: fvfoucart@lbl.gov [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

2017-03-01

Hot, diffuse, relativistic plasmas such as sub-Eddington black-hole accretion flows are expected to be collisionless, yet are commonly modeled as a fluid using ideal general relativistic magnetohydrodynamics (GRMHD). Dissipative effects such as heat conduction and viscosity can be important in a collisionless plasma and will potentially alter the dynamics and radiative properties of the flow from that in ideal fluid models; we refer to models that include these processes as Extended GRMHD. Here we describe a new conservative code, grim, that enables all of the above and additional physics to be efficiently incorporated. grim combines time evolution and primitive variable inversion needed for conservative schemes into a single step using an algorithm that only requires the residuals of the governing equations as inputs. This algorithm enables the code to be physics agnostic as well as flexibility regarding time-stepping schemes. grim runs on CPUs, as well as on GPUs, using the same code. We formulate a performance model and use it to show that our implementation runs optimally on both architectures. grim correctly captures classical GRMHD test problems as well as a new suite of linear and nonlinear test problems with anisotropic conduction and viscosity in special and general relativity. As tests and example applications, we resolve the shock substructure due to the presence of dissipation, and report on relativistic versions of the magneto-thermal instability and heat flux driven buoyancy instability, which arise due to anisotropic heat conduction, and of the firehose instability, which occurs due to anisotropic pressure (i.e., viscosity). Finally, we show an example integration of an accretion flow around a Kerr black hole, using Extended GRMHD.

Relativistic density matrix in the diagonal momentum representation. Fermi-gas

International Nuclear Information System (INIS)

Makhlin, A.N.; Sinyukov, Yu.M.

1984-01-01

The relativistically invariant theory of ideal Fermi-gas is built in the framework of the quantum field theory. The average occupation numbers and correlation functions of statistical systems are found on the equal-time surfaces of arbitrary inertial frames. The effects of anisotropy in their behaviour are pointed out. The partition function method is developed to calculate the thermodynamic quantities of Fermi-gases moving as a whole

Linear waves in two-fluid relativistic gasdynamics

International Nuclear Information System (INIS)

Gavrikov, M.B.; Solov'ev, L.S.

1988-01-01

This paper is devoted to the development of a theory of waves propagating in a two-component gaseous medium. In all cases considered the authors use only the method of two-fluid relativistic electromagnetic gasdynamics in the framework of the special relativity theory. They pay special attention to the problem of the interaction in a mixture of both neutral and charged gases when they move relative to one another. This interaction is for charged gases responsible for the appearance of ohmic resistance to an electrical current

Relativistic magnetohydrodynamics

Energy Technology Data Exchange (ETDEWEB)

Hernandez, Juan; Kovtun, Pavel [Department of Physics and Astronomy, University of Victoria,Victoria, BC, V8P 5C2 (Canada)

2017-05-02

We present the equations of relativistic hydrodynamics coupled to dynamical electromagnetic fields, including the effects of polarization, electric fields, and the derivative expansion. We enumerate the transport coefficients at leading order in derivatives, including electrical conductivities, viscosities, and thermodynamic coefficients. We find the constraints on transport coefficients due to the positivity of entropy production, and derive the corresponding Kubo formulas. For the neutral state in a magnetic field, small fluctuations include Alfvén waves, magnetosonic waves, and the dissipative modes. For the state with a non-zero dynamical charge density in a magnetic field, plasma oscillations gap out all propagating modes, except for Alfvén-like waves with a quadratic dispersion relation. We relate the transport coefficients in the “conventional” magnetohydrodynamics (formulated using Maxwell’s equations in matter) to those in the “dual” version of magnetohydrodynamics (formulated using the conserved magnetic flux).

Relativistic and non-relativistic studies of nuclear matter

NARCIS (Netherlands)

Banerjee, MK; Tjon, JA

2002-01-01

We point out that the differences between the results of the non-relativistic lowest order Brueckner theory (LOBT) and the relativistic Dirac-Brueckner analysis predominantly arise from two sources. Besides effects from a nucleon mass modification M* in nuclear medium we have in a relativistic

Relativistic gravitational potential and its relation to mass-energy

International Nuclear Information System (INIS)

Voracek, P.

1979-01-01

From the general theory of relativity a relation is deduced between the mass of a particle and the gravitational field at the position of the particle. For this purpose the fall of a particle of negligible mass in the gravitational field of a massive body is used. After establishing the relativistic potential and its relationship to the rest mass of the particle, we show, assuming conservation of mass-energy, that the difference between two potential-levels depends upon the value of the radial metric coefficient at the position of an observer. Further, it is proved that the relativistic potential is compatible with the general concept of the potential also from the standpoint of kinematics. In the third section it is shown that, although the mass-energy of a body is a function of the distance from it, this does not influence the relativistic potential of the body itself. From this conclusion it follows that the mass-energy of a particle in a gravitational field is anisotropic; isotropic is the mass only. Further, the possibility of an incidental feed-back between two masses is ruled out, and the law of the composition of the relativistic gravitational potentials is deduced. Finally, it is shown, by means of a simple model, that local inhomogeneities in the ideal fluid filling the Universe have negligible influence on the total potential in large regions. (orig.)

How to deal with relativistic heavy ion collisions

International Nuclear Information System (INIS)

Hagedorn, R.

1981-01-01

A qualitative review is given of the theoretical problems and possibilities arising when one tries to understand what happens in relativistic heavy ion collisions. The striking similarity between these and pp collisions suggests the use of techniques similar to those used five to twelve years ago in pp collisions to disentangle collective motions from thermodynamics. A very heuristic and qualitative sketch of statistical bootstrap thermodynamics concludes an idealized picture in which a relativistic heavy ion collision appears as a superposition of moving 'fireballs' with equilibrium thermodynamics in the rest frames of these fireballs. The interesting problems arise where this theoretician's picture deviates from reality: non-equilibrium, more complicated motion (shock waves, turbulence, spin) and the collision history. Only if these problems have been solved or shown to be irrelevant can we safely identify signatures of unusual states of hadronic matter as, for example, a quark-gluon plasma or density isomers. (orig.)

Simulations of space charge neutralization in a magnetized electron cooler

Energy Technology Data Exchange (ETDEWEB)

Gerity, James [Texas A-M; McIntyre, Peter M. [Texas A-M; Bruhwiler, David Leslie [RadiaSoft, Boulder; Hall, Christopher [RadiaSoft, Boulder; Moens, Vince Jan [Ecole Polytechnique, Lausanne; Park, Chong Shik [Fermilab; Stancari, Giulio [Fermilab

2017-02-02

Magnetized electron cooling at relativistic energies and Ampere scale current is essential to achieve the proposed ion luminosities in a future electron-ion collider (EIC). Neutralization of the space charge in such a cooler can significantly increase the magnetized dynamic friction and, hence, the cooling rate. The Warp framework is being used to simulate magnetized electron beam dynamics during and after the build-up of neutralizing ions, via ionization of residual gas in the cooler. The design follows previous experiments at Fermilab as a verification case. We also discuss the relevance to EIC designs.

Evaluating results from the Relativistic Heavy Ion Collider with perturbative QCD and hydrodynamics

Energy Technology Data Exchange (ETDEWEB)

Fries, R.J.; Nonaka, C.

2011-07-01

We review the basic concepts of perturbative quantum chromodynamics (QCD) and relativistic hydrodynamics, and their applications to hadron production in high energy nuclear collisions. We discuss results from the Relativistic Heavy Ion Collider (RHIC) in light of these theoretical approaches. Perturbative QCD and hydrodynamics together explain a large amount of experimental data gathered during the first decade of RHIC running, although some questions remain open. We focus primarily on practical aspects of the calculations, covering basic topics like perturbation theory, initial state nuclear effects, jet quenching models, ideal hydrodynamics, dissipative corrections, freeze-out and initial conditions. We conclude by comparing key results from RHIC to calculations.

Langevin dynamics of heavy flavors in relativistic heavy-ion collisions

CERN Document Server

Alberico, W M; De Pace, A; Molinari, A; Monteno, M; Nardi, M; Prino, F

2011-01-01

We study the stochastic dynamics of c and b quarks, produced in hard initial processes, in the hot medium created after the collision of two relativistic heavy ions. This is done through the numerical solution of the relativistic Langevin equation. The latter requires the knowledge of the friction and diffusion coefficients, whose microscopic evaluation is performed treating separately the contribution of soft and hard collisions. The evolution of the background medium is described by ideal/viscous hydrodynamics. Below the critical temperature the heavy quarks are converted into hadrons, whose semileptonic decays provide single-electron spectra to be compared with the current experimental data measured at RHIC. We focus on the nuclear modification factor R_AA and on the elliptic-flow coefficient v_2, getting, for sufficiently large p_T, a reasonable agreement.

Multiphoton ionization of many-electron atoms and highly-charged ions in intense laser fields: a relativistic time-dependent density functional theory approach

Science.gov (United States)

Tumakov, Dmitry A.; Telnov, Dmitry A.; Maltsev, Ilia A.; Plunien, Günter; Shabaev, Vladimir M.

2017-10-01

We develop an efficient numerical implementation of the relativistic time-dependent density functional theory (RTDDFT) to study multielectron highly-charged ions subject to intense linearly-polarized laser fields. The interaction with the electromagnetic field is described within the electric dipole approximation. The resulting time-dependent relativistic Kohn-Sham (RKS) equations possess an axial symmetry and are solved accurately and efficiently with the help of the time-dependent generalized pseudospectral method. As a case study, we calculate multiphoton ionization probabilities of the neutral argon atom and argon-like xenon ion. Relativistic effects are assessed by comparison of our present results with existing non-relativistic data.

Relativistic mean-field approximation with density-dependent screening meson masses in nuclear matter

International Nuclear Information System (INIS)

Sun, Baoxi; Lu, Xiaofu; Shen, Pengnian; Zhao, Enguang

2003-01-01

The Debye screening masses of the σ, ω and neutral ρ mesons and the photon are calculated in the relativistic mean-field approximation. As the density of the nucleon increases, all the screening masses of mesons increase. A different result with Brown–Rho scaling is shown, which implies a reduction in the mass of all the mesons in the nuclear matter, except the pion. Replacing the masses of the mesons with their corresponding screening masses in the Walecka-1 model, five saturation properties of the nuclear matter are fixed reasonably, and then a density-dependent relativistic mean-field model is proposed without introducing the nonlinear self-coupling terms of mesons. (author)

The impact of exposure to the thin-ideal media image on women.

Science.gov (United States)

Hawkins, Nicole; Richards, P Scott; Granley, H Mac; Stein, David M

2004-01-01

The purpose of this study was to experimentally examine the effects of exposure to the thin-ideal body image on women's affect, self-esteem, body satisfaction, eating disorder symptoms, and level of internalization of the thin-ideal. College women (N=145) were randomly exposed to photographs from popular magazines containing either thin-ideal images or neutral images. Exposure to thin-ideal magazine images increased body dissatisfaction, negative mood states, and eating disorder symptoms and decreased self-esteem, although it did not cause more internalization of the thin-ideal. Exposure to thin-ideal media images may contribute to the development of eating disorders by causing body dissatisfaction, negative moods, low self-esteem, and eating disorders symptoms among women.

Multiplicity fluctuations and correlations in limited momentum space bins in relativistic gases

International Nuclear Information System (INIS)

Hauer, Michael; Torrieri, Giorgio; Wheaton, Spencer

2009-01-01

Multiplicity fluctuations and correlations are calculated within thermalized relativistic ideal quantum gases. These are shown to be sensitive to the choice of statistical ensemble as well as to the choice of acceptance window in momentum space. It is furthermore shown that global conservation laws introduce nontrivial correlations between disconnected regions in momentum space, even in the absence of any dynamics.

Bose-Einstein condensation of a relativistic Bose gas trapped in a general external potential

International Nuclear Information System (INIS)

Su Guozhen; Chen Jincan; Chen Lixuan

2006-01-01

Bose-Einstein condensation of an ideal relativistic Bose gas trapped in a generic power-law potential is investigated. The analytical expressions for some important parameters such as the critical temperature, ground-state fraction and heat capacity are derived. The general criteria on the occurrence of Bose-Einstein condensation and the discontinuity of heat capacity at the critical temperature are obtained. The results obtained here present a unified description for the Bose-Einstein condensation of a class of ideal Bose systems so that many important conclusions in the literature are included in this paper

How do quantum numbers generally vary in the adiabatic transformation of an ideal gas?

International Nuclear Information System (INIS)

Yarman, T.; Kholmetskii, A. L.

2011-01-01

We continue to analyse the known law of adiabatic transformation for an ideal gas PV 5/3 = Constant, where P is the pressure and V is the volume, and following the approach of non-relativistic quantum mechanics which we suggested in a previous work (Yarman et al. 2010 Int. J. Phys. Sci. 5 1524). We explicitly determine the constant for the general parallelepiped geometry of a container. We also disclose how the quantum numbers associated with molecules of an ideal gas vary through an arbitrary adiabatic transformation. Physical implications of the results obtained are discussed. (physics of gases, plasmas, and electric discharges)

Nonlinear transport properties of non-ideal systems

International Nuclear Information System (INIS)

Pavlov, G A

2009-01-01

The theory of nonlinear transport is elaborated to determine the Burnett transport properties of non-ideal multi-element plasma and neutral systems. The procedure for the comparison of the phenomenological conservation equations of a continuous dense medium and the microscopic equations for dynamical variable operators is used for the definition of these properties. The Mori algorithm is developed to derive the equations of motion of dynamical value operators of a non-ideal system in the form of the generalized nonlinear Langevin equations. In consequence, the microscopic expressions of transport coefficients corresponding to second-order thermal disturbances (temperature, mass velocity, etc) have been found in the long wavelength and low frequency limits

Relativistic equations

International Nuclear Information System (INIS)

Gross, F.

1986-01-01

Relativistic equations for two and three body scattering are discussed. Particular attention is paid to relativistic three body kinetics because of recent form factor measurements of the Helium 3 - Hydrogen 3 system recently completed at Saclay and Bates and the accompanying speculation that relativistic effects are important for understanding the three nucleon system. 16 refs., 4 figs

Geometric phase for a neutral particle in rotating frames in a cosmic string spacetime

International Nuclear Information System (INIS)

Bakke, Knut; Furtado, Claudio

2009-01-01

We study of the appearance of geometric quantum phases in the dynamics of a neutral particle that possess a permanent magnetic dipole moment in rotating frames in a cosmic string spacetime. The relativistic dynamics of spin-1/2 particle in this frame is investigated and we obtain several contributions to relativistic geometric phase due rotation and topology of spacetime. We also study the geometric phase in the nonrelativistic limit. We obtain effects analogous to the Sagnac effect and Mashhoon effect in a rotating frame in the background of a cosmic string.

Point form relativistic quantum mechanics and relativistic SU(6)

Science.gov (United States)

Klink, W. H.

1993-01-01

The point form is used as a framework for formulating a relativistic quantum mechanics, with the mass operator carrying the interactions of underlying constituents. A symplectic Lie algebra of mass operators is introduced from which a relativistic harmonic oscillator mass operator is formed. Mass splittings within the degenerate harmonic oscillator levels arise from relativistically invariant spin-spin, spin-orbit, and tensor mass operators. Internal flavor (and color) symmetries are introduced which make it possible to formulate a relativistic SU(6) model of baryons (and mesons). Careful attention is paid to the permutation symmetry properties of the hadronic wave functions, which are written as polynomials in Bargmann spaces.

MARTINI: An event generator for relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Schenke, Bjoern; Gale, Charles; Jeon, Sangyong

2009-01-01

We introduce the modular algorithm for relativistic treatment of heavy ion interactions (MARTINI), a comprehensive event generator for the hard and penetrating probes in high-energy nucleus-nucleus collisions. Its main components are a time-evolution model for the soft background, PYTHIA 8.1, and the McGill-Arnold, Moore, and Yaffe (AMY) parton-evolution scheme, including radiative as well as elastic processes. This allows us to generate full event configurations in the high p T region that take into account thermal quantum chromodynamic (QCD) and quantum electrodynamic (QED) effects as well as effects of the evolving medium. We present results for the neutral pion nuclear modification factor in Au+Au collisions at the BNL Relativistic Heavy Ion Collider as a function of p T for different centralities and also as a function of the angle with respect to the reaction plane for noncentral collisions. Furthermore, we study the production of high-transverse-momentum photons, incorporating a complete set of photon-production channels.

Towards a Revised Monte Carlo Neutral Particle Surface Interaction Model

International Nuclear Information System (INIS)

Stotler, D.P.

2005-01-01

The components of the neutral- and plasma-surface interaction model used in the Monte Carlo neutral transport code DEGAS 2 are reviewed. The idealized surfaces and processes handled by that model are inadequate for accurately simulating neutral transport behavior in present day and future fusion devices. We identify some of the physical processes missing from the model, such as mixed materials and implanted hydrogen, and make some suggestions for improving the model

A unified treatment of the non-relativistic and relativistic hydrogen atom: Pt. 2

International Nuclear Information System (INIS)

Swainson, R.A.; Drake, G.W.F.

1991-01-01

This is the second in a series of three papers in which it is shown how the radial part of non-relativistic and relativistic hydrogenic bound-state calculations involving the Green functions can be presented in a unified manner. In this paper the non-relativistic Green function is examined in detail; new functional forms are presented and a clear mathematical progression is show to link these and most other known forms. A linear transformation of the four radial parts of the relativistic Green function is given which allows for the presentation of this function as a simple generalization of the non-relativistic Green function. Thus, many properties of the non-relativistic Green function are shown to have simple relativistic generalizations. In particular, new recursion relations of the radial parts of both the non-relativistic and relativistic Green functions are presented, along with new expressions for the double Laplace transforms and recursion relations between the radial matrix elements. (author)

Phase transition dynamics in ultra-relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Csernai, L.P.; Kapusta, J.I.; Kluge, G.Y.; Zabrodin, E.E.

1992-11-01

The authors investigate various problems related to the dynamics of a first-order phase transition from quark-gluon plasma to hadronic matter in ultra-relativistic heavy ion collisions. These include nucleation, growth and fusion of hadronic bubbles in either the Bjorken longitudinal hydrodynamic expansion model or the Cooper-Frye-Schonberg spherical hydrodynamic expansion model. With reasonable input parameters the conversion of one phase into the other is relatively close to the idealized adiabatic Maxwell construction, although one can choose parameters such that the conversion is strongly out of equilibrium. 10 refs., 7 figs

Relativistic astrophysics

CERN Document Server

Demianski, Marek

2013-01-01

Relativistic Astrophysics brings together important astronomical discoveries and the significant achievements, as well as the difficulties in the field of relativistic astrophysics. This book is divided into 10 chapters that tackle some aspects of the field, including the gravitational field, stellar equilibrium, black holes, and cosmology. The opening chapters introduce the theories to delineate gravitational field and the elements of relativistic thermodynamics and hydrodynamics. The succeeding chapters deal with the gravitational fields in matter; stellar equilibrium and general relativity

Studies of Ionic Photoionization Using Relativistic Random Phase Approximation and Relativistic Multichannel Quantum Defect Theory

Science.gov (United States)

Haque, Ghousia Nasreen

The absorption of electromagnetic radiation by positive ions is one of the fundamental processes of nature which occurs in every intensely hot environment. Due to the difficulties in producing sufficient densities of ions in a laboratory, there are very few measurements of ionic photoabsorption parameters. On the theoretical side, some calculations have been made of a few major photoionization parameters, but generally speaking, most of the work done so far has employed rather simple single particle models and any theoretical work which has adequately taken into account intricate atomic many-body and relativistic effects is only scanty. In the present work, several complex aspects of atomic/ionic photoabsorption parameters have been studied. Non -resonant photoionization in neon and argon isonuclear as well as isoelectronic sequences has been studied using a very sophisticated technique, namely the relativistic random phase approximation (RRPA). This technique takes into account relativistic effects as well as an important class of major many-body effects on the same footing. The present calculations confirmed that gross features of photoionization parameters calculated using simpler models were not an artifact of the simple model. Also, the present RRPA calculations on K^+ ion and neutral Ar brought out the relative importance of various many-body effects such the inter-channel coupling. Inter-channel coupling between discrete bound state photoexcitation channels from an inner atomic/ionic level and photoionization continuum channels from an outer atomic/ionic level leads to the phenomena of autoionization resonances in the photoionization process. These resonances lead to very complex effects in the atomic/ionic photoabsorption spectra. These resonances have been calculated and studied in the present work in the neon and magnesium isoelectronic sequences using the relativistic multi-channel quantum defect theory (RMQDT) within the framework of the RRPA. The

Generalised relativistic Ohm's laws, extended gauge transformations, and magnetic linking

International Nuclear Information System (INIS)

Pegoraro, F.

2015-01-01

Generalisations of the relativistic ideal Ohm's law are presented that include specific dynamical features of the current carrying particles in a plasma. Cases of interest for space and laboratory plasmas are identified where these generalisations allow for the definition of generalised electromagnetic fields that transform under a Lorentz boost in the same way as the real electromagnetic fields and that obey the same set of homogeneous Maxwell's equations

Relativistic quantum logic

International Nuclear Information System (INIS)

Mittelstaedt, P.

1983-01-01

on the basis of the well-known quantum logic and quantum probability a formal language of relativistic quantum physics is developed. This language incorporates quantum logical as well as relativistic restrictions. It is shown that relativity imposes serious restrictions on the validity regions of propositions in space-time. By an additional postulate this relativistic quantum logic can be made consistent. The results of this paper are derived exclusively within the formal quantum language; they are, however, in accordance with well-known facts of relativistic quantum physics in Hilbert space. (author)

PADÉ APPROXIMANTS FOR THE EQUATION OF STATE FOR RELATIVISTIC HYDRODYNAMICS BY KINETIC THEORY

Energy Technology Data Exchange (ETDEWEB)

Tsai, Shang-Hsi; Yang, Jaw-Yen, E-mail: shanghsi@gmail.com [Institute of Applied Mechanics, National Taiwan University, Taipei 10764, Taiwan (China)

2015-07-20

A two-point Padé approximant (TPPA) algorithm is developed for the equation of state (EOS) for relativistic hydrodynamic systems, which are described by the classical Maxwell–Boltzmann statistics and the semiclassical Fermi–Dirac statistics with complete degeneracy. The underlying rational function is determined by the ratios of the macroscopic state variables with various orders of accuracy taken at the extreme relativistic limits. The nonunique TPPAs are validated by Taub's inequality for the consistency of the kinetic theory and the special theory of relativity. The proposed TPPA is utilized in deriving the EOS of the dilute gas and in calculating the specific heat capacity, the adiabatic index function, and the isentropic sound speed of the ideal gas. Some general guidelines are provided for the application of an arbitrary accuracy requirement. The superiority of the proposed TPPA is manifested in manipulating the constituent polynomials of the approximants, which avoids the arithmetic complexity of struggling with the modified Bessel functions and the hyperbolic trigonometric functions arising from the relativistic kinetic theory.

Relativistic quantum mechanics; Mecanique quantique relativiste

Energy Technology Data Exchange (ETDEWEB)

Ollitrault, J.Y. [CEA Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique]|[Universite Pierre et Marie Curie, 75 - Paris (France)

1998-12-01

These notes form an introduction to relativistic quantum mechanics. The mathematical formalism has been reduced to the minimum in order to enable the reader to calculate elementary physical processes. The second quantification and the field theory are the logical followings of this course. The reader is expected to know analytical mechanics (Lagrangian and Hamiltonian), non-relativistic quantum mechanics and some basis of restricted relativity. The purpose of the first 3 chapters is to define the quantum mechanics framework for already known notions about rotation transformations, wave propagation and restricted theory of relativity. The next 3 chapters are devoted to the application of relativistic quantum mechanics to a particle with 0,1/5 and 1 spin value. The last chapter deals with the processes involving several particles, these processes require field theory framework to be thoroughly described. (A.C.) 2 refs.

Dissipative relativistic hydrodynamics

International Nuclear Information System (INIS)

Imshennik, V.S.; Morozov, Yu.I.

1989-01-01

Using the comoving reference frame in the general non-inertial case, the relativistic hydrodynamics equations are derived with an account for dissipative effects in the matter. From the entropy production equation, the exact from for the dissipative tensor components is obtained. As a result, the closed system of equations of dissipative relativistic hydrodynamics is obtained in the comoving reference frame as a relativistic generalization of the known Navier-Stokes equations for Lagrange coordinates. Equations of relativistic hydrodynamics with account for dissipative effects in the matter are derived using the assocoated reference system in general non-inertial case. True form of the dissipative tensor components is obtained from entropy production equation. Closed system of equations for dissipative relativistic hydrodynamics is obtained as a result in the assocoated reference system (ARS) - relativistic generalization of well-known Navier-Stokes equations for Lagrange coordinates. Equation system, obtained in this paper for ARS, may be effectively used in numerical models of explosive processes with 10 51 erg energy releases which are characteristic for flashes of supernovae, if white dwarf type compact target suggested as presupernova

Analytic properties of the relativistic Thomas-Fermi equation and the total energy of atomic ions

International Nuclear Information System (INIS)

March, N.H.; Senatore, G.

1985-06-01

The analytic properties of solutions of the relativistic Thomas-Fermi equation which tend to zero at infinity are first examined, the neutral atom solution being a member of this class. A new length is shown to enter the theory, proportional to the square root of the fine structure constant. This information is used to develop a perturbation expansion around the neutral atom solution, corresponding to positive atomic ions with finite but large radii. The limiting law relating ionic radius to the degree of ionization is thereby displayed in functional form, and solved explicitly to lowest order in the fine structure constant. To embrace this knowledge of heavy positive ions, as well as results from the one-electron Dirac equation, a proposal is then advanced as to the analytic form of the relativistic total energy E(Z,N) of an atomic ion with nuclear charge Ze and total number of electrons N. The fact that, for N>1, the nucleus is known only to bind Z+n electrons, where n is 1 or 2, indicates non-analyticity in the complex Z plane, represented by a circle of radius Z approx.= N. Such non-analyticity is also a property of the non-relativistic energy derived from the many-electron Schroedinger equation. The relativistic theory, however, must also embody a second type of non-analyticity associated with the known property for N=1 that the Dirac equation predicts electron-positron pair production when the electronic binding energy becomes equal to twice the electron rest mass energy. This corresponds to a second circle of non-analyticity in E(Z,N), and hence to a Taylor-Laurent expansion of this quantity in the atomic number Z. The relation of this expansion to the Layzer-Bahcall series is finally discussed. (author)

Box of ideal gas in free fall

Energy Technology Data Exchange (ETDEWEB)

Kothawala, Dawood, E-mail: dawood@physics.iitm.ac.in [Department of Mathematics and Statistics, University of New Brunswick, Fredericton, NB, E3B 5A3 (Canada)

2013-03-26

We study the quantum partition function of non-relativistic, ideal gas in a (non-cubical) box falling freely in arbitrary curved spacetime with center 4-velocity u{sup a}. When perturbed energy eigenvalues are properly taken into account, we find that corrections to various thermodynamic quantities include a very specific, sub-dominant term which is independent of kinematic details such as box dimensions and mass of particles. This term is characterized by the dimensionless quantity, Ξ=R{sub 0{sup ^}0{sup ^}}Λ{sup 2}, where R{sub 0{sup ^}0{sup ^}}=R{sub ab}u{sup a}u{sup b} and Λ=βℏc, and, quite intriguingly, produces Euler relation of homogeneity two between entropy and energy – a relation familiar from black hole thermodynamics.

Testing general relativity with the neutral kaon system

International Nuclear Information System (INIS)

Chardin, G.

1992-01-01

The arguments favouring gravitation as the 'Master Arrow of Time' are briefly reviewed and the possibility that CP violation observed in the neutral kaon system may be explained by a violation of the Equivalence Principle is discussed. It was attempted to demonstrate that the arguments against antigravity should be reconsidered and that the neutral kaon system, the most sensitive interferometric system at the disposal, is ideal to test the existence of antigravity. (R.P.) 33 refs

Electrical conductivity and charge carrier screening in weakly non-ideal argon plasmas

International Nuclear Information System (INIS)

Guenther, K.; Lang, S.; Radtke, R.

1983-01-01

A pulsed argon discharge as a stable source of weakly non-ideal plasmas is described in connection with the diagnostic necessities for conductivity measurements. The parameters overlap the range for stationary arcs and allow comparison with measurements in cascade arcs. The measured conductivities are explained using the binary collision model considering collisions with neutrals, excited atoms, and ions. A relation between the screening parameter and non-ideality is proposed which should be valid for all elements. (author)

Electrical conductivity and charge carrier screening in weakly non-ideal argon plasmas

Energy Technology Data Exchange (ETDEWEB)

Guenther, K; Lang, S; Radtke, R [Akademie der Wissenschaften der DDR, Jena. Zentralinstitut fuer Elektronenphysik

1983-07-14

A pulsed argon discharge as a stable source of weakly non-ideal plasmas is described in connection with the diagnostic necessities for conductivity measurements. The parameters overlap the range for stationary arcs and allow comparison with measurements in cascade arcs. The measured conductivities are explained using the binary collision model considering collisions with neutrals, excited atoms, and ions. A relation between the screening parameter and non-ideality is proposed which should be valid for all elements.

A relativistic self-consistent model for studying enhancement of space charge limited field emission due to counter-streaming ions

International Nuclear Information System (INIS)

Lin, M. C.; Lu, P. S.; Chang, P. C.; Ragan-Kelley, B.; Verboncoeur, J. P.

2014-01-01

Recently, field emission has attracted increasing attention despite the practical limitation that field emitters operate below the Child-Langmuir space charge limit. By introducing counter-streaming ion flow to neutralize the electron charge density, the space charge limited field emission (SCLFE) current can be dramatically enhanced. In this work, we have developed a relativistic self-consistent model for studying the enhancement of SCLFE by a counter-streaming ion current. The maximum enhancement is found when the ion effect is saturated, as shown analytically. The solutions in non-relativistic, intermediate, and ultra-relativistic regimes are obtained and verified with 1-D particle-in-cell simulations. This self-consistent model is general and can also serve as a benchmark or comparison for verification of simulation codes, as well as extension to higher dimensions

Radiatively driven relativistic spherical winds under relativistic radiative transfer

Science.gov (United States)

Fukue, J.

2018-05-01

We numerically investigate radiatively driven relativistic spherical winds from the central luminous object with mass M and luminosity L* under Newtonian gravity, special relativity, and relativistic radiative transfer. We solve both the relativistic radiative transfer equation and the relativistic hydrodynamical equations for spherically symmetric flows under the double-iteration processes, to obtain the intensity and velocity fields simultaneously. We found that the momentum-driven winds with scattering are quickly accelerated near the central object to reach the terminal speed. The results of numerical solutions are roughly fitted by a relation of \\dot{m}=0.7(Γ _*-1)\\tau _* β _* β _out^{-2.6}, where \\dot{m} is the mass-loss rate normalized by the critical one, Γ* the central luminosity normalized by the critical one, τ* the typical optical depth, β* the initial flow speed at the central core of radius R*, and βout the terminal speed normalized by the speed of light. This relation is close to the non-relativistic analytical solution, \\dot{m} = 2(Γ _*-1)\\tau _* β _* β _out^{-2}, which can be re-expressed as β _out^2/2 = (Γ _*-1)GM/c^2 R_*. That is, the present solution with small optical depth is similar to that of the radiatively driven free outflow. Furthermore, we found that the normalized luminosity (Eddington parameter) must be larger than unity for the relativistic spherical wind to blow off with intermediate or small optical depth, i.e. Γ _* ≳ \\sqrt{(1+β _out)^3/(1-β _out)}. We briefly investigate and discuss an isothermal wind.

A relativistic self-consistent model for studying enhancement of space charge limited emission due to counter-streaming ions

Science.gov (United States)

Lin, M. C.; Verboncoeur, J.

2016-10-01

A maximum electron current transmitted through a planar diode gap is limited by space charge of electrons dwelling across the gap region, the so called space charge limited (SCL) emission. By introducing a counter-streaming ion flow to neutralize the electron charge density, the SCL emission can be dramatically raised, so electron current transmission gets enhanced. In this work, we have developed a relativistic self-consistent model for studying the enhancement of maximum transmission by a counter-streaming ion current. The maximum enhancement is found when the ion effect is saturated, as shown analytically. The solutions in non-relativistic, intermediate, and ultra-relativistic regimes are obtained and verified with 1-D particle-in-cell simulations. This self-consistent model is general and can also serve as a comparison for verification of simulation codes, as well as extension to higher dimensions.

Handbook of relativistic quantum chemistry

International Nuclear Information System (INIS)

Liu, Wenjian

2017-01-01

This handbook focuses on the foundations of relativistic quantum mechanics and addresses a number of fundamental issues never covered before in a book. For instance: How can many-body theory be combined with quantum electrodynamics? How can quantum electrodynamics be interfaced with relativistic quantum chemistry? What is the most appropriate relativistic many-electron Hamiltonian? How can we achieve relativistic explicit correlation? How can we formulate relativistic properties? - just to name a few. Since relativistic quantum chemistry is an integral component of computational chemistry, this handbook also supplements the ''Handbook of Computational Chemistry''. Generally speaking, it aims to establish the 'big picture' of relativistic molecular quantum mechanics as the union of quantum electrodynamics and relativistic quantum chemistry. Accordingly, it provides an accessible introduction for readers new to the field, presents advanced methodologies for experts, and discusses possible future perspectives, helping readers understand when/how to apply/develop the methodologies.

Intense relativistic electron beam: generation and propagation

International Nuclear Information System (INIS)

Mittal, K.C.; Mondal, J.

2010-01-01

A general review of relativistic electron beam extracted from explosive field emission diode has been presented here. The beam current in the diode gap taking into account cathode and anode plasma expansion velocity and excluding the self magnetic field effect is directly proportional to gap voltage V 3/2 and inversely proportional to the square of the effective diode gap (d-vt). In the limit of high current, self magnetic field focusing effect comes into play and results in a critical current at which pinching will take place. When the diode current exceeds the critical current, the electron flow is in the para-potential regime. Different diode geometries such as planner, coaxial, rod-pinched, reflex triode are discussed qualitatively. When the beam is injected into a vacuum drift tube the propagation of the beam is only possible in presence of a strong axial magnetic field which prevents the beam expansion in the radial direction. If the beam is injected in the drift tube filled with dense plasma, then the redistribution of the plasma electrons effectively neutralizes the beam space charge, resulting subsequent propagation of the beam along the drift tube. The beam propagation through neutral gas is similar to the plasma filled drift tube. In this case both the neutral gas pressure and the beam current regulate the transmission of the REB. (author)

CAFE: A NEW RELATIVISTIC MHD CODE

Energy Technology Data Exchange (ETDEWEB)

Lora-Clavijo, F. D.; Cruz-Osorio, A. [Instituto de Astronomía, Universidad Nacional Autónoma de México, AP 70-264, Distrito Federal 04510, México (Mexico); Guzmán, F. S., E-mail: fdlora@astro.unam.mx, E-mail: aosorio@astro.unam.mx, E-mail: guzman@ifm.umich.mx [Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo. Edificio C-3, Cd. Universitaria, 58040 Morelia, Michoacán, México (Mexico)

2015-06-22

We introduce CAFE, a new independent code designed to solve the equations of relativistic ideal magnetohydrodynamics (RMHD) in three dimensions. We present the standard tests for an RMHD code and for the relativistic hydrodynamics regime because we have not reported them before. The tests include the one-dimensional Riemann problems related to blast waves, head-on collisions of streams, and states with transverse velocities, with and without magnetic field, which is aligned or transverse, constant or discontinuous across the initial discontinuity. Among the two-dimensional (2D) and 3D tests without magnetic field, we include the 2D Riemann problem, a one-dimensional shock tube along a diagonal, the high-speed Emery wind tunnel, the Kelvin–Helmholtz (KH) instability, a set of jets, and a 3D spherical blast wave, whereas in the presence of a magnetic field we show the magnetic rotor, the cylindrical explosion, a case of Kelvin–Helmholtz instability, and a 3D magnetic field advection loop. The code uses high-resolution shock-capturing methods, and we present the error analysis for a combination that uses the Harten, Lax, van Leer, and Einfeldt (HLLE) flux formula combined with a linear, piecewise parabolic method and fifth-order weighted essentially nonoscillatory reconstructors. We use the flux-constrained transport and the divergence cleaning methods to control the divergence-free magnetic field constraint.

Numerical magneto-hydrodynamics for relativistic nuclear collisions

Energy Technology Data Exchange (ETDEWEB)

Inghirami, Gabriele [Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Goethe-Universitaet, Institute for Theoretical Physics, Frankfurt am Main (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Forschungszentrum Juelich, John von Neumann Institute for Computing, Juelich (Germany); Del Zanna, Luca [Universita di Firenze, Dipartimento di Fisica e Astronomia, Firenze (Italy); INAF - Osservatorio Astrofisico di Arcetri, Firenze (Italy); INFN - Sezione di Firenze, Firenze (Italy); Beraudo, Andrea [INFN - Sezione di Torino, Torino (Italy); Moghaddam, Mohsen Haddadi [INFN - Sezione di Torino, Torino (Italy); Hakim Sabzevari University, Department of Physics, P. O. Box 397, Sabzevar (Iran, Islamic Republic of); Becattini, Francesco [Universita di Firenze, Dipartimento di Fisica e Astronomia, Firenze (Italy); INFN - Sezione di Firenze, Firenze (Italy); Bleicher, Marcus [Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Goethe-Universitaet, Institute for Theoretical Physics, Frankfurt am Main (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Forschungszentrum Juelich, John von Neumann Institute for Computing, Juelich (Germany)

2016-12-15

We present an improved version of the ECHO-QGP numerical code, which self-consistently includes for the first time the effects of electromagnetic fields within the framework of relativistic magneto-hydrodynamics (RMHD). We discuss results of its application in relativistic heavy-ion collisions in the limit of infinite electrical conductivity of the plasma. After reviewing the relevant covariant 3 + 1 formalisms, we illustrate the implementation of the evolution equations in the code and show the results of several tests aimed at assessing the accuracy and robustness of the implementation. After providing some estimates of the magnetic fields arising in non-central high-energy nuclear collisions, we perform full RMHD simulations of the evolution of the quark-gluon plasma in the presence of electromagnetic fields and discuss the results. In our ideal RMHD setup we find that the magnetic field developing in non-central collisions does not significantly modify the elliptic flow of the final hadrons. However, since there are uncertainties in the description of the pre-equilibrium phase and also in the properties of the medium, a more extensive survey of the possible initial conditions as well as the inclusion of dissipative effects are indeed necessary to validate this preliminary result. (orig.)

Relativistic many-body theory of atomic transitions. The relativistic equation-of-motion approach

International Nuclear Information System (INIS)

Huang, K.

1982-01-01

An equation-of-motion approach is used to develop the relativistic many-body theory of atomic transitions. The relativistic equations of motion for transition matrices are formulated with the use of techniques of quantum-field theory. To reduce the equations of motion to a tractable form which is appropriate for numerical calculations, a graphical method to resolve the complication arising from the antisymmetrization and angular-momentum coupling is employed. The relativistic equation-of-motion method allows an ab initio treatment of correlation and relativistic effects in both closed- and open-shell many-body systems. A special case of the present formulation reduces to the relativistic random-phase approximation

Relativistic many-body theory of atomic transitions: the relativistic equation-of-motion approach

International Nuclear Information System (INIS)

Huang, K.N.

1981-01-01

An equation-of-motion approach is used to develop the relativistic many-body theory of atomic transitions. The relativistic equations of motion for transition matrices are formulated using techniques of quantum field theory. To reduce the equation of motion to a tractable form which is appropriate for numerical calculations, a graphical method is employed to resolve the complication arising from the antisymmetrization and angular momentum coupling. The relativistic equation-of-motion method allows an ab initio treatment of correlation and relativistic effects in both closed- and open-shell many-body systems. A special case of the present formulation reduces to the relativistic random-phase approximation

Relativistic duality, and relativistic and radiative corrections for heavy-quark systems

International Nuclear Information System (INIS)

Durand, B.; Durand, L.

1982-01-01

We give a JWKB proof of a relativistic duality relation which relates an appropriate energy average of the physical cross section for e + e - →qq-bar bound states→hadrons to the same energy average of the perturbative cross section for e + e - →qq-bar. We show that the duality relation can be used effectively to estimate relativistic and radiative corrections for bound-quark systems to order α/sub s//sup ts2/. We also present a formula which relates the square of the ''large'' 3 S 1 Salpeter-Bethe-Schwinger wave function for zero space-time separation of the quarks to the square of the nonrelativistic Schroedinger wave function at the origin for an effective potential which reproduces the relativistic spectrum. This formula allows one to use the nonrelativistic wave functions obtained in potential models fitted to the psi and UPSILON spectra to calculate relativistic leptonic widths for qq-bar states via a relativistic version of the van Royen--Weisskopf formula

Handbook of relativistic quantum chemistry

Energy Technology Data Exchange (ETDEWEB)

Liu, Wenjian (ed.) [Peking Univ., Beijing (China). Center for Computational Science and Engineering

2017-03-01

This handbook focuses on the foundations of relativistic quantum mechanics and addresses a number of fundamental issues never covered before in a book. For instance: How can many-body theory be combined with quantum electrodynamics? How can quantum electrodynamics be interfaced with relativistic quantum chemistry? What is the most appropriate relativistic many-electron Hamiltonian? How can we achieve relativistic explicit correlation? How can we formulate relativistic properties? - just to name a few. Since relativistic quantum chemistry is an integral component of computational chemistry, this handbook also supplements the ''Handbook of Computational Chemistry''. Generally speaking, it aims to establish the 'big picture' of relativistic molecular quantum mechanics as the union of quantum electrodynamics and relativistic quantum chemistry. Accordingly, it provides an accessible introduction for readers new to the field, presents advanced methodologies for experts, and discusses possible future perspectives, helping readers understand when/how to apply/develop the methodologies.

Relativistic non-Hamiltonian mechanics

International Nuclear Information System (INIS)

Tarasov, Vasily E.

2010-01-01

Relativistic particle subjected to a general four-force is considered as a nonholonomic system. The nonholonomic constraint in four-dimensional space-time represents the relativistic invariance by the equation for four-velocity u μ u μ + c 2 = 0, where c is the speed of light in vacuum. In the general case, four-forces are non-potential, and the relativistic particle is a non-Hamiltonian system in four-dimensional pseudo-Euclidean space-time. We consider non-Hamiltonian and dissipative systems in relativistic mechanics. Covariant forms of the principle of stationary action and the Hamilton's principle for relativistic mechanics of non-Hamiltonian systems are discussed. The equivalence of these principles is considered for relativistic particles subjected to potential and non-potential forces. We note that the equations of motion which follow from the Hamilton's principle are not equivalent to the equations which follow from the variational principle of stationary action. The Hamilton's principle and the principle of stationary action are not compatible in the case of systems with nonholonomic constraint and the potential forces. The principle of stationary action for relativistic particle subjected to non-potential forces can be used if the Helmholtz conditions are satisfied. The Hamilton's principle and the principle of stationary action are equivalent only for a special class of relativistic non-Hamiltonian systems.

Recent development of relativistic molecular theory

International Nuclear Information System (INIS)

Takahito, Nakajima; Kimihiko, Hirao

2005-01-01

Today it is common knowledge that relativistic effects are important in the heavy-element chemistry. The continuing development of the relativistic molecular theory is opening up rows of the periodic table that are impossible to treat with the non-relativistic approach. The most straightforward way to treat relativistic effects on heavy-element systems is to use the four-component Dirac-Hartree-Fock approach and its electron-correlation methods based on the Dirac-Coulomb(-Breit) Hamiltonian. The Dirac-Hartree-Fock (DHF) or Dirac-Kohn-Sham (DKS) equation with the four-component spinors composed of the large- and small-components demands severe computational efforts to solve, and its applications to molecules including heavy elements have been limited to small- to medium-size systems. Recently, we have developed a very efficient algorithm for the four-component DHF and DKS approaches. As an alternative approach, several quasi-relativistic approximations have also been proposed instead of explicitly solving the four-component relativistic equation. We have developed the relativistic elimination of small components (RESC) and higher-order Douglas-Kroll (DK) Hamiltonians within the framework of the two-component quasi-relativistic approach. The developing four-component relativistic and approximate quasi-relativistic methods have been implemented into a program suite named REL4D. In this article, we will introduce the efficient relativistic molecular theories to treat heavy-atomic molecular systems accurately via the four-component relativistic and the two-component quasi-relativistic approaches. We will also show several chemical applications including heavy-element systems with our relativistic molecular approaches. (author)

Relativistic electron-beam transport in curved channels

International Nuclear Information System (INIS)

Vittitoe, C.N.; Morel, J.E.; Wright, T.P.

1982-01-01

Collisionless single particle trajectories are modeled for a single plasma channel having one section curved in a circular arc. The magnetic field is developed by superposition of straight and curved channel segments. The plasma density gives charge and beam-current neutralization. High transport efficiencies are found for turning a relativistic electron beam 90 0 under reasonable conditions of plasma current, beam energy, arc radius, channel radius, and injection distributions in velocity and in position at the channel entrance. Channel exit distributions in velocity and position are found consistent with those for a straight plasma channel of equivalent length. Such transport problems are important in any charged particle-beam application constrained by large diode-to-target distance or by requirements of maximum power deposition in a confined area

Numerical investigation of kinetic turbulence in relativistic pair plasmas - I. Turbulence statistics

Science.gov (United States)

Zhdankin, Vladimir; Uzdensky, Dmitri A.; Werner, Gregory R.; Begelman, Mitchell C.

2018-02-01

We describe results from particle-in-cell simulations of driven turbulence in collisionless, magnetized, relativistic pair plasma. This physical regime provides a simple setting for investigating the basic properties of kinetic turbulence and is relevant for high-energy astrophysical systems such as pulsar wind nebulae and astrophysical jets. In this paper, we investigate the statistics of turbulent fluctuations in simulations on lattices of up to 10243 cells and containing up to 2 × 1011 particles. Due to the absence of a cooling mechanism in our simulations, turbulent energy dissipation reduces the magnetization parameter to order unity within a few dynamical times, causing turbulent motions to become sub-relativistic. In the developed stage, our results agree with predictions from magnetohydrodynamic turbulence phenomenology at inertial-range scales, including a power-law magnetic energy spectrum with index near -5/3, scale-dependent anisotropy of fluctuations described by critical balance, lognormal distributions for particle density and internal energy density (related by a 4/3 adiabatic index, as predicted for an ultra-relativistic ideal gas), and the presence of intermittency. We also present possible signatures of a kinetic cascade by measuring power-law spectra for the magnetic, electric and density fluctuations at sub-Larmor scales.

Population of multi-quark states in exotic multiplets and thermalization in ultra-relativistic heavy ion collisions

International Nuclear Information System (INIS)

Scherer, S.; Bleicher, M.; Haussler, S.; Stoecker, H.

2008-01-01

The recent discussion about experimental evidence for pentaquark states has revitalized the interest in exotic hadrons. If such states really exist, it is natural to assume that they will be formed at the late hadronization stage of ultra-relativistic heavy ion collisions, given the success of quark recombination models in the description of hadronization. Here, we apply the qMD model to study the formation of color neutral exotic multi-quark clusters at hadronization. We search for color neutral clusters made up of up to six color charges, respectively. We thus obtain estimates for the numbers and phase space distributions of exotic hadronic states produced by clustering in heavy ion collisions, including the members of the pentaquark multiplets. We obtain particle abundances that are smaller than thermal model predictions. Moreover, the results obtained in recombination from ultra-relativistic heavy ion collisions can be compared to the estimates based on equal population of the corresponding multiplets, and to results from fully thermalized systems. We find that the distribution of exotic hadrons from recombination over large multiplets provides a sensitive signal for thermalization and decorrelation of the initial, non-equilibrium state of the collision. (author)

Relativistic Kinetic Theory

Science.gov (United States)

Vereshchagin, Gregory V.; Aksenov, Alexey G.

2017-02-01

Preface; Acknowledgements; Acronyms and definitions; Introduction; Part I. Theoretical Foundations: 1. Basic concepts; 2. Kinetic equation; 3. Averaging; 4. Conservation laws and equilibrium; 5. Relativistic BBGKY hierarchy; 6. Basic parameters in gases and plasmas; Part II. Numerical Methods: 7. The basics of computational physics; 8. Direct integration of Boltzmann equations; 9. Multidimensional hydrodynamics; Part III. Applications: 10. Wave dispersion in relativistic plasma; 11. Thermalization in relativistic plasma; 12. Kinetics of particles in strong fields; 13. Compton scattering in astrophysics and cosmology; 14. Self-gravitating systems; 15. Neutrinos, gravitational collapse and supernovae; Appendices; Bibliography; Index.

Interaction of modulated REB with plasma, formed at its transit through high-density neutral gases

International Nuclear Information System (INIS)

Kiselev, V.A.; Linnik, A.F.; Sotnikov, G.V.; Uskov, V.V.

2003-01-01

The theoretical and experimental results of investigations of the relativistic electron beam interactions with plasma, created during its penetration into neutral gas of large pressure, are presented. It is shown that by using of deeply modulated beam it is possible to avoid the depressive influence of dissipation and longitudinal nonuniform plasma density on the beam-plasma interaction efficiency

Relativistic Linear Restoring Force

Science.gov (United States)

Clark, D.; Franklin, J.; Mann, N.

2012-01-01

We consider two different forms for a relativistic version of a linear restoring force. The pair comes from taking Hooke's law to be the force appearing on the right-hand side of the relativistic expressions: d"p"/d"t" or d"p"/d["tau"]. Either formulation recovers Hooke's law in the non-relativistic limit. In addition to these two forces, we…

Relativistic decay widths of autoionization processes: The relativistic FanoADC-Stieltjes method

Energy Technology Data Exchange (ETDEWEB)

Fasshauer, Elke, E-mail: Elke.Fasshauer@uit.no [Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Tromsø–The Arctic University of Norway, N-9037 Tromsø (Norway); Theoretische Chemie, Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany); Kolorenč, Přemysl [Institute of Theoretical Physics, Faculty of Mathematics and Physics, Charles University in Prague, V Holešovičkách 2, 180 00 Prague (Czech Republic); Pernpointner, Markus [Theoretische Chemie, Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany)

2015-04-14

Electronic decay processes of ionized systems are, for example, the Auger decay or the Interatomic/ Intermolecular Coulombic Decay. In both processes, an energetically low lying vacancy is filled by an electron of an energetically higher lying orbital and a secondary electron is instantaneously emitted to the continuum. Whether or not such a process occurs depends both on the energetic accessibility and the corresponding lifetime compared to the lifetime of competing decay mechanisms. We present a realization of the non-relativistically established FanoADC-Stieltjes method for the description of autoionization decay widths including relativistic effects. This procedure, being based on the Algebraic Diagrammatic Construction (ADC), was adapted to the relativistic framework and implemented into the relativistic quantum chemistry program package Dirac. It is, in contrast to other existing relativistic atomic codes, not limited to the description of autoionization lifetimes in spherically symmetric systems, but is instead also applicable to molecules and clusters. We employ this method to the Auger processes following the Kr3d{sup −1}, Xe4d{sup −1}, and Rn5d{sup −1} ionization. Based on the results, we show a pronounced influence of mainly scalar-relativistic effects on the decay widths of autoionization processes.

Relativistic positioning systems: perspectives and prospects

Science.gov (United States)

Coll Bartolomé

2013-11-01

Relativistic positioning systems are interesting technical objects for applications around the Earth and in the Solar system. But above all else, they are basic scientific objects allowing developing relativity from its own concepts. Some past and future features of relativistic positioning sys- tems, with special attention to the developments that they suggest for an epistemic relativity (relativistic experimental approach to physics), are analyzed. This includes relativistic stereometry, which, together with relativistic positioning systems, allows to introduce the general relativistic notion of (finite) laboratory (space-time region able to perform experiments of finite size).

Electronic structure of FeTiSb using relativistic and scalar-relativistic approaches

Energy Technology Data Exchange (ETDEWEB)

Sahariya, Jagrati [Department of Physics, Manipal University Jaipur, Jaipur-303007, Rajasthan (India); Mund, H. S., E-mail: hmoond@gmail.com [Department of Physics, M. L. Sukhadia University, Udaipur-313001, Rajasthan (India)

2016-05-06

Electronic and magnetic properties of FeTiSb have been reported. The calculations are performed using spin polarized relativistic Korringa-Kohn-Rostoker scheme based on Green’s function method. Within SPR-KKR a fully relativistic and scalar-relativistic approaches have been used to investigate electronic structure of FeTiSb. Energy bands, total and partial density of states, atom specific magnetic moment along with total moment of FeTiSb alloys are presented.

Thermodynamics of an ideal generalized gas: I. Thermodynamic laws.

Science.gov (United States)

Lavenda, B H

2005-11-01

The equations of state for an ideal relativistic, or generalized, gas, like an ideal quantum gas, are expressed in terms of power laws of the temperature. In contrast to an ideal classical gas, the internal energy is a function of volume at constant temperature, implying that the ideal generalized gas will show either attractive or repulsive interactions. This is a necessary condition in order that the third law be obeyed and for matter to have an electromagnetic origin. The transition from an ideal generalized to a classical gas occurs when the two independent solutions of the subsidiary equation to Lagrange's equation coalesce. The equation of state relating the pressure to the internal energy encompasses the full range of cosmological scenarios, from the radiation to the matter dominated universes and finally to the vacuum energy, enabling the coefficient of proportionality, analogous to the Grüeisen ratio, to be interpreted in terms of the degrees of freedom related to the temperature exponents of the internal energy and the absolute temperature expressed in terms of a power of the empirical temperature. The limit where these exponents merge is shown to be the ideal classical gas limit. A corollary to Carnot's theorem is proved, asserting that the ratio of the work done over a cycle to the heat absorbed to increase the temperature at constant volume is the same for all bodies at the same volume. As power means, the energy and entropy are incomparable, and a new adiabatic potential is introduced by showing that the volume raised to a characteristic exponent is also the integrating factor for the quantity of heat so that the second law can be based on the property that power means are monotonically increasing functions of their order. The vanishing of the chemical potential in extensive systems implies that energy cannot be transported without matter and is equivalent to the condition that Clapeyron's equation be satisfied.

Ion beam enhancement in magnetically insulated ion diodes for high-intensity pulsed ion beam generation in non-relativistic mode

Energy Technology Data Exchange (ETDEWEB)

Zhu, X. P. [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Zhang, Z. C.; Lei, M. K., E-mail: surfeng@dlut.edu.cn [Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Pushkarev, A. I. [Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Laboratory of Beam and Plasma Technology, High Technologies Physics Institute, Tomsk Polytechnic University, 30, Lenin Ave, 634050 Tomsk (Russian Federation)

2016-01-15

High-intensity pulsed ion beam (HIPIB) with ion current density above Child-Langmuir limit is achieved by extracting ion beam from anode plasma of ion diodes with suppressing electron flow under magnetic field insulation. It was theoretically estimated that with increasing the magnetic field, a maximal value of ion current density may reach nearly 3 times that of Child-Langmuir limit in a non-relativistic mode and close to 6 times in a highly relativistic mode. In this study, the behavior of ion beam enhancement by magnetic insulation is systematically investigated in three types of magnetically insulated ion diodes (MIDs) with passive anode, taking into account the anode plasma generation process on the anode surface. A maximal enhancement factor higher than 6 over the Child-Langmuir limit can be obtained in the non-relativistic mode with accelerating voltage of 200–300 kV. The MIDs differ in two anode plasma formation mechanisms, i.e., surface flashover of a dielectric coating on the anode and explosive emission of electrons from the anode, as well as in two insulation modes of external-magnetic field and self-magnetic field with either non-closed or closed drift of electrons in the anode-cathode (A-K) gap, respectively. Combined with ion current density measurement, energy density characterization is employed to resolve the spatial distribution of energy density before focusing for exploring the ion beam generation process. Consistent results are obtained on three types of MIDs concerning control of neutralizing electron flows for the space charge of ions where the high ion beam enhancement is determined by effective electron neutralization in the A-K gap, while the HIPIB composition of different ion species downstream from the diode may be considerably affected by the ion beam neutralization during propagation.

Relativistic entanglement from relativistic quantum mechanics in the rest-frame instant form of dynamics

International Nuclear Information System (INIS)

Lusanna, Luca

2011-01-01

After a review of the problems induced by the Lorentz signature of Minkowski space-time, like the need of a clock synchronization convention for the definition of 3-space and the complexity of the notion of relativistic center of mass, there is the introduction of a new formulation of relativistic quantum mechanics compatible with the theory of relativistic bound states. In it the zeroth postulate of non-relativistic quantum mechanics is not valid and the physics is described in the rest frame by a Hilbert space containing only relative variables. The non-locality of the Poincare' generators imply a kinematical non-locality and non-separability influencing the theory of relativistic entanglement and not connected with the standard quantum non-locality.

Relativistic Descriptions of Few-Body Systems

International Nuclear Information System (INIS)

Karmanov, V. A.

2011-01-01

A brief review of relativistic effects in few-body systems, of theoretical approaches, recent developments and applications is given. Manifestations of relativistic effects in the binding energies, in the electromagnetic form factors and in three-body observables are demonstrated. The three-body forces of relativistic origin are also discussed. We conclude that relativistic effects in nuclei can be important in spite of small binding energy. At high momenta they clearly manifest themselves and are necessary to describe the deuteron e.m. form factors. At the same time, there is still a discrepancy in three-body observables which might be a result of less clarity in understanding the corresponding relativistic effects, the relativistic NN kernel and the three-body forces. Relativistic few-body physics remains to be a field of very intensive and fruitful researches. (author)

A combined photoelectron spectroscopy and relativistic ab initio studies of the electronic structures of UFO and UFO-

Science.gov (United States)

Roy, Soumendra K.; Jian, Tian; Lopez, Gary V.; Li, Wei-Li; Su, Jing; Bross, David H.; Peterson, Kirk A.; Wang, Lai-Sheng; Li, Jun

2016-02-01

The observation of the gaseous UFO- anion is reported, which is investigated using photoelectron spectroscopy and relativisitic ab initio calculations. Two strong photoelectron bands are observed at low binding energies due to electron detachment from the U-7sσ orbital. Numerous weak detachment bands are also observed due to the strongly correlated U-5f electrons. The electron affinity of UFO is measured to be 1.27(3) eV. High-level relativistic quantum chemical calculations have been carried out on the ground state and many low-lying excited states of UFO to help interpret the photoelectron spectra and understand the electronic structure of UFO. The ground state of UFO- is linear with an O-U-F structure and a 3H4 spectral term derived from a U 7sσ25fφ15fδ1 electron configuration, whereas the ground state of neutral UFO has a 4H7/2 spectral term with a U 7sσ15fφ15fδ1 electron configuration. Strong electron correlation effects are found in both the anionic and neutral electronic configurations. In the UFO neutral, a high density of electronic states with strong configuration mixing is observed in most of the scalar relativistic and spin-orbit coupled states. The strong electron correlation, state mixing, and spin-orbit coupling of the electronic states make the excited states of UFO very challenging for accurate quantum chemical calculations.

A combined photoelectron spectroscopy and relativistic ab initio studies of the electronic structures of UFO and UFO(-).

Science.gov (United States)

Roy, Soumendra K; Jian, Tian; Lopez, Gary V; Li, Wei-Li; Su, Jing; Bross, David H; Peterson, Kirk A; Wang, Lai-Sheng; Li, Jun

2016-02-28

The observation of the gaseous UFO(-) anion is reported, which is investigated using photoelectron spectroscopy and relativisitic ab initio calculations. Two strong photoelectron bands are observed at low binding energies due to electron detachment from the U-7sσ orbital. Numerous weak detachment bands are also observed due to the strongly correlated U-5f electrons. The electron affinity of UFO is measured to be 1.27(3) eV. High-level relativistic quantum chemical calculations have been carried out on the ground state and many low-lying excited states of UFO to help interpret the photoelectron spectra and understand the electronic structure of UFO. The ground state of UFO(-) is linear with an O-U-F structure and a (3)H4 spectral term derived from a U 7sσ(2)5fφ(1)5fδ(1) electron configuration, whereas the ground state of neutral UFO has a (4)H(7/2) spectral term with a U 7sσ(1)5fφ(1)5fδ(1) electron configuration. Strong electron correlation effects are found in both the anionic and neutral electronic configurations. In the UFO neutral, a high density of electronic states with strong configuration mixing is observed in most of the scalar relativistic and spin-orbit coupled states. The strong electron correlation, state mixing, and spin-orbit coupling of the electronic states make the excited states of UFO very challenging for accurate quantum chemical calculations.

Sensitivity of relativistic impulse approximation proton-nucleus elastic scattering calculations on relativistic mean-field parameterizations

International Nuclear Information System (INIS)

Hojsik, M.; Gmuca, S.

1998-01-01

Relativistic microscopic calculations are presented for proton elastic scattering from 40 Ca at 500 MeV. The underlying target densities are calculated within the framework of the relativistic mean-field theory with several parameter sets commonly in use. The self consistency of the scalar and vector densities (and thus to relativistic mean-field parameters) is investigated. Recently, the relativistic impulse approximation (RIA) has been widely and repeatedly used for the calculations of proton-nucleus scattering at intermediate energies. These calculations have exhibited significant improvements over the nonrelativistic approaches. The relativistic impulse approximation calculations. in particular, provide a dramatically better description of the spin observables, namely the analyzing power, A y , and the spin-rotation function, Q, at least for energies higher than 400 MeV. In the relativistic impulse approximation, the Dirac optical potential is obtained by folding of the local Lorentz-invariant amplitudes with the corresponding nuclear densities. For the spin zero targets the scalar and vector terms give the dominant contributions. Thus the scalar and vector nuclear densities (both, proton and neutron ones) play the dominant role in the relativistic impulse approximation. While the proton vector densities can be obtained by unfolding from the empirically known charge densities, all other densities used rely to a great extent on theoretical models. The various recipes are used to construct the neutron vector densities and the scalar densities for both, neutrons and protons. In this paper we will study the sensitivity of the relativistic impulse approximation results on the various sets of relativistic mean-field parameters currently in use

The relativistic virial theorem

International Nuclear Information System (INIS)

Lucha, W.; Schoeberl, F.F.

1989-11-01

The relativistic generalization of the quantum-mechanical virial theorem is derived and used to clarify the connection between the nonrelativistic and (semi-)relativistic treatment of bound states. 12 refs. (Authors)

Positron kinetics in an idealized PET environment

Science.gov (United States)

Robson, R. E.; Brunger, M. J.; Buckman, S. J.; Garcia, G.; Petrović, Z. Lj.; White, R. D.

2015-08-01

The kinetic theory of non-relativistic positrons in an idealized positron emission tomography PET environment is developed by solving the Boltzmann equation, allowing for coherent and incoherent elastic, inelastic, ionizing and annihilating collisions through positronium formation. An analytic expression is obtained for the positronium formation rate, as a function of distance from a spherical source, in terms of the solutions of the general kinetic eigenvalue problem. Numerical estimates of the positron range - a fundamental limitation on the accuracy of PET, are given for positrons in a model of liquid water, a surrogate for human tissue. Comparisons are made with the ‘gas-phase’ assumption used in current models in which coherent scattering is suppressed. Our results show that this assumption leads to an error of the order of a factor of approximately 2, emphasizing the need to accurately account for the structure of the medium in PET simulations.

Inductive and electrostatic acceleration in relativistic jet-plasma interactions.

Science.gov (United States)

Ng, Johnny S T; Noble, Robert J

2006-03-24

We report on the observation of rapid particle acceleration in numerical simulations of relativistic jet-plasma interactions and discuss the underlying mechanisms. The dynamics of a charge-neutral, narrow, electron-positron jet propagating through an unmagnetized electron-ion plasma was investigated using a three-dimensional, electromagnetic, particle-in-cell computer code. The interaction excited magnetic filamentation as well as electrostatic plasma instabilities. In some cases, the longitudinal electric fields generated inductively and electrostatically reached the cold plasma-wave-breaking limit, and the longitudinal momentum of about half the positrons increased by 50% with a maximum gain exceeding a factor of 2 during the simulation period. Particle acceleration via these mechanisms occurred when the criteria for Weibel instability were satisfied.

Ion temperature effect on the propagation of ion acoustic solitary waves in a relativistic magnetoplasma

International Nuclear Information System (INIS)

Salahuddin, M.

1990-01-01

Using the reductive perturbation technique the Korteweg-de Vries (KdV) equation is derived for ion acoustic waves, in the presence of weak relativistic effects and warm ions, in a magnetized plasma. The influence of non ideal effects on the amplitude and width of the ion acoustic solitary waves is also discussed. The results are depicted in the figures. It is shown that the simultaneous presence of ion streaming and magnetic field stops the tendency of soliton breaking. (author)

Relativistic electron beam - plasma interaction with intense self-fields

International Nuclear Information System (INIS)

Davidson, R.C.

1984-01-01

The major interest in the equilibrium, stability and radiation properties of relativistic electron beams and in beam-plasma interactions originates from several diverse research areas. It is well known that a many-body collection of charged particles in which there is not overall charge neutrality and/or current neutrality can be characterized by intense self-electric fields and/or self-magnetic fields. Moreover, the intense equilibrium self-fields associated with the lack of charge neutrality and/or current neutrality can have a large effect on particle trajectories and on detailed equilibrium and stability behavior. The main emphasis in Sections 9.1.2-9.1.5 of this chapter is placed on investigations of the important influence of self-fields on the equilibrium and stability properties of magnetically confined electron beam-plasma systems. Atomic processes and discrete particle interactions (binary collisions) are omitted from the analysis, and collective processes are assumed to dominate on the time and length scales of interest. Moreover, both macroscopic (Section 9.1.2) and kinetic (Sections 9.1.3-9.1.5) theoretical models are developed and used to investigate equilibrium and stability properties in straight cylindrical geometry. Several of the classical waves and instabilities characteristic of nonneutral plasmas and beam-plasma systems are analyzed in Sections 9.1.2-9.1.5, including stable surface oscillation on a nonneutral electron beam, the ion resonance instability, the diocotron instability, two-stream instabilities between beam electrons and plasma electrons and between beam electrons and plasma ions, the filamentation instability, the modified two-stream instability, etc

Karakter Ideal Konselor Multibudaya Berdasarkan Nilai Luhur Semar

Directory of Open Access Journals (Sweden)

Nora Yuniar Setyaputri

2017-06-01

Full Text Available Abstract: Nowadays a lot of counselor labeling their counselee which caused counselor’s lack of multicultural insights. Labeling may have a poor impact on the counselor’s decision in selecting counseling intervention strategies. The multicultural insights of counselors must be enhanced by building an ideal character in themselves. This ideal character is concerned with the understanding and behavior of counselors to respond the condition of heterogeneous counselees and how high the curiosity, interest and motivation of counselors to constantly add multicultural insights that they have. The noble values contained within Semar can be attributed to how the ideal character of multicultural counselors. This study aims to explain the ideal character of multicultural counselor taken from the noble value of Semar as well as linking the character with multicultural competence of counselor. This research uses qualitative approach of library research type. The ideal characteristics of multicultural counselors that can be formulated include: (1 religious; (2 neutral; (3 tolerance; (4 sincere; (5 discipline; (6 social care; (7 friendly; (8 fair; (9 honest; (10 supple; (11 democratic; and (12 curiosity. Abstrak: Saat ini banyak konselor yang melakukan pelabelan karena kurangnya wawasan multibudaya konselor tersebut. Pelabelan yang dilakukan oleh konselor ini dapat berdampak kurang baik terhadap pemilihan strategi intervensi konselor terhadap konselinya. Wawasan multibudaya yang dimiliki konselor harus ditingkatkan dengan cara membangun karakter yang ideal pada diri mereka. Karakter ideal ini berkaitan dengan pemahaman dan perilaku konselor untuk menyikapi kondisi konseli yang heterogen serta seberapa tinggi rasa ingin tahu, minat maupun motivasi konselor untuk senantiasa menambah wawasan multibudaya yang mereka miliki. Nilai-nilai luhur yang terdapat di dalam diri Semar dapat dikaitkan dengan bagaimana karakter ideal konselor multibudaya. Penelitian ini

Contraint's theory and relativistic dynamics

International Nuclear Information System (INIS)

Longhi, G.; Lusanna, L.

1987-01-01

The purpose of this Workshop was to examine the current situation of relativistic dynamics. In particular, Dirac-Bergmann's theory of constraints, which lies at the heart of gauge theories, general relativity, relativistic mechanics and string theories, was chosen as the unifying theoretical framework best suited to investigate such a field. The papers discussed were on general relativity; relativistic mechanics; particle physics and mathematical physics. Also discussed were the problems of classical and quantum level, namely the identification of the classical observables of constrained systems, the equivalence of the nonequivalence of the various ways to quantize such systems; the problem of the anomalies; the best geometrical approach to the theory of constraints; the possibility of unifying all the treatments of relativistic mechanics. This book compiles the papers presented at proceedings of relativistic dynamics and constraints theory

Multiwavelength Observations of Relativistic Jets from General Relativistic Magnetohydrodynamic Simulations

Directory of Open Access Journals (Sweden)

Richard Anantua

2018-03-01

Full Text Available This work summarizes a program intended to unify three burgeoning branches of the high-energy astrophysics of relativistic jets: general relativistic magnetohydrodynamic (GRMHD simulations of ever-increasing dynamical range, the microphysical theory of particle acceleration under relativistic conditions, and multiwavelength observations resolving ever-decreasing spatiotemporal scales. The process, which involves converting simulation output into time series of images and polarization maps that can be directly compared to observations, is performed by (1 self-consistently prescribing models for emission, absorption, and particle acceleration and (2 performing time-dependent polarized radiative transfer. M87 serves as an exemplary prototype for this investigation due to its prominent and well-studied jet and the imminent prospect of learning much more from Event Horizon Telescope (EHT observations this year. Synthetic observations can be directly compared with real observations for observational signatures such as jet instabilities, collimation, relativistic beaming, and polarization. The simplest models described adopt the standard equipartition hypothesis; other models calculate emission by relating it to current density or shear. These models are intended for application to the radio jet instead of the higher frequency emission, the disk and the wind, which will be subjects of future investigations.

Collective ion acceleration by relativistic electron beams in plasmas

International Nuclear Information System (INIS)

Galvez, M.; Gisler, G.

1991-01-01

A two-dimensional fully electromagnetic particle-in-cell code is used to simulate the interaction of a relativistic electron beam injected into a finite-size background neutral plasma. The simulations show that the background electrons are pushed away from the beam path, forming a neutralizing ion channel. Soon after the beam head leaves the plasma, a virtual cathode forms which travels away with the beam. However, at later times a second, quasi-stationary, virtual cathode forms. Its position and strength depends critically on the parameters of the system which critically determines the efficiency of the ion acceleration process. The background ions trapped in the electrostatic well of the virtual cathode are accelerated and at later times, the ions as well as the virtual cathode drift away from the plasma region. The surfing of the ions in the electrostatic well produces an ion population with energies several times the initial electron beam energy. It is found that optimum ion acceleration occurs when the beam-to-plasma density ratio is near unity. When the plasma is dense, the beam is a weak perturbation and accelerates few ions, while when the plasma is tenuous, the beam is not effectively neutralized, and a virtual cathode occurs right at the injection plane. The simulations also show that, at the virtual cathode position, the electron beam is pinched producing a self-focusing phenomena

Plasma relativistic microwave electronics

International Nuclear Information System (INIS)

Kuzelev, M.V.; Loza, O.T.; Rukhadze, A.A.; Strelkov, P.S.; Shkvarunets, A.G.

2001-01-01

One formulated the principles of plasma relativistic microwave electronics based on the induced Cherenkov radiation of electromagnetic waves at interaction of a relativistic electron beam with plasma. One developed the theory of plasma relativistic generators and accelerators of microwave radiation, designed and studied the prototypes of such devices. One studied theoretically the mechanisms of radiation, calculated the efficiencies and the frequency spectra of plasma relativistic microwave generators and accelerators. The theory findings are proved by the experiment: intensity of the designed sources of microwave radiation is equal to 500 μW, the frequency of microwave radiation is increased by 7 times (from 4 up to 28 GHz), the width of radiation frequency band may vary from several up to 100%. The designed sources of microwave radiation are no else compared in the electronics [ru

Relativistic Quantum Mechanics

International Nuclear Information System (INIS)

Antoine, J-P

2004-01-01

The aim of relativistic quantum mechanics is to describe the finer details of the structure of atoms and molecules, where relativistic effects become nonnegligible. It is a sort of intermediate realm, between the familiar nonrelativistic quantum mechanics and fully relativistic quantum field theory, and thus it lacks the simplicity and elegance of both. Yet it is a necessary tool, mostly for quantum chemists. Pilkuhn's book offers to this audience an up-to-date survey of these methods, which is quite welcome since most previous textbooks are at least ten years old. The point of view of the author is to start immediately in the relativistic domain, following the lead of Maxwell's equations rather than classical mechanics, and thus to treat the nonrelativistic version as an approximation. Thus Chapter 1 takes off from Maxwell's equations (in the noncovariant Coulomb gauge) and gradually derives the basic aspects of Quantum Mechanics in a rather pedestrian way (states and observables, Hilbert space, operators, quantum measurement, scattering,. Chapter 2 starts with the Lorentz transformations, then continues with the Pauli spin equation and the Dirac equation and some of their applications (notably the hydrogen atom). Chapter 3 is entitled 'Quantum fields and particles', but falls short of treating quantum field theory properly: only creation/annihilation operators are considered, for a particle in a box. The emphasis is on two-electron states (the Pauli principle, the Foldy--Wouthuysen elimination of small components of Dirac spinors, Breit projection operators. Chapter 4 is devoted to scattering theory and the description of relativistic bound states. Chapter 5, finally, covers hyperfine interactions and radiative corrections. As we said above, relativistic quantum mechanics is by nature limited in scope and rather inelegant and Pilkuhn's book is no exception. The notation is often heavy (mostly noncovariant) and the mathematical level rather low. The central topic

Relativistic particle in a box

OpenAIRE

Alberto, P.; Fiolhais, Carlos; Gil, Victor

1996-01-01

The problem of a relativistic spin 1/2 particle confined to a one-dimensional box is solved in a way that resembles closely the solution of the well known quantum-mechanical textbook problem of a non-relativistic particle in a box. The energy levels and probability density are computed and compared with the non-relativistic case

Search for non-relativistic magnetic monopoles with IceCube

International Nuclear Information System (INIS)

Aartsen, M.G.; Hill, G.C.; Robertson, S.; Whelan, B.J.; Abbasi, R.; Ahlers, M.; Arguelles, C.; Baker, M.; BenZvi, S.; Chirkin, D.; Day, M.; Desiati, P.; Diaz-Velez, J.C.; Eisch, J.; Fadiran, O.; Feintzeig, J.; Gladstone, L.; Halzen, F.; Hoshina, K.; Jacobsen, J.; Jero, K.; Karle, A.; Kauer, M.; Kelley, J.L.; Kopper, C.; Krasberg, M.; Kurahashi, N.; Landsman, H.; Maruyama, R.; McNally, F.; Merck, M.; Morse, R.; Riedel, B.; Rodrigues, J.P.; Santander, M.; Tobin, M.N.; Toscano, S.; Van Santen, J.; Weaver, C.; Wellons, M.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Ackermann, M.; Benabderrahmane, M.L.; Berghaus, P.; Bernardini, E.; Bretz, H.P.; Cruz Silva, A.H.; Gluesenkamp, T.; Jacobi, E.; Kaminsky, B.; Karg, T.; Middell, E.; Mohrmann, L.; Nahnhauer, R.; Schoenwald, A.; Shanidze, R.; Spiering, C.; Stoessl, A.; Yanez, J.P.; Adams, J.; Brown, A.M.; Hickford, S.; Macias, O.; Aguilar, J.A.; Christov, A.; Montaruli, T.; Rameez, M.; Vallecorsa, S.; Altmann, D.; Classen, L.; Gora, D.; Kappes, A.; Tselengidou, M.; Arlen, T.C.; De Andre, J.P.A.M.; DeYoung, T.; Dunkman, M.; Eagan, R.; Groh, J.C.; Huang, F.; Quinnan, M.; Smith, M.W.E.; Stanisha, N.A.; Tesic, G.; Auffenberg, J.; Bissok, M.; Blumenthal, J.; Gretskov, P.; Haack, C.; Hallen, P.; Heinen, D.; Jagielski, K.; Kriesten, A.; Krings, K.; Leuermann, M.; Paul, L.; Raedel, L.; Reimann, R.; Schoenen, S.; Schukraft, A.; Vehring, M.; Wallraff, M.; Wiebusch, C.H.; Zierke, S.; Bai, X.; Evenson, P.A.; Gaisser, T.K.; Gonzalez, J.G.; Hussain, S.; Kuwabara, T.; Ruzybayev, B.; Seckel, D.; Stanev, T.; Tamburro, A.; Tilav, S.; Barwick, S.W.; Yodh, G.; Baum, V.; Eberhardt, B.; Koepke, L.; Kroll, G.; Luenemann, J.; Sander, H.G.; Schatto, K.; Wiebe, K.; Bay, R.; Filimonov, K.; Price, P.B.; Woschnagg, K.; Beatty, J.J.; Becker Tjus, J.; Eichmann, B.; Fedynitch, A.; Saba, S.M.; Schoeneberg, S.; Unger, E.; Becker, K.H.; Bindig, D.; Fischer-Wasels, T.; Helbing, K.; Hoffmann, R.; Klaes, J.; Kopper, S.; Naumann, U.; Obertacke, A.; Omairat, A.; Posselt, J.; Soldin, D.; Tepe, A.; Berley, D.; Blaufuss, E.; Christy, B.; Goodman, J.A.; Hellauer, R.; Hoffman, K.D.; Huelsnitz, W.; Meagher, K.; Olivas, A.; Redl, P.; Richman, M.; Schmidt, T.; Sullivan, G.W.; Wissing, H.; Bernhard, A.; Coenders, S.; Gross, A.; Leute, J.; Resconi, E.; Schulz, O.; Sestayo, Y.; Besson, D.Z.; Binder, G.; Gerhardt, L.; Ha, C.; Klein, S.R.; Miarecki, S.; Boersma, D.J.; Botner, O.; Euler, S.; Hallgren, A.; Perez de los Heros, C.; Stroem, R.; Taavola, H.; Bohm, C.; Danninger, M.; Finley, C.; Flis, S.; Hulth, P.O.; Hultqvist, K.; Walck, C.; Wolf, M.; Zoll, M.; Bose, D.; Rott, C.

2014-01-01

The IceCube Neutrino Observatory is a large Cherenkov detector instrumenting 1 km 3 of Antarctic ice. The detector can be used to search for signatures of particle physics beyond the Standard Model. Here, we describe the search for non-relativistic, magnetic monopoles as remnants of the Grand Unified Theory (GUT) era shortly after the Big Bang. Depending on the underlying gauge group these monopoles may catalyze the decay of nucleons via the Rubakov-Callan effect with a cross section suggested to be in the range of 10 -27 to 10 -21 cm 2 . In IceCube, the Cherenkov light from nucleon decays along the monopole trajectory would produce a characteristic hit pattern. This paper presents the results of an analysis of first data taken from May 2011 until May 2012 with a dedicated slow particle trigger for DeepCore, a subdetector of IceCube. A second analysis provides better sensitivity for the brightest non-relativistic monopoles using data taken from May 2009 until May 2010. In both analyses no monopole signal was observed. For catalysis cross sections of 10 -22 (10 -24 ) cm 2 the flux of non-relativistic GUT monopoles is constrained up to a level of Φ 90 ≤ 10 -18 (10 -17 ) cm -2 s -1 sr -1 at a 90 % confidence level, which is three orders of magnitude below the Parker bound. The limits assume a dominant decay of the proton into a positron and a neutral pion. These results improve the current best experimental limits by one to two orders of magnitude, for a wide range of assumed speeds and catalysis cross sections. (orig.)

Single exposure to disclaimers on airbrushed thin ideal images increases negative thought accessibility.

Science.gov (United States)

Selimbegović, Leila; Chatard, Armand

2015-01-01

Disclaimers on airbrushed thin ideal images can attract attention to the thin ideal standard promoted by the advertisements, which can be damaging rather than helpful. In this study, 48 female college students were exposed to a thin ideal image including a disclaimer, a neutral sentence, or nothing. Two weeks and two months after this, they were again exposed to the same image but with no accompanying text in any of the conditions. Negative thought accessibility was assessed three times, after each exposure to the thin-ideal image, using reaction time measures. Participants randomly assigned to the disclaimer condition systematically showed greater accessibility of negative thoughts than those in the other two conditions, irrespective of the time of measurement. These results suggest that disclaimers on airbrushed images may have some counter-productive effects by accentuating the problems that they precisely aim to address. Copyright © 2014 Elsevier Ltd. All rights reserved.

Relativistic hydrodynamics

CERN Document Server

Luciano, Rezzolla

2013-01-01

Relativistic hydrodynamics is a very successful theoretical framework to describe the dynamics of matter from scales as small as those of colliding elementary particles, up to the largest scales in the universe. This book provides an up-to-date, lively, and approachable introduction to the mathematical formalism, numerical techniques, and applications of relativistic hydrodynamics. The topic is typically covered either by very formal or by very phenomenological books, but is instead presented here in a form that will be appreciated both by students and researchers in the field. The topics covered in the book are the results of work carried out over the last 40 years, which can be found in rather technical research articles with dissimilar notations and styles. The book is not just a collection of scattered information, but a well-organized description of relativistic hydrodynamics, from the basic principles of statistical kinetic theory, down to the technical aspects of numerical methods devised for the solut...

Study of quantum spin correlations of relativistic electron pairs - Testing nonlocality of relativistic quantum mechanics

International Nuclear Information System (INIS)

Bodek, K.; Rozpędzik, D.; Zejma, J.; Caban, P.; Rembieliński, J.; Włodarczyk, M.; Ciborowski, J.; Enders, J.; Köhler, A.; Kozela, A.

2013-01-01

The Polish-German project QUEST aims at studying relativistic quantum spin correlations of the Einstein-Rosen-Podolsky-Bohm type, through measurement of the correlation function and the corresponding probabilities for relativistic electron pairs. The results will be compared to theoretical predictions obtained by us within the framework of relativistic quantum mechanics, based on assumptions regarding the form of the relativistic spin operator. Agreement or divergence will be interpreted in the context of non-uniqueness of the relativistic spin operator in quantum mechanics as well as dependence of the correlation function on the choice of observables representing the spin. Pairs of correlated electrons will originate from the Mo/ller scattering of polarized 15 MeV electrons provided by the superconducting Darmstadt electron linear accelerator S-DALINAC, TU Darmstadt, incident on a Be target. Spin projections will be determined using the Mott polarimetry technique. Measurements (starting 2013) are planned for longitudinal and transverse beam polarizations and different orientations of the beam polarization vector w.r.t. the Mo/ller scattering plane. This is the first project to study relativistic spin correlations for particles with mass

Relativistic viscoelastic fluid mechanics

International Nuclear Information System (INIS)

Fukuma, Masafumi; Sakatani, Yuho

2011-01-01

A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

Relativistic viscoelastic fluid mechanics.

Science.gov (United States)

Fukuma, Masafumi; Sakatani, Yuho

2011-08-01

A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

Relativistic electron mirrors from high intensity laser nanofoil interactions

International Nuclear Information System (INIS)

Kiefer, Daniel

2012-01-01

The reflection of a laser pulse from a mirror moving close to the speed of light could in principle create an X-ray pulse with unprecedented high brightness owing to the increase in photon energy and accompanying temporal compression by a factor of 4γ 2 , where γ is the Lorentz factor of the mirror. While this scheme is theoretically intriguingly simple and was first discussed by A. Einstein more than a century ago, the generation of a relativistic structure which acts as a mirror is demanding in many different aspects. Recently, the interaction of a high intensity laser pulse with a nanometer thin foil has raised great interest as it promises the creation of a dense, attosecond short, relativistic electron bunch capable of forming a mirror structure that scatters counter-propagating light coherently and shifts its frequency to higher photon energies. However, so far, this novel concept has been discussed only in theoretical studies using highly idealized interaction parameters. This thesis investigates the generation of a relativistic electron mirror from a nanometer foil with current state-of-the-art high intensity laser pulses and demonstrates for the first time the reflection from those structures in an experiment. To achieve this result, the electron acceleration from high intensity laser nanometer foil interactions was studied in a series of experiments using three inherently different high power laser systems and free-standing foils as thin as 3nm. A drastic increase in the electron energies was observed when reducing the target thickness from the micrometer to the nanometer scale. Quasi-monoenergetic electron beams were measured for the first time from ultrathin (≤5nm) foils, reaching energies up to ∝35MeV. The acceleration process was studied in simulations well-adapted to the experiments, indicating the transition from plasma to free electron dynamics as the target thickness is reduced to the few nanometer range. The experience gained from those

Relativistic Coulomb Fission

Science.gov (United States)

Norbury, John W.

1992-01-01

Nuclear fission reactions induced by the electromagnetic field of relativistic nuclei are studied for energies relevant to present and future relativistic heavy ion accelerators. Cross sections are calculated for U-238 and Pu-239 fission induced by C-12, Si-28, Au-197, and U-238 projectiles. It is found that some of the cross sections can exceed 10 b.

Relativistic Shock Acceleration

International Nuclear Information System (INIS)

Duffy, P.; Downes, T.P.; Gallant, Y.A.; Kirk, J.G.

1999-01-01

In this paper we briefly review the basic theory of shock waves in relativistic hydrodynamics and magneto-hydrodynamics, emphasising some astrophysically interesting cases. We then present an overview of the theory of particle acceleration at such shocks describing the methods used to calculate the spectral indices of energetic particles. Recent results on acceleration at ultra-relativistic shocks are discussed. (author)

An undergraduate exercise in the first law of relativistic thermodynamics

International Nuclear Information System (INIS)

Gueemez, J

2010-01-01

The isothermal compression of an ideal gas is analysed using a relativistic thermodynamics formalism based on the principle of inertia of energy (Einstein's equation) and the asynchronous formulation (Cavalleri and Salgarelli 1969 Nuovo Cimento 42 722-54), which is similar to the formalism developed by van Kampen (1968 Phys. Rev. 173 295-301) and Hamity (1969 Phys. Rev. 187 1745-52). In this 4-vector Minkowski formalism mechanical and thermodynamical processes are described by the first law of thermodynamics expressed as ΔU μ = W μ + Q μ , in a Lorentz covariant way. This exercise is considered useful for undergraduate physics students interested in foundations of physics, with the only prerequisites in first courses in thermodynamics and special relativity.

Relativistic impulse dynamics.

Science.gov (United States)

Swanson, Stanley M

2011-08-01

Classical electrodynamics has some annoying rough edges. The self-energy of charges is infinite without a cutoff. The calculation of relativistic trajectories is difficult because of retardation and an average radiation reaction term. By reconceptuallizing electrodynamics in terms of exchanges of impulses rather than describing it by forces and potentials, we eliminate these problems. A fully relativistic theory using photonlike null impulses is developed. Numerical calculations for a two-body, one-impulse-in-transit model are discussed. A simple relationship between center-of-mass scattering angle and angular momentum was found. It reproduces the Rutherford cross section at low velocities and agrees with the leading term of relativistic distinguishable-particle quantum cross sections (Møller, Mott) when the distance of closest approach is larger than the Compton wavelength of the particle. Magnetism emerges as a consequence of viewing retarded and advanced interactions from the vantage point of an instantaneous radius vector. Radiation reaction becomes the local conservation of energy-momentum between the radiating particle and the emitted impulse. A net action is defined that could be used in developing quantum dynamics without potentials. A reinterpretation of Newton's laws extends them to relativistic motion.

Bose-Einstein condensation of a charged relativistic ideal gas in a general homogeneous magnetic field

International Nuclear Information System (INIS)

Toms, D.J.

1994-01-01

It is shown how the effective action formalism and ζ-function regularization can be used to study Bose-Einstein condensation for a relativistic charged scalar field in a general homogeneous magnetic field in a spacetime of arbitrary dimension. In the special case where the magnetic field has only one component, Bose-Einstein condensation occurs at high temperature only for D≥5 where D is the spatial dimension. When Bose-Einstein condensation does occur the ground-state expectation value of the scalar field is not constant and we determine its value. If the magnetic field has p independent nonzero components we show that the condition for Bose-Einstein condensation is D≥3+2p. In particular, Bose-Einstein condensation can never occur if the magnetic field has all of its independent components nonzero. The problem of Bose-Einstein condensation in a cylindrical box in D spatial dimensions with a uniform magnetic field directed along the axis of the cylinder is also discussed

Scattering in relativistic particle mechanics

International Nuclear Information System (INIS)

De Bievre, S.

1986-01-01

The problem of direct interaction in relativistic particle mechanics has been extensively studied and a variety of models has been proposed avoiding the conclusions of the so-called no-interaction theorems. In this thesis the authors studied scattering in the relativistic two-body problem. He uses the results to analyze gauge invariance in Hamiltonian constraint models and the uniqueness of the symplectic structure in manifestly covariant relativistic particle mechanics. A general geometric framework that underlies approaches to relativistic particle mechanics is presented and the kinematic properties of the scattering transformation, i.e., those properties that arise solely from the invariance of the theory under the Poincare group are studied. The second part of the analysis of the relativistic two-body scattering problem is devoted to the dynamical properties of the scattering process. Using general geometric arguments, gauge invariance of the scattering transformation in the Todorov-Komar Hamiltonian constraint model is proved. Finally, quantization of the models is discussed

Relativistic finite-temperature Thomas-Fermi model

Science.gov (United States)

Faussurier, Gérald

2017-11-01

We investigate the relativistic finite-temperature Thomas-Fermi model, which has been proposed recently in an astrophysical context. Assuming a constant distribution of protons inside the nucleus of finite size avoids severe divergence of the electron density with respect to a point-like nucleus. A formula for the nuclear radius is chosen to treat any element. The relativistic finite-temperature Thomas-Fermi model matches the two asymptotic regimes, i.e., the non-relativistic and the ultra-relativistic finite-temperature Thomas-Fermi models. The equation of state is considered in detail. For each version of the finite-temperature Thomas-Fermi model, the pressure, the kinetic energy, and the entropy are calculated. The internal energy and free energy are also considered. The thermodynamic consistency of the three models is considered by working from the free energy. The virial question is also studied in the three cases as well as the relationship with the density functional theory. The relativistic finite-temperature Thomas-Fermi model is far more involved than the non-relativistic and ultra-relativistic finite-temperature Thomas-Fermi models that are very close to each other from a mathematical point of view.

Relativistic description of atomic nuclei

International Nuclear Information System (INIS)

Krutov, V.A.

1985-01-01

Papers on the relativistic description of nuclei are reviewed. The Brown and Rho ''small'' bag'' model is accepted for hardrons. Meson exchange potentials of the nucleon-nucleon interaction have been considered. Then the transition from a system of two interacting nucleons has been performed to the relativistic nucleus description as a multinucleon system on the basis of OBEP (one-boson exchange potential). The proboem of OPEP (one-pion-exchange potential) inclusion to a relativistic scheme is discussed. Simplicity of calculations and attractiveness of the Walecka model for specific computations and calculations was noted. The relativistic model of nucleons interacting through ''effective'' scalar and vector boson fields was used in the Walacka model for describing neutronaand nuclear mater matters

A new relativistic viscous hydrodynamics code and its application to the Kelvin-Helmholtz instability in high-energy heavy-ion collisions

Energy Technology Data Exchange (ETDEWEB)

Okamoto, Kazuhisa [Nagoya University, Department of Physics, Nagoya (Japan); Nonaka, Chiho [Nagoya University, Department of Physics, Nagoya (Japan); Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya (Japan); Duke University, Department of Physics, Durham, NC (United States)

2017-06-15

We construct a new relativistic viscous hydrodynamics code optimized in the Milne coordinates. We split the conservation equations into an ideal part and a viscous part, using the Strang spitting method. In the code a Riemann solver based on the two-shock approximation is utilized for the ideal part and the Piecewise Exact Solution (PES) method is applied for the viscous part. We check the validity of our numerical calculations by comparing analytical solutions, the viscous Bjorken's flow and the Israel-Stewart theory in Gubser flow regime. Using the code, we discuss possible development of the Kelvin-Helmholtz instability in high-energy heavy-ion collisions. (orig.)

A new relativistic viscous hydrodynamics code and its application to the Kelvin-Helmholtz instability in high-energy heavy-ion collisions

Science.gov (United States)

Okamoto, Kazuhisa; Nonaka, Chiho

2017-06-01

We construct a new relativistic viscous hydrodynamics code optimized in the Milne coordinates. We split the conservation equations into an ideal part and a viscous part, using the Strang spitting method. In the code a Riemann solver based on the two-shock approximation is utilized for the ideal part and the Piecewise Exact Solution (PES) method is applied for the viscous part. We check the validity of our numerical calculations by comparing analytical solutions, the viscous Bjorken's flow and the Israel-Stewart theory in Gubser flow regime. Using the code, we discuss possible development of the Kelvin-Helmholtz instability in high-energy heavy-ion collisions.

Relativistic Jahn-Teller effect in tetrahedral systems

International Nuclear Information System (INIS)

Opalka, Daniel; Domcke, Wolfgang; Segado, Mireia; Poluyanov, Leonid V.

2010-01-01

It is shown that orbitally degenerate states in highly symmetric systems are split by Jahn-Teller forces which are of relativistic origin (that is, they arise from the spin-orbit coupling operator). For the example of tetrahedral systems, the relativistic Jahn-Teller Hamiltonians of orbitally degenerate electronic states with spin 1/2 are derived. While both electrostatic and relativistic forces contribute to the Jahn-Teller activity of vibrational modes of E and T 2 symmetry in 2 T 2 states of tetrahedral systems, the electrostatic and relativistic Jahn-Teller couplings are complementary for 2 E states: The E mode is Jahn-Teller active through electrostatic forces, while the T 2 mode is Jahn-Teller active through the relativistic forces. The relativistic Jahn-Teller parameters have been computed with ab initio relativistic electronic-structure methods. It is shown for the example of the tetrahedral cluster cations of the group V elements that the relativistic Jahn-Teller couplings can be of the same order of magnitude as the familiar electrostatic Jahn-Teller couplings for the heavier elements.

Analytic Scalings of the Constant-Neutralization Beam Envelope Equation, with Applications

International Nuclear Information System (INIS)

McCarrick, J F

2007-01-01

Neutralized transport of relativistic electron beams can achieved in various circumstances. In one form, the beam is transported through a plasma, either pre-formed or beam generated, where the plasma electrons are ejected due to the space charge influence of the beam. The beam can be fully neutralized this way if the plasma is sufficiently dense. Typically, the transport physics of concern in this case are the various macro- and micro-instabilities that can develop due to interactions of the beam with the plasma; charge and current neutralization are certainly important but tend to be just one set of concerns among many. The study of beam/plasma interactions has been active for many years [e.g. 1]. In a different scenario, the beam impinges on a plasma with a sharp boundary (as maintained on the timescale of a beam pulse) and, via space charge, extracts ions from the plasma; extraction energies can be hundreds of kilovolts in the case of tightly focused, high current beams. In this case, the ions have a lower density than the beam and are not accompanied by a plasma electron population; the main transport issue is charge neutralization. Such a sharply bounded plasma can occur via ionization of surface impurities from a solid target; the transport of the beam through this thin layer is typically not of interest relative to the transport upstream of the surface and the beam/target interactions beyond the surface. Since the partial neutralization of the beam changes its focusing characteristics on the target, and since the high extraction energy means the ion column is moving rapidly into the beam and introducing strong time variation, this 'backstreaming ion' phenomenon has been an area of active study in the transport of the high-intensity electron beams used in radiographic accelerators (see [2] for an example of such machines). However, much of the work has been experimental [3] and numerical [4]. The conceptual understanding provided by pencil-and-paper analysis

The relativistic rocket

Energy Technology Data Exchange (ETDEWEB)

Antippa, Adel F [Departement de Physique, Universite du Quebec a Trois-Rivieres, Trois-Rivieres, Quebec G9A 5H7 (Canada)

2009-05-15

We solve the problem of the relativistic rocket by making use of the relation between Lorentzian and Galilean velocities, as well as the laws of superposition of successive collinear Lorentz boosts in the limit of infinitesimal boosts. The solution is conceptually simple, and technically straightforward, and provides an example of a powerful method that can be applied to a wide range of special relativistic problems of linear acceleration.

Relativistic length agony continued

Directory of Open Access Journals (Sweden)

Redžić D.V.

2014-01-01

Full Text Available We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redžić 2008b, we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the ‘pole in a barn’ paradox. [Projekat Ministarstva nauke Republike Srbije, br. 171028

An investigation of relativistic microscopic optical potential in terms of relativistic Brueckner-Bethe-Goldstone equation

International Nuclear Information System (INIS)

Chen Baoqiu; Ma Zhongyu

1992-01-01

Relativistic microscopic optical potential of nucleon-nucleus is derived from the relativistic Brueckner-Bethe-Goldstone (RBBG) equation. The complex effective mass of a nucleon is determined by a fit to 200 MeV p- 40 Ca scattering data. The relativistic microscopic optical potentials with this effective mass are obtained from RBBG for p- 16O , 40 Ca, 90 Zr and 208 Pb scattering in energy range from 160 to 800 MeV. The microscopic optical potential is used to study the proton- 40 Ca scattering problem at 200 MeV. The results, such as differential cross section, analyzing power and spin rotation function are compared with those calculated from phenomenological relativistic optical potential

Leading order relativistic chiral nucleon-nucleon interaction

Science.gov (United States)

Ren, Xiu-Lei; Li, Kai-Wen; Geng, Li-Sheng; Long, Bingwei; Ring, Peter; Meng, Jie

2018-01-01

Motivated by the successes of relativistic theories in studies of atomic/molecular and nuclear systems and the need for a relativistic chiral force in relativistic nuclear structure studies, we explore a new relativistic scheme to construct the nucleon-nucleon interaction in the framework of covariant chiral effective field theory. The chiral interaction is formulated up to leading order with covariant power counting and a Lorentz invariant chiral Lagrangian. We find that the relativistic scheme induces all six spin operators needed to describe the nuclear force. A detailed investigation of the partial wave potentials shows a better description of the {}1S0 and {}3P0 phase shifts than the leading order Weinberg approach, and similar to that of the next-to-leading order Weinberg approach. For the other partial waves with angular momenta J≥slant 1, the relativistic results are almost the same as their leading order non-relativistic counterparts. )

RANKINE-HUGONIOT RELATIONS IN RELATIVISTIC COMBUSTION WAVES

International Nuclear Information System (INIS)

Gao Yang; Law, Chung K.

2012-01-01

As a foundational element describing relativistic reacting waves of relevance to astrophysical phenomena, the Rankine-Hugoniot relations classifying the various propagation modes of detonation and deflagration are analyzed in the relativistic regime, with the results properly degenerating to the non-relativistic and highly relativistic limits. The existence of negative-pressure downstream flows is noted for relativistic shocks, which could be of interest in the understanding of the nature of dark energy. Entropy analysis for relativistic shock waves is also performed for relativistic fluids with different equations of state (EoS), denoting the existence of rarefaction shocks in fluids with adiabatic index Γ < 1 in their EoS. The analysis further shows that weak detonations and strong deflagrations, which are rare phenomena in terrestrial environments, are expected to exist more commonly in astrophysical systems because of the various endothermic reactions present therein. Additional topics of relevance to astrophysical phenomena are also discussed.

Bound states for a neutral particle analogous to a quantum dot induced by the non-inertial effects of the Fermi-Walker reference frame

International Nuclear Information System (INIS)

Bakke, Knut

2010-01-01

We study the appearance of bound states analogous to a quantum dot, proposed by Tan and Inkson (1996) , in the non-relativistic quantum dynamics of a neutral particle with permanent magnetic dipole moment induced by the non-inertial effects of the Fermi-Walker reference frame.

Methyl Cation Affinities of Neutral and Anionic Maingroup-Element Hydrides: Trends Across the Periodic Table and Correlation with Proton Affinities

NARCIS (Netherlands)

Mulder, R. Joshua; Guerra, Celia Fonseca; Bickelhaupt, F. Matthias

2010-01-01

We have computed the methyl cation affinities in the gas phase of archetypal anionic and neutral bases across the periodic table using ZORA-relativistic density functional theory (DFT) at BP86/QZ4P//BP86/TZ2P. The main purpose of this work is to provide the methyl cation affinities (and

Search for non-relativistic magnetic monopoles with IceCube

Energy Technology Data Exchange (ETDEWEB)

Aartsen, M.G.; Hill, G.C.; Robertson, S.; Whelan, B.J. [University of Adelaide, School of Chemistry and Physics, Adelaide, SA (Australia); Abbasi, R.; Ahlers, M.; Arguelles, C.; Baker, M.; BenZvi, S.; Chirkin, D.; Day, M.; Desiati, P.; Diaz-Velez, J.C.; Eisch, J.; Fadiran, O.; Feintzeig, J.; Gladstone, L.; Halzen, F.; Hoshina, K.; Jacobsen, J.; Jero, K.; Karle, A.; Kauer, M.; Kelley, J.L.; Kopper, C.; Krasberg, M.; Kurahashi, N.; Landsman, H.; Maruyama, R.; McNally, F.; Merck, M.; Morse, R.; Riedel, B.; Rodrigues, J.P.; Santander, M.; Tobin, M.N.; Toscano, S.; Van Santen, J.; Weaver, C.; Wellons, M.; Wendt, C.; Westerhoff, S.; Whitehorn, N. [University of Wisconsin, Department of Physics and Wisconsin IceCube Particle Astrophysics Center, Madison, WI (United States); Ackermann, M.; Benabderrahmane, M.L.; Berghaus, P.; Bernardini, E.; Bretz, H.P.; Cruz Silva, A.H.; Gluesenkamp, T.; Jacobi, E.; Kaminsky, B.; Karg, T.; Middell, E.; Mohrmann, L.; Nahnhauer, R.; Schoenwald, A.; Shanidze, R.; Spiering, C.; Stoessl, A.; Yanez, J.P. [DESY, Zeuthen (Germany); Adams, J.; Brown, A.M.; Hickford, S.; Macias, O. [University of Canterbury, Department of Physics and Astronomy, Private Bag 4800, Christchurch (New Zealand); Aguilar, J.A.; Christov, A.; Montaruli, T.; Rameez, M.; Vallecorsa, S. [Universite de Geneve, Departement de physique nucleaire et corpusculaire, Geneva (Switzerland); Altmann, D.; Classen, L.; Gora, D.; Kappes, A.; Tselengidou, M. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen Centre for Astroparticle Physics, Erlangen (Germany); Arlen, T.C.; De Andre, J.P.A.M.; DeYoung, T.; Dunkman, M.; Eagan, R.; Groh, J.C.; Huang, F.; Quinnan, M.; Smith, M.W.E.; Stanisha, N.A.; Tesic, G. [Pennsylvania State University, Department of Physics, University Park, PA (United States); Auffenberg, J.; Bissok, M.; Blumenthal, J.; Gretskov, P.; Haack, C.; Hallen, P.; Heinen, D.; Jagielski, K.; Kriesten, A.; Krings, K.; Leuermann, M.; Paul, L.; Raedel, L.; Reimann, R.; Schoenen, S.; Schukraft, A.; Vehring, M.; Wallraff, M.; Wiebusch, C.H.; Zierke, S. [RWTH Aachen University, III. Physikalisches Institut, Aachen (Germany); Bai, X.; Evenson, P.A.; Gaisser, T.K.; Gonzalez, J.G.; Hussain, S.; Kuwabara, T.; Ruzybayev, B.; Seckel, D.; Stanev, T.; Tamburro, A.; Tilav, S. [University of Delaware, Bartol Research Institute and Department of Physics and Astronomy, Newark, DE (United States); Barwick, S.W.; Yodh, G. [University of California, Department of Physics and Astronomy, Irvine, CA (United States); Baum, V.; Eberhardt, B.; Koepke, L.; Kroll, G.; Luenemann, J.; Sander, H.G.; Schatto, K.; Wiebe, K. [University of Mainz, Institute of Physics, Mainz (Germany); Bay, R.; Filimonov, K.; Price, P.B.; Woschnagg, K. [University of California, Department of Physics, Berkeley, CA (United States); Beatty, J.J. [Ohio State University, Department of Physics and Center for Cosmology and Astro-Particle Physics, Columbus, OH (United States); Ohio State University, Department of Astronomy, Columbus, OH (United States); Becker Tjus, J.; Eichmann, B.; Fedynitch, A.; Saba, S.M.; Schoeneberg, S.; Unger, E. [Ruhr-Universitaet Bochum, Fakultaet fuer Physik and Astronomie, Bochum (Germany); Becker, K.H.; Bindig, D.; Fischer-Wasels, T.; Helbing, K.; Hoffmann, R.; Klaes, J.; Kopper, S.; Naumann, U.; Obertacke, A.; Omairat, A.; Posselt, J.; Soldin, D.; Tepe, A. [University of Wuppertal, Department of Physics, Wuppertal (Germany); Berley, D.; Blaufuss, E.; Christy, B.; Goodman, J.A.; Hellauer, R.; Hoffman, K.D.; Huelsnitz, W.; Meagher, K.; Olivas, A.; Redl, P.; Richman, M.; Schmidt, T.; Sullivan, G.W.; Wissing, H. [University of Maryland, Department of Physics, College Park, MD (United States); Bernhard, A.; Coenders, S.; Gross, A.; Leute, J.; Resconi, E.; Schulz, O.; Sestayo, Y. [T.U. Munich, Garching (Germany); Besson, D.Z. [University of Kansas, Department of Physics and Astronomy, Lawrence, KS (United States); Binder, G.; Gerhardt, L.; Ha, C.; Klein, S.R.; Miarecki, S. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Boersma, D.J.; Botner, O.; Euler, S.; Hallgren, A.; Perez de los Heros, C.; Stroem, R.; Taavola, H. [Uppsala University, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); Bohm, C.; Danninger, M.; Finley, C.; Flis, S.; Hulth, P.O.; Hultqvist, K.; Walck, C.; Wolf, M.; Zoll, M. [Stockholm University, Oskar Klein Centre and Department of Physics, Stockholm (Sweden); Bose, D.; Rott, C. [Sungkyunkwan University, Department of Physics, Suwon (Korea, Republic of); Collaboration: IceCube Collaboration; and others

2014-07-15

The IceCube Neutrino Observatory is a large Cherenkov detector instrumenting 1 km{sup 3} of Antarctic ice. The detector can be used to search for signatures of particle physics beyond the Standard Model. Here, we describe the search for non-relativistic, magnetic monopoles as remnants of the Grand Unified Theory (GUT) era shortly after the Big Bang. Depending on the underlying gauge group these monopoles may catalyze the decay of nucleons via the Rubakov-Callan effect with a cross section suggested to be in the range of 10{sup -27} to 10{sup -21} cm{sup 2}. In IceCube, the Cherenkov light from nucleon decays along the monopole trajectory would produce a characteristic hit pattern. This paper presents the results of an analysis of first data taken from May 2011 until May 2012 with a dedicated slow particle trigger for DeepCore, a subdetector of IceCube. A second analysis provides better sensitivity for the brightest non-relativistic monopoles using data taken from May 2009 until May 2010. In both analyses no monopole signal was observed. For catalysis cross sections of 10{sup -22} (10{sup -24}) cm{sup 2} the flux of non-relativistic GUT monopoles is constrained up to a level of Φ{sub 90} ≤ 10{sup -18} (10{sup -17}) cm{sup -2} s{sup -1} sr{sup -1} at a 90 % confidence level, which is three orders of magnitude below the Parker bound. The limits assume a dominant decay of the proton into a positron and a neutral pion. These results improve the current best experimental limits by one to two orders of magnitude, for a wide range of assumed speeds and catalysis cross sections. (orig.)

Relativistic quantum mechanics

International Nuclear Information System (INIS)

Ollitrault, J.Y.

1998-12-01

These notes form an introduction to relativistic quantum mechanics. The mathematical formalism has been reduced to the minimum in order to enable the reader to calculate elementary physical processes. The second quantification and the field theory are the logical followings of this course. The reader is expected to know analytical mechanics (Lagrangian and Hamiltonian), non-relativistic quantum mechanics and some basis of restricted relativity. The purpose of the first 3 chapters is to define the quantum mechanics framework for already known notions about rotation transformations, wave propagation and restricted theory of relativity. The next 3 chapters are devoted to the application of relativistic quantum mechanics to a particle with 0,1/5 and 1 spin value. The last chapter deals with the processes involving several particles, these processes require field theory framework to be thoroughly described. (A.C.)

Relativistic Quantum Revivals

International Nuclear Information System (INIS)

Strange, P.

2010-01-01

Quantum revivals are now a well-known phenomena within nonrelativistic quantum theory. In this Letter we display the effects of relativity on revivals and quantum carpets. It is generally believed that revivals do not occur within a relativistic regime. Here we show that while this is generally true, it is possible, in principle, to set up wave packets with specific mathematical properties that do exhibit exact revivals within a fully relativistic theory.

Towards relativistic quantum geometry

Energy Technology Data Exchange (ETDEWEB)

Ridao, Luis Santiago [Instituto de Investigaciones Físicas de Mar del Plata (IFIMAR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mar del Plata (Argentina); Bellini, Mauricio, E-mail: mbellini@mdp.edu.ar [Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350, C.P. 7600, Mar del Plata (Argentina); Instituto de Investigaciones Físicas de Mar del Plata (IFIMAR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mar del Plata (Argentina)

2015-12-17

We obtain a gauge-invariant relativistic quantum geometry by using a Weylian-like manifold with a geometric scalar field which provides a gauge-invariant relativistic quantum theory in which the algebra of the Weylian-like field depends on observers. An example for a Reissner–Nordström black-hole is studied.

Radiation dominated relativistic current sheets

International Nuclear Information System (INIS)

Jaroschek, C.H.

2008-01-01

Relativistic Current Sheets (RCS) feature plasma instabilities considered as potential key to magnetic energy dissipation and non-thermal particle generation in Poynting flux dominated plasma flows. We show in a series of kinetic plasma simulations that the physical nature of non-linear RCS evolution changes in the presence of incoherent radiation losses: In the ultra-relativistic regime (i.e. magnetization parameter sigma = 104 defined as the ratio of magnetic to plasma rest frame energy density) the combination of non-linear RCS dynamics and synchrotron emission introduces a temperature anisotropy triggering the growth of the Relativistic Tearing Mode (RTM). As direct consequence the RTM prevails over the Relativistic Drift Kink (RDK) Mode as competitive RCS instability. This is in contrast to the previously studied situation of weakly relativistic RCS (sigma ∼ 1) where the RDK is dominant and most of the plasma is thermalized. The simulations witness the typical life cycle of ultra-relativistic RCS evolving from a violent radiation induced collapse towards a radiation quiescent state in rather classical Sweet-Parker topology. Such a transition towards Sweet-Parker configuration in the late non-linear evolution has immediate consequences for the efficiency of magnetic energy dissipation and non-thermal particle generation. Ceasing dissipation rates directly affect our present understanding of non-linear RCS evolution in conventional striped wind scenarios. (author)

Relativistic gas in a Schwarzschild metric

International Nuclear Information System (INIS)

Kremer, Gilberto M

2013-01-01

A relativistic gas in a Schwarzschild metric is studied within the framework of a relativistic Boltzmann equation in the presence of gravitational fields, where Marle’s model for the collision operator of the Boltzmann equation is employed. The transport coefficients of the bulk and shear viscosities and thermal conductivity are determined from the Chapman–Enskog method. It is shown that the transport coefficients depend on the gravitational potential. Expressions for the transport coefficients in the presence of weak gravitational fields in the non-relativistic (low temperature) and ultra-relativistic (high temperature) limiting cases are given. Apart from the temperature gradient the heat flux has two relativistic terms. The first one, proposed by Eckart, is due to the inertia of energy and represents an isothermal heat flux when matter is accelerated. The other, suggested by Tolman, is proportional to the gravitational potential gradient and indicates that—in the absence of an acceleration field—a state of equilibrium of a relativistic gas in a gravitational field can be attained only if the temperature gradient is counterbalanced by a gravitational potential gradient. (paper)

Relativistic electron mirrors from high intensity laser nanofoil interactions

Energy Technology Data Exchange (ETDEWEB)

Kiefer, Daniel

2012-12-21

The reflection of a laser pulse from a mirror moving close to the speed of light could in principle create an X-ray pulse with unprecedented high brightness owing to the increase in photon energy and accompanying temporal compression by a factor of 4γ{sup 2}, where γ is the Lorentz factor of the mirror. While this scheme is theoretically intriguingly simple and was first discussed by A. Einstein more than a century ago, the generation of a relativistic structure which acts as a mirror is demanding in many different aspects. Recently, the interaction of a high intensity laser pulse with a nanometer thin foil has raised great interest as it promises the creation of a dense, attosecond short, relativistic electron bunch capable of forming a mirror structure that scatters counter-propagating light coherently and shifts its frequency to higher photon energies. However, so far, this novel concept has been discussed only in theoretical studies using highly idealized interaction parameters. This thesis investigates the generation of a relativistic electron mirror from a nanometer foil with current state-of-the-art high intensity laser pulses and demonstrates for the first time the reflection from those structures in an experiment. To achieve this result, the electron acceleration from high intensity laser nanometer foil interactions was studied in a series of experiments using three inherently different high power laser systems and free-standing foils as thin as 3nm. A drastic increase in the electron energies was observed when reducing the target thickness from the micrometer to the nanometer scale. Quasi-monoenergetic electron beams were measured for the first time from ultrathin (≤5nm) foils, reaching energies up to ∝35MeV. The acceleration process was studied in simulations well-adapted to the experiments, indicating the transition from plasma to free electron dynamics as the target thickness is reduced to the few nanometer range. The experience gained from those

Extended Galilean symmetries of non-relativistic strings

Energy Technology Data Exchange (ETDEWEB)

Batlle, Carles [Departament de Matemàtiques and IOC, Universitat Politècnica de Catalunya, EPSEVG,Av. V. Balaguer 1, E-08808 Vilanova i la Geltrú (Spain); Gomis, Joaquim; Not, Daniel [Departament de Física Quàntica i Astrofísica and Institut de Ciències del Cosmos (ICCUB),Universitat de Barcelona,Martí i Franquès 1, E-08028 Barcelona (Spain)

2017-02-09

We consider two non-relativistic strings and their Galilean symmetries. These strings are obtained as the two possible non-relativistic (NR) limits of a relativistic string. One of them is non-vibrating and represents a continuum of non-relativistic massless particles, and the other one is a non-relativistic vibrating string. For both cases we write the generator of the most general point transformation and impose the condition of Noether symmetry. As a result we obtain two sets of non-relativistic Killing equations for the vector fields that generate the symmetry transformations. Solving these equations shows that NR strings exhibit two extended, infinite dimensional space-time symmetries which contain, as a subset, the Galilean symmetries. For each case, we compute the associated conserved charges and discuss the existence of non-central extensions.

Relativistic generalization of strong plasma turbulence

International Nuclear Information System (INIS)

Chian, A.C.-L.

1982-01-01

Two fundamental electrostatic modes of an unmagnetized plasma, namely, ion acoustic mode and Langumir mode are studied. Previous theories are generalized to include the effect of relativistic mass variations. The existence of relativistic ion acoustic solitons is demonstrated. In addition, it is shown that simple, relativistic Langumir solitons do not exist in a infinite plasma. (L.C.) [pt

Nuclear response theory for spin-isospin excitations in a relativistic quasiparticle-phonon coupling framework

Energy Technology Data Exchange (ETDEWEB)

Robin, Caroline; Litvinova, Elena [Western Michigan University, Department of Physics, Kalamazoo, MI (United States)

2016-07-15

A new theoretical approach to spin-isospin excitations in open-shell nuclei is presented. The developed method is based on the relativistic meson-exchange nuclear Lagrangian of Quantum Hadrodynamics and extends the response theory for superfluid nuclear systems beyond relativistic quasiparticle random phase approximation in the proton-neutron channel (pn-RQRPA). The coupling between quasiparticle degrees of freedom and collective vibrations (phonons) introduces a time-dependent effective interaction, in addition to the exchange of pion and ρ-meson taken into account without retardation. The time-dependent contributions are treated in the resonant time-blocking approximation, in analogy to the previously developed relativistic quasiparticle time-blocking approximation (RQTBA) in the neutral (non-isospin-flip) channel. The new method is called proton-neutron RQTBA (pn-RQTBA) and is applied to the Gamow-Teller resonance in a chain of neutron-rich nickel isotopes {sup 68-78}Ni. A strong fragmentation of the resonance along with quenching of the strength, as compared to pn-RQRPA, is obtained. Based on the calculated strength distribution, beta-decay half-lives of the considered isotopes are computed and compared to pn-RQRPA half-lives and to experimental data. It is shown that a considerable improvement of the half-life description is obtained in pn-RQTBA because of the spreading effects, which bring the lifetimes to a very good quantitative agreement with data. (orig.)

Equilibrium and stability properties of relativistic electron rings and E-layers

International Nuclear Information System (INIS)

Uhm, H.

1976-01-01

Equilibrium and stability properties of magnetically confined partially-neutralized thin electron ring and E-layer are investigated using the Vlasov-Maxwell equations. The analysis is carried out within the context of the assumption that the minor dimensions (a,b) of the system are much less than the collisionless skin depth (c/antiω/sub p/). The equilibrium configuration of the E-layer is assumed to be an infinitely long, azimuthally symmetric hollow electron beam which is aligned parallel to a uniform axial magnetic field. On the other hand, the electron ring is located at the midplane of an externally imposed mirror field which acts to confine the ring both axially and radially. The equilibrium properties of the E-layer and electron ring are obtained self-consistently for several choices of equilibrium electron distribution function. The negative-mass instability analysis is carried out for the relativistic E-layer equilibrium in which all of the electrons have the same transverse energy and a spread in canonical angular momentum, assuming a fixed ion background. The ion resonance instability properties are investigated for a relativistic nonneutral E-layer aligned parallel to a uniform magnetic field and located between two ground coaxial cylindrical conductors. The stability properties of a nonrelativistic electron ring is investigated within the framework of the linearized Vlasov-Poisson equations. The dispersion relation is obtained for the self-consistent electron distribution function in which all electrons have the same value of energy an the same value of canonical angular momentum. The positive ions in the electron ring are assumed to form an immobile partially neutralizing background. The stability criteria as well as the instability growth rates are derived and discussed including the effect of geometrical configuration of the system. Equilibrium space-charge effects play a significant role in stability behavior

The Wigner function in the relativistic quantum mechanics

Energy Technology Data Exchange (ETDEWEB)

Kowalski, K., E-mail: kowalski@uni.lodz.pl; Rembieliński, J.

2016-12-15

A detailed study is presented of the relativistic Wigner function for a quantum spinless particle evolving in time according to the Salpeter equation. - Highlights: • We study the Wigner function for a quantum spinless relativistic particle. • We discuss the relativistic Wigner function introduced by Zavialov and Malokostov. • We introduce relativistic Wigner function based on the standard definition. • We find analytic expressions for relativistic Wigner functions.

New relativistic generalization of the Heisenberg commutation relations

International Nuclear Information System (INIS)

Bohm, A.; Loewe, M.; Magnollay, P.; Tarlini, M.; Aldinger, R.R.; Kielanowski, P.

1984-01-01

A relativistic generalization of the Heisenberg commutation relations is suggested which is different from the conventional ones used for the intrinsic coordinates and momenta in the relativistic oscillator model and the relativistic string. This new quantum relativistic oscillator model is determined by the requirement that it gives a unified description of relativistic vibrations and rotations and contracts in the nonrelativistic limit c -1 →0 into the usual nonrelativistic harmonic oscillator

Relativistic positioning systems: Numerical simulations

Science.gov (United States)

Puchades Colmenero, Neus

The position of users located on the Earth's surface or near it may be found with the classic positioning systems (CPS). Certain information broadcast by satellites of global navigation systems, as GPS and GALILEO, may be used for positioning. The CPS are based on the Newtonian formalism, although relativistic post-Newtonian corrections are done when they are necessary. This thesis contributes to the development of a different positioning approach, which is fully relativistic from the beginning. In the relativistic positioning systems (RPS), the space-time position of any user (ship, spacecraft, and so on) can be calculated with the help of four satellites, which broadcast their proper times by means of codified electromagnetic signals. In this thesis, we have simulated satellite 4-tuples of the GPS and GALILEO constellations. If a user receives the signals from four satellites simultaneously, the emission proper times read -after decoding- are the user "emission coordinates". In order to find the user "positioning coordinates", in an appropriate almost inertial reference system, there are two possibilities: (a) the explicit relation between positioning and emission coordinates (broadcast by the satellites) is analytically found or (b) numerical codes are designed to calculate the positioning coordinates from the emission ones. Method (a) is only viable in simple ideal cases, whereas (b) allows us to consider realistic situations. In this thesis, we have designed numerical codes with the essential aim of studying two appropriate RPS, which may be generalized. Sometimes, there are two real users placed in different positions, which receive the same proper times from the same satellites; then, we say that there is bifurcation, and additional data are needed to choose the real user position. In this thesis, bifurcation is studied in detail. We have analyzed in depth two RPS models; in both, it is considered that the satellites move in the Schwarzschild's space

Random phase approximation in relativistic approach

International Nuclear Information System (INIS)

Ma Zhongyu; Yang Ding; Tian Yuan; Cao Ligang

2009-01-01

Some special issues of the random phase approximation(RPA) in the relativistic approach are reviewed. A full consistency and proper treatment of coupling to the continuum are responsible for the successful application of the RPA in the description of dynamical properties of finite nuclei. The fully consistent relativistic RPA(RRPA) requires that the relativistic mean filed (RMF) wave function of the nucleus and the RRPA correlations are calculated in a same effective Lagrangian and the consistent treatment of the Dirac sea of negative energy states. The proper treatment of the single particle continuum with scattering asymptotic conditions in the RMF and RRPA is discussed. The full continuum spectrum can be described by the single particle Green's function and the relativistic continuum RPA is established. A separable form of the paring force is introduced in the relativistic quasi-particle RPA. (authors)

High current relativistic beam propagates stably in gas surrounded by nonconducting walls

International Nuclear Information System (INIS)

Clark, J.C.

1977-01-01

LLL has been studying the propagation of high current electron beams for a number of years to understand their behavior for use in a variety of experimental uses. Our latest experiments have shown that a mildly relativistic electron beam of 10 to 15 kA and a pulse width of 30 to 40 ns can propagate stably and with no net current transfer in insulating tubes filled with neutral gases. These experiments have been performed in the Magnetic Fusion Energy program where Electronics Engineering has been operating an electron beam accelerator, designing some of the diagnostics, such as laser interferometers, and performing the experiments. This article briefly describes our experimental observations

GRHydro: a new open-source general-relativistic magnetohydrodynamics code for the Einstein toolkit

International Nuclear Information System (INIS)

Mösta, Philipp; Haas, Roland; Ott, Christian D; Reisswig, Christian; Mundim, Bruno C; Faber, Joshua A; Noble, Scott C; Bode, Tanja; Löffler, Frank; Schnetter, Erik

2014-01-01

We present the new general-relativistic magnetohydrodynamics (GRMHD) capabilities of the Einstein toolkit, an open-source community-driven numerical relativity and computational relativistic astrophysics code. The GRMHD extension of the toolkit builds upon previous releases and implements the evolution of relativistic magnetized fluids in the ideal MHD limit in fully dynamical spacetimes using the same shock-capturing techniques previously applied to hydrodynamical evolution. In order to maintain the divergence-free character of the magnetic field, the code implements both constrained transport and hyperbolic divergence cleaning schemes. We present test results for a number of MHD tests in Minkowski and curved spacetimes. Minkowski tests include aligned and oblique planar shocks, cylindrical explosions, magnetic rotors, Alfvén waves and advected loops, as well as a set of tests designed to study the response of the divergence cleaning scheme to numerically generated monopoles. We study the code’s performance in curved spacetimes with spherical accretion onto a black hole on a fixed background spacetime and in fully dynamical spacetimes by evolutions of a magnetized polytropic neutron star and of the collapse of a magnetized stellar core. Our results agree well with exact solutions where these are available and we demonstrate convergence. All code and input files used to generate the results are available on http://einsteintoolkit.org. This makes our work fully reproducible and provides new users with an introduction to applications of the code. (paper)

Relativistic mean field model for entrainment in general relativistic superfluid neutron stars

International Nuclear Information System (INIS)

Comer, G.L.; Joynt, R.

2003-01-01

General relativistic superfluid neutron stars have a significantly more intricate dynamics than their ordinary fluid counterparts. Superfluidity allows different superfluid (and superconducting) species of particles to have independent fluid flows, a consequence of which is that the fluid equations of motion contain as many fluid element velocities as superfluid species. Whenever the particles of one superfluid interact with those of another, the momentum of each superfluid will be a linear combination of both superfluid velocities. This leads to the so-called entrainment effect whereby the motion of one superfluid will induce a momentum in the other superfluid. We have constructed a fully relativistic model for entrainment between superfluid neutrons and superconducting protons using a relativistic σ-ω mean field model for the nucleons and their interactions. In this context there are two notions of 'relativistic': relativistic motion of the individual nucleons with respect to a local region of the star (i.e. a fluid element containing, say, an Avogadro's number of particles), and the motion of fluid elements with respect to the rest of the star. While it is the case that the fluid elements will typically maintain average speeds at a fraction of that of light, the supranuclear densities in the core of a neutron star can make the nucleons themselves have quite high average speeds within each fluid element. The formalism is applied to the problem of slowly rotating superfluid neutron star configurations, a distinguishing characteristic being that the neutrons can rotate at a rate different from that of the protons

Quantum gates via relativistic remote control

Energy Technology Data Exchange (ETDEWEB)

Martín-Martínez, Eduardo, E-mail: emartinm@uwaterloo.ca [Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Dept. Applied Math., University of Waterloo, Ontario, N2L 3G1 (Canada); Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada); Sutherland, Chris [Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada)

2014-12-12

We harness relativistic effects to gain quantum control on a stationary qubit in an optical cavity by controlling the non-inertial motion of a different probe atom. Furthermore, we show that by considering relativistic trajectories of the probe, we enhance the efficiency of the quantum control. We explore the possible use of these relativistic techniques to build 1-qubit quantum gates.

Relativistic BCS-BEC Crossover at Quark Level

Directory of Open Access Journals (Sweden)

Zhuang P.

2010-10-01

Full Text Available The non-relativistic G0G formalism of BCS-BEC crossover at finite temperature is extended to relativistic fermion systems. The theory recovers the BCS mean field approximation at zero temperature and the non-relativistic results in a proper limit. For massive fermions, when the coupling strength increases, there exist two crossovers from the weak coupling BCS superfluid to the non-relativistic BEC state and then to the relativistic BEC state. For color superconductivity at moderate baryon density, the matter is in the BCS-BEC crossover region, and the behavior of the pseudogap is quite similar to that found in high temperature superconductors.

Nonlinear dynamic of interaction of the relativistic electron beam with plasma

International Nuclear Information System (INIS)

Dorofeenko, V.G.; Krasovitskii, V.B.; Osmolovsky, S.I.

1994-01-01

Quasi-transverse instability of thin relativistic electron beam in a dense plasma is studied numerically and analytically in a broad range of the frequency of the beam modulation and external longitudinal magnetic field. It is shown that the nonlinear stage of solution depends on the increment of the instability. It is permitted to classify possible nonlinear solutions and also to determine optimal regimes of the modulation for transport of beam along magnetic field in a plasma without substantial radial divergence. Numerical calculations show, that injection of the bunches with parameters, corresponding nonlinear regime of the beam's instability, in neutrally-charged plasma permits to output on the stationary regime without loss of particles

Pion propagator in relativistic quantum field theories of the nuclear many-body problem

International Nuclear Information System (INIS)

Matsui, T.; Serot, B.D.

1982-01-01

Pion interactions in the nuclear medium are studied using renormalizable relativistic quantum field theories. Previous studies using pseudoscalar πN coupling encountered difficulties due to the large strength of the πNN vertex. We therefore formulate renormalizable field theories with pseudovector πN coupling using techniques introduced by Weinberg and Schwinger. Calculations are performed for two specific models; the scalar-vector theory of Walecka, extended to include π and rho mesons in a non-chiral fashion, and the linear sigma-model with an additional neutral vector meson. Both models qualitatively reproduce low-energy πN phenomenology and lead to nuclear matter saturation in the relativistic Hartree formalism, which includes baryon vacuum fluctuations. The pions propagator is evaluated in the one-nucleon-loop approximation, which corresponds to a relativistic random-phase approximation built on the Hartree ground state. Virtual NN-bar loops are included, and suitable renormalization techniques are illustrated. The local-density approximation is used to compare the threshold pion self-energy to the s-wave pion-nucleus optical potential. In the non-chiral model, s-wave pion-nucleus scattering is too large in both pseudoscalar and pseudovector calculations, indicating that additional constraints must be imposed on the Lagrangian. In the chiral model, the threshold self-energy vanishes automatically in the pseudovector case, but does so for pseudoscalar coupling only if the baryon effective mass is chosen self-consistently Since extrapolation from free space to nuclear density can lead to large effects, pion propagation in the medium can determine which πN coupling is more suitable for the relativistic nuclear many-body problem. Conversely, pion interactions constrain the model Lagrangian and the nuclear matter equation of state. An approximately chiral model with pseudovector coupling is favored

RELATIVISTIC CYCLOTRON INSTABILITY IN ANISOTROPIC PLASMAS

Energy Technology Data Exchange (ETDEWEB)

López, Rodrigo A.; Moya, Pablo S.; Muñoz, Víctor; Valdivia, J. Alejandro [Departamento de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago (Chile); Navarro, Roberto E.; Araneda, Jaime A. [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Viñas, Adolfo F., E-mail: rlopez186@gmail.com [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, MD 20771 (United States)

2016-11-20

A sufficiently large temperature anisotropy can sometimes drive various types of electromagnetic plasma micro-instabilities, which can play an important role in the dynamics of relativistic pair plasmas in space, astrophysics, and laboratory environments. Here, we provide a detailed description of the cyclotron instability of parallel propagating electromagnetic waves in relativistic pair plasmas on the basis of a relativistic anisotropic distribution function. Using plasma kinetic theory and particle-in-cell simulations, we study the influence of the relativistic temperature and the temperature anisotropy on the collective and noncollective modes of these plasmas. Growth rates and dispersion curves from the linear theory show a good agreement with simulations results.

Relativistic quantum mechanics

CERN Document Server

Horwitz, Lawrence P

2015-01-01

This book describes a relativistic quantum theory developed by the author starting from the E.C.G. Stueckelberg approach proposed in the early 40s. In this framework a universal invariant evolution parameter (corresponding to the time originally postulated by Newton) is introduced to describe dynamical evolution. This theory is able to provide solutions for some of the fundamental problems encountered in early attempts to construct a relativistic quantum theory. A relativistically covariant construction is given for which particle spins and angular momenta can be combined through the usual rotation group Clebsch-Gordan coefficients. Solutions are defined for both the classical and quantum two body bound state and scattering problems. The recently developed quantum Lax-Phillips theory of semigroup evolution of resonant states is described. The experiment of Lindner and coworkers on interference in time is discussed showing how the property of coherence in time provides a simple understanding of the results. Th...

Apparent unambiguousness of relativistic time dilation

International Nuclear Information System (INIS)

Strel'tsov, V.N.

1992-01-01

It is indicated on the definite analogy between the dependence of visible sizes of relativistic objects and period of the wave, emitted by the moving source from the observation conditions ('retradition factor'). It is noted that the definition of time for moving extended objects, led to relativistic dilation, corresponds to the definition of the relativistic (radar) length led to the 'elongation formula'. 10 refs

Slowly rotating general relativistic superfluid neutron stars with relativistic entrainment

International Nuclear Information System (INIS)

Comer, G.L.

2004-01-01

Neutron stars that are cold enough should have two or more superfluids or supercondutors in their inner crusts and cores. The implication of superfluidity or superconductivity for equilibrium and dynamical neutron star states is that each individual particle species that forms a condensate must have its own, independent number density current and equation of motion that determines that current. An important consequence of the quasiparticle nature of each condensate is the so-called entrainment effect; i.e., the momentum of a condensate is a linear combination of its own current and those of the other condensates. We present here the first fully relativistic modeling of slowly rotating superfluid neutron stars with entrainment that is accurate to the second-order in the rotation rates. The stars consist of superfluid neutrons, superconducting protons, and a highly degenerate, relativistic gas of electrons. We use a relativistic σ-ω mean field model for the equation of state of the matter and the entrainment. We determine the effect of a relative rotation between the neutrons and protons on a star's total mass, shape, and Kepler, mass-shedding limit

Balance equations for a relativistic plasma. Pt. 1

International Nuclear Information System (INIS)

Hebenstreit, H.

1983-01-01

Relativistic power moments of the four-momentum are decomposed according to a macroscopic four-velocity. The thus obtained quantities are identified as relativistic generalization of the nonrelativistic orthogonal moments, e.g. diffusion flow, heat flow, pressure, etc. From the relativistic Boltzmann equation we then derive balance equations for these quantities. Explicit expressions for the relativistic mass conservation, energy balance, pressure balance, heat flow balance are presented. The weak relativistic limit is discussed. The derivation of higher order balance equations is sketched. (orig.)

Loading relativistic Maxwell distributions in particle simulations

Science.gov (United States)

Zenitani, S.

2015-12-01

In order to study energetic plasma phenomena by using particle-in-cell (PIC) and Monte-Carlo simulations, we need to deal with relativistic velocity distributions in these simulations. However, numerical algorithms to deal with relativistic distributions are not well known. In this contribution, we overview basic algorithms to load relativistic Maxwell distributions in PIC and Monte-Carlo simulations. For stationary relativistic Maxwellian, the inverse transform method and the Sobol algorithm are reviewed. To boost particles to obtain relativistic shifted-Maxwellian, two rejection methods are newly proposed in a physically transparent manner. Their acceptance efficiencies are 􏰅50% for generic cases and 100% for symmetric distributions. They can be combined with arbitrary base algorithms.

Relativistic solitons and pulsars

Energy Technology Data Exchange (ETDEWEB)

Karpman, V I [Inst. of Terrestrial Magnetism, Ionosphere, and Radio-Wave Propagation, Moscow; Norman, C A; ter Haar, D; Tsytovich, V N

1975-05-01

A production mechanism for stable electron bunches or sheets of localized electric fields is investigated which may account for pulsar radio emission. Possible soliton phenomena in a one-dimensional relativistic plasma are analyzed, and it is suggested that the motion of a relativistic soliton, or ''relaton'', along a curved magnetic-field line may produce radio emission with the correct polarization properties. A general MHD solution is obtained for relatons, the radiation produced by a relativistic particle colliding with a soliton is evaluated, and the emission by a soliton moving along a curved field line is estimated. It is noted that due to a number of severe physical restrictions, curvature radiation is not a very likely solution to the problem of pulsar radio emission. (IAA)

Non-relativistic Limit of a Dirac Polaron in Relativistic Quantum Electrodynamics

CERN Document Server

Arai, A

2006-01-01

A quantum system of a Dirac particle interacting with the quantum radiation field is considered in the case where no external potentials exist. Then the total momentum of the system is conserved and the total Hamiltonian is unitarily equivalent to the direct integral $\\int_{{\\bf R}^3}^\\oplus\\overline{H({\\bf p})}d{\\bf p}$ of a family of self-adjoint operators $\\overline{H({\\bf p})}$ acting in the Hilbert space $\\oplus^4{\\cal F}_{\\rm rad}$, where ${\\cal F}_{\\rm rad}$ is the Hilbert space of the quantum radiation field. The fibre operator $\\overline{H({\\bf p})}$ is called the Hamiltonian of the Dirac polaron with total momentum ${\\bf p} \\in {\\bf R}^3$. The main result of this paper is concerned with the non-relativistic (scaling) limit of $\\overline{H({\\bf p})}$. It is proven that the non-relativistic limit of $\\overline{H({\\bf p})}$ yields a self-adjoint extension of a Hamiltonian of a polaron with spin $1/2$ in non-relativistic quantum electrodynamics.

Nonlinear dynamics of the relativistic standard map

International Nuclear Information System (INIS)

Nomura, Y.; Ichikawa, Y.H.; Horton, W.

1991-04-01

Heating and acceleration of charged particles by RF fields have been extensively investigated by the standard map. The question arises as to how the relativistic effects change the nonlinear dynamical behavior described by the classical standard map. The relativistic standard map is a two parameter (K, Β = ω/kc) family of dynamical systems reducing to the standard map when Β → 0. For Β ≠ 0 the relativistic mass increase suppresses the onset of stochasticity. It shown that the speed of light limits the rate of advance of the phase in the relativistic standard map and introduces KAM surfaces persisting in the high momentum region. An intricate structure of mixing in the higher order periodic orbits and chaotic orbits is analyzed using the symmetry properties of the relativistic standard map. The interchange of the stability of the periodic orbits in the relativistic standard map is also observed and is explained by the local linear stability of the orbits. 12 refs., 16 figs

From structuralism to neutral monism in Arthur S. Eddington's philosophy of physics

Science.gov (United States)

Gherab-Martin, Karim J.

2013-11-01

Arthur S. Eddington is remembered as one of the best astrophysicists and popularizers of physics in the twentieth century. Nevertheless, his stimulating speculations in philosophy produced serious disputes among philosophers of his time, his philosophy remaining linked to idealism and mysticism. This paper shows this label to be misleading and argues for the identification of Eddington's philosophy with a kind of neutral monism regained from Bertrand Russell and influenced by the Gestalt psychology. The concept of structure is fundamental to our argument for the existence of a veiled neutral monism in Eddington's ideas.

How one can construct a consistent relativistic quantum mechanics on the base of a relativistic wave equation

Energy Technology Data Exchange (ETDEWEB)

Gavrilov, S.P. [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil); Gitman, D.M. [Sao Paulo Univ. (USP), SP (Brazil). Inst. de Fisica

2000-07-01

Full text follows: There is a common opinion that the construction of a consistent relativistic quantum mechanics on the base of a relativistic wave equation meets well-known difficulties related to the existence of infinite number of negative energy levels, to the existence of negative vector norms, and so on, which may be only solved in a second-quantized theory, see, for example, two basic papers devoted to the problem L.Foldy, S.Wouthuysen, Phys. Rep.78 (1950) 29; H.Feshbach, F.Villars, Rev. Mod. Phys. 30 (1958) 24, whose arguments are repeated in all handbooks in relativistic quantum theory. Even Dirac trying to solve the problem had turned last years to infinite-component relativistic wave equations, see P.A.M. Dirac, Proc. R. Soc. London, A328 (1972) 1. We believe that a consistent relativistic quantum mechanics may be constructed on the base of an extended (charge symmetric) equation, which unite both a relativistic wave equation for a particle and for an antiparticle. We present explicitly the corresponding construction, see for details hep-th/0003112. We support such a construction by two demonstrations: first, in course of a careful canonical quantization of the corresponding classical action of a relativistic particle we arrive just to such a consistent quantum mechanics; second, we demonstrate that a reduction of the QFT of a corresponding field (scalar, spinor, etc.) to one-particle sector, if such a reduction may be done, present namely this quantum mechanics. (author)

Ultra-relativistic heavy-ion collisions - a hot cocktail of hydrodynamics, resonances and jets

Directory of Open Access Journals (Sweden)

Zabrodin E.

2015-01-01

Full Text Available Ultra-relativistic heavy-ion collisions at energies of RHIC and LHC are considered. For comparison with data the HYDJET++ model, which contains the treatment of both soft and hard processes, is employed. The study focuses mainly on the interplay of ideal hydrodynamics, final state interactions and jets, and its influence on the development of harmonics of the anisotropic flow. It is shown that jets are responsible for violation of the number-of-constituent-quark (NCQ scaling at LHC energies. The interplay between elliptic and triangular flows and their contribution to higher flow harmonics and dihadron angular correlations, including ridge, is also discussed.

Obliquely propagating large amplitude solitary waves in charge neutral plasmas

Directory of Open Access Journals (Sweden)

F. Verheest

2007-01-01

Full Text Available This paper deals in a consistent way with the implications, for the existence of large amplitude stationary structures in general plasmas, of assuming strict charge neutrality between electrons and ions. With the limit of pair plasmas in mind, electron inertia is retained. Combining in a fluid dynamic treatment the conservation of mass, momentum and energy with strict charge neutrality has indicated that nonlinear solitary waves (as e.g. oscillitons cannot exist in electron-ion plasmas, at no angle of propagation with respect to the static magnetic field. Specifically for oblique propagation, the proof has turned out to be more involved than for parallel or perpendicular modes. The only exception is pair plasmas that are able to support large charge neutral solitons, owing to the high degree of symmetry naturally inherent in such plasmas. The nonexistence, in particular, of oscillitons is attributed to the breakdown of the plasma approximation in dealing with Poisson's law, rather than to relativistic effects. It is hoped that future space observations will allow to discriminate between oscillitons and large wave packets, by focusing on the time variability (or not of the phase, since the amplitude or envelope graphs look very similar.

Not All Ideals are Equal: Intrinsic and Extrinsic Ideals in Relationships.

Science.gov (United States)

Rodriguez, Lindsey M; Hadden, Benjamin W; Knee, C Raymond

2015-03-01

The ideal standards model suggests that greater consistency between ideal standards and actual perceptions of one's relationship predicts positive relationship evaluations; however, no research has evaluated whether this differs across types of ideals. A self-determination theory perspective was derived to test whether satisfaction of intrinsic ideals buffers the importance of extrinsic ideals. Participants (N=195) in committed relationships directly and indirectly reported the extent to which their partner met their ideal on two dimensions: intrinsic (e.g., warm, intimate) and extrinsic (e.g., attractive, successful). Relationship need fulfillment and relationship quality were also assessed. Hypotheses were largely supported, such that satisfaction of intrinsic ideals more strongly predicted relationship functioning, and satisfaction of intrinsic ideals buffered the relevance of extrinsic ideals for outcomes.

[The impact of exposure to images of ideally thin models on body dissatisfaction in young French and Italian women].

Science.gov (United States)

Rodgers, R; Chabrol, H

2009-06-01

The thin-ideal of feminine beauty has a strong impact on body image and plays a central part in eating disorders. This ideal is widely promoted by the media images that flood western societies. Although the harmful effects of exposure to thin-ideal media images have been repeatedly demonstrated experimentally in English-speaking western countries, no such studies exist in southern Europe. There is evidence to suggest that the use of average-size models could reduce these negative effects. This study investigates body image amongst French and Italian students following exposure to media images of thin or average-size models, with a neutral or supportive slogan. The data were gathered in three locations: the psychology departments of the Universities of Padua, Italy, and Toulouse, France, and lastly high schools in the Toulouse area. A total of 299 girls took part in the study; their average age was 19.9 years old (S.D.=2.54) In order to investigate the effects of media images, we created three fake advertisements, allegedly promoting body-cream. The first advertisement displayed an ideally-thin model accompanied by a neutral slogan. In the second, the model was average-size with the same neutral slogan. The last advertisement also contained the average-size model, but with a supportive slogan designed to convey acceptance of deviations from the social norms of thinness. The participants first graded themselves on a VAS of body dissatisfaction (0 to 10). On the basis of this score, we created a first group containing girls reporting body dissatisfaction (VAS>or=5), the second with those reporting no body dissatisfaction (VASnegative effects of exposure to thin-ideal media images among students with body dissatisfaction. The use of average-size models in the media and advertising might help reduce these effects. No improvement was obtained via the use of a supportive slogan. These results highlight the importance of media literacy campaigns in the prevention of eating

Relativistic ion acceleration by ultraintense laser interactions

International Nuclear Information System (INIS)

Nakajima, K.; Koga, J.K.; Nakagawa, K.

2001-01-01

There has been a great interest in relativistic particle generation by ultraintense laser interactions with matter. We propose the use of relativistically self-focused laser pulses for the acceleration of ions. Two dimensional PIC simulations are performed, which show the formation of a large positive electrostatic field near the front of a relativistically self-focused laser pulse. Several factors contribute to the acceleration including self-focusing distance, pulse depletion, and plasma density. Ultraintense laser-plasma interactions are capable of generating enormous electrostatic fields of ∼3 TV/m for acceleration of protons with relativistic energies exceeding 1 GeV

Relativistic collective diffusion in one-dimensional systems

Science.gov (United States)

Lin, Gui-Wu; Lam, Yu-Yiu; Zheng, Dong-Qin; Zhong, Wei-Rong

2018-05-01

The relativistic collective diffusion in one-dimensional molecular system is investigated through nonequilibrium molecular dynamics with Monte Carlo methods. We have proposed the relationship among the speed, the temperature, the density distribution and the collective diffusion coefficient of particles in a relativistic moving system. It is found that the relativistic speed of the system has no effect on the temperature, but the collective diffusion coefficient decreases to zero as the velocity of the system approaches to the speed of light. The collective diffusion coefficient is modified as D‧ = D(1 ‑w2 c2 )3 2 for satisfying the relativistic circumstances. The present results may contribute to the understanding of the behavior of the particles transport diffusion in a high speed system, as well as enlighten the study of biological metabolism at relativistic high speed situation.

Exact Relativistic `Antigravity' Propulsion

Science.gov (United States)

Felber, Franklin S.

2006-01-01

The Schwarzschild solution is used to find the exact relativistic motion of a payload in the gravitational field of a mass moving with constant velocity. At radial approach or recession speeds faster than 3-1/2 times the speed of light, even a small mass gravitationally repels a payload. At relativistic speeds, a suitable mass can quickly propel a heavy payload from rest nearly to the speed of light with negligible stresses on the payload.

Relativistic Boltzmann theory for a plasma

International Nuclear Information System (INIS)

Erkelens, H. van.

1984-01-01

This thesis gives a self-contained treatment of the relativistic Boltzmann theory for a plasma. Here plasma means any mixture containing electrically charged particles. The relativistic Boltzmann equation is linearized for the case of a plasma. The Chapman-Enskog method is elaborated further for transport phenomena. Linear laws for viscous phenomena are derived. Then the collision term in the Boltzmann theory is dealt with. Using the transport equation, a kinetic theory of wave phenomena is developed and the dissipation of hydromagnetic waves in a relativistic plasma is investigated. In the final chapter, it is demonstrated how the relativistic Boltzmann theory can be applied in cosmology. In doing so, expressions are derived for the electric conductivity of the cosmological plasma in the lepton era, the plasma era and the annihilation era. (Auth.)

Larmor precession and dwell time of a relativistic particle scattered by a rectangular quantum well

CERN Document Server

Li, Z J; Liang, J J; Liang, J Q

2003-01-01

The Larmor precession of a relativistic neutral spin particle in a uniform constant magnetic field confined to the region of a one-dimensional rectangular potential well is investigated. The spin precession serves as a clock to measure the time spent by a quantum particle dwelling at a potential well. With the help of a general spin coherent state it is explicitly shown that the spin precession time is equal to the dwell time in the first-order approximation of the infinitesimal field limit. The comparison of the time in a potential well with that in free space shows apparent superluminality.

Relativistic theory for syntonization of clocks in the vicinity of the Earth

Science.gov (United States)

Wolf, Peter; Petit, G.

1995-01-01

A well known prediction of Einstein's general theory of relativity states that two ideal clocks that move with a relative velocity, and are submitted to different gravitational fields will, in general, be observed to run at different rates. Similarly the rate of a clock with respect to the coordinate time of some spacetime reference system is dependent on the velocity of the clock in that reference system and on the gravitational fields it is submitted to. For the syntonization of clocks and the realization of coordinate times (like TAI) this rate shift has to be taken into account at an accuracy level which should be below the frequency stability of the clocks in question, i.e. all terms that are larger than the instability of the clocks should be corrected for. We present a theory for the calculation of the relativistic rate shift for clocks in the vicinity of the Earth, including all terms larger than one part in 10(exp 18). This, together with previous work on clock synchronization (Petit & Wolf 1993, 1994), amounts to a complete relativistic theory for the realization of coordinate time scales at picosecond synchronization and 10(exp -18) syntonization accuracy, which should be sufficient to accommodate future developments in time transfer and clock technology.

Relativistic effects in the Thomas--Fermi atom

International Nuclear Information System (INIS)

Waber, J.T.; Canfield, J.M.

1975-01-01

Two methods of applying relativistic corrections to the Thomas--Fermi atom are considered, and numerical calculations are discussed. Radial charge distributions calculated from a relativistic Thomas--Fermi equation agree in gross form with those from more complicated self-consistent calculations. Energy eigenvalues for mercury, as determined from the relativistic Thomas--Fermi solution, are compared with other calculated and experimental values

Relativistic klystron research for linear colliders

International Nuclear Information System (INIS)

Allen, M.A.; Callin, R.S.; Deruyter, H.; Eppley, K.R.; Fant, K.S.; Fowkes, W.R.; Herrmannsfeldt, W.B.; Hoag, H.A.; Koontz, R.F.; Lavine, T.L.; Lee, T.G.; Loew, G.A.; Miller, R.H.; Morton, P.L.; Palmer, R.B.; Paterson, J.M.; Ruth, R.D.; Schwarz, H.D.; Vlieks, A.E.; Wilson, P.B.

1989-01-01

Relativistic klystrons are being developed as a power source for high gradient accelerator applications which include large linear electron-positron colliders, compact accelerators, and FEL sources. The authors have attained 200 MW peak power at 11.4 GHz from a relativistic klystron, and 140 MV/m longitudinal gradient in a short 11.4 GHz accelerator section. In this paper the authors report on the design of our relativistic klystrons, the results of our experiments so far, and some of our plans for the near future

Relativistic klystron research for linear colliders

International Nuclear Information System (INIS)

Allen, M.A.; Callin, R.S.; Deruyter, H.

1988-09-01

Relativistic klystrons are being developed as a power source for high gradient accelerator applications which include large linear electron-positron colliders, compact accelerators, and FEL sources. We have attained 200 MW peak power at 11.4 GHz from a relativistic klystron, and 140 MV/m longitudinal gradient in a short 11.4 GHz accelerator section. We report here on the design of our relativistic klystrons, the results of our experiments so far, and some of our plans for the near future. 5 refs., 9 figs., 1 tab

Relativistic approach to nuclear structure

International Nuclear Information System (INIS)

Nguyen Van Giai; Bouyssy, A.

1987-03-01

Some recent works related with relativistic models of nuclear structure are briefly reviewed. The Dirac-Hartree-Fock and Dirac-Brueckner-Hartree-Fock are recalled and illustrated by some examples. The problem of isoscalar current and magnetic moments of odd nuclei is discussed. The application of the relativistic model to the nuclear response function is examined

Sex education and ideals

NARCIS (Netherlands)

de Ruyter, D.J.; Spiecker, B.

2008-01-01

This article argues that sex education should include sexual ideals. Sexual ideals are divided into sexual ideals in the strict sense and sexual ideals in the broad sense. It is argued that ideals that refer to the context that is deemed to be most ideal for the gratification of sexual ideals in the

Relativistic heavy-ion physics

CERN Document Server

Herrera Corral, G

2010-01-01

The study of relativistic heavy-ion collisions is an important part of the LHC research programme at CERN. This emerging field of research focuses on the study of matter under extreme conditions of temperature, density, and pressure. Here we present an introduction to the general aspects of relativistic heavy-ion physics. Afterwards we give an overview of the accelerator facility at CERN and then a quick look at the ALICE project as a dedicated experiment for heavy-ion collisions.

Relativistic theories of materials

CERN Document Server

Bressan, Aldo

1978-01-01

The theory of relativity was created in 1905 to solve a problem concerning electromagnetic fields. That solution was reached by means of profound changes in fundamental concepts and ideas that considerably affected the whole of physics. Moreover, when Einstein took gravitation into account, he was forced to develop radical changes also in our space-time concepts (1916). Relativistic works on heat, thermodynamics, and elasticity appeared as early as 1911. However, general theories having a thermodynamic basis, including heat conduction and constitutive equations, did not appear in general relativity until about 1955 for fluids and appeared only after 1960 for elastic or more general finitely deformed materials. These theories dealt with materials with memory, and in this connection some relativistic versions of the principle of material indifference were considered. Even more recently, relativistic theories incorporating finite deformations for polarizable and magnetizable materials and those in which couple s...

Relativistic dynamics without conservation laws

OpenAIRE

Rothenstein, Bernhard; Popescu, Stefan

2006-01-01

We show that relativistic dynamics can be approached without using conservation laws (conservation of momentum, of energy and of the centre of mass). Our approach avoids collisions that are not easy to teach without mnemonic aids. The derivations are based on the principle of relativity and on its direct consequence, the addition law of relativistic velocities.

Time Operator in Relativistic Quantum Mechanics

Science.gov (United States)

Khorasani, Sina

2017-07-01

It is first shown that the Dirac’s equation in a relativistic frame could be modified to allow discrete time, in agreement to a recently published upper bound. Next, an exact self-adjoint 4 × 4 relativistic time operator for spin-1/2 particles is found and the time eigenstates for the non-relativistic case are obtained and discussed. Results confirm the quantum mechanical speculation that particles can indeed occupy negative energy levels with vanishingly small but non-zero probablity, contrary to the general expectation from classical physics. Hence, Wolfgang Pauli’s objection regarding the existence of a self-adjoint time operator is fully resolved. It is shown that using the time operator, a bosonic field referred here to as energons may be created, whose number state representations in non-relativistic momentum space can be explicitly found.

Relativistic klystron research for linear colliders

International Nuclear Information System (INIS)

Allen, M.A.; Callin, R.S.; Deruyter, H.; Eppley, K.R.; Fant, K.S.; Fowkes, W.R.; Herrmannesfeldt, W.B.; Higo, T.; Hoag, H.A.; Koontz, R.F.; Lavine, T.L.; Lee, T.G.; Loew, G.A.; Miller, R.H.; Morton, P.L.; Palmer, R.B.; Paterson, J.M.; Ruth, R.D.; Schwarz, H.D.; Takeuchi, Y.; Vlieks, A.E.; Wang, J.W.; Wilson, P.B.; Hopkins, D.B.; Sessler, A.M.; Ryne, R.D.; Westenskow, G.A.; Yu, S.S.

1989-01-01

Relativistic klystrons are being developed as a power source for high gradient accelerator applications which include large linear electron-positron colliders, compact accelerators, and FEL sources. The authors have attained 200MW peak power at 11.4 GHz from a relativistic klystron, and 140 MV/m longitudinal gradient in a short 11.4 GHz accelerator section. They report here on the design of our relativistic klystrons, the results of our experiments so far, and some of our plans for the near future. 5 refs., 9 figs., 1 tab

Relativistic Theory of Few Body Systems

Energy Technology Data Exchange (ETDEWEB)

Franz Gross

2002-11-01

Very significant advances have been made in the relativistic theory of few body systems since I visited Peter Sauer and his group in Hannover in 1983. This talk provides an opportunity to review the progress in this field since then. Different methods for the relativistic calculation of few nucleon systems are briefly described. As an example, seven relativistic calculations of the deuteron elastic structure functions, A, B, and T{sub 20}, are compared. The covariant SPECTATOR {copyright} theory, among the more successful and complete of these methods, is described in more detail.

Relativistic few body calculations

International Nuclear Information System (INIS)

Gross, F.

1988-01-01

A modern treatment of the nuclear few-body problem must take into account both the quark structure of baryons and mesons, which should be important at short range, and the relativistic exchange of mesons, which describes the long range, peripheral interactions. A way to model both of these aspects is described. The long range, peripheral interactions are calculated using the spectator model, a general approach in which the spectators to nucleon interactions are put on their mass-shell. Recent numerical results for a relativistic OBE model of the NN interaction, obtained by solving a relativistic equation with one-particle on mass-shell, will be presented and discussed. Two meson exchange models, one with only four mesons (π,σ,/rho/,ω) but with a 25% admixture of γ 5 coupling for the pion, and a second with six mesons (π,σ,/rho/,ω,δ,/eta/) but pure γ 5 γ/sup μ/ pion coupling, are shown to give very good quantitative fits to the NN scattering phase shifts below 400 MeV, and also a good description of the /rvec p/ 40 Ca elastic scattering observables. Applications of this model to electromagnetic interactions of the two body system, with emphasis on the determination of relativistic current operators consistent with the dynamics and the exact treatment of current conservation in the presence of phenomenological form factors, will be described. 18 refs., 8 figs

Relativistic Gas Drag on Dust Grains and Implications

Energy Technology Data Exchange (ETDEWEB)

Hoang, Thiem, E-mail: thiemhoang@kasi.re.kr [Korea Astronomy and Space Science Institute, Daejeon 34055 (Korea, Republic of); Korea University of Science and Technology, Daejeon, 34113 (Korea, Republic of)

2017-09-20

We study the drag force on grains moving at relativistic velocities through interstellar gas and explore its application. First, we derive a new analytical formula of the drag force at high energies and find that it is significantly reduced compared to the classical model. Second, we apply the obtained drag force to calculate the terminal velocities of interstellar grains by strong radiation sources such as supernovae and active galactic nuclei (AGNs). We find that grains can be accelerated to relativistic velocities by very luminous AGNs. We then quantify the deceleration of relativistic spacecraft proposed by the Breakthrough Starshot initiative due to gas drag on a relativistic lightsail. We find that the spacecraft’s decrease in speed is negligible because of the suppression of gas drag at relativistic velocities, suggesting that the lightsail may be open for communication during its journey to α Centauri without causing a considerable delay. Finally, we show that the damage to relativistic thin lightsails by interstellar dust is a minor effect.

Relativistic heavy ion collisions

International Nuclear Information System (INIS)

Barz, H.W.; Kaempfer, B.; Schulz, H.

1984-12-01

An elementary introduction is given into the scenario of relativistic heavy ion collisions. It deals with relativistic kinematics and estimates of energy densities, extrapolations of the present knowledge of hadron-hadron and hadron-nuleus to nucleus-nucleus collisions, the properties of the quark-gluon plasma and the formation of the plasma and possible experimental signatures. Comments are made on a cosmic ray experiment which could be interpreted as a first indication of the quark-gluon phase of the matter. (author)

Thermodynamic laws and equipartition theorem in relativistic Brownian motion.

Science.gov (United States)

Koide, T; Kodama, T

2011-06-01

We extend the stochastic energetics to a relativistic system. The thermodynamic laws and equipartition theorem are discussed for a relativistic Brownian particle and the first and the second law of thermodynamics in this formalism are derived. The relation between the relativistic equipartition relation and the rate of heat transfer is discussed in the relativistic case together with the nature of the noise term.

Relativistic quantum similarities in atoms in position and momentum spaces

International Nuclear Information System (INIS)

Maldonado, P.; Sarsa, A.; Buendia, E.; Galvez, F.J.

2011-01-01

A study of different quantum similarity measures and their corresponding quantum similarity indices is carried out for the atoms from H to Lr (Z=1-103). Relativistic effects in both position and momentum spaces have been studied by comparing the relativistic values to the non-relativistic ones. We have used the atomic electron density in both position and momentum spaces obtained within relativistic and non-relativistic numerical-parameterized optimized effective potential approximations. -- Highlights: → Quantum similarity measures and indices in electronic structure of atoms. → Position and momentum electronic densities. → Similarity of relativistic and non-relativistic densities. → Similarity of core and valence regions of different atoms. → Dependence with Z along the Periodic Table.

Relativistic positioning in Schwarzschild space-time

International Nuclear Information System (INIS)

Puchades, Neus; Sáez, Diego

2015-01-01

In the Schwarzschild space-time created by an idealized static spherically symmetric Earth, two approaches -based on relativistic positioning- may be used to estimate the user position from the proper times broadcast by four satellites. In the first approach, satellites move in the Schwarzschild space-time and the photons emitted by the satellites follow null geodesics of the Minkowski space-time asymptotic to the Schwarzschild geometry. This assumption leads to positioning errors since the photon world lines are not geodesics of any Minkowski geometry. In the second approach -the most coherent one- satellites and photons move in the Schwarzschild space-time. This approach is a first order one in the dimensionless parameter GM/R (with the speed of light c=1). The two approaches give different inertial coordinates for a given user. The differences are estimated and appropriately represented for users located inside a great region surrounding Earth. The resulting values (errors) are small enough to justify the use of the first approach, which is the simplest and the most manageable one. The satellite evolution mimics that of the GALILEO global navigation satellite system. (paper)

Kinetic analysis of thermally relativistic flow with dissipation

International Nuclear Information System (INIS)

Yano, Ryosuke; Suzuki, Kojiro

2011-01-01

Nonequilibrium flow of thermally relativistic matter with dissipation is considered in the framework of the relativistic kinetic theory. As an object of the analysis, the supersonic rarefied flow of thermally relativistic matter around the triangle prism is analyzed using the Anderson-Witting model. Obtained numerical results indicate that the flow field changes in accordance with the flow velocity and temperature of the uniform flow owing to both effects derived from the Lorentz contraction and thermally relativistic effects, even when the Mach number of the uniform flow is fixed. The profiles of the heat flux along the stagnation streamline can be approximated on the basis of the relativistic Navier-Stokes-Fourier (NSF) law except for a strong nonequilibrium regime such as the middle of the shock wave and the vicinity of the wall, whereas the profile of the heat flux behind the triangle prism cannot be approximated on the basis of the relativistic NSF law owing to rarefied effects via the expansion behind the triangle prism. Additionally, the heat flux via the gradient of the static pressure is non-negligible owing to thermally relativistic effects. The profile of the dynamic pressure is different from that approximated on the basis of the NSF law, which is obtained by the Eckart decomposition. Finally, variations of convections of the mass and momentum owing to the effects derived from the Lorentz contraction and thermally relativistic effects are numerically confirmed.

About the influence of phase mixing process and current neutralization on the resistive sausage instability dynamics of a relativistic electron beam

Science.gov (United States)

Kolesnikov, E. K.; Manuilov, A. S.; Petrov, V. S.; Zelensky, A. G.

2018-05-01

The resistive sausage instability of the relativistic electron beam in dense gas-plasma medium in the case of the generation of equilibrium return plasma current is investigated. In this situation the eigenvalue equation of this instability is obtained. The stabilizing and destabilizing effects of the phase mixing and generation of the return plasma current respectively have been shown.

Effects of a neutral current on the neutrino bremsstrahlung

International Nuclear Information System (INIS)

Ju, I.

1977-01-01

The energy-loss rate due to the neutrino bremsstrahlung from relativistic electrons in a dense matter such as a star is calculated in the framework of Weinberg's unified theory of weak and electromagnetic interactions by using the method of neutrino-energy expansion. The momentum-transfer integration, though complicated, can be carried out analytically, but the subsequent two electron integrals, called the distribution integrals, are helpless and do not allow any further analytic calculation. In order to avoid this difficulty, we set up a set of variables whose integration is simple enough to be expanded in series. It turns out that this series becomes a power series in the Fermi energy inverse after the distribution integrals. This enables us to keep only the leading terms, greatly simplifying the final result. Thus in principle we will be able to calculate arbitrary higher-order terms, even though most of them require prohibitively tedious labor. We carry out the next-higher-order calculations to find that the correction to the lowest-order contribution is within 5%. This confirms the earlier calculations of Festa and Ruderman, even though the two approaches are quite different: the neutrino-bremsstrahlung energy-loss rate is proportional to T 6 and independent of the density at extremely relativistic degenerate regions. We find that the asymptotic expression for the energy-loss rate is of the form A (β) + (rho/μ/sub e/) -1 / 3 kTB (β). The most striking effect of the neutral current is the muon-neutrino emission. The ratio of the energy-loss rate in Weinberg's theory to that in the conventional theory is 1/2 + 4 sin 4 theta/sub W/ at the extreme relativistic-degenerate and nondegenerate-nonrelativistic regions

Theoretical study of the relativistic molecular rotational g-tensor

International Nuclear Information System (INIS)

Aucar, I. Agustín; Gomez, Sergio S.; Giribet, Claudia G.; Ruiz de Azúa, Martín C.

2014-01-01

An original formulation of the relativistic molecular rotational g-tensor valid for heavy atom containing compounds is presented. In such formulation, the relevant terms of a molecular Hamiltonian for non-relativistic nuclei and relativistic electrons in the laboratory system are considered. Terms linear and bilinear in the nuclear rotation angular momentum and an external uniform magnetic field are considered within first and second order (relativistic) perturbation theory to obtain the rotational g-tensor. Relativistic effects are further analyzed by carrying out the linear response within the elimination of the small component expansion. Quantitative results for model systems HX (X=F, Cl, Br, I), XF (X=Cl, Br, I), and YH + (Y=Ne, Ar, Kr, Xe, Rn) are obtained both at the RPA and density functional theory levels of approximation. Relativistic effects are shown to be small for this molecular property. The relation between the rotational g-tensor and susceptibility tensor which is valid in the non-relativistic theory does not hold within the relativistic framework, and differences between both molecular parameters are analyzed for the model systems under study. It is found that the non-relativistic relation remains valid within 2% even for the heavy HI, IF, and XeH + systems. Only for the sixth-row Rn atom a significant deviation of this relation is found

Theoretical study of the relativistic molecular rotational g-tensor

Energy Technology Data Exchange (ETDEWEB)

Aucar, I. Agustín, E-mail: agustin.aucar@conicet.gov.ar; Gomez, Sergio S., E-mail: ssgomez@exa.unne.edu.ar [Institute for Modeling and Technological Innovation, IMIT (CONICET-UNNE) and Faculty of Exact and Natural Sciences, Northeastern University of Argentina, Avenida Libertad 5400, W3404AAS Corrientes (Argentina); Giribet, Claudia G.; Ruiz de Azúa, Martín C. [Physics Department, Faculty of Exact and Natural Sciences, University of Buenos Aires and IFIBA CONICET, Ciudad Universitaria, Pab. I, 1428 Buenos Aires (Argentina)

2014-11-21

An original formulation of the relativistic molecular rotational g-tensor valid for heavy atom containing compounds is presented. In such formulation, the relevant terms of a molecular Hamiltonian for non-relativistic nuclei and relativistic electrons in the laboratory system are considered. Terms linear and bilinear in the nuclear rotation angular momentum and an external uniform magnetic field are considered within first and second order (relativistic) perturbation theory to obtain the rotational g-tensor. Relativistic effects are further analyzed by carrying out the linear response within the elimination of the small component expansion. Quantitative results for model systems HX (X=F, Cl, Br, I), XF (X=Cl, Br, I), and YH{sup +} (Y=Ne, Ar, Kr, Xe, Rn) are obtained both at the RPA and density functional theory levels of approximation. Relativistic effects are shown to be small for this molecular property. The relation between the rotational g-tensor and susceptibility tensor which is valid in the non-relativistic theory does not hold within the relativistic framework, and differences between both molecular parameters are analyzed for the model systems under study. It is found that the non-relativistic relation remains valid within 2% even for the heavy HI, IF, and XeH{sup +} systems. Only for the sixth-row Rn atom a significant deviation of this relation is found.

Loading relativistic Maxwell distributions in particle simulations

Energy Technology Data Exchange (ETDEWEB)

Zenitani, Seiji, E-mail: seiji.zenitani@nao.ac.jp [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

2015-04-15

Numerical algorithms to load relativistic Maxwell distributions in particle-in-cell (PIC) and Monte-Carlo simulations are presented. For stationary relativistic Maxwellian, the inverse transform method and the Sobol algorithm are reviewed. To boost particles to obtain relativistic shifted-Maxwellian, two rejection methods are proposed in a physically transparent manner. Their acceptance efficiencies are ≈50% for generic cases and 100% for symmetric distributions. They can be combined with arbitrary base algorithms.

Loading relativistic Maxwell distributions in particle simulations

International Nuclear Information System (INIS)

Zenitani, Seiji

2015-01-01

Numerical algorithms to load relativistic Maxwell distributions in particle-in-cell (PIC) and Monte-Carlo simulations are presented. For stationary relativistic Maxwellian, the inverse transform method and the Sobol algorithm are reviewed. To boost particles to obtain relativistic shifted-Maxwellian, two rejection methods are proposed in a physically transparent manner. Their acceptance efficiencies are ≈50% for generic cases and 100% for symmetric distributions. They can be combined with arbitrary base algorithms

The de Sitter relativistic top theory

International Nuclear Information System (INIS)

Armenta, J.; Nieto, J.A.

2005-01-01

We discuss the relativistic top theory from the point of view of the de Sitter (or anti-de Sitter) group. Our treatment rests on the Hanson-Regge spherical relativistic top Lagrangian formulation. We propose an alternative method for studying spinning objects via Kaluza-Klein theory. In particular, we derive the relativistic top equations of motion starting with the geodesic equation for a point particle in 4+N dimensions. We compare our approach with Fukuyama's formulation of spinning objects, which is also based on Kaluza-Klein theory. We also report a generalization of our approach to a 4+N+D dimensional theory

Biquaternions and relativistic kinematics

International Nuclear Information System (INIS)

Bogush, A.A.; Kurochkin, Yu.A.; Fedorov, F.I.

1979-01-01

The problems concerning the use of quaternion interpretation of the Lorentz group vector parametrization are considered for solving relativistic kinematics problems. A vector theory convenient for describing the characteristic features of the Lobachevsky space is suggested. The kinematics of elementary particle scattering is investigated on the basis of this theory. A synthesis of vector parametrization and of quaternion calculation has been shown to lead to natural formulation of the theory of vectors in the three-dimensional Lobachevsky space, realized on mass hyperboloids of relativistic particles

Canonical formalism for relativistic dynamics

International Nuclear Information System (INIS)

Penafiel-Nava, V.M.

1982-01-01

The possibility of a canonical formalism appropriate for a dynamical theory of isolated relativistic multiparticle systems involving scalar interactions is studied. It is shown that a single time-parameter structure satisfying the requirements of Poincare invariance and simultaneity of the constituents (global tranversality) can not be derived from a homogeneous Lagrangian. The dynamics is deduced initially from a non-homogeneous but singular Lagrangian designed to accommodate the global tranversality constraints with the equaltime plane associated to the total momentum of the system. An equivalent standard Lagrangian is used to generalize the parametrization procedure which is referred to an arbitrary geodesic in Minkowski space. The equations of motion and the definition of center of momentum are invariant with respect to the choice of geodesic and the entire formalism becomes separable. In the original 8N-dimensional phase-space, the symmetries of the Lagrangian give rise to a canonical realization of a fifteen-generator Lie algebra which is projected in the 6N dimensional hypersurface of dynamical motions. The time-component of the total momentum is thus reduced to a neutral element and the canonical Hamiltonian survives as the only generator for time-translations so that the no-interaction theorem becomes inapplicable

Liouville equation of relativistic charged fermion

International Nuclear Information System (INIS)

Wang Renchuan; Zhu Dongpei; Huang Zhuoran; Ko Che-ming

1991-01-01

As a form of density martrix, the Wigner function is the distribution in quantum phase space. It is a 2 X 2 matrix function when one uses it to describe the non-relativistic fermion. While describing the relativistic fermion, it is usually represented by 4 x 4 matrix function. In this paper authors obtain a Wigner function for the relativistic fermion in the form of 2 x 2 matrix, and the Liouville equation satisfied by the Wigner function. this equivalent to the Dirac equation of changed fermion in QED. The equation is also equivalent to the Dirac equation in the Walecka model applied to the intermediate energy nuclear collision while the nucleon is coupled to the vector meson only (or taking mean field approximation for the scalar meson). Authors prove that the 2 x 2 Wigner function completely describes the quantum system just the same as the relativistic fermion wave function. All the information about the observables can be obtained with above Wigner function

An energy principle for two-dimensional collisionless relativistic plasmas

International Nuclear Information System (INIS)

Otto, A.; Schindler, K.

1984-01-01

Using relativistic Vlasov theory an energy principle for two-dimensional plasmas is derived, which provides a sufficient and necessary criterion for the stability of relativistic plasma equilibria. This energy principle includes charge separating effects since the exact Poisson equation was taken into consideration. Applying the variational principle to the case of the relativistic plane plasma sheet, the same marginal wave length is found as in the non-relativistic case. (author)

Relativistic neoclassical transport coefficients with momentum correction

International Nuclear Information System (INIS)

Marushchenko, I.; Azarenkov, N.A.

2016-01-01

The parallel momentum correction technique is generalized for relativistic approach. It is required for proper calculation of the parallel neoclassical flows and, in particular, for the bootstrap current at fusion temperatures. It is shown that the obtained system of linear algebraic equations for parallel fluxes can be solved directly without calculation of the distribution function if the relativistic mono-energetic transport coefficients are already known. The first relativistic correction terms for Braginskii matrix coefficients are calculated.

Penetration of relativistic heavy ions through matter

International Nuclear Information System (INIS)

Scheidenberger, C.; Geissel, H.

1997-07-01

New heavy-ion accelerators covering the relativistic and ultra-relativistic energy regime allow to study atomic collisions with bare and few-electron projectiles. High-resolution magnetic spectrometers are used for precise stopping-power and energy-loss straggling measurements. Refined theories beyond the Born approximation have been developed and are confirmed by experiments. This paper summarizes the large progress in the understanding of relativistic heavy-ion penetration through matter, which has been achieved in the last few years. (orig.)

Relativistic Kinematics

OpenAIRE

Sahoo, Raghunath

2016-01-01

This lecture note covers Relativistic Kinematics, which is very useful for the beginners in the field of high-energy physics. A very practical approach has been taken, which answers "why and how" of the kinematics useful for students working in the related areas.

Relativistic klystrons

International Nuclear Information System (INIS)

Allen, M.A.; Azuma, O.; Callin, R.S.

1989-03-01

Experimental work is underway by a SLAC-LLNL-LBL collaboration to investigate the feasibility of using relativistic klystrons as a power source for future high gradient accelerators. Two different relativistic klystron configurations have been built and tested to date: a high grain multicavity klystron at 11.4 GHz and a low gain two cavity subharmonic buncher driven at 5.7 GHz. In both configurations power is extracted at 11.4 GHz. In order to understand the basic physics issues involved in extracting RF from a high power beam, we have used both a single resonant cavity and a multi-cell traveling wave structure for energy extraction. We have learned how to overcome our previously reported problem of high power RF pulse shortening, and have achieved peak RF power levels of 170 MW with the RF pulse of the same duration as the beam current pulse. 6 refs., 3 figs., 3 tabs

Chaos and maps in relativistic rynamical systems

Directory of Open Access Journals (Sweden)

L. P. Horwitz

2000-01-01

Full Text Available The basic work of Zaslavskii et al showed that the classical non-relativistic electromagnetically kicked oscillator can be cast into the form of an iterative map on the phase space; the resulting evolution contains a stochastic flow to unbounded energy. Subsequent studies have formulated the problem in terms of a relativistic charged particle in interaction with the electromagnetic field. We review the structure of the covariant Lorentz force used to study this problem. We show that the Lorentz force equation can be derived as well from the manifestly covariant mechanics of Stueckelberg in the presence of a standard Maxwell field, establishing a connection between these equations and mass shell constraints. We argue that these relativistic generalizations of the problem are intrinsically inaccurate due to an inconsistency in the structure of the relativistic Lorentz force, and show that a reformulation of the relativistic problem, permitting variations (classically in both the particle mass and the effective “mass” of the interacting electromagnetic field, provides a consistent system of classical equations for describing such processes.

A Primer to Relativistic MOND Theory

NARCIS (Netherlands)

Bekenstein, J.D..; Sanders, R.H.

2005-01-01

Abstract: We first review the nonrelativistic lagrangian theory as a framework for the MOND equation. Obstructions to a relativistic version of it are discussed leading up to TeVeS, a relativistic tensor-vector-scalar field theory which displays both MOND and Newtonian limits. The whys for its

Relativistic Quantum Transport in Graphene Systems

Science.gov (United States)

2015-07-09

dimensional Dirac material systems. 2 List of Publications 1. X. Ni, L. Huang, Y.-C. Lai, and L. M. Pecora, “Effect of chaos on relativistic quantum...development of relativistic quantum devices based on graphene or alternative two-dimensional Dirac material systems. In the project period, we studied

Relativistic astrophysics and theory of gravity

International Nuclear Information System (INIS)

Zel'dovich, Ya.B.

1982-01-01

A brief historical review of the development of astrophysical science in the State Astrophysical Institute named after Shternberg (SAISh) has been given in a popular form. The main directions of the SAISh astrophysical investigations have been presented: relativistic theory of gravity, relativistic astrophysics of interplanetary medium and cosmology

Relativistic MHD simulations of stellar core collapse and magnetars

Energy Technology Data Exchange (ETDEWEB)

Font, Jose A; Gabler, Michael [Departamento de AstronomIa y Astrofisica, Universitat de Valencia, 46100 Burjassot (Valencia) (Spain); Cerda-Duran, Pablo; Mueller, Ewald [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching (Germany); Stergioulas, Nikolaos, E-mail: j.antonio.font@uv.es [Department of Physics, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece)

2011-02-01

We present results from simulations of magneto-rotational stellar core collapse along with Alfven oscillations in magnetars. These simulations are performed with the CoCoA/CoCoNuT code, which is able to handle ideal MHD flows in dynamical spacetimes in general relativity. Our core collapse simulations highlight the importance of genuine magnetic effects, like the magneto-rotational instability, for the dynamics of the flow. For the modelling of magnetars we use the anelastic approximation to general relativistic MHD, which allows for an effective suppression of fluid modes and an accurate description of Alfven waves. We further compute Alfven oscillation frequencies along individual magnetic field lines with a semi-analytic approach. Our work confirms previous results based on perturbative approaches regarding the existence of two families of quasi-periodic oscillations (QPOs), with harmonics at integer multiples of the fundamental frequency. Additional material is presented in the accompanying contribution by Gabler et al (2010b) in these proceedings.

Characterization of human monoclonal antibodies that neutralize multiple poliovirus serotypes.

Science.gov (United States)

Puligedda, Rama Devudu; Kouiavskaia, Diana; Al-Saleem, Fetweh H; Kattala, Chandana Devi; Nabi, Usman; Yaqoob, Hamid; Bhagavathula, V Sandeep; Sharma, Rashmi; Chumakov, Konstantin; Dessain, Scott K

2017-10-04

Following the eradication of wild poliovirus (PV), achieving and maintaining a polio-free status will require eliminating potentially pathogenic PV strains derived from the oral attenuated vaccine. For this purpose, a combination of non-cross-resistant drugs, such as small molecules and neutralizing monoclonal antibodies (mAbs), may be ideal. We previously isolated chimpanzee and human mAbs capable of neutralizing multiple PV types (cross-neutralization). Here, we describe three additional human mAbs that neutralize types 1 and 2 PV and one mAb that neutralizes all three types. Most bind conformational epitopes and have unusually long heavy chain complementarity determining 3 domains (HC CDR3). We assessed the ability of the mAbs to neutralize A12 escape mutant PV strains, and found that the neutralizing activities of the mAbs were disrupted by different amino acid substitutions. Competitive binding studies further suggested that the specific mAb:PV interactions that enable cross-neutralization differ among mAbs and serotypes. All of the cloned mAbs bind PV in the vicinity of the "canyon", a circular depression around the 5-fold axis of symmetry through which PV recognizes its cellular receptor. We were unable to generate escape mutants to two of the mAbs, suggesting that their epitopes are important for the PV life cycle. These data indicate that PV cross-neutralization involves binding to highly conserved structures within the canyon that binds to the cellular receptor. These may be facilitated by the long HC CDR3 domains, which may adopt alternative binding configurations. We propose that the human and chimpanzee mAbs described here could have potential as anti-PV therapeutics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Non-relativistic Bondi-Metzner-Sachs algebra

Science.gov (United States)

Batlle, Carles; Delmastro, Diego; Gomis, Joaquim

2017-09-01

We construct two possible candidates for non-relativistic bms4 algebra in four space-time dimensions by contracting the original relativistic bms4 algebra. bms4 algebra is infinite-dimensional and it contains the generators of the Poincaré algebra, together with the so-called super-translations. Similarly, the proposed nrbms4 algebras can be regarded as two infinite-dimensional extensions of the Bargmann algebra. We also study a canonical realization of one of these algebras in terms of the Fourier modes of a free Schrödinger field, mimicking the canonical realization of relativistic bms4 algebra using a free Klein-Gordon field.

Whispering gallery effect in relativistic optics

Science.gov (United States)

Abe, Y.; Law, K. F. F.; Korneev, Ph.; Fujioka, S.; Kojima, S.; Lee, S.-H.; Sakata, S.; Matsuo, K.; Oshima, A.; Morace, A.; Arikawa, Y.; Yogo, A.; Nakai, M.; Norimatsu, T.; d'Humières, E.; Santos, J. J.; Kondo, K.; Sunahara, A.; Gus'kov, S.; Tikhonchuk, V.

2018-03-01

relativistic laser pulse, confined in a cylindrical-like target, under specific conditions may perform multiple scattering along the internal target surface. This results in the confinement of the laser light, leading to a very efficient interaction. The demonstrated propagation of the laser pulse along the curved surface is just yet another example of the "whispering gallery" effect, although nonideal due to laser-plasma coupling. In the relativistic domain its important feature is a gradual intensity decrease, leading to changes in the interaction conditions. The proccess may pronounce itself in plenty of physical phenomena, including very efficient electron acceleration and generation of relativistic magnetized plasma structures.

Buffer-eliminated, charge-neutral epitaxial graphene on oxidized 4H-SiC (0001) surface

International Nuclear Information System (INIS)

Sirikumara, Hansika I.; Jayasekera, Thushari

2016-01-01

Buffer-eliminated, charge-neutral epitaxial graphene (EG) is important to enhance its potential in device applications. Using the first principles Density Functional Theory calculations, we investigated the effect of oxidation on the electronic and structural properties of EG on 4H-SiC (0001) surface. Our investigation reveals that the buffer layer decouples from the substrate in the presence of both silicate and silicon oxy-nitride at the interface, and the resultant monolayer EG is charge-neutral in both cases. The interface at 4H-SiC/silicate/EG is characterized by surface dangling electrons, which opens up another route for further engineering EG on 4H-SiC. Dangling electron-free 4H-SiC/silicon oxy-nitride/EG is ideal for achieving charge-neutral EG.

Compact toroidal energy storage device with relativistically densified electrons through the use of travelling magnetic waves

International Nuclear Information System (INIS)

Peter, W.; Faehl, R.J.

1983-01-01

A new concept for a small compact multimegajoule energy storage device utilizing relativistically densified electron beam circulating in a torus is presented. The electron cloud is produced through inductive charge injection by a travelling magnetic wave circulating the torus. Parameters are given for two representative toroidal energy storage devices, consisting of 1 m and 32 m in radius respectively, which could store more than 4 x 10 17 electrons and 30' MJ in energy. The concept utilizes the idea that large electric and magnetic fields can be produced by a partially space-charge neutralized intense relativistic electron beam which could become many orders of magnitude greater than the externally applied field confining the beam. In the present approach, the electron cloud densification can be achieved gradually by permitting multiple traversals of the magnetic wave around the torus. The magnetic mirror force acts on the orbital magnetic electron dipole moment and completely penetrates the entire electron cloud. As the electrons gain relativistic energies, the beam can be continuously densified at the front of the travelling wave, where the magnetic field is rising with time. The use of travelling magnetic wave to accelerate an electron cloud and the use of large electric field at the thusly accelerated cloud form the basis for a high beam intensity and hence high energy storage. Technical considerations and several potential applications, which include the driving of a powerful gyrotron, are discussed

Relativistic quantum mechanics and introduction to field theory

Energy Technology Data Exchange (ETDEWEB)

Yndurain, F.J. [Universidad Autonoma de Madrid (Spain). Dept. de Fisica Teorica

1996-12-01

The following topics were dealt with: relativistic transformations, the Lorentz group, Klein-Gordon equation, spinless particles, spin 1/2 particles, Dirac particle in a potential, massive spin 1 particles, massless spin 1 particles, relativistic collisions, S matrix, cross sections, decay rates, partial wave analysis, electromagnetic field quantization, interaction of radiation with matter, interactions in quantum field theory and relativistic interactions with classical sources.

Relativistic quantum mechanics and introduction to field theory

International Nuclear Information System (INIS)

Yndurain, F.J.

1996-01-01

The following topics were dealt with: relativistic transformations, the Lorentz group, Klein-Gordon equation, spinless particles, spin 1/2 particles, Dirac particle in a potential, massive spin 1 particles, massless spin 1 particles, relativistic collisions, S matrix, cross sections, decay rates, partial wave analysis, electromagnetic field quantization, interaction of radiation with matter, interactions in quantum field theory and relativistic interactions with classical sources

Rayleigh scattering of x-ray and {gamma}-ray by 1s and 2s electrons in ions and neutral atoms

Energy Technology Data Exchange (ETDEWEB)

Costescu, A; Karim, K; Stoica, C [Department of Physics, University of Bucharest, MG11, Bucharest-Magurele 077125 (Romania); Moldovan, M [Department of Physics, UMF Targu Mures, Targu Mures 540142 (Romania); Spanulescu, S, E-mail: severspa2004@yahoo.com [Department of Physics, Hyperion University of Bucharest, Bucharest 030629 (Romania)

2011-02-28

Using the Coulomb-Green function method and considering the nonrelativistic limit for the two-photon S-matrix element, the right nonrelativistic 2s Rayleigh scattering amplitudes are obtained. Our result takes into account all multipoles, retardation and relativistic kinematics contributions, and the old dipole approximation result of Costescu is retrieved as a limit case. The total photoeffect cross-section which is related to the imaginary part of the Rayleigh forward scattering amplitude through the optical theorem is also obtained. Our Coulombian formulae are used in the more realistic case of elastic scattering of photons by bound 1s and 2s electrons in ions and neutral atoms. Screening effects are considered in the independent particle approximation through the Hartree-Fock method. The effective charge Z{sub eff} is obtained by fitting the Hartree-Fock charge distribution by a Coulombian one. Good agreement (within 10%) is found when comparing the numerical predictions given by our nonrelativistic formulae with the full relativistic numerical results of Kissel in the case of elastic scattering of photons by 1s and 2s electrons and Scofield [3] in the case of K-shell and 2s subshell photoionization for neutral atoms with 18 {<=} Z {<=} 92 and photon energies {omega} {<=} {alpha}Zm.

A NUMERICAL TREATMENT OF ANISOTROPIC RADIATION FIELDS COUPLED WITH RELATIVISTIC RESISTIVE MAGNETOFLUIDS

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Hiroyuki R. [Center for Computational Astrophysics, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Ohsuga, Ken [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan)

2013-08-01

We develop a numerical scheme for solving fully special relativistic, resistive radiation magnetohydrodynamics. Our code guarantees conservation of total mass, momentum, and energy. The radiation energy density and the radiation flux are consistently updated using the M-1 closure method, which can resolve an anisotropic radiation field, in contrast to the Eddington approximation, as well as the flux-limited diffusion approximation. For the resistive part, we adopt a simple form of Ohm's law. The advection terms are explicitly solved with an approximate Riemann solver, mainly the Harten-Lax-van Leer scheme; the HLLC and HLLD schemes are also solved for some tests. The source terms, which describe the gas-radiation interaction and the magnetic energy dissipation, are implicitly integrated, relaxing the Courant-Friedrichs-Lewy condition even in an optically thick regime or a large magnetic Reynolds number regime. Although we need to invert 4 Multiplication-Sign 4 matrices (for the gas-radiation interaction) and 3 Multiplication-Sign 3 matrices (for the magnetic energy dissipation) at each grid point for implicit integration, they are obtained analytically without preventing massive parallel computing. We show that our code gives reasonable outcomes in numerical tests for ideal magnetohydrodynamics, propagating radiation, and radiation hydrodynamics. We also applied our resistive code to the relativistic Petschek-type magnetic reconnection, revealing the reduction of the reconnection rate via radiation drag.

A NUMERICAL TREATMENT OF ANISOTROPIC RADIATION FIELDS COUPLED WITH RELATIVISTIC RESISTIVE MAGNETOFLUIDS

International Nuclear Information System (INIS)

Takahashi, Hiroyuki R.; Ohsuga, Ken

2013-01-01

We develop a numerical scheme for solving fully special relativistic, resistive radiation magnetohydrodynamics. Our code guarantees conservation of total mass, momentum, and energy. The radiation energy density and the radiation flux are consistently updated using the M-1 closure method, which can resolve an anisotropic radiation field, in contrast to the Eddington approximation, as well as the flux-limited diffusion approximation. For the resistive part, we adopt a simple form of Ohm's law. The advection terms are explicitly solved with an approximate Riemann solver, mainly the Harten-Lax-van Leer scheme; the HLLC and HLLD schemes are also solved for some tests. The source terms, which describe the gas-radiation interaction and the magnetic energy dissipation, are implicitly integrated, relaxing the Courant-Friedrichs-Lewy condition even in an optically thick regime or a large magnetic Reynolds number regime. Although we need to invert 4 × 4 matrices (for the gas-radiation interaction) and 3 × 3 matrices (for the magnetic energy dissipation) at each grid point for implicit integration, they are obtained analytically without preventing massive parallel computing. We show that our code gives reasonable outcomes in numerical tests for ideal magnetohydrodynamics, propagating radiation, and radiation hydrodynamics. We also applied our resistive code to the relativistic Petschek-type magnetic reconnection, revealing the reduction of the reconnection rate via radiation drag

Effects of relativistic small radial component on atomic photoionization cross sections

International Nuclear Information System (INIS)

Liu Xiaobin; Xing Yongzhong; Sun Xiaowei

2008-01-01

The effects of relativistic small radial component on atomic photoionization cross sections have been studied within relativistic average self-consistent field theory. Relativistic effects are relatively unimportant for low photon energy, along with a review of high-energy photoionization the relativistic effects are quite important. The effects of relativistic small radial component on photoionization process should show breakdown when the nuclear finite-size effects is taken into account. The compression of wavefunction into the space near nucleus is so strong in highly charged ions that the electronic radius greatly decreases, and the effects of relativistic small radial component on photoionization cross sections turn to stronger than ordinary atoms. Since relativistic effects are extremely sensitive to the behavior of small radial component, the results are in good agreement with relativistic effects on photoionization cross section. (authors)

Micro-channel plate detector for ultra-fast relativistic electron diffraction

International Nuclear Information System (INIS)

Musumeci, P.; Moody, J.T.; Scoby, C.M.; Gutierrez, M.S.; Bender, H.A.; Hilko, B.; Kruschwitz, C.A.; Wilcox, N.S.

2011-01-01

Using relativistic ultra-short electron beams to obtain single-shot diffraction patterns holds the promise to yield real-time resolution of atomic motion in an easily accessible environment, such as a university laboratory, at a fraction of the cost of fourth-generation X-ray sources. One of the main issues in bringing this technique to full maturity is the development of efficient detector systems to record the diffraction pattern using a few MeV electron beams. Low noise, high spatial resolution, and single-electron detection capability are all characteristics of an ideal detector. In this paper, we compare the performances of a traditional fluorescent phosphor screen with a detection system based on the micro-channel plate (MCP). Since MCPs are typically used with lower energy electron beams, these tests constitute one of the few experimental data points available on the use of these devices with MeV energy beams.

Micro-channel plate detector for ultra-fast relativistic electron diffraction

Energy Technology Data Exchange (ETDEWEB)

Musumeci, P., E-mail: musumeci@physics.ucla.edu [UCLA Department of Physics and Astronomy, 475 Portola Plaza, Los Angeles, CA, 90095-1547 (United States); Moody, J.T.; Scoby, C.M.; Gutierrez, M.S. [UCLA Department of Physics and Astronomy, 475 Portola Plaza, Los Angeles, CA, 90095-1547 (United States); Bender, H.A.; Hilko, B.; Kruschwitz, C.A.; Wilcox, N.S. [National Security Technologies, LLC, Los Alamos Operations, Los Alamos, NM (United States)

2011-05-01

Using relativistic ultra-short electron beams to obtain single-shot diffraction patterns holds the promise to yield real-time resolution of atomic motion in an easily accessible environment, such as a university laboratory, at a fraction of the cost of fourth-generation X-ray sources. One of the main issues in bringing this technique to full maturity is the development of efficient detector systems to record the diffraction pattern using a few MeV electron beams. Low noise, high spatial resolution, and single-electron detection capability are all characteristics of an ideal detector. In this paper, we compare the performances of a traditional fluorescent phosphor screen with a detection system based on the micro-channel plate (MCP). Since MCPs are typically used with lower energy electron beams, these tests constitute one of the few experimental data points available on the use of these devices with MeV energy beams.

Automatic social comparison: Cognitive load facilitates an increase in negative thought accessibility after thin ideal exposure among women.

Science.gov (United States)

Bocage-Barthélémy, Yvana; Chatard, Armand; Jaafari, Nematollah; Tello, Nina; Billieux, Joël; Daveau, Emmanuel; Selimbegović, Leila

2018-01-01

Women are routinely exposed to images of extremely slim female bodies (the thin ideal) in advertisements, even if they do not necessarily pay much attention to these images. We hypothesized that paradoxically, it is precisely in such conditions of low attention that the impact of the social comparison with the thin ideal might be the most pronounced. To test this prediction, one hundred and seventy-three young female participants were exposed to images of the thin ideal or of women's fashion accessories. They were allocated to either a condition of high (memorizing 10 digits) or low cognitive load (memorizing 4 digits). The main dependent measure was implicit: mean recognition latency of negative words, relative to neutral words, as assessed by a lexical decision task. The results showed that thin-ideal exposure did not affect negative word accessibility under low cognitive load but that it increased it under high cognitive load. These findings are consistent with the hypothesis that social comparison with the thin ideal is an automatic process, and contribute to explain why some strategies to prevent negative effects of thin-ideal exposure are inefficient.

The ionisation equation in a relativistic gas

International Nuclear Information System (INIS)

Kichenassamy, S.; Krikorian, R.A.

1983-01-01

By deriving the relativistic form of the ionisation equation for a perfect gas it is shown that the usual Saha equation is valid to 3% for temperatures below one hundred million Kelvin. Beyond 10 9 K, the regular Saha equation is seriously incorrect and a relativistic distribution function for electrons must be taken into account. Approximate forms are derived when only the electrons are relativistic (appropriate up to 10 12 K) and also for the ultrarelativistic case (temperatures greater than 10 15 K). (author)

Effectively semi-relativistic Hamiltonians of nonrelativistic form

International Nuclear Information System (INIS)

Lucha, W.; Schoeberl, F.F.; Moser, M.

1993-12-01

We construct effective Hamiltonians which despite their apparently nonrelativistic form incorporate relativistic effects by involving parameters which depend on the relevant momentum. For some potentials the corresponding energy eigenvalues may be determined analytically. Applied to two-particle bound states, it turns out that in this way a nonrelativistic treatment may indeed be able to simulate relativistic effects. Within the framework of hadron spectroscopy, this lucky circumstance may be an explanation for the sometimes extremely good predictions of nonrelativistic potential models even in relativistic regions. (authors)

Relativistic Astrophysics

International Nuclear Information System (INIS)

Font, J. A.

2015-01-01

The relativistic astrophysics is the field of astrophysics employing the theory of relativity Einstein as physical-mathematical model is to study the universe. This discipline analyzes astronomical contexts in which the laws of classical mechanics of Newton's law of gravitation are not valid. (Author)

Nonequilibrium forces between neutral atoms mediated by a quantum field

International Nuclear Information System (INIS)

Behunin, Ryan O.; Hu, Bei-Lok

2010-01-01

We study forces between two neutral atoms, modeled as three-dimensional harmonic oscillators, arising from mutual influences mediated by an electromagnetic field but not from their direct interactions. We allow as dynamical variables the center-of-mass motion of the atom, its internal degrees of freedom, and the quantum field treated relativistically. We adopt the method of nonequilibrium quantum field theory which can provide a first-principles, systematic, and unified description including the intrinsic and induced dipole fluctuations. The inclusion of self-consistent back-actions makes possible a fully dynamical description of these forces valid for general atom motion. In thermal equilibrium we recover the known forces--London, van der Waals, and Casimir-Polder--between neutral atoms in the long-time limit. We also reproduce a recently reported force between atoms when the system is out of thermal equilibrium at late times. More noteworthy is the discovery of the existence of a type of (or identification of the source of some known) interatomic force which we call the ''entanglement force,'' originating from the quantum correlations of the internal degrees of freedom of entangled atoms.

Relativistic description of directly interacting pions and nucleons

International Nuclear Information System (INIS)

Heller, L.

1976-01-01

The expected magnitudes of the leading relativistic effects on an off-energy-shell T matrix element are estimated using the Bakamjian--Thomas formulation of relativistic potential theory. For pion-nucleon scattering at medium energy, the two largest corrections are expected to result from the use of relativistic relative momenta rather than nonrelativistic values. The importance of additional terms depends upon the detailed behavior of the T matrix

Relativistic and non-relativistic electronic molecular-structure calculations for dimers of 4p-, 5p-, and 6p-block elements.

Science.gov (United States)

Höfener, Sebastian; Ahlrichs, Reinhart; Knecht, Stefan; Visscher, Lucas

2012-12-07

We report results of non-relativistic and two-component relativistic single-reference coupled-cluster with single and double and perturbative triple excitations [CCSD(T)] treatments for the 4p-block dimers Ga(2) to Br(2) , the 5p-block dimers In(2) to I(2) , and their atoms. Extended basis sets up to pentuple zeta are employed and energies extrapolated to the complete basis-set limit. Relativistic and non-relativistic results for the dissociation energy D(e) are in close agreement with each other and previously published data, provided non-relativistic or scalar-relativistic results are corrected for spin-orbit contributions taken from the literature. An exception is Te(2) where theoretical results scatter by 0.085 eV. By virtue of this agreement it is unexpected that comparison with the experimental D(0) or D(e) dissociation energies (zero-point vibrational effects are negligible in this context) reveal errors larger than 0.1 eV for Ga(2), Ge(2), and Sb(2). Only relativistic treatments are presented for the 6p-block cases Tl(2) to At(2). Sufficient agreement with experimental data is found only for Pb(2) and Bi(2), the deviation of the computed and experimental D(0) values for Po(2) is again larger than 0.1 eV. Deviations of 0.1 eV between the computed and experimental D(0) values are a major reason for concern and call for additional investigations in both fields to clarify the situation. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Relativistic ''potential model'' for N-particle systems

International Nuclear Information System (INIS)

Noyes, H.P.

1986-08-01

Neither quantum field theory nor S-Matrix theory have a well defined procedure for going over to an approximation that can be reliably used in non-relativistic models for nuclear physics. We meet the problem here by constructing a finite particle number relativistic scattering theory for (scalar) particles and mesons using integral equations of the Faddeev-Yakubovsky type. Restricted to N particles and one meson, we can go from the relativistic theory to a ''potential theory'' in the integral equation formulation by using boundary states which do not contain the meson asymptotically. The meson-particle input amplitudes contain a pole at the particle mass, and the particle-particle input amplitudes are null. This gives unique definition (numerically calculable) to the particle-particle off-shell amplitude, and hence to the covariant ''scattering potential'' (but not to the noninvariant concept of ''potential energy''). As we have commented before, if we take these scattering amplitudes as iput for relativistic Faddeev equations, the results are identical to those obtained from the same model starting from three particles and one meson. In this paper we explore how far we can extend this relativistic ''potential model'' to higher numbers of particles and mesons. 10 refs

Relativistic Anandan quantum phase and the Aharonov–Casher effect under Lorentz symmetry breaking effects in the cosmic string spacetime

Energy Technology Data Exchange (ETDEWEB)

Bakke, K., E-mail: kbakke@fisica.ufpb.br [Departamento de Física, Universidade Federal da Paraíba, Caixa Postal 5008, 58051-900, João Pessoa-PB (Brazil); Furtado, C., E-mail: furtado@fisica.ufpb.br [Departamento de Física, Universidade Federal da Paraíba, Caixa Postal 5008, 58051-900, João Pessoa-PB (Brazil); Belich, H., E-mail: belichjr@gmail.com [Departamento de Física e Química, Universidade Federal do Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, 29060-900, Vitória, ES (Brazil)

2016-09-15

From the modified Maxwell theory coupled to gravity, we establish a possible scenario of the violation of the Lorentz symmetry and write an effective metric for the cosmic string spacetime. Then, we investigate the arising of an analogue of the Anandan quantum phase for a relativistic Dirac neutral particle with a permanent magnetic dipole moment in the cosmic string spacetime under Lorentz symmetry breaking effects. Besides, we analyse the influence of the effects of the Lorentz symmetry violation and the topology of the defect on the Aharonov–Casher geometric quantum phase in the nonrelativistic limit.

Estimations for the Schwinger functions of relativistic quantum field theories

International Nuclear Information System (INIS)

Mayer, C.D.

1981-01-01

Schwinger functions of a relativistic neutral scalar field the basing test function space of which is S or D are estimated by methods of the analytic continuation. Concerning the behaviour in coincident points it is shown: The two-point singularity of the n-point Schwinger function of a field theory is dominated by an inverse power of the distance of both points modulo a multiplicative constant, if the other n-2 points a sufficiently distant and remain fixed. The power thereby, depends only on n. Using additional conditions on the field the independence of the power on n may be proved. Concerning the behaviour at infinite it is shown: The n-point Schwinger functions of a field theory are globally bounded, if the minimal distance of the arguments is positive. The bound depends only on n and the minimal distance of the arguments. (orig.) [de

Relativistic quantum chaos-An emergent interdisciplinary field.

Science.gov (United States)

Lai, Ying-Cheng; Xu, Hong-Ya; Huang, Liang; Grebogi, Celso

2018-05-01

Quantum chaos is referred to as the study of quantum manifestations or fingerprints of classical chaos. A vast majority of the studies were for nonrelativistic quantum systems described by the Schrödinger equation. Recent years have witnessed a rapid development of Dirac materials such as graphene and topological insulators, which are described by the Dirac equation in relativistic quantum mechanics. A new field has thus emerged: relativistic quantum chaos. This Tutorial aims to introduce this field to the scientific community. Topics covered include scarring, chaotic scattering and transport, chaos regularized resonant tunneling, superpersistent currents, and energy level statistics-all in the relativistic quantum regime. As Dirac materials have the potential to revolutionize solid-state electronic and spintronic devices, a good understanding of the interplay between chaos and relativistic quantum mechanics may lead to novel design principles and methodologies to enhance device performance.

Relativistic quantum chaos—An emergent interdisciplinary field

Science.gov (United States)

Lai, Ying-Cheng; Xu, Hong-Ya; Huang, Liang; Grebogi, Celso

2018-05-01

Quantum chaos is referred to as the study of quantum manifestations or fingerprints of classical chaos. A vast majority of the studies were for nonrelativistic quantum systems described by the Schrödinger equation. Recent years have witnessed a rapid development of Dirac materials such as graphene and topological insulators, which are described by the Dirac equation in relativistic quantum mechanics. A new field has thus emerged: relativistic quantum chaos. This Tutorial aims to introduce this field to the scientific community. Topics covered include scarring, chaotic scattering and transport, chaos regularized resonant tunneling, superpersistent currents, and energy level statistics—all in the relativistic quantum regime. As Dirac materials have the potential to revolutionize solid-state electronic and spintronic devices, a good understanding of the interplay between chaos and relativistic quantum mechanics may lead to novel design principles and methodologies to enhance device performance.

Relativistic Spacecraft Propelled by Directed Energy

Science.gov (United States)

Kulkarni, Neeraj; Lubin, Philip; Zhang, Qicheng

2018-04-01

Achieving relativistic flight to enable extrasolar exploration is one of the dreams of humanity and the long-term goal of our NASA Starlight program. We derive a relativistic solution for the motion of a spacecraft propelled by radiation pressure from a directed energy (DE) system. Depending on the system parameters, low-mass spacecraft can achieve relativistic speeds, thus enabling interstellar exploration. The diffraction of the DE system plays an important role and limits the maximum speed of the spacecraft. We consider “photon recycling” as a possible method to achieving higher speeds. We also discuss recent claims that our previous work on this topic is incorrect and show that these claims arise from an improper treatment of causality.

Spinning relativistic particles in external fields

International Nuclear Information System (INIS)

Pomeranskii, Andrei A; Sen'kov, Roman A; Khriplovich, Iosif B

2000-01-01

The motion of spinning relativistic particles in external electromagnetic and gravitational fields is considered. The self-consistent equations of motion are built with the noncovariant description of spin and with the usual, 'naive' definition of the coordinate of a relativistic particle. A simple derivation of the gravitational interaction of first order in spin is presented for a relativistic particle. The approach developed allows one to consider effects of higher order in spin. Concrete calculations are performed for the second order. The gravimagnetic moment is discussed, a special spin effect in general relativity. We also consider the contributions of the spin interactions of first and second order to the gravitational radiation of compact binary stars. (from the current literature)

New derivation of relativistic dissipative fluid dynamics

International Nuclear Information System (INIS)

Jaiswal, Amaresh; Bhalerao, Rajeev S.; Pal, Subrata

2012-01-01

Relativistic dissipative hydrodynamics has been quite successful in explaining the spectra and azimuthal anisotropy of particles produced in heavy-ion collisions at the RHIC and recently at the LHC. The first-order dissipative fluid dynamics or the relativistic Navier-Stokes (NS) theory involves parabolic differential equations and suffers from a causality and instability. The second-order or Israel-Stewart (IS) theory with its hyperbolic equations restores causality but may not guarantee stability. The correct formulation of relativistic viscous fluid dynamics is far from settled and is under intense investigation

Relativistic current sheets in electron-positron plasmas

International Nuclear Information System (INIS)

Zenitani, S.

2008-01-01

The current sheet structure with magnetic field reversal is one of the fundamental structure in space and astrophysical plasmas. It draws recent attention in high-energy astrophysical settings, where relativistic electron-positron plasmas are considered. In this talk we will review the recent progress of the physical processes in the relativistic current sheet. The kinetic stability of a single current sheet, the nonlinear behavior of these instabilities, and recent challenges on the multi current sheet systems are introduced. We will also introduce some problems of magnetic reconnection in these relativistic environments. (author)

Local density approximations for relativistic exchange energies

International Nuclear Information System (INIS)

MacDonald, A.H.

1986-01-01

The use of local density approximations to approximate exchange interactions in relativistic electron systems is reviewed. Particular attention is paid to the physical content of these exchange energies by discussing results for the uniform relativistic electron gas from a new point of view. Work on applying these local density approximations in atoms and solids is reviewed and it is concluded that good accuracy is usually possible provided self-interaction corrections are applied. The local density approximations necessary for spin-polarized relativistic systems are discussed and some new results are presented

Relativistic astrophysics

CERN Document Server

Price, R H

1993-01-01

Work reported in the workshop on relativistic astrophysics spanned a wide varicy of topics. Two specific areas seemed of particular interest. Much attention was focussed on gravitational wave sources, especially on the waveforms they produce, and progress was reported in theoretical and observational aspects of accretion disks.

Einstein Never Approved of Relativistic Mass

Science.gov (United States)

Hecht, Eugene

2009-01-01

During much of the 20th century it was widely believed that one of the significant insights of special relativity was "relativistic mass." Today there are two schools on that issue: the traditional view that embraces speed-dependent "relativistic mass," and the more modern position that rejects it, maintaining that there is only one mass and it's…

Lectures on relativistic quantum mechanics and path integration

International Nuclear Information System (INIS)

Gunn, J.M.F.

1989-02-01

The question posed is why bother with relativistic quantum mechanics? Three reasons are given: First that there are many experimental phenomena which cannot be explained in non-relativistic terms. Secondly it would be unsatisfactory if relativity and quantum mechanics could not be united. Thirdly, there are theoretical reasons why new effects can be expected at relativistic velocities. The objectives of the course are to set up relativistic analogues of the Schroedinger equation and to understand their consequences. In doing so there are some questions which are raised and discussed such as can a first order equation be used to describe spin 0 particles and a second order equation be used to describe spin 1/ 2 (author)

Relativistic and Non-Relativistic Electronic Molecular-Structure Calculations for Dimers of 4p-, 5p-, and 6p-Block Elements

NARCIS (Netherlands)

Hoefener, S.; Ahlrichs, R.; Knecht, S.; Visscher, L.

2012-01-01

We report results of non-relativistic and two-component relativistic single-reference coupled-cluster with single and double and perturbative triple excitations [CCSD(T)] treatments for the 4p-block dimers Ga

Symmetric low-voltage powering system for relativistic electronic devices

International Nuclear Information System (INIS)

Agafonov, A.V.; Lebedev, A.N.; Krastelev, E.G.

2005-01-01

A special driver for double-sided powering of relativistic magnetrons and several methods of localized electron flow forming in the interaction region of relativistic magnetrons are proposed and discussed. Two experimental installations are presented and discussed. One of them is designed for laboratory research and demonstration experiments at a rather low voltage. The other one is a prototype of a full-scale installation for an experimental research at relativistic levels of voltages on the microwave generation in the new integrated system consisting of a relativistic magnetron and symmetrical induction driver

Lagrangian formulation of a consistent relativistic guiding center theory

International Nuclear Information System (INIS)

Wimmel, H.K.

1983-02-01

A new relativistic guiding center mechanics is presented that conserves energy (in time-independent fields) and satisfies a Liouville's theorem. The theory reduces to Littlejohn's theory in the non-relativistic limit and agrees to leading orders in epsilon identical rsub(g)/L with the relativistic theory by Morozov and Solov'ev (which generally lacks a Liouville's theorem). The new theory is developed from an appropriate Lagrangian and is supplemented by a collisionless relativistic kinetic equation for the guiding centers. Moment equations for guiding center density and energy density are also derived. (orig.)

Relativistic gravitational instabilities

International Nuclear Information System (INIS)

Schutz, B.F.

1987-01-01

The purpose of these lectures is to review and explain what is known about the stability of relativistic stars and black holes, with particular emphases on two instabilities which are due entirely to relativistic effects. The first of these is the post-Newtonian pulsational instability discovered independently by Chandrasekhar (1964) and Fowler (1964). This effectively ruled out the then-popular supermassive star model for quasars, and it sets a limit to the central density of white dwarfs. The second instability was also discovered by Chandrasekhar (1970): the gravitational wave induced instability. This sets an upper bound on the rotation rate of neutron stars, which is near that of the millisecond pulsar PSR 1937+214, and which is beginning to constrain the equation of state of neutron matter. 111 references, 5 figures

The projective geometry of the spacetime yielded by relativistic positioning systems and relativistic location systems

OpenAIRE

Rubin , Jacques ,

2014-01-01

Version de travail de thèse d'habilitation à diriger des recherches; Preprint; Current positioning systems are not primary, relativistic systems. Nevertheless, genuine, relativistic and primary positioning systems have been proposed recently by Bahder, Coll et al. and Rovelli to remedy such prior defects. These new designs all have in common an equivariant conformal geometry featuring, as the most basic ingredient, the spacetime geometry. We show how this conformal aspect can be the four-dime...

Relativistic transport theory for cosmic-rays

International Nuclear Information System (INIS)

Webb, G.M.

1985-01-01

Various aspects of the transport of cosmic-rays in a relativistically moving magnetized plasma supporting a spectrum of hydromagnetic waves that scatter the cosmic-rays are presented. A local Lorentz frame moving with the waves or turbulence scattering the cosmic-rays is used to specify the individual particle momentum. The comoving frame is in general a noninertial frame in which the observer's volume element is expanding and shearing, geometric energy change terms appear in the cosmic-ray transport equation which consist of the relativistic generalization of the adiabatic deceleration term and a further term involving the acceleration vector of the scatterers. A relativistic version of the pitch angle evolution equation, including the effects of adiabatic focussing, pitch angle scattering, and energy changes is presented

Gravitationally confined relativistic neutrinos

Science.gov (United States)

Vayenas, C. G.; Fokas, A. S.; Grigoriou, D.

2017-09-01

Combining special relativity, the equivalence principle, and Newton’s universal gravitational law with gravitational rather than rest masses, one finds that gravitational interactions between relativistic neutrinos with kinetic energies above 50 MeV are very strong and can lead to the formation of gravitationally confined composite structures with the mass and other properties of hadrons. One may model such structures by considering three neutrinos moving symmetrically on a circular orbit under the influence of their gravitational attraction, and by assuming quantization of their angular momentum, as in the Bohr model of the H atom. The model contains no adjustable parameters and its solution, using a neutrino rest mass of 0.05 eV/c2, leads to composite state radii close to 1 fm and composite state masses close to 1 GeV/c2. Similar models of relativistic rotating electron - neutrino pairs give a mass of 81 GeV/c2, close to that of W bosons. This novel mechanism of generating mass suggests that the Higgs mass generation mechanism can be modeled as a latent gravitational field which gets activated by relativistic neutrinos.

Relativistic corrections to molecular dynamic dipole polarizabilities

DEFF Research Database (Denmark)

Kirpekar, Sheela; Oddershede, Jens; Jensen, Hans Jørgen Aagaard

1995-01-01

obtained from the use of the Darwin and mass-velocity operators to first order are included at both levels of approximation. We find that correlation and relativistic contributions are not even approximately additive for the two molecules. The importance of the relativistic corrections is smallest...

From Lattice Boltzmann to hydrodynamics in dissipative relativistic fluids

Science.gov (United States)

Gabbana, Alessandro; Mendoza, Miller; Succi, Sauro; Tripiccione, Raffaele

2017-11-01

Relativistic fluid dynamics is currently applied to several fields of modern physics, covering many physical scales, from astrophysics, to atomic scales (e.g. in the study of effective 2D systems such as graphene) and further down to subnuclear scales (e.g. quark-gluon plasmas). This talk focuses on recent progress in the largely debated connection between kinetic transport coefficients and macroscopic hydrodynamic parameters in dissipative relativistic fluid dynamics. We use a new relativistic Lattice Boltzmann method (RLBM), able to handle from ultra-relativistic to almost non-relativistic flows, and obtain strong evidence that the Chapman-Enskog expansion provides the correct pathway from kinetic theory to hydrodynamics. This analysis confirms recently obtained theoretical results, which can be used to obtain accurate calibrations for RLBM methods applied to realistic physics systems in the relativistic regime. Using this calibration methodology, RLBM methods are able to deliver improved physical accuracy in the simulation of the physical systems described above. European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 642069.

Scalar Relativistic Study of the Structure of Rhodium Acetate

Directory of Open Access Journals (Sweden)

Emily E. Edwards

2004-01-01

Full Text Available Abstract: Rhodium acetate, related rhodium carboxylates, and rhodium amide complexes are powerful catalysts for carbene chemistry. They readily promote the decomposition of diazo compounds and transfer the resulting carbene to a variety of substrates. There have been several quantum chemistry studies of these compounds, particularly of the acetate. These have all used non-relativistic methods, and all have shown optimized Rh-Rh bond lengths significantly longer than the experimental value. In this study we have surveyed several scalar relativistic DFT methods using Gaussian, Slater, and numerical basis functions (in DGAUSS, ADF, and DMOL3. Several combinations of exchange-correlation functionals with relativistic and non-relativistic effective core potentials (ECP were investigated, as were non-relativistic and all electron scalar relativistic methods. The combination of the PW91 exchange and PW91 correlation functional with the Christiansen-Ermler ECP gave the best results: 2.3918 Å compared to the experimental value of 2.3855±0.0005 Å.

Holographic Aspects of a Relativistic Nonconformal Theory

Directory of Open Access Journals (Sweden)

Chanyong Park

2013-01-01

Full Text Available We study a general D-dimensional Schwarzschild-type black brane solution of the Einstein-dilaton theory and derive, by using the holographic renormalization, its thermodynamics consistent with the geometric results. Using the membrane paradigm, we calculate the several hydrodynamic transport coefficients and compare them with the results obtained by the Kubo formula, which shows the self-consistency of the gauge/gravity duality in the relativistic nonconformal theory. In order to understand more about the relativistic non-conformal theory, we further investigate the binding energy, drag force, and holographic entanglement entropy of the relativistic non-conformal theory.

On the physics of relativistic double layers

International Nuclear Information System (INIS)

Carlqvist, P.

1982-06-01

A model of a strong, time-independent, and relativistic double layer is studied. Besides double layers having the electric field parallel to the current the model also describes a certain type of oblique double layers. The 'Langmuir condition' (ratio of ion current density to electron current density) as well as an expression for the potential drop of the double layer are derived. Furthermore, the distribution of charged particles, electric field, and potential within the double layer are clarified and discussed. It is found that the properties of relativistic double layers differ substantially from the properties of corresponding non-relativistic double layers. (Author)

Two-dimensional approach to relativistic positioning systems

International Nuclear Information System (INIS)

Coll, Bartolome; Ferrando, Joan Josep; Morales, Juan Antonio

2006-01-01

A relativistic positioning system is a physical realization of a coordinate system consisting in four clocks in arbitrary motion broadcasting their proper times. The basic elements of the relativistic positioning systems are presented in the two-dimensional case. This simplified approach allows to explain and to analyze the properties and interest of these new systems. The positioning system defined by geodesic emitters in flat metric is developed in detail. The information that the data generated by a relativistic positioning system give on the space-time metric interval is analyzed, and the interest of these results in gravimetry is pointed out

Methyl cation affinities of neutral and anionic maingroup-element hydrides: trends across the periodic table and correlation with proton affinities.

Science.gov (United States)

Mulder, R Joshua; Guerra, Célia Fonseca; Bickelhaupt, F Matthias

2010-07-22

We have computed the methyl cation affinities in the gas phase of archetypal anionic and neutral bases across the periodic table using ZORA-relativistic density functional theory (DFT) at BP86/QZ4P//BP86/TZ2P. The main purpose of this work is to provide the methyl cation affinities (and corresponding entropies) at 298 K of all anionic (XH(n-1)(-)) and neutral bases (XH(n)) constituted by maingroup-element hydrides of groups 14-17 and the noble gases (i.e., group 18) along the periods 2-6. The cation affinity of the bases decreases from H(+) to CH(3)(+). To understand this trend, we have carried out quantitative bond energy decomposition analyses (EDA). Quantitative correlations are established between the MCA and PA values.

The Concept of Neutrality with Regard to Gender and Religion: A Critique Exemplified by the Approach of Martha Nussbaum

Directory of Open Access Journals (Sweden)

Cornelia Mügge

2015-12-01

Full Text Available This article is about the meaning and the plausibility of the concept of neutrality with regard to debates on gender and religion in political philosophy. As an example, it takes the Capabilities Approach of Martha Nussbaum, which is particularly instructive as she advocates neutrality between comprehensive doctrines and, at the same time, attends to the challenges posed by gender and religion. Starting from an explanation of the meaning of the concept of neutrality in Nussbaum’s approach, the article focuses on objections against neutrality raised by feminist approaches. It discusses Nussbaum’s defence of neutrality and asks whether it is convincing or not, and to what extent. The article suggests a differentiation between neutrality as an ideal and the attribution of neutrality to actual political norms. It further argues that, whereas Nussbaum’s approach implies the latter conception, the former better corresponds to the basic norm of equal respect.

Phase Transition Behavior in a Neutral Evolution Model

Science.gov (United States)

King, Dawn; Scott, Adam; Maric, Nevena; Bahar, Sonya

2014-03-01

The complexity of interactions among individuals and between individuals and the environment make agent based modeling ideal for studying emergent speciation. This is a dynamically complex problem that can be characterized via the critical behavior of a continuous phase transition. Concomitant with the main tenets of natural selection, we allow organisms to reproduce, mutate, and die within a neutral phenotype space. Previous work has shown phase transition behavior in an assortative mating model with variable fitness landscapes as the maximum mutation size (μ) was varied (Dees and Bahar, 2010). Similarly, this behavior was recently presented in the work of Scott et al. (2013), even on a completely neutral landscape, for bacterial-like fission as well as for assortative mating. Here we present another neutral model to investigate the `critical' phase transition behavior of three mating types - assortative, bacterial, and random - in a phenotype space as a function of the percentage of random death. Results show two types of phase transitions occurring for the parameters of the population size and the number of clusters (an analogue of species), indicating different evolutionary dynamics for system survival and clustering. This research was supported by funding from: University of Missouri Research Board and James S. McDonnell Foundation.

Analytic neutrality, anonymity, abstinence, and elective self-disclosure.

Science.gov (United States)

Shill, Merton A

2004-01-01

Recent contributions to the psychoanalytic literature propose new ways of understanding analytic neutrality, anonymity, abstinence, and self-disclosure. They advocate elective self-disclosure by the analyst as an antidote to the allegedly game-playing quality of transference and resistance analysis. The analytic relationship, they assert, becomes unreal when attempts are made to observe the principles of neutrality and abstinence. Both are seen as ill-conceived because of the irreducible subjectivity and unwarranted authority of the analyst. These relational and interactional views are criticized because (1) they ignore the fact that transference and resistance analysis have from Freud onward been accepted as minimal criteria qualifying a clinical process as psychoanalytic; (2) elective self-disclosure carries metapsychological implications dismissing not only Freud's theory of motivation but motivation as a basic feature of human personality; (3) they do not recognize interpersonal relations as mental events and so do not consider the ego's ability to create intrapsychic representations of object relations; (4) elective self-disclosures within the empathic parameters of the analytic situation are themselves unreal compared to the reality of the patient's experience with other objects. Abstinence and neutrality as ideals facilitate maintenance of an internal holding environment or container for the analyst's countertransference.

Relativistic calculations of coalescing binary neutron stars

Indian Academy of Sciences (India)

We have designed and tested a new relativistic Lagrangian hydrodynamics code, which treats gravity in the conformally flat approximation to general relativity. We have tested the resulting code extensively, finding that it performs well for calculations of equilibrium single-star models, collapsing relativistic dust clouds, and ...

Deep processes in non-relativistic confining potentials

International Nuclear Information System (INIS)

Fishbane, P.M.; Grisaru, M.T.

1978-01-01

The authors study deep inelastic and hard scattering processes for non-relativistic particles confined in deep potentials. The mechanisms by which the effects of confinement disappear and the particles scatter as if free are useful in understanding the analogous results for a relativistic field theory. (Auth.)

The effects of "thin ideal" media on women's body image concerns and eating-related intentions: the beneficial role of an autonomous regulation of eating behaviors.

Science.gov (United States)

Mask, Lisa; Blanchard, Céline M

2011-09-01

The present study examines the protective role of an autonomous regulation of eating behaviors (AREB) on the relationship between trait body dissatisfaction and women's body image concerns and eating-related intentions in response to "thin ideal" media. Undergraduate women (n=138) were randomly assigned to view a "thin ideal" video or a neutral video. As hypothesized, trait body dissatisfaction predicted more negative affect and size dissatisfaction following exposure to the "thin ideal" video among women who displayed less AREB. Conversely, trait body dissatisfaction predicted greater intentions to monitor food intake and limit unhealthy foods following exposure to the "thin ideal" video among women who displayed more AREB. Copyright © 2011 Elsevier Ltd. All rights reserved.

Isolating relativistic effects in large-scale structure

Science.gov (United States)

Bonvin, Camille

2014-12-01

We present a fully relativistic calculation of the observed galaxy number counts in the linear regime. We show that besides the density fluctuations and redshift-space distortions, various relativistic effects contribute to observations at large scales. These effects all have the same physical origin: they result from the fact that our coordinate system, namely the galaxy redshift and the incoming photons’ direction, is distorted by inhomogeneities in our Universe. We then discuss the impact of the relativistic effects on the angular power spectrum and on the two-point correlation function in configuration space. We show that the latter is very well adapted to isolate the relativistic effects since it naturally makes use of the symmetries of the different contributions. In particular, we discuss how the Doppler effect and the gravitational redshift distortions can be isolated by looking for a dipole in the cross-correlation function between a bright and a faint population of galaxies.

Report of seminar on relativistic approach to nuclear reaction and nuclear structure

International Nuclear Information System (INIS)

1986-05-01

A seminar on 'Relativistic Approach to Nuclear Reaction and Nuclear Structure' was held in 1985 at Osaka University. This booklet includes twenty-four reports given at the seminar, which deal with: Conventional Nonrelativistic Description of Nuclear Matter and Nuclear Spin-Orbit Interactions; Relativistic Approach to Nuclear Structure; Atomic and Molecular Structure Calculations; Electromagnetic Interaction in Nucleus and Relativistic Effect; Nuclear Magnetic Moment in the Relativistic Mean Field Theory, Effective Mass and Particle-Vibration Coupling in the Relativistic σ-ω Model; Gauge Invariance in Relativistic Many-Body Theory; Relativistic Description of Nucleon-Nucleon Interaction in Review; σ-Particle in NN Interaction; Nuclear Optical Potentials Based on the Brueckner-Hartree-Fock Approach; Elastic Backscattering and Optical Potential; Description of Intermediate-Energy Nuclear Reactions; Dirac Phenomenology at E(p) = 65 MeV; Relativistic Impulse Approximation; Reaction Studies with Intermediate Energy Deuterons at SATURNE; Folding Model for Intermediate-Energy Deutron Scattering; Folding Model for Polarized Deutron Scattering at 700 MeV; Dirac Approach Problems and a Different Viewpoint; Relativistic Approach and EMC Effect; Quasielastic Electron Scattering; Response Function of Quasielastic Electron Scattering; Relativistic Hartree Response Function for Quasielastic Electron Scattering on 12 C and 40 Ca; Backflow-, Retardation- and Relativistic Effects on the Longitudinal Response Function of Nuclear Matter; Pion-Photoproduction in the σ-ω Model. (Nogami, K.)

Electromagnetic interactions in relativistic infinite component wave equations

International Nuclear Information System (INIS)

Gerry, C.C.

1979-01-01

The electromagnetic interactions of a composite system described by relativistic infinite-component wave equations are considered. The noncompact group SO(4,2) is taken as the dynamical group of the systems, and its unitary irreducible representations, which are infinite dimensional, are used to find the energy spectra and to specify the states of the systems. First the interaction mechanism is examined in the nonrelativistic SO(4,2) formulation of the hydrogen atom as a heuristic guide. A way of making a minimal relativistic generalization of the minimal ineractions in the nonrelativistic equation for the hydrogen atom is proposed. In order to calculate the effects of the relativistic minimal interactions, a covariant perturbation theory suitable for infinite-component wave equations, which is an algebraic and relativistic version of the Rayleigh-Schroedinger perturbation theory, is developed. The electric and magnetic polarizabilities for the ground state of the hydrogen atom are calculated. The results have the correct nonrelativistic limits. Next, the relativistic cross section of photon absorption by the atom is evaluated. A relativistic expression for the cross section of light scattering corresponding to the seagull diagram is derived. The Born amplitude is combusted and the role of spacelike solutions is discussed. Finally, internal electromagnetic interactions that give rise to the fine structure splittings, the Lamb shifts and the hyperfine splittings are considered. The spin effects are introduced by extending the dynamical group

Are "Market Neutral" Hedge Funds Really Market Neutral?

OpenAIRE

Andrew J. Patton

2009-01-01

Using a variety of different definitions of "neutrality," this study presents significant evidence against the neutrality to market risk of hedge funds in a range of style categories. I generalize standard definitions of "market neutrality," and propose five different neutrality concepts. I suggest statistical tests for each neutrality concept, and apply these tests to a database of monthly returns on 1423 hedge funds from five style categories. For the "market neutral" style, approximately o...

Is a Relativistic Thermodynamics possible?; Es posible una Termodinamica Relativista?

Energy Technology Data Exchange (ETDEWEB)

Guemez, J.

2010-07-01

A brief historical review the literature on developing the concept of Thermodynamics Relativistic. We analyze two examples of application of the Galilean and Relativistic Thermodynamics discussed under what circumstances could build a relativistic Thermodynamics Lorentz covariant with physical sense. (Author) 19 refs.

Study of the O-mode in a relativistic degenerate electron plasma

Science.gov (United States)

Azra, Kalsoom; Ali, Muddasir; Hussain, Azhar

2017-03-01

Using the linearized relativistic Vlasov-Maxwell equations, a generalized expression for the plasma conductivity tensor is derived. The dispersion relation for the O-mode in a relativistic degenerate electron plasma is investigated by employing the Fermi-Dirac distribution function. The propagation characteristics of the O-mode (cut offs, resonances, propagation regimes, harmonic structure) are examined by using specific values of the density and the magnetic field that correspond to different relativistic dense environments. Further, it is observed that due to the relativistic effects the cut off and the resonance points are shifted to low frequency values, as a result the propagation regime is reduced. The dispersion relations for the non-relativistic and the ultra-relativistic limits are also presented.

Relativistic Calculations for Be-like Iron

International Nuclear Information System (INIS)

Yang Jianhui; Zhang Jianping; Li Ping; Li Huili

2008-01-01

Relativistic configuration interaction calculations for the states of 1s 2 2s 2 , 1s 2 2s3l (l = s,p,d) and 1s 2 2p3l (l = s,p,d) configurations of iron are carried out using relativistic configuration interaction (RCI) and multi-configuration Dirac-Fock (MCDF) method in the active interaction approach. In the present calculation, a large-scale configuration expansion was used in describing the target states. These results are extensively compared with other available calculative and experimental and observed values, the corresponding present results are in good agreement with experimental and observed values, and some differences are found with other available calculative values. Because more relativistic effects are considered than before, the present results should be more accurate and reliable

Relativistic dynamical reduction models and nonlocality

International Nuclear Information System (INIS)

Ghirardi, G.C.; Grassi, R.

1990-09-01

We discuss some features of continuous dynamical models yielding state vector reduction and we briefly sketch some recent attempts to get a relativistic generalization of them. Within the relativistic context we analyze in detail the local an nonlocal features of the reduction mechanism and we investigate critically the possibility of attributing objective properties to individual systems in the micro and macroscopic cases. At the nonrelativistic level, two physically equivalent versions of continuous reduction mechanisms have been presented. However, only one of them can be taken as a starting point for the above considered relativistic generalization. By resorting to counterfactual arguments we show that the reason for this lies in the fact that the stochasticity involved in the two approaches has different conceptual implications. (author). 7 refs, 4 figs

Weinhold'length in an isentropic Ideal and quasi-Ideal Gas

OpenAIRE

Santoro, Manuel

2004-01-01

In this paper we study thermodynamic length of an isentropic Ideal and quasi-Ideal Gas using Weinhold metric in a two-dimensional state space. We give explicit relation between length at constant entropy and work.

Weinhold length in an isentropic ideal and quasi-ideal gas

International Nuclear Information System (INIS)

Santoro, Manuel

2005-01-01

In this paper, we study thermodynamic length of an isentropic ideal and quasi-ideal gas using Weinhold metric in a two-dimensional state space. We give explicit relation between length at constant entropy and work

LSP Simulations of the Neutralized Drift Compression Experiment

CERN Document Server

Thoma, Carsten H; Gilson, Erik P; Henestroza, Enrique; Roy, Prabir K; Welch, Dale; Yu, Simon

2005-01-01

The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory involves the longitudinal compression of a singly-stripped K ion beam with a mean energy of 250 keV in a meter long plasma. We present simulation results of compression of the NDCX beam using the PIC code LSP. The NDCX beam encounters an acceleration gap with a time-dependent voltage that decelerates the front and accelerates the tail of a 500 ns pulse which is to be compressed 110 cm downstream. The simulations model both ideal and experimental voltage waveforms. Results show good longitudinal compression without significant emittance growth.

Recent progresses in relativistic beam-plasma instability theory

Directory of Open Access Journals (Sweden)

A. Bret

2010-11-01

Full Text Available Beam-plasma instabilities are a key physical process in many astrophysical phenomena. Within the fireball model of Gamma ray bursts, they first mediate a relativistic collisionless shock before they produce upstream the turbulence needed for the Fermi acceleration process. While non-relativistic systems are usually governed by flow-aligned unstable modes, relativistic ones are likely to be dominated by normally or even obliquely propagating waves. After reviewing the basis of the theory, results related to the relativistic kinetic regime of the poorly-known oblique unstable modes will be presented. Relevant systems besides the well-known electron beam-plasma interaction are presented, and it is shown how the concept of modes hierarchy yields a criterion to assess the proton to electron mass ratio in Particle in cell simulations.

Rayleigh-Brillouin spectrum in special relativistic hydrodynamics

International Nuclear Information System (INIS)

Garcia-Perciante, A. L.; Garcia-Colin, L. S.; Sandoval-Villalbazo, A.

2009-01-01

In this paper we calculate the Rayleigh-Brillouin spectrum for a relativistic simple fluid according to three different versions available for a relativistic approach to nonequilibrium thermodynamics. An outcome of these calculations is that Eckart's version predicts that such spectrum does not exist. This provides an argument to question its validity. The remaining two results, which differ one from another, do provide a finite form for such spectrum. This raises the rather intriguing question as to which of the two theories is a better candidate to be taken as a possible version of relativistic nonequilibrium thermodynamics. The answer will clearly require deeper examination of this problem.

(Fuzzy) Ideals of BN-Algebras

Science.gov (United States)

Walendziak, Andrzej

2015-01-01

The notions of an ideal and a fuzzy ideal in BN-algebras are introduced. The properties and characterizations of them are investigated. The concepts of normal ideals and normal congruences of a BN-algebra are also studied, the properties of them are displayed, and a one-to-one correspondence between them is presented. Conditions for a fuzzy set to be a fuzzy ideal are given. The relationships between ideals and fuzzy ideals of a BN-algebra are established. The homomorphic properties of fuzzy ideals of a BN-algebra are provided. Finally, characterizations of Noetherian BN-algebras and Artinian BN-algebras via fuzzy ideals are obtained. PMID:26125050

A neural network model of the relativistic electron flux at geosynchronous orbit

International Nuclear Information System (INIS)

Koons, H.C.; Gorney, D.J.

1991-01-01

A neural network has been developed to model the temporal variations of relativistic (>3 MeV) electrons at geosynchronous orbit based on model inputs consisting of 10 consecutive days of the daily sum of the planetary magnetic index ΣKp. The neural network consists of three layers of neurons, containing 10 neurons in the input layer, 6 neurons in a hidden layer, and 1 output neuron. The output is a prediction of the daily-averaged electron flux for the tenth day. The neural network was trained using 62 days of data from July 1, 1984, through August 31, 1984, from the SEE spectrometer on the geosynchronous spacecraft 1982-019. The performance of the model was measured by comparing model outputs with measured fluxes over a 6-year period from April 19, 1982, to June 4, 1988. For the entire data set the rms logarithmic error of the neural network is 0.76, and the average logarithmic error is 0.58. The neural network is essentially zero biased, and for accumulation intervals of 3 days or longer the average logarithmic error is less than 0.1. The neural network provides results that are significantly more accurate than those from linear prediction filters. The model has been used to simulate conditions which are rarely observed in nature, such as long periods of quiet (ΣKp = 0) and ideal impulses. It has also been used to make reasonably accurate day-ahead forecasts of the relativistic electron flux at geosynchronous orbit

Frontiers in relativistic celestial mechanics

CERN Document Server

2014-01-01

Relativistic celestial mechanics – investigating the motion celestial bodies under the influence of general relativity – is a major tool of modern experimental gravitational physics. With a wide range of prominent authors from the field, this two-volume series consists of reviews on a multitude of advanced topics in the area of relativistic celestial mechanics – starting from more classical topics such as the regime of asymptotically-flat spacetime, light propagation and celestial ephemerides, but also including its role in cosmology and alternative theories of gravity as well as modern experiments in this area.

Chiral quark model with relativistic kinematics

International Nuclear Information System (INIS)

Garcilazo, H.; Valcarce, A.

2003-01-01

The nonstrange baryon spectrum is studied within a three-body model that incorporates relativistic kinematics. We found that the combined effect of relativistic kinematics together with the pion exchange between quarks is able to reverse the order of the first positive- and negative-parity nucleon excited states as observed experimentally. Including the chiral partner of the pion (the σ meson) leads to an overall good description of the spectrum

Chiral quark model with relativistic kinematics

OpenAIRE

Garcilazo, H.; Valcarce, A.

2003-01-01

The non-strange baryon spectrum is studied within a three-body model that incorporates relativistic kinematics. We found that the combined effect of relativistic kinematics together with the pion exchange between quarks is able to reverse the order of the first positive- and negative-parity nucleon excited states as observed experimentally. Including the chiral partner of the pion (the $\\sigma$ meson) leads to an overall good description of the spectrum.

PHYSICAL-CONSTRAINT-PRESERVING CENTRAL DISCONTINUOUS GALERKIN METHODS FOR SPECIAL RELATIVISTIC HYDRODYNAMICS WITH A GENERAL EQUATION OF STATE

Energy Technology Data Exchange (ETDEWEB)

Wu, Kailiang [School of Mathematical Sciences, Peking University, Beijing 100871 (China); Tang, Huazhong, E-mail: wukl@pku.edu.cn, E-mail: hztang@math.pku.edu.cn [HEDPS, CAPT and LMAM, School of Mathematical Sciences, Peking University, Beijing 100871 (China)

2017-01-01

The ideal gas equation of state (EOS) with a constant adiabatic index is a poor approximation for most relativistic astrophysical flows, although it is commonly used in relativistic hydrodynamics (RHD). This paper develops high-order accurate, physical-constraints-preserving (PCP), central, discontinuous Galerkin (DG) methods for the one- and two-dimensional special RHD equations with a general EOS. It is built on our theoretical analysis of the admissible states for RHD and the PCP limiting procedure that enforce the admissibility of central DG solutions. The convexity, scaling invariance, orthogonal invariance, and Lax–Friedrichs splitting property of the admissible state set are first proved with the aid of its equivalent form. Then, the high-order central DG methods with the PCP limiting procedure and strong stability-preserving time discretization are proved, to preserve the positivity of the density, pressure, specific internal energy, and the bound of the fluid velocity, maintain high-order accuracy, and be L {sup 1}-stable. The accuracy, robustness, and effectiveness of the proposed methods are demonstrated by several 1D and 2D numerical examples involving large Lorentz factor, strong discontinuities, or low density/pressure, etc.

Acoustic geometry for general relativistic barotropic irrotational fluid flow

International Nuclear Information System (INIS)

Visser, Matt; Molina-ParIs, Carmen

2010-01-01

'Acoustic spacetimes', in which techniques of differential geometry are used to investigate sound propagation in moving fluids, have attracted considerable attention over the last few decades. Most of the models currently considered in the literature are based on non-relativistic barotropic irrotational fluids, defined in a flat Newtonian background. The extension, first to special relativistic barotropic fluid flow and then to general relativistic barotropic fluid flow in an arbitrary background, is less straightforward than it might at first appear. In this paper, we provide a pedagogical and simple derivation of the general relativistic 'acoustic spacetime' in an arbitrary (d+1)-dimensional curved-space background.

Non-relativistic spinning particle in a Newton-Cartan background

Science.gov (United States)

Barducci, Andrea; Casalbuoni, Roberto; Gomis, Joaquim

2018-01-01

We construct the action of a non-relativistic spinning particle moving in a general torsionless Newton-Cartan background. The particle does not follow the geodesic equations, instead the motion is governed by the non-relativistic analog of Papapetrou equation. The spinning particle is described in terms of Grassmann variables. In the flat case the action is invariant under the non-relativistic analog of space-time vector supersymmetry.

Fully relativistic free-electron laser in a completely filled waveguide

International Nuclear Information System (INIS)

Farokhi, B.; Abdykian, A.

2005-01-01

An analysis of the azimuthally symmetrical, high frequency eigenmodes of a cylindrical metallic waveguide completely filled with a relativistic magnetized plasma is presented. A relativistic nonlinear wave equation is derived in a form which includes the coupling of EH and HE modes due to the finite axial magnetic field. Relativistic equations that permit calculation of the dispersion curves for four families of electromagnetic and electrostatic modes are derived. Numerical analysis is conducted to study the relativistic dispersion curves of various modes as a function of axial magnetic field B 0 . This treatment is shown that the dispersion curves dependent to γ in low frequency which is ignored in previous work. It is found that in drawn figures shown difference between relativistic and non-relativistic cases. The former each figure is treated for two orbit groups. This study is benefiting to facilities the development of devices for generation of high-power electromagnetic radiation, charged particle acceleration, and other applications of plasma waveguide. (author)

Relativistic modeling capabilities in PERSEUS extended MHD simulation code for HED plasmas

Energy Technology Data Exchange (ETDEWEB)

Hamlin, Nathaniel D., E-mail: nh322@cornell.edu [438 Rhodes Hall, Cornell University, Ithaca, NY, 14853 (United States); Seyler, Charles E., E-mail: ces7@cornell.edu [Cornell University, Ithaca, NY, 14853 (United States)

2014-12-15

We discuss the incorporation of relativistic modeling capabilities into the PERSEUS extended MHD simulation code for high-energy-density (HED) plasmas, and present the latest hybrid X-pinch simulation results. The use of fully relativistic equations enables the model to remain self-consistent in simulations of such relativistic phenomena as X-pinches and laser-plasma interactions. By suitable formulation of the relativistic generalized Ohm’s law as an evolution equation, we have reduced the recovery of primitive variables, a major technical challenge in relativistic codes, to a straightforward algebraic computation. Our code recovers expected results in the non-relativistic limit, and reveals new physics in the modeling of electron beam acceleration following an X-pinch. Through the use of a relaxation scheme, relativistic PERSEUS is able to handle nine orders of magnitude in density variation, making it the first fluid code, to our knowledge, that can simulate relativistic HED plasmas.

Properties of nuclear and neutron matter in a relativistic Hartree-Fock theory

International Nuclear Information System (INIS)

Horowitz, C.J.; Serot, B.D.

1983-01-01

Relativistic-Hartree-Fock (HF) equations are derived for an infinite system of mesons and baryons in the framework of a renormalizable relativistic quantum field theory. The derivation is based on a diagrammatic approach and Dyson's equation for the baryon propagator. The result is a set of coupled, nonlinear integral equations for the baryon self-energy with a self-consistency condition on the single-particle spectrum. The HF equations are solved for nuclear and neutron matter in the Walecka model, which contains neutral scalar and vector mesons. After renormalizing model parameters to reproduce nuclear matter saturation properties, HF results at low to moderate densities are similar to those in the mean-field (Hartree) approximation. Self-consistent exchange corrections to the Hartree equation of state become negligible at high densities. Rho- and pi-meson exchanges are incorporated using a renormalizable gauge-theory model. A chiral transformation of the lagrangian is used to replace the pseudoscalar πN coupling with a pseudovector coupling, for which one-pion exchange is a reasonable first approximation. This transformation maintains the model's renormalizability so that corrections may be evaluated. Pion exchange has a small effect on the HF results of the Walecka model and brings HF results in closer in closer agreement with the mean-field theory. The diagrammatic techniques used here retain the mesonic degrees of freedom and are simple enough to be extended to more refined self-consistent approximations. (orig.)

RELATIVISTIC DOPPLER BEAMING AND MISALIGNMENTS IN AGN JETS

International Nuclear Information System (INIS)

Singal, Ashok K.

2016-01-01

Radio maps of active galactic nuclei often show linear features, called jets, on both parsec and kiloparsec scales. These jets supposedly possess relativistic motion and are oriented close to the line of sight of the observer, and accordingly the relativistic Doppler beaming makes them look much brighter than they really are in their respective rest frames. The flux boosting due to the relativistic beaming is a very sensitive function of the jet orientation angle, as seen by the observer. Sometimes, large bends are seen in these jets, with misalignments being 90° or more, which might imply a change in the orientation angle that should cause a large change in the relativistic beaming factor. Hence, if relativistic beaming does play an important role in these jets such large bends should usually show high contrast in the brightness of the jets before and after the bend. It needs to be kept in mind that sometimes a small intrinsic change in the jet angle might appear as a much larger misalignment due to the effects of geometrical projection, especially when seen close to the line of sight. What really matters are the initial and final orientation angles of the jet with respect to the observer’s line of sight. Taking the geometrical projection effects properly into account, we calculate the consequences of the presumed relativistic beaming and demonstrate that there ought to be large brightness ratios in jets before and after the observed misalignments.

Relativistic Doppler Beaming and Misalignments in AGN Jets

Science.gov (United States)

Singal, Ashok K.

2016-08-01

Radio maps of active galactic nuclei often show linear features, called jets, on both parsec and kiloparsec scales. These jets supposedly possess relativistic motion and are oriented close to the line of sight of the observer, and accordingly the relativistic Doppler beaming makes them look much brighter than they really are in their respective rest frames. The flux boosting due to the relativistic beaming is a very sensitive function of the jet orientation angle, as seen by the observer. Sometimes, large bends are seen in these jets, with misalignments being 90° or more, which might imply a change in the orientation angle that should cause a large change in the relativistic beaming factor. Hence, if relativistic beaming does play an important role in these jets such large bends should usually show high contrast in the brightness of the jets before and after the bend. It needs to be kept in mind that sometimes a small intrinsic change in the jet angle might appear as a much larger misalignment due to the effects of geometrical projection, especially when seen close to the line of sight. What really matters are the initial and final orientation angles of the jet with respect to the observer’s line of sight. Taking the geometrical projection effects properly into account, we calculate the consequences of the presumed relativistic beaming and demonstrate that there ought to be large brightness ratios in jets before and after the observed misalignments.

Relativistic Polarizable Embedding

DEFF Research Database (Denmark)

Hedegård, Erik Donovan; Bast, Radovan; Kongsted, Jacob

2017-01-01

Most chemistry, including chemistry where relativistic effects are important, occurs in an environment, and in many cases, this environment has a significant effect on the chemistry. In nonrelativistic quantum chemistry, a lot of progress has been achieved with respect to including environments s...

A new perspective on relativistic transformation for Maxwell's equations of electrodynamics

International Nuclear Information System (INIS)

Huang, Y.-S.

2009-01-01

A new scheme for relativistic transformation of the electromagnetic fields is formulated through relativistic transformation in the wavevector space, instead of the space-time space. Maxwell's equations of electrodynamics are shown to be form-invariant among inertial frames in accordance with this new scheme of relativistic transformation. This new perspective on relativistic transformation not only fulfills the principle of relativity, but is also compatible with quantum theory.

Relativistic laser channeling in plasmas for fast ignition

Science.gov (United States)

Lei, A. L.; Pukhov, A.; Kodama, R.; Yabuuchi, T.; Adumi, K.; Endo, K.; Freeman, R. R.; Habara, H.; Kitagawa, Y.; Kondo, K.; Kumar, G. R.; Matsuoka, T.; Mima, K.; Nagatomo, H.; Norimatsu, T.; Shorokhov, O.; Snavely, R.; Yang, X. Q.; Zheng, J.; Tanaka, K. A.

2007-12-01

We report an experimental observation suggesting plasma channel formation by focusing a relativistic laser pulse into a long-scale-length preformed plasma. The channel direction coincides with the laser axis. Laser light transmittance measurement indicates laser channeling into the high-density plasma with relativistic self-focusing. A three-dimensional particle-in-cell simulation reproduces the plasma channel and reveals that the collimated hot-electron beam is generated along the laser axis in the laser channeling. These findings hold the promising possibility of fast heating a dense fuel plasma with a relativistic laser pulse.

On the convexity of relativistic hydrodynamics

International Nuclear Information System (INIS)

Ibáñez, José M; Martí, José M; Cordero-Carrión, Isabel; Miralles, Juan A

2013-01-01

The relativistic hydrodynamic system of equations for a perfect fluid obeying a causal equation of state is hyperbolic (Anile 1989 Relativistic Fluids and Magneto-Fluids (Cambridge: Cambridge University Press)). In this report, we derive the conditions for this system to be convex in terms of the fundamental derivative of the equation of state (Menikoff and Plohr1989 Rev. Mod. Phys. 61 75). The classical limit is recovered. Communicated by L Rezzolla (note)

Limits and signatures of relativistic spaceflight

Science.gov (United States)

Yurtsever, Ulvi; Wilkinson, Steven

2018-01-01

While special relativity imposes an absolute speed limit at the speed of light, our Universe is not empty Minkowski spacetime. The constituents that fill the interstellar/intergalactic vacuum, including the cosmic microwave background photons, impose a lower speed limit on any object travelling at relativistic velocities. Scattering of cosmic microwave photons from an ultra-relativistic object may create radiation with a characteristic signature allowing the detection of such objects at large distances.

Angular analyses in relativistic quantum mechanics; Analyses angulaires en mecanique quantique relativiste

Energy Technology Data Exchange (ETDEWEB)

Moussa, P [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires

1968-06-01

This work describes the angular analysis of reactions between particles with spin in a fully relativistic fashion. One particle states are introduced, following Wigner's method, as representations of the inhomogeneous Lorentz group. In order to perform the angular analyses, the reduction of the product of two representations of the inhomogeneous Lorentz group is studied. Clebsch-Gordan coefficients are computed for the following couplings: l-s coupling, helicity coupling, multipolar coupling, and symmetric coupling for more than two particles. Massless and massive particles are handled simultaneously. On the way we construct spinorial amplitudes and free fields; we recall how to establish convergence theorems for angular expansions from analyticity hypothesis. Finally we substitute these hypotheses to the idea of 'potential radius', which gives at low energy the usual 'centrifugal barrier' factors. The presence of such factors had never been deduced from hypotheses compatible with relativistic invariance. (author) [French] On decrit un formalisme permettant de tenir compte de l'invariance relativiste, dans l'analyse angulaire des amplitudes de reaction entre particules de spin quelconque. Suivant Wigner, les etats a une particule sont introduits a l'aide des representations du groupe de Lorentz inhomogene. Pour effectuer les analyses angulaires, on etudie la reduction du produit de deux representations du groupe de Lorentz inhomogene. Les coefficients de Clebsch-Gordan correspondants sont calcules dans les couplages suivants: couplage l-s couplage d'helicite, couplage multipolaire, couplage symetrique pour plus de deux particules. Les particules de masse nulle et de masse non nulle sont traitees simultanement. Au passage, on introduit les amplitudes spinorielles et on construit les champs libres, on rappelle comment des hypotheses d'analyticite permettent d'etablir des theoremes de convergence pour les developpements angulaires. Enfin on fournit un substitut a la

Gravitation relativiste

CERN Document Server

Hakim, Rémi

1994-01-01

Il existe à l'heure actuelle un certain nombre de théories relativistes de la gravitation compatibles avec l'expérience et l'observation. Toutefois, la relativité générale d'Einstein fut historiquement la première à fournir des résultats théoriques corrects en accord précis avec les faits.

Relativistic klystron

International Nuclear Information System (INIS)

Marks, R.

1985-09-01

Theoretical analysis is presented of a relativisic klystron; i.e. a high-relativistic bunched electron beam which is sent through a succession of tuned cavities and has its energy replenished by periodic induction accelerator units. Parameters are given for a full-size device and for an experimental device using the FEL at the ETA; namely the ELF Facility. 6 refs., 2 figs

Quasi-relativistic fermions and dynamical flavour oscillations

CERN Document Server

Alexandre, Jean; Mavromatos, Nick E.

2014-01-01

We introduce new Lorentz-symmetry violating kinematics for a four-fermion interaction model, where dynamical mass generation is allowed, irrespectively of the strength of the coupling. In addition, these kinematics lead to a quasi-relativistic dispersion relation, in the sense that it is relativistic in both the infrared and the ultraviolet, but not in an intermediate regime, characterized by the mass $M$. For two fermions, we show that a flavour-mixing mass matrix is generated dynamically, and the Lorentz symmetric limit $M\\to\\infty$ leads to two free relativistic fermions, with flavour oscillations. This model, valid for either Dirac or Majorana fermions, can describe any set of phenomenological values for the eigen masses and the mixing angle.

On the relativistic extended Thomas-Fermi method

International Nuclear Information System (INIS)

Centelles, M.; Vinas, X.; Barranco, M.; Schuck, P.

1990-01-01

We have derived the semiclassical relativistic energy functional for a set of fermions moving in the mean field arising from scalar and vector fields, including up to ℎ 2 corrective terms. The method is applied to a relativistic harmonic oscillator model for which the semiclassical result can be compared with the exact solution of the Dirac equation. (orig.)

On the relativistic extended Thomas-Fermi method

International Nuclear Information System (INIS)

Centelles, M.; Vinas, X.; Barranco, M.; Schuck, P.

1990-01-01

We have derived the semiclassical relativistic energy functional for a set of fermions moving in the mean field arising from scalar and vector fields, including up to ℎ 2 corrective terms. The method is applied to a relativistic harmonic oscillator model for which the semiclassical result can be compared with the exact solution of the Dirac equation

Low-momentum-transfer nonrelativistic limit of the relativistic impulse approximation expression for Compton-scattering doubly differential cross sections and characterization of their relativistic contributions

International Nuclear Information System (INIS)

LaJohn, L. A.

2010-01-01

The nonrelativistic (nr) impulse approximation (NRIA) expression for Compton-scattering doubly differential cross sections (DDCS) for inelastic photon scattering is recovered from the corresponding relativistic expression (RIA) of Ribberfors [Phys. Rev. B 12, 2067 (1975)] in the limit of low momentum transfer (q→0), valid even at relativistic incident photon energies ω 1 >m provided that the average initial momentum of the ejected electron i > is not too high, that is, i > b 1 >m using nr expressions when θ is small. For example, a 1% accuracy can be obtained when ω 1 =1 MeV if θ 1 increases into the MeV range, the maximum θ at which an accurate Compton peak can be obtained from nr expressions approaches closer to zero, because the θ at which the relativistic shift of CP to higher energy is greatest, which starts at 180 deg. when ω 1 min ,ρ rel ) (where p min is the relativistic version of the z component of the momentum of the initial electron and ρ rel is the relativistic charge density) and K(p min ) on p min . This characterization approach was used as a guide for making the nr QED S-matrix expression for the Compton peak kinematically relativistic. Such modified nr expressions can be more readily applied to large systems than the fully relativistic version.

Relativistic Coulomb excitation

International Nuclear Information System (INIS)

Winther, A.; Alder, K.

1979-01-01

Coulomb excitation of both target and projectile in relativistic heavy ion collisions is evaluated including the lowest order correction for the deviation from a straight line trajectory. Explicit results for differential and total cross sections are given in the form of tables and figures. (Auth.)

Radiative electron capture studied in relativistic heavy-ion atom collisions

International Nuclear Information System (INIS)

Stoehlker, T.; Kozhuharov, C.; Mokler, P.H.; Warczak, A.; Bosch, F.; Geissel, H.; Moshammer, R.; Scheidenberger, C.; Eichler, J.; Shirai, T.; Stachura, Z.; Rymuza, P.

1994-08-01

The process of Radiative Electron Capture (REC) in relativistic collisions of high-Z ions with low-Z gaseous and solid targets is studied experimentally and theoretically. The observed X-ray spectra are analysed with respect to photon angular distributions as well as to total K-REC cross sections. The experimental results for angle-differential cross sections are well-reproduced by exact relativistic calculations which yield significant deviations from standard sin 2 θ distributions. Total cross sections for K-REC are shown to follow a simple scaling rule obtained from exact relativistic calculations as well as from a non-relativistic dipole approximation. The agreement between these different theoretical approaches must be regarded as fortuitous, but it lends support to the use of the non-relativistic approach for practical purposes. (orig.)

Canonical analysis of non-relativistic particle and superparticle

Energy Technology Data Exchange (ETDEWEB)

Kluson, Josef [Masaryk University, Department of Theoretical Physics and Astrophysics, Faculty of Science, Brno (Czech Republic)

2018-02-15

We perform canonical analysis of non-relativistic particle in Newton-Cartan Background. Then we extend this analysis to the case of non-relativistic superparticle in the same background. We determine constraints structure of this theory and find generator of κ-symmetry. (orig.)

Methods in relativistic nuclear physics

International Nuclear Information System (INIS)

Danos, M.; Gillet, V.; Cauvin, M.

1984-01-01

This book is intended to provide the methods and tools for performing actual calculations for finite many-body systems of bound relativistic constituent particles. The aim is to cover thoroughly the methodological aspects of the relativistic many-body problem for bound states while avoiding the presentation of specific models. The many examples contained in the later part of the work are meant to give concrete illustrations of how to actually apply the methods which are given in the first part. The basic framework of the approach is the lagrangian field theory solved in the time-independent Schroedinger picture. (Auth.)

Fundamental problem in the relativistic approach to atomic structure theory

International Nuclear Information System (INIS)

Kagawa, Takashi

1987-01-01

It is known that the relativistic atomic structure theory contains a serious fundamental problem, so-called the Brown-Ravenhall (BR) problem or variational collapse. This problem arises from the fact that the energy spectrum of the relativistic Hamiltonian for many-electron systems is not bounded from below because the negative-energy solutions as well as the positive-energy ones are obtained from the relativistic equation. This report outlines two methods to avoid the BR problem in the relativistic calculation, that is, the projection operator method and the general variation method. The former method is described first. The use of a modified Hamiltonian containing a projection operator which projects the positive-energy solutions in the relativistic wave equation has been proposed to remove the BR difficulty. The problem in the use of the projection operator method is that the projection operator for the system cannot be determined uniquely. The final part of this report outlines the general variation method. This method can be applied to any system, such as relativistic ones whose Hamiltonian is not bounded from below. (Nogami, K.)

Relativistic particle in a box: Klein-Gordon versus Dirac equations

Science.gov (United States)

Alberto, Pedro; Das, Saurya; Vagenas, Elias C.

2018-03-01

The problem of a particle in a box is probably the simplest problem in quantum mechanics which allows for significant insight into the nature of quantum systems and thus is a cornerstone in the teaching of quantum mechanics. In relativistic quantum mechanics this problem allows also to highlight the implications of special relativity for quantum physics, namely the effect that spin has on the quantised energy spectra. To illustrate this point, we solve the problem of a spin zero relativistic particle in a one- and three-dimensional box using the Klein-Gordon equation in the Feshbach-Villars formalism. We compare the solutions and the energy spectra obtained with the corresponding ones from the Dirac equation for a spin one-half relativistic particle. We note the similarities and differences, in particular the spin effects in the relativistic energy spectrum. As expected, the non-relativistic limit is the same for both kinds of particles, since, for a particle in a box, the spin contribution to the energy is a relativistic effect.

Relativistic simulation of the Vlasov equation for plasma expansion into vacuum

Directory of Open Access Journals (Sweden)

H Abbasi

2012-12-01

Full Text Available   In this study, relativistic Vlasov simulation of plasma for expansion of collisionless plasma for into vacuum is presented. The model is based on 1+1 dimensional phase space and electrostatic approximation. For this purpose, the electron dynamics is studied by the relativistic Vlasov equation. Regardless of the ions temperature, fluid equations are used for their dynamics. The initial electrons distribution function is the relativistic Maxwellian. The results show that due to the electrons relativistic temperature, the process of the plasma expansion takes place faster, the resulting electric field is stronger and the ions are accelerated to higher velocities, in comparison to the non-relativistic case.

Relativistic thermodynamics and kinetic theory, with applications to cosmology

International Nuclear Information System (INIS)

Stewart, J.M.

1973-01-01

The discussion of relativistic thermodynamics and kinetic theory with applications to cosmology also covers the fundamentals and nonequilibrium relativistic kinetic theory and applications to cosmology and astrophysics. (U.S.)

Observational and theoretical aspects of relativistic astrophysics and cosmology

International Nuclear Information System (INIS)

Sanz, J.L.; Goicoechea, L.J.

1985-01-01

The studies of relativistic astrophysics and cosmology in these proceedings include primordial nucleosynthesis, nonluminous matter, star and galaxy evolution, cosmic microwave background, and general relativistic models of the universe

Relativistic stars in vector-tensor theories

Science.gov (United States)

Kase, Ryotaro; Minamitsuji, Masato; Tsujikawa, Shinji

2018-04-01

We study relativistic star solutions in second-order generalized Proca theories characterized by a U (1 )-breaking vector field with derivative couplings. In the models with cubic and quartic derivative coupling, the mass and radius of stars become larger than those in general relativity for negative derivative coupling constants. This phenomenon is mostly attributed to the increase of star radius induced by a slower decrease of the matter pressure compared to general relativity. There is a tendency that the relativistic star with a smaller mass is not gravitationally bound for a low central density and hence is dynamically unstable, but that with a larger mass is gravitationally bound. On the other hand, we show that the intrinsic vector-mode couplings give rise to general relativistic solutions with a trivial field profile, so the mass and radius are not modified from those in general relativity.

Relativistic Wigner functions

Directory of Open Access Journals (Sweden)

Bialynicki-Birula Iwo

2014-01-01

Full Text Available Original definition of the Wigner function can be extended in a natural manner to relativistic domain in the framework of quantum field theory. Three such generalizations are described. They cover the cases of the Dirac particles, the photon, and the full electromagnetic field.

The stability of ideal and resistive ballooning modes in the presence of equilibrium flows

International Nuclear Information System (INIS)

Sundaram, A.K.; Sen, A.

1989-01-01

Ideal and resistive ballooning modes have been the topic of extensive study in view of their important role in constraining plasma β or in causing degradation in electron energy confinement time. Much of these works in the literature have been done for static equilibrium. Recently several experiments on ISX, PDX and currently on TFTR and JET have demonstrated the presence of toroidal and poloidal flows due to asymmetry in the neutral beam injection (NBI). Also equilibrium flows can arise through diffusive processes in tokamak plasmas. Such flows induced by external sources or dissipative processes affect the form and location of the magnetic surfaces and also modify the density and pressure profiles in the equilibrium. In this paper, we therefore examine the effect of mass flows on the evolution of high (m,n) ideal and resistive ballooning modes using the simplified MHD equations. (author) 2 refs

Relativistic centrifugal instability

Science.gov (United States)

Gourgouliatos, Konstantinos N.; Komissarov, Serguei S.

2018-03-01

Near the central engine, many astrophysical jets are expected to rotate about their axis. Further out they are expected to go through the processes of reconfinement and recollimation. In both these cases, the flow streams along a concave surface and hence, it is subject to the centrifugal force. It is well known that such flows may experience the centrifugal instability (CFI), to which there are many laboratory examples. The recent computer simulations of relativistic jets from active galactic nuclei undergoing the process of reconfinement show that in such jets CFI may dominate over the Kelvin-Helmholtz instability associated with velocity shear (Gourgouliatos & Komissarov). In this letter, we generalize the Rayleigh criterion for CFI in rotating fluids to relativistic flows using a heuristic analysis. We also present the results of computer simulations which support our analytic criterion for the case of an interface separating two uniformly rotating cylindrical flows. We discuss the difference between CFI and the Rayleigh-Taylor instability in flows with curved streamlines.

Studying extremely peripheral collisions of relativistic heavy ions

International Nuclear Information System (INIS)

Fatyga, M.

1990-01-01

Relativistic heavy ion facilities have been proposed (and in some cases constructed) with an intent to search for a new state of matter, a quark gluon plasma. As with all tools in the experimental physics, one should always search for ways in which relativistic heavy ions can be used to study physical phenomena beyond this original goal. New possibilities for a study of higher order photonuclear excitations in extremely peripheral collisions of relativistic heavy ions are discussed in this contribution. Data on the electromagnetic and nuclear fragmentation of a 14.6Gev/nucleon 28 Si projectile are presented

Neutron relativistic phenomenological and microscopic optical potential

International Nuclear Information System (INIS)

Shen Qing-biao; Feng Da-chun; Zhuo Yi-zhong

1991-01-01

In this paper, both the phenomenological and microscopic neutron relativistic optical potentials are presented. The global neutron relativistic phenomenological optical potential (RPOP) based on the available experimental data for various nuclei ranging from C to U with incident energies E n =20--1000 MeV has been obtained through an automatic search of the best parameters by computer. Then the nucleon relativistic microscopic optical potential (RMOP) is studied by utilizing the effective Lagrangian based on the popular Walecka model. Through comparison between the theoretical results and experimental data we shed some insight into both the RMOP and RPOP. Further improvement concerning how to combine the phenomenological potential with the microscopic one in order to reduce the number of free parameters appearing in the RPOP is suggested

A relativistic, meson exchange model of pion-nucleon scattering

International Nuclear Information System (INIS)

Pearces, B.C.; Jennings, B.K.

1990-06-01

A relativistic meson exchange approach to the pion-nucleon interaction is developed using a three-dimensional relativistic two-body propagator, and the results using different propagators are compared. The relativistic approach is able to describe low energy scattering up to 400 MeV above threshold, while preserving the soft pion theorems. The different propagators give similar results, as the form factors necessary to get a fit suppress much of the multiple scattering. (Author) (24 refs., 4 tabs., 6 figs.)

On the dispersion characteristics of extraordinary mode in a relativistic fully degenerate electron plasma

Science.gov (United States)

Noureen, S.; Abbas, G.; Sarfraz, M.

2018-01-01

The study of relativistic degenerate plasmas is important in many astrophysical and laboratory environments. Using linearized relativistic Vlasov-Maxwell equations, a generalized expression for the plasma conductivity tensor is derived. Employing Fermi-Dirac distribution at zero temperature, the dispersion relation of the extraordinary mode in a relativistic degenerate electron plasma is investigated. The propagation characteristics are examined in different relativistic density ranges. The shifting of cutoff points due to relativistic effects is observed analytically and graphically. Non-relativistic and ultra-relativistic limiting cases are also presented.

Analytic study of 1D diffusive relativistic shock acceleration

Energy Technology Data Exchange (ETDEWEB)

Keshet, Uri, E-mail: ukeshet@bgu.ac.il [Physics Department, Ben-Gurion University of the Negev, POB 653, Be' er-Sheva 84105 (Israel)

2017-10-01

Diffusive shock acceleration (DSA) by relativistic shocks is thought to generate the dN / dE ∝ E{sup −p} spectra of charged particles in various astronomical relativistic flows. We show that for test particles in one dimension (1D), p {sup −1}=1−ln[γ{sub d}(1+β{sub d})]/ln[γ{sub u}(1+β{sub u})], where β{sub u}(β{sub d}) is the upstream (downstream) normalized velocity, and γ is the respective Lorentz factor. This analytically captures the main properties of relativistic DSA in higher dimensions, with no assumptions on the diffusion mechanism. Unlike 2D and 3D, here the spectrum is sensitive to the equation of state even in the ultra-relativistic limit, and (for a J(üttner-Synge equation of state) noticeably hardens with increasing 1<γ{sub u}<57, before logarithmically converging back to p (γ{sub u→∞})=2. The 1D spectrum is sensitive to drifts, but only in the downstream, and not in the ultra-relativistic limit.

Relativistic classical limit of quantum theory

International Nuclear Information System (INIS)

Shin, G.R.; Rafelski, J.

1993-01-01

We study the classical limit of the equal-time relativistic quantum transport theory. We discuss in qualitative terms the need to fold first the Wigner function with a coarse-graining function. Only then does the singularity at ℎ→0 seem to be manageable. In the limit ℎ→0, we obtain the relativistic Vlasov equations for the particle and the antiparticle sector of the Fock space. Similarly, we address the evolution equations of the spin and the magnetic-moment density

In-vacuum sensors for the beamline components of the ITER neutral beam test facility

Energy Technology Data Exchange (ETDEWEB)

Dalla Palma, M., E-mail: mauro.dallapalma@igi.cnr.it; Pasqualotto, R.; Spagnolo, S.; Spolaore, M. [Consorzio RFX, Padova 35127 (Italy); Sartori, E. [Consorzio RFX, Padova 35127 (Italy); Università degli Studi di Padova, Padova 35122 (Italy); Veltri, P. [Consorzio RFX, Padova 35127 (Italy); INFN-LNL, Legnaro (PD) 35020 (Italy)

2016-11-15

Embedded sensors have been designed for installation on the components of the MITICA beamline, the prototype ITER neutral beam injector (Megavolt ITER Injector and Concept Advancement), to derive characteristics of the particle beam and to monitor the component conditions during operation for protection and thermal control. Along the beamline, the components interacting with the particle beam are the neutralizer, the residual ion dump, and the calorimeter. The design and the positioning of sensors on each component have been developed considering the expected beam-surface interaction including non-ideal and off-normal conditions. The arrangement of the following instrumentation is presented: thermal sensors, strain gages, electrostatic probes including secondary emission detectors, grounding shunt for electrical currents, and accelerometers.

Relativistic and Non-Relativistic Electronic Molecular-Structure Calculations for Dimers of 4p-, 5p-, and 6p-Block Elements

DEFF Research Database (Denmark)

Hofener, S.; Ahlrichs, R.; Knecht, S.

2012-01-01

We report results of non-relativistic and two-component relativistic single-reference coupled-cluster with single and double and perturbative triple excitations [CCSD(T)] treatments for the 4p-block dimers Ga2 to Br2, the 5p-block dimers In2 to I2, and their atoms. Extended basis sets up...

Relativistic beaming and quasar statistics

International Nuclear Information System (INIS)

Orr, M.J.L.; Browne, I.W.A.

1982-01-01

The statistical predictions of a unified scheme for the radio emission from quasars are explored. This scheme attributes the observed differences between flat- and steep-spectrum quasars to projection and the effects of relativistic beaming of the emission from the nuclear components. We use a simple quasar model consisting of a compact relativistically beamed core with spectral index zero and unbeamed lobes, spectral index - 1, to predict the proportion of flat-spectrum sources in flux-limited samples selected at different frequencies. In our model this fraction depends on the core Lorentz factor, γ and we find that a value of approximately 5 gives satisfactory agreement with observation. In a similar way the model is used to construct the expected number/flux density counts for flat-spectrum quasars from the observed steep-spectrum counts. Again, good agreement with the observations is obtained if the average core Lorentz factor is about 5. Independent estimates of γ from observations of superluminal motion in quasars are of the same order of magnitude. We conclude that the statistical properties of quasars are entirely consistent with the predictions of simple relativistic-beam models. (author)

Relativistic studies in actinides

International Nuclear Information System (INIS)

Weinberger, P.; Gonis, A.

1987-01-01

In this review the theoretical background is given for a relativistic description for actinide systems. A short introduction is given of the density functional theory which forms the basis for a fully relativistic single-particle theory. A section on the Dirac Hamiltonian is followed by a brief summary on group theoretical concepts. Single site scattering is presented such that formal extensions to the case of the presence of an internal (external) magnetic field and/or anisotropic scattering are evident. Multiple scattering is discussed such that it can readily be applied also to the problem of dislocations. In connection with the problem of selfconsistency particular attention is drawn to the use of complex energies. Finally the various theoretical aspects discussed are illustrated through the results of numerical calculations. 101 refs.; 37 figs.; 5 tabs

Relativistic supersymmetric quantum mechanics based on Klein-Gordon equation

International Nuclear Information System (INIS)

Znojil, Miloslav

2004-01-01

Witten's the non-relativistic formalism of supersymmetric quantum mechanics was based on a factorization and partnership between Schroedinger equations. We show how it accommodates a transition to the partnership between relativistic Klein-Gordon equations

Ionization of hydrogen by a relativistic heavy projectile

International Nuclear Information System (INIS)

Hofstetter, S.; Hofmann, C.; Soff, G.

1991-10-01

Using a relativistic analogue of the classical trajectory Monte-Carlo method we investigate the influence of the magnetic field of a relativistic heavy projectile on the ionization cross section of hydrogen. In particular we focus our attention on the angular and energy distribution of the emitted delta electrons. (orig.)

Particle Acceleration and Radiative Losses at Relativistic Shocks

Science.gov (United States)

Dempsey, P.; Duffy, P.

A semi-analytic approach to the relativistic transport equation with isotropic diffusion and consistent radiative losses is presented. It is based on the eigenvalue method first introduced in Kirk & Schneider [5]and Heavens & Drury [3]. We demonstrate the pitch-angle dependence of the cut-off in relativistic shocks.

SPECIAL RELATIVISTIC HYDRODYNAMICS WITH GRAVITATION

Energy Technology Data Exchange (ETDEWEB)

Hwang, Jai-chan [Department of Astronomy and Atmospheric Sciences, Kyungpook National University, Daegu (Korea, Republic of); Noh, Hyerim [Korea Astronomy and Space Science Institute, Daejon (Korea, Republic of)

2016-12-20

Special relativistic hydrodynamics with weak gravity has hitherto been unknown in the literature. Whether such an asymmetric combination is possible has been unclear. Here, the hydrodynamic equations with Poisson-type gravity, considering fully relativistic velocity and pressure under the weak gravity and the action-at-a-distance limit, are consistently derived from Einstein’s theory of general relativity. An analysis is made in the maximal slicing, where the Poisson’s equation becomes much simpler than our previous study in the zero-shear gauge. Also presented is the hydrodynamic equations in the first post-Newtonian approximation, now under the general hypersurface condition. Our formulation includes the anisotropic stress.

Pivotal issues on relativistic electrons in ITER

Science.gov (United States)

Boozer, Allen H.

2018-03-01

The transfer of the plasma current from thermal to relativistic electrons is a threat to ITER achieving its mission. This danger is significantly greater in the nuclear than in the non-nuclear phase of ITER operations. Two issues are pivotal. The first is the extent and duration of magnetic surface breaking in conjunction with the thermal quenches. The second is the exponential sensitivity of the current transfer to three quantities: (1) the poloidal flux change required to e-fold the number of relativistic electrons, (2) the time τa after the beginning of the thermal quench before the accelerating electric field exceeds the Connor-Hastie field for runaway, and (3) the duration of the period τ_op in which magnetic surfaces remain open. Adequate knowledge does not exist to devise a reliable strategy for the protection of ITER. Uncertainties are sufficiently large that a transfer of neither a negligible nor the full plasma current to relativistic electrons can be ruled out during the non-nuclear phase of ITER. Tritium decay can provide a sufficiently strong seed for a dangerous relativistic-electron current even if τa and τ_op are sufficiently long to avoid relativistic electrons during non-nuclear operations. The breakup of magnetic surfaces that is associated with thermal quenches occurs on a time scale associated with fast magnetic reconnection, which means reconnection at an Alfvénic rather than a resistive rate. Alfvénic reconnection is well beyond the capabilities of existing computational tools for tokamaks, but its effects can be studied using its property of conserving magnetic helicity. Although the dangers to ITER from relativistic electrons have been known for twenty years, the critical issues have not been defined with sufficient precision to formulate an effective research program. Studies are particularly needed on plasma behavior in existing tokamaks during thermal quenches, behavior which could be clarified using methods developed here.

Ideals in algebras of unbounded operators

International Nuclear Information System (INIS)

Timmermann, W.

1977-01-01

The paper presents a continuation of investigations on ideals in algebras of unbounded operators. A general procedure is given to get ideals in L + (D) starting with ideals in B(H). A definition of the two types of ideals is given: one contains only bounded operators, the other involves both bounded and unbounded operators. Some algebraic properties of ideals Ssub(phi)(D) derived from the well-known symmetrically normed ideals Ssub(phi) are investigated. Topologies in such ideals are introduced, and some results connected with topological properties of these ideals are given

Selectivity of the nucleon-induced deuteron breakup and relativistic effects

OpenAIRE

Witała, H.; Golak, J.; Skibiński, R.

2006-01-01

Theoretical predictions for the nucleon induced deuteron breakup process based on solutions of the three-nucleon Faddeev equation including such relativistic features as the relativistic kinematics and boost effects are presented. Large changes of the breakup cross section in some complete configurations are found at higher energies. The predicted relativistic effects, which are mostly of dynamical origin, seem to be supported by existing data.

On the time delay between ultra-relativistic particles

Energy Technology Data Exchange (ETDEWEB)

Fleury, Pierre, E-mail: pierre.fleury@uct.ac.za [Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701, Cape Town (South Africa); Department of Physics, University of the Western Cape, Robert Sobukwe Road, Bellville 7535 (South Africa)

2016-09-10

The time delay between the receptions of ultra-relativistic particles emitted simultaneously is a useful observable for both fundamental physics and cosmology. The expression of the delay when the particles travel through an arbitrary spacetime has been derived recently by Fanizza et al., using a particular coordinate system and self-consistent assumptions. The present article shows that this formula enjoys a simple physical interpretation: the relative velocity between two ultra-relativistic particles is constant. This result reveals an interesting kinematical property of general relativity, namely that the tidal forces experienced by ultra-relativistic particles in the direction of their motion are much smaller than those experienced orthogonally to their motion.

On the time delay between ultra-relativistic particles

International Nuclear Information System (INIS)

Fleury, Pierre

2016-01-01

The time delay between the receptions of ultra-relativistic particles emitted simultaneously is a useful observable for both fundamental physics and cosmology. The expression of the delay when the particles travel through an arbitrary spacetime has been derived recently by Fanizza et al., using a particular coordinate system and self-consistent assumptions. The present article shows that this formula enjoys a simple physical interpretation: the relative velocity between two ultra-relativistic particles is constant. This result reveals an interesting kinematical property of general relativity, namely that the tidal forces experienced by ultra-relativistic particles in the direction of their motion are much smaller than those experienced orthogonally to their motion.

Relativistic spin precession in the double pulsar.

Science.gov (United States)

Breton, Rene P; Kaspi, Victoria M; Kramer, Michael; McLaughlin, Maura A; Lyutikov, Maxim; Ransom, Scott M; Stairs, Ingrid H; Ferdman, Robert D; Camilo, Fernando; Possenti, Andrea

2008-07-04

The double pulsar PSR J0737-3039A/B consists of two neutron stars in a highly relativistic orbit that displays a roughly 30-second eclipse when pulsar A passes behind pulsar B. Describing this eclipse of pulsar A as due to absorption occurring in the magnetosphere of pulsar B, we successfully used a simple geometric model to characterize the observed changing eclipse morphology and to measure the relativistic precession of pulsar B's spin axis around the total orbital angular momentum. This provides a test of general relativity and alternative theories of gravity in the strong-field regime. Our measured relativistic spin precession rate of 4.77 degrees (-0 degrees .65)(+0 degrees .66) per year (68% confidence level) is consistent with that predicted by general relativity within an uncertainty of 13%.

Numerical solution of ordinary differential equations. For classical, relativistic and nano systems

International Nuclear Information System (INIS)

Greenspan, D.

2006-01-01

An up-to-date survey on numerical solutions with theory, intuition and applications. Ordinary differential equations (ODE) play a significant role in mathematics, physics and engineering sciences, and thus are part of relevant college and university courses. Many problems, however, both traditional and modern, do not possess exact solutions, and must be treated numerically. Usually this is done with software packages, but for this to be efficient requires a sound understanding of the mathematics involved. This work meets the need for an affordable textbook that helps in understanding numerical solutions of ODE. Carefully structured by an experienced textbook author, it provides a survey of ODE for various applications, both classical and modern, including such special applications as relativistic and nano systems. The examples are carefully explained and compiled into an algorithm, each of which is presented generically, independent of a specific programming language, while each chapter is rounded off with exercises. The text meets the demands of MA200 courses and of the newly created Numerical Solution of Differential Equations courses, making it ideal for both students and lecturers in physics, mathematics, mechanical engineering, electrical engineering, as well as for physicists, mathematicians, engineers, and electrical engineers. From the Contents - Euler's Method - Runge-Kutta Methods - The Method of Taylor Expansions - Large Second Order Systems with Application to Nano Systems - Completely Conservative, Covariant Numerical Methodology - Instability - Numerical Solution of Tridiagonal Linear Algebraic Systems and Related Nonlinear Systems - Approximate Solution of Boundary Value Problems - Special Relativistic Motion - Special Topics - Appendix: Basic Matrix Operations - Bibliography. (orig.) (orig.)

Improved DEA Cross Efficiency Evaluation Method Based on Ideal and Anti-Ideal Points

Directory of Open Access Journals (Sweden)

Qiang Hou

2018-01-01

Full Text Available A new model is introduced in the process of evaluating efficiency value of decision making units (DMUs through data envelopment analysis (DEA method. Two virtual DMUs called ideal point DMU and anti-ideal point DMU are combined to form a comprehensive model based on the DEA method. The ideal point DMU is taking self-assessment system according to efficiency concept. The anti-ideal point DMU is taking other-assessment system according to fairness concept. The two distinctive ideal point models are introduced to the DEA method and combined through using variance ration. From the new model, a reasonable result can be obtained. Numerical examples are provided to illustrate the new constructed model and certify the rationality of the constructed model through relevant analysis with the traditional DEA model.

Modeling terrestrial gamma ray flashes produced by relativistic feedback discharges

Science.gov (United States)

Liu, Ningyu; Dwyer, Joseph R.

2013-05-01

This paper reports a modeling study of terrestrial gamma ray flashes (TGFs) produced by relativistic feedback discharges. Terrestrial gamma ray flashes are intense energetic radiation originating from the Earth's atmosphere that has been observed by spacecraft. They are produced by bremsstrahlung interactions of energetic electrons, known as runaway electrons, with air atoms. An efficient physical mechanism for producing large fluxes of the runaway electrons to make the TGFs is the relativistic feedback discharge, where seed runaway electrons are generated by positrons and X-rays, products of the discharge itself. Once the relativistic feedback discharge becomes self-sustaining, an exponentially increasing number of relativistic electron avalanches propagate through the same high-field region inside the thundercloud until the electric field is partially discharged by the ionization created by the discharge. The modeling results indicate that the durations of the TGF pulses produced by the relativistic feedback discharge vary from tens of microseconds to several milliseconds, encompassing all durations of the TGFs observed so far. In addition, when a sufficiently large potential difference is available in thunderclouds, a self-propagating discharge known as the relativistic feedback streamer can be formed, which propagates like a conventional positive streamer. For the relativistic feedback streamer, the positive feedback mechanism of runaway electron production by the positrons and X-rays plays a similar role as the photoionization for the conventional positive streamer. The simulation results of the relativistic feedback streamer show that a sequence of TGF pulses with varying durations can be produced by the streamer. The relativistic streamer may initially propagate with a pulsed manner and turn into a continuous propagation mode at a later stage. Milliseconds long TGF pulses can be produced by the feedback streamer during its continuous propagation. However

Non-relativistic supersymmetry

International Nuclear Information System (INIS)

Clark, T.E.; Love, S.T.

1984-01-01

The most general one- and two-body hamiltonian invariant under galilean supersymmetry is constructed in superspace. The corresponding Feynman rules are given for the superfield Green functions. As demonstrated by a simple example, it is straightforward to construct models in which the supersymmetry is spontaneously broken by the non-relativistic vacuum. (orig.)

The Relativistic Rocket

Science.gov (United States)

Antippa, Adel F.

2009-01-01

We solve the problem of the relativistic rocket by making use of the relation between Lorentzian and Galilean velocities, as well as the laws of superposition of successive collinear Lorentz boosts in the limit of infinitesimal boosts. The solution is conceptually simple, and technically straightforward, and provides an example of a powerful…

Relativistic klystron research at SLAC and LLNL

International Nuclear Information System (INIS)

Allen, M.A.; Callin, R.S.; Deruyter, H.

1988-06-01

We are developing relativistic klystrons as a power source for high gradient accelerator applications such as large linear electron-positron colliders and compact accelerators. We have attained 200 MW peak power at 11.4 GHz from a relativistic klystron, and 140 MV/m longitudinal gradient in a short 11.4 GHz accelerator section. We report here briefly on our experiments so far. 5 refs., 1 fig., 1 tab

Dechanneling function for relativistic axially channeled electrons

International Nuclear Information System (INIS)

Muralev, V.A.; Telegin, V.I.

1981-01-01

Behaviour of the x(t) dechanneling function depending on the depth is theoretically studied. Theoretical consideration of x(t) for axial channeled relativistic electrons in anisotropic medium results in two-dimensional kinetic equation with mixed derivatives of the parabolic type. The kinetic equation in the approximation of the continuous Lindchard model for relativistic axial channeled electrons is numerically solved. The depth dependence of the x(t) dechanneling function is obtained [ru

Relativistic quantum mechanics an introduction to relativistic quantum fields

CERN Document Server

Maiani, Luciano

2016-01-01

Written by two of the world's leading experts on particle physics and the standard model - including an award-winning former Director General of CERN - this textbook provides a completely up-to-date account of relativistic quantum mechanics and quantum field theory. It describes the formal and phenomenological aspects of the standard model of particle physics, and is suitable for advanced undergraduate and graduate students studying both theoretical and experimental physics.

Relativistic beaming and orientation effects in core-dominated quasars

International Nuclear Information System (INIS)

Ubachukwu, A.A.; Chukwude, A.E.

2002-07-01

In this paper, we investigate the relativistic beaming effects in a well-defined sample of core- dominated quasars using the correlation between the relative prominence of the core with respect to the extended emission (defined as the ratio of the core- to the lobe- flux density measured in the rest frame of the source) and the projected linear size as an indicator of relativistic beaming and source orientation. Based on the orientation-dependent relativistic beaming and unification paradigm for high luminosity sources in which the Fanaroff-Riley class-ll radio galaxies form the unbeamed parent population of both the lobe- and core-dominated quasars which are expected to lie at successively smaller angles to the line of sight, we find that the flows in the cores of these core-dominated quasars are highly relativistic, with optimum bulk Lorentz factor, γ opt ∼6-16, and also highly anisotropic, with an average viewing angle, ∼ 9 deg. - 16 deg. Furthermore, the largest boosting occurs within a critical cone angle of ∼ 4 deg. - 10 deg. The results suggest that relativistic bulk flow appears to extend to kilo-parsec scales in these sources. (author)

On becoming neutral: effects of experimental neutralizing reconsidered.

Science.gov (United States)

van den Hout, M; van Pol, M; Peters, M

2001-12-01

Behaviour Research and Therapy 34 (1996) 889-898 found that writing out a negative thought produced anxiety and an urge to neutralize the thought, that instructing participants to neutralize the thought reduced anxiety/neutralization urge in the short run (i.e. within 2 min), but that in the control group 20 min without instruction was attended by the same reduction in anxiety/urge to neutralize ("natural decay"). The observations were made with pariticipants who scored high on "thought action fusion" and the experiment was set up as exerimental model of obsessions. We repeated the study with participants that were not selected on thought action fusion. All the findings reported by Behaviour Research and Therapy 34 (1996) 889-898 were replicated. Correlational analysis indicated that the strength of the effect was not related to scores on scales measuring "thought action fusion". Behaviour Research and Therapy 34 (1996) 889-898 did not assess whether non-neutralizing was followed by immediate reductions in distress. We did assess this and found that the larger part of the immediate reduction of distress after neutralization also occurs when no neutralization instruction is given. The effects of neutralization instructions in the present type of experiment are considerably less powerful than suggested earlier.

Ion-acoustic envelope modes in a degenerate relativistic electron-ion plasma

Energy Technology Data Exchange (ETDEWEB)

McKerr, M.; Kourakis, I. [Centre for Plasma Physics, School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN Belfast, Northern Ireland (United Kingdom); Haas, F. [Instituto de Física, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, Porto Alegre, RS (Brazil)

2016-05-15

A self-consistent relativistic two-fluid model is proposed for one-dimensional electron-ion plasma dynamics. A multiple scales perturbation technique is employed, leading to an evolution equation for the wave envelope, in the form of a nonlinear Schrödinger type equation (NLSE). The inclusion of relativistic effects is shown to introduce density-dependent factors, not present in the non-relativistic case—in the conditions for modulational instability. The role of relativistic effects on the linear dispersion laws and on envelope soliton solutions of the NLSE is discussed.

Relativistic kinetic theory with applications in astrophysics and cosmology

CERN Document Server

Vereshchagin, Gregory V

2017-01-01

Relativistic kinetic theory has widespread application in astrophysics and cosmology. The interest has grown in recent years as experimentalists are now able to make reliable measurements on physical systems where relativistic effects are no longer negligible. This ambitious monograph is divided into three parts. It presents the basic ideas and concepts of this theory, equations and methods, including derivation of kinetic equations from the relativistic BBGKY hierarchy and discussion of the relation between kinetic and hydrodynamic levels of description. The second part introduces elements of computational physics with special emphasis on numerical integration of Boltzmann equations and related approaches, as well as multi-component hydrodynamics. The third part presents an overview of applications ranging from covariant theory of plasma response, thermalization of relativistic plasma, comptonization in static and moving media to kinetics of self-gravitating systems, cosmological structure formation and neut...

Mathematics and geometry towards ideality in «Domus»’s ideal houses

Directory of Open Access Journals (Sweden)

Simona Chiodo

2018-01-01

Full Text Available Between 1942 and 1943 the editor of the journal «Domus» invited the most important Italian architects to design their ideal houses: fifteen projects designed by seventeen architects were published. They are most instructive to try to understand, firstly, what the philosophical notion of ideal means and, secondly, why mathematical and geometric tools are extensively used to work on ideality, namely, to design ideal houses. The first part of the article focuses on the philosophical foundations of ideality and, after an overview of the fifteen projects, on the use of the golden ratio in two particularly meaningful cases. The second part of the article focuses on the cases in which there is a hidden use of the golden ratio, on the use of the modulus and on the use of the number 2.

Relativistic multiple scattering X-alpha calculations

International Nuclear Information System (INIS)

Chermette, H.; Goursot, A.

1986-01-01

The necessity to include self-consistent relativistic corrections in molecular calculations has been pointed out for all compounds involving heavy atoms. Most of the changes in the electronic properties are due to the mass-velocity and the so-called Darwin terms so that the use of Wood and Boring's Hamiltonian is very convenient for this purpose as it can be easily included in MSXalpha programs. Although the spin orbit operator effects are only obtained by perturbation theory, the results compare fairly well with experiment and with other relativistic calculations, namely Hartree-Fock-Slater calculations

Cosmic anisotropy with reduced relativistic gas

Energy Technology Data Exchange (ETDEWEB)

Castardelli dos Reis, Simpliciano [Universidade Federal de Juiz de Fora, Departamento de Fisica, ICE, Juiz de Fora, MG (Brazil); Shapiro, Ilya L. [Universidade Federal de Juiz de Fora, Departamento de Fisica, ICE, Juiz de Fora, MG (Brazil); Tomsk State Pedagogical University, Tomsk (Russian Federation); Tomsk State University, Tomsk (Russian Federation)

2018-02-15

The dynamics of cosmological anisotropies is investigated for Bianchi type I universe filled by a relativistic matter represented by the reduced relativistic gas model (RRG), with equation of state interpolating between radiation and matter. Previously it was shown that the interpolation is observed in the background cosmological solutions for homogeneous and isotropic universe and also for the linear cosmological perturbations. We extend the application of RRG to the Bianchi type I anisotropic model and find that the solutions evolve to the isotropic universe with the pressureless matter contents. (orig.)

The relativistic mean-field description of nuclei and nuclear dynamics

International Nuclear Information System (INIS)

Reinhard, P.G.

1989-01-01

The relativistic mean-field model of the nucleus is reviewed. It describes the nucleus as a system of Dirac-Nucleons which interact in a relativistic covariant manner via meson fields. The meson fields are treated as mean fields, i.e. as non quantal c-number fields. The effects of the Dirac sea of the nucleons is neglected. The model is interpreted as a phenomenological ansatz providing a selfconsistent relativistic description of nuclei and nuclear dynamics. It is viewed, so to say, as the relativistic generalisation of the Skyrme-Hartree-Fock ansatz. The capability and the limitations of the model to describe nuclear properties are discussed. Recent applications to spherical and deformed nuclei and to nuclear dynamics are presented. (orig.)

Relativistic n-body wave equations in scalar quantum field theory

International Nuclear Information System (INIS)

Emami-Razavi, Mohsen

2006-01-01

The variational method in a reformulated Hamiltonian formalism of Quantum Field Theory (QFT) is used to derive relativistic n-body wave equations for scalar particles (bosons) interacting via a massive or massless mediating scalar field (the scalar Yukawa model). Simple Fock-space variational trial states are used to derive relativistic n-body wave equations. The equations are shown to have the Schroedinger non-relativistic limits, with Coulombic interparticle potentials in the case of a massless mediating field and Yukawa interparticle potentials in the case of a massive mediating field. Some examples of approximate ground state solutions of the n-body relativistic equations are obtained for various strengths of coupling, for both massive and massless mediating fields

The relativistic gravity train

Science.gov (United States)

Seel, Max

2018-05-01

The gravity train that takes 42.2 min from any point A to any other point B that is connected by a straight-line tunnel through Earth has captured the imagination more than most other applications in calculus or introductory physics courses. Brachystochron and, most recently, nonlinear density solutions have been discussed. Here relativistic corrections are presented. It is discussed how the corrections affect the time to fall through Earth, the Sun, a white dwarf, a neutron star, and—the ultimate limit—the difference in time measured by a moving, a stationary and the fiducial observer at infinity if the density of the sphere approaches the density of a black hole. The relativistic gravity train can serve as a problem with approximate and exact analytic solutions and as numerical exercise in any introductory course on relativity.

Relativistic three-particle dynamical equations: II. Application to the trinucleon system

International Nuclear Information System (INIS)

Adhikari, S.K.; Tomio, L.

1993-11-01

The contribution of relativistic dynamics on the neutron-deuteron scattering length and triton binding energy is calculated employing five sets tri nucleon potential models and four types of three-dimensional relativistic three-body equations suggested in the preceding paper. The relativistic correction to binding energy may vary a lot and even change sign depending on the relativistic formulation employed. The deviations of these observables from those obtained in nonrelativistic models follow the general universal trend of deviations introduced by off- and on-shell variations of two- and three-nucleon potentials in a nonrelativistic model calculation. Consequently, it will be difficult to separate unambiguously the effect of off-and on-shell variations of two and three-nucleon potentials on low-energy three-nucleon observables from the effect of relativistic dynamics. (author)

Medical ethics and more: ideal theories, non-ideal theories and conscientious objection.

Science.gov (United States)

Luna, Florencia

2015-01-01

Doing 'good medical ethics' requires acknowledgment that it is often practised in non-ideal circumstances! In this article I present the distinction between ideal theory (IT) and non-ideal theory (NIT). I show how IT may not be the best solution to tackle problems in non-ideal contexts. I sketch a NIT framework as a useful tool for bioethics and medical ethics and explain how NITs can contribute to policy design in non-ideal circumstances. Different NITs can coexist and be evaluated vis-à-vis the IT. Additionally, I address what an individual doctor ought to do in this non-ideal context with the view that knowledge of NITs can facilitate the decision-making process. NITs help conceptualise problems faced in the context of non-compliance and scarcity in a better and more realistic way. Deciding which policy is optimal in such contexts may influence physicians' decisions regarding their patients. Thus, this analysis-usually identified only with policy making-may also be relevant to medical ethics. Finally, I recognise that this is merely a first step in an unexplored but fundamental theoretical area and that more work needs to be done. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Origin of CH+ in diffuse molecular clouds. Warm H2 and ion-neutral drift

Science.gov (United States)

Valdivia, Valeska; Godard, Benjamin; Hennebelle, Patrick; Gerin, Maryvonne; Lesaffre, Pierre; Le Bourlot, Jacques

2017-04-01

Context. Molecular clouds are known to be magnetised and to display a turbulent and complex structure where warm and cold phases are interwoven. The turbulent motions within molecular clouds transport molecules, and the presence of magnetic fields induces a relative velocity between neutrals and ions known as the ion-neutral drift (vd). These effects all together can influence the chemical evolution of the clouds. Aims: This paper assesses the roles of two physical phenomena which have previously been invoked to boost the production of CH+ under realistic physical conditions: the presence of warm H2 and the increased formation rate due to the ion-neutral drift. Methods: We performed ideal magnetohydrodynamical (MHD) simulations that include the heating and cooling of the multiphase interstellar medium (ISM), and where we treat dynamically the formation of the H2 molecule. In a post-processing step we compute the abundances of species at chemical equilibrium using a solver that we developed. The solver uses the physical conditions of the gas as input parameters, and can also prescribe the H2 fraction if needed. We validate our approach by showing that the H2 molecule generally has a much longer chemical evolution timescale compared to the other species. Results: We show that CH+ is efficiently formed at the edge of clumps, in regions where the H2 fraction is low (0.3-30%) but nevertheless higher than its equilibrium value, and where the gas temperature is high (≳ 300 K). We show that warm and out of equilibrium H2 increases the integrated column densities of CH+ by one order of magnitude up to values still 3-10 times lower than those observed in the diffuse ISM. We balance the Lorentz force with the ion-neutral drag to estimate the ion-drift velocities from our ideal MHD simulations. We find that the ion-neutral drift velocity distribution peaks around 0.04 km s-1, and that high drift velocities are too rare to have a significant statistical impact on the

Monomial ideals, computations and applications

CERN Document Server

Gimenez, Philippe; Sáenz-de-Cabezón, Eduardo

2013-01-01

This work covers three important aspects of monomials ideals in the three chapters "Stanley decompositions" by Jürgen Herzog, "Edge ideals" by Adam Van Tuyl and "Local cohomology" by Josep Álvarez Montaner. The chapters, written by top experts, include computer tutorials that emphasize the computational aspects of the respective areas. Monomial ideals and algebras are, in a sense, among the simplest structures in commutative algebra and the main objects of combinatorial commutative algebra. Also, they are of major importance for at least three reasons. Firstly, Gröbner basis theory allows us to treat certain problems on general polynomial ideals by means of monomial ideals. Secondly, the combinatorial structure of monomial ideals connects them to other combinatorial structures and allows us to solve problems on both sides of this correspondence using the techniques of each of the respective areas. And thirdly, the combinatorial nature of monomial ideals also makes them particularly well suited to the devel...

Second Order Ideal-Ward Continuity

Directory of Open Access Journals (Sweden)

Bipan Hazarika

2014-01-01

Full Text Available The main aim of the paper is to introduce a concept of second order ideal-ward continuity in the sense that a function f is second order ideal-ward continuous if I-limn→∞Δ2f(xn=0 whenever I-limn→∞Δ2xn=0 and a concept of second order ideal-ward compactness in the sense that a subset E of R is second order ideal-ward compact if any sequence x=(xn of points in E has a subsequence z=(zk=(xnk of the sequence x such that I-limk→∞Δ2zk=0 where Δ2zk=zk+2-2zk+1+zk. We investigate the impact of changing the definition of convergence of sequences on the structure of ideal-ward continuity in the sense of second order ideal-ward continuity and compactness of sets in the sense of second order ideal-ward compactness and prove related theorems.

Axial motion of collector plasma in a relativistic backward wave oscillator

Energy Technology Data Exchange (ETDEWEB)

Xiao, Renzhen; Chen, Changhua; Deng, Yuqun; Cao, Yibing; Sun, Jun; Li, Jiawei [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi' an 710024 (China)

2016-06-15

In this paper, it is proposed that plasma formed at the collector may drift back to the cathode and cause pulse shortening of the relativistic backward wave oscillator. Theoretical analysis shows that the axial drift velocity of plasma ions can be up to 5 mm/ns due to the presence of space charge potential provided by an intense relativistic electron beam. Particle-in-cell simulations indicate that the plasma electrons are initially trapped around the collector surface. With the accumulation of the plasma ions, a large electrostatic field forms and drives the plasma electrons to overcome the space charge potential and enter the beam-wave interaction region along the magnetic field lines. As a result, the beam current modulation is disturbed and the output microwave power falls rapidly. The plasma ions move in the beam-wave interaction region with an average axial velocity of 5–8 mm/ns. After the plasma ions reach the diode region, the emitted current at the cathode rises due to the charge neutralizations by the ions. The impedance collapse leads to further decrease of the microwave power. In experiments, when the diode voltage and beam current were 850 kV and 9.2 kA, and the collector radius was 2.15 cm, the output microwave power was 2.4 GW with a pulse width of less than 20 ns. The ion drift velocity was estimated to be about 5 mm/ns. After an improved collector with 3.35 cm radius was adopted, the pulse width was prolonged to more than 30 ns.

Relativistic helicity and link in Minkowski space-time

International Nuclear Information System (INIS)

Yoshida, Z.; Kawazura, Y.; Yokoyama, T.

2014-01-01

A relativistic helicity has been formulated in the four-dimensional Minkowski space-time. Whereas the relativistic distortion of space-time violates the conservation of the conventional helicity, the newly defined relativistic helicity conserves in a barotropic fluid or plasma, dictating a fundamental topological constraint. The relation between the helicity and the vortex-line topology has been delineated by analyzing the linking number of vortex filaments which are singular differential forms representing the pure states of Banach algebra. While the dimension of space-time is four, vortex filaments link, because vorticities are primarily 2-forms and the corresponding 2-chains link in four dimension; the relativistic helicity measures the linking number of vortex filaments that are proper-time cross-sections of the vorticity 2-chains. A thermodynamic force yields an additional term in the vorticity, by which the vortex filaments on a reference-time plane are no longer pure states. However, the vortex filaments on a proper-time plane remain to be pure states, if the thermodynamic force is exact (barotropic), thus, the linking number of vortex filaments conserves

Solution of relativistic quantum optics problems using clusters of graphical processing units

Energy Technology Data Exchange (ETDEWEB)

Gordon, D.F., E-mail: daviel.gordon@nrl.navy.mil; Hafizi, B.; Helle, M.H.

2014-06-15

Numerical solution of relativistic quantum optics problems requires high performance computing due to the rapid oscillations in a relativistic wavefunction. Clusters of graphical processing units are used to accelerate the computation of a time dependent relativistic wavefunction in an arbitrary external potential. The stationary states in a Coulomb potential and uniform magnetic field are determined analytically and numerically, so that they can used as initial conditions in fully time dependent calculations. Relativistic energy levels in extreme magnetic fields are recovered as a means of validation. The relativistic ionization rate is computed for an ion illuminated by a laser field near the usual barrier suppression threshold, and the ionizing wavefunction is displayed.

Relativistic many-body bound systems. Monograph report

International Nuclear Information System (INIS)

Danos, M.; Gillet, V.

1975-04-01

The principles and the mathematical details of a fully relativistic nuclear theory are given. Since the concept of nuclear forces is a strictly non-relativistic construct, it must be abandoned, and the forces must be replaced explicitly by their physical origin, i.e., by the interaction between nucleons and mesons. Thus, in this monograph the description of a nucleus has been formulated as a problem of relativistic quantum field theory which is solved by nuclear physics methods; to wit: the physics is described by specifying a Lagrangian which is a functional of the constituent fields (= of the parton fields); the solutions for the physical systems then are obtained in a time-independent treatment as expansions in the parton fields: both particles and nuclei are composite systems, made up of parton configurations, which define a representation of the Hamiltonian (associated with the specified Lagrangian)

Causality and relativistic effects in intranuclear cascade calculations

International Nuclear Information System (INIS)

Kodama, T.; Duarte, S.B.; Chung, K.C.; Donangelo, R.J.; Nazareth, R.A.M.S.

1983-01-01

Relativistic effects in high energy nuclear collisions, when non-invariance of simultaneity is taken into account, are studied. It is shown that the time ordering of nucleon-nucleon collisions is quite different for different observers, giving in some cases non-invariant final results for intranuclear cascade (INC) calculations. In particular, an example of such a case is shown, in which the INC simulation, depending on the reference frame, presents a kind of density instability caused by a specific time ordering of collision events. A new INC calculation, using a causality preserving scheme, which minimizes this kind of relativistic effect is proposed. It is verified that the causality preserving INC prescription essentially recovers the relativistic invariance. (Author) [pt

The relativistic electron wave equation

International Nuclear Information System (INIS)

Dirac, P.A.M.

1977-08-01

The paper was presented at the European Conference on Particle Physics held in Budapest between the 4th and 9th July of 1977. A short review is given on the birth of the relativistic electron wave equation. After Schroedinger has shown the equivalence of his wave mechanics and the matrix mechanics of Heisenberg, a general transformation theory was developed by the author. This theory required a relativistic wave equation linear in delta/delta t. As the Klein--Gordon equation available at this time did not satisfy this condition the development of a new equation became necessary. The equation which was found gave the value of the electron spin and magnetic moment automatically. (D.P.)

Double Relativistic Electron Accelerating Mirror

Directory of Open Access Journals (Sweden)

Saltanat Sadykova

2013-02-01

Full Text Available In the present paper, the possibility of generation of thin dense relativistic electron layers is shown using the analytical and numerical modeling of laser pulse interaction with ultra-thin layers. It was shown that the maximum electron energy can be gained by optimal tuning between the target width, intensity and laser pulse duration. The optimal parameters were obtained from a self-consistent system of Maxwell equations and the equation of motion of electron layer. For thin relativistic electron layers, the gaining of maximum electron energies requires a second additional overdense plasma layer, thus cutting the laser radiation off the plasma screen at the instant of gaining the maximum energy (DREAM-schema.

Relativistic shocks and particle acceleration

International Nuclear Information System (INIS)

Heavens, A.F.

1988-01-01

In this paper, we investigate the fluid dynamics of relativistic shock waves, and use the results to calculate the spectral index of particles accelerated by the Fermi process in such shocks. We have calculated the distributions of Fermi-accelerated particles at shocks propagating into cold proton-electron plasma and also cold electron-positron plasma. We have considered two different power spectra for the scattering waves, and find, in contrast to the non-relativistic case, that the spectral index of the accelerated particles depends on the wave power spectrum. On the assumption of thermal equilibrium both upstream and downstream, we present some useful fits for the compression ratio of shocks propagating at arbitrary speeds into gas of any temperature. (author)

Second quantization of classical nonlinear relativistic field theory. Pt. 2

International Nuclear Information System (INIS)

Balaban, T.

1976-01-01

The construction of a relativistic interacting local quantum field is given in two steps: first the classical nonlinear relativistic field theory is written down in terms of Poisson brackets, with initial conditions as canonical variables: next a representation of Poisson bracket Lie algebra by means of linear operators in the topological vector space is given and an explicit form of a local interacting relativistic quantum field PHI is obtained. (orig./BJ) [de

Fundamental laws of relativistic classical dynamics revisited

International Nuclear Information System (INIS)

Blaquiere, Augustin

1977-01-01

By stating that a linear differential form, whose coefficients are the components of the momentum and the energy of a particle, has an antiderivative, the basic equations of the dynamics of points are obtained, in the relativistic case. From the point of view of optimization theory, a connection between our condition and the Bellman-Isaacs equation of dynamic programming is discussed, with a view to extending the theory to relativistic wave mechanics [fr

Relativistic Binaries in Globular Clusters

Directory of Open Access Journals (Sweden)

Matthew J. Benacquista

2013-03-01

Full Text Available Galactic globular clusters are old, dense star systems typically containing 10^4 – 10^6 stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense population of stars, globular clusters are the scene of many interesting close dynamical interactions between stars. These dynamical interactions can alter the evolution of individual stars and can produce tight binary systems containing one or two compact objects. In this review, we discuss theoretical models of globular cluster evolution and binary evolution, techniques for simulating this evolution that leads to relativistic binaries, and current and possible future observational evidence for this population. Our discussion of globular cluster evolution will focus on the processes that boost the production of tight binary systems and the subsequent interaction of these binaries that can alter the properties of both bodies and can lead to exotic objects. Direct N-body integrations and Fokker–Planck simulations of the evolution of globular clusters that incorporate tidal interactions and lead to predictions of relativistic binary populations are also discussed. We discuss the current observational evidence for cataclysmic variables, millisecond pulsars, and low-mass X-ray binaries as well as possible future detection of relativistic binaries with gravitational radiation.

Ideals and anti-ideals students of the basic and senior school

Directory of Open Access Journals (Sweden)

Vladimir S. Sobkin

2017-09-01

Full Text Available The paper is devoted to the study of representations of the ideals and anti-ideals in secondary and high schools students. The study is important due to connection with the peculiarities of modern adolescent socialization in the context of contemporary social cultural realities. Shaping the world view in students is significantly influenced by the choice of values and the social role model. In this regard, the aim of this study was to examine gender and age dynamics of different groups of personalities related to the politics and spiritual culture in the structure of ideals and anti-idials in modern adolescents. Aggravation of the internal and external political situation, politically-oriented media content and society as a whole, the introduction of information technologies in various spheres of life, the «western» background of cultural values and information environment, the shift of sex-role identification has a significant influence on gender-specific and age-specific dynamics and significance of different groups of personalities in the structure of ideals and anti-idials in modern adolescents are based on the data of content analysis and a questionnaire survey of 2,273 students, grades 5-11. The features of the structure of ideals and anti-idials of boys and girls, which are formed under the influence of gender identification are characterized. The analysis of the students’ groups of ideals and anti-idials is held depending on their belonging to the Russian and foreign cultures. The students’ representations of the ideals and anti-idials are of a mixed structure, dominated by the personalities of the real people in comparison with the images (characters of works of literature, cinema, cartoons. The sphere of political culture and ideology (politicians, historical figures that presents male personalities is significant for boys. For girls, besides politics, the literary field (writers and movie actors is more important, where the

Monte Carlo closure for moment-based transport schemes in general relativistic radiation hydrodynamic simulations

Science.gov (United States)

Foucart, Francois

2018-04-01

General relativistic radiation hydrodynamic simulations are necessary to accurately model a number of astrophysical systems involving black holes and neutron stars. Photon transport plays a crucial role in radiatively dominated accretion discs, while neutrino transport is critical to core-collapse supernovae and to the modelling of electromagnetic transients and nucleosynthesis in neutron star mergers. However, evolving the full Boltzmann equations of radiative transport is extremely expensive. Here, we describe the implementation in the general relativistic SPEC code of a cheaper radiation hydrodynamic method that theoretically converges to a solution of Boltzmann's equation in the limit of infinite numerical resources. The algorithm is based on a grey two-moment scheme, in which we evolve the energy density and momentum density of the radiation. Two-moment schemes require a closure that fills in missing information about the energy spectrum and higher order moments of the radiation. Instead of the approximate analytical closure currently used in core-collapse and merger simulations, we complement the two-moment scheme with a low-accuracy Monte Carlo evolution. The Monte Carlo results can provide any or all of the missing information in the evolution of the moments, as desired by the user. As a first test of our methods, we study a set of idealized problems demonstrating that our algorithm performs significantly better than existing analytical closures. We also discuss the current limitations of our method, in particular open questions regarding the stability of the fully coupled scheme.

The incompressible non-relativistic Navier-Stokes equation from gravity

International Nuclear Information System (INIS)

Bhattacharyya, Sayantani; Minwalla, Shiraz; Wadia, Spenta R.

2009-01-01

We note that the equations of relativistic hydrodynamics reduce to the incompressible Navier-Stokes equations in a particular scaling limit. In this limit boundary metric fluctuations of the underlying relativistic system turn into a forcing function identical to the action of a background electromagnetic field on the effectively charged fluid. We demonstrate that special conformal symmetries of the parent relativistic theory descend to 'accelerated boost' symmetries of the Navier-Stokes equations, uncovering a conformal symmetry structure of these equations. Applying our scaling limit to holographically induced fluid dynamics, we find gravity dual descriptions of an arbitrary solution of the forced non-relativistic incompressible Navier-Stokes equations. In the holographic context we also find a simple forced steady state shear solution to the Navier-Stokes equations, and demonstrate that this solution turns unstable at high enough Reynolds numbers, indicating a possible eventual transition to turbulence.

Relativistic implications of the quantum phase

International Nuclear Information System (INIS)

Low, Stephen G

2012-01-01

The quantum phase leads to projective representations of symmetry groups in quantum mechanics. The projective representations are equivalent to the unitary representations of the central extension of the group. A celebrated example is Wigner's formulation of special relativistic quantum mechanics as the projective representations of the inhomogeneous Lorentz group. However, Wigner's formulation makes no mention of the Weyl-Heisenberg group and the hermitian representation of its algebra that are the Heisenberg commutation relations fundamental to quantum physics. We put aside the relativistic symmetry and show that the maximal quantum symmetry that leaves the Heisenberg commutation relations invariant is the projective representations of the conformally scaled inhomogeneous symplectic group. The Weyl-Heisenberg group and noncommutative structure arises directly because the quantum phase requires projective representations. We then consider the relativistic implications of the quantum phase that lead to the Born line element and the projective representations of an inhomogeneous unitary group that defines a noninertial quantum theory. (Understanding noninertial quantum mechanics is a prelude to understanding quantum gravity.) The remarkable properties of this symmetry and its limits are studied.

First quantized noncritical relativistic Polyakov string

International Nuclear Information System (INIS)

Jaskolski, Z.; Meissner, K.A.

1994-01-01

The first quantization of the relativistic Brink-DiVecchia-Howe-Polyakov (BDHP) string in the range 1 < d 25 is considered. It is shown that using the Polyakov sum over bordered surfaces in the Feynman path integral quantization scheme one gets a consistent quantum mechanics of relativistic 1-dim extended objects in the range 1 < d < 25. In particular, the BDHP string propagator is exactly calculated for arbitrary initial and final string configurations and the Hilbert space of physical states of noncritical BDHP string is explicitly constructed. The resulting theory is equivalent to the Fairlie-Chodos-Thorn massive string model. In contrast to the conventional conformal field theory approach to noncritical string and random surfaces in the Euclidean target space the path integral formulation of the Fairlie-Chodos-Thorn string obtained in this paper does not rely on the principle of conformal invariance. Some consequences of this feature for constructing a consistent relativistic string theory based on the ''splitting-joining'' interaction are discussed. (author). 42 refs, 1 fig

Relativistic stellar dynamics

International Nuclear Information System (INIS)

Contopoulos, G.

1983-01-01

In this paper, three main areas of relativistic stellar dynamics are reviewed: (a) The dynamics of clusters, or nuclei of galaxies, of very high density; (b) The dynamics of systems containing a massive black hole; and (c) The dynamics of particles (and photons) in an expanding Universe. The emphasis is on the use of orbit perturbations. (Auth.)

Fundamental Relativistic Rotator

International Nuclear Information System (INIS)

Staruszkiewicz, A.

2008-01-01

Professor Jan Weyssenhoff was Myron Mathisson's sponsor and collaborator. He introduced a class of objects known in Cracow as '' kreciolki Weyssenhoffa '', '' Weyssenhoff's rotating little beasts ''. The Author describes a particularly simple object from this class. The relativistic rotator described in the paper is such that its both Casimir invariants are parameters rather than constants of motion. (author)

Kubo formulas for relativistic fluids in strong magnetic fields

International Nuclear Information System (INIS)

Huang Xuguang; Sedrakian, Armen; Rischke, Dirk H.

2011-01-01

Magnetohydrodynamics of strongly magnetized relativistic fluids is derived in the ideal and dissipative cases, taking into account the breaking of spatial symmetries by a quantizing magnetic field. A complete set of transport coefficients, consistent with the Curie and Onsager principles, is derived for thermal conduction, as well as shear and bulk viscosities. It is shown that in the most general case the dissipative function contains five shear viscosities, two bulk viscosities, and three thermal conductivity coefficients. We use Zubarev's non-equilibrium statistical operator method to relate these transport coefficients to correlation functions of the equilibrium theory. The desired relations emerge at linear order in the expansion of the non-equilibrium statistical operator with respect to the gradients of relevant statistical parameters (temperature, chemical potential, and velocity.) The transport coefficients are cast in a form that can be conveniently computed using equilibrium (imaginary-time) infrared Green's functions defined with respect to the equilibrium statistical operator. - Highlights: → Strong magnetic fields can make charged fluids behave anisotropically. → Magnetohydrodynamics for these fluids contains 5 shear, 2 bulk viscosities, and 3 heat conductivities. → We derive Kubo formulas for these transport coefficients.

Strong-field relativistic processes in highly charged ions

Energy Technology Data Exchange (ETDEWEB)

Postavaru, Octavian

2010-12-08

In this thesis we investigate strong-field relativistic processes in highly charged ions. In the first part, we study resonance fluorescence of laser-driven highly charged ions in the relativistic regime by solving the time-dependent master equation in a multi-level model. Our ab initio approach based on the Dirac equation allows for investigating highly relativistic ions, and, consequently, provides a sensitive means to test correlated relativistic dynamics, bound-state quantum electrodynamic phenomena and nuclear effects by applying coherent light with x-ray frequencies. Atomic dipole or multipole moments may be determined to unprecedented accuracy by measuring the interference-narrowed fluorescence spectrum. Furthermore, we investigate the level structure of heavy hydrogenlike ions in laser beams. Interaction with the light field leads to dynamic shifts of the electronic energy levels, which is relevant for spectroscopic experiments. We apply a fully relativistic description of the electronic states by means of the Dirac equation. Our formalism goes beyond the dipole approximation and takes into account non-dipole effects of retardation and interaction with the magnetic field components of the laser beam. We predicted cross sections for the inter-shell trielectronic recombination (TR) and quadruelectronic recombination processes which have been experimentally confirmed in electron beam ion trap measurements, mainly for C-like ions, of Ar, Fe and Kr. For Kr{sup 30}+, inter-shell TR contributions of nearly 6% to the total resonant photorecombination rate were found. (orig.)

Increased body satisfaction after exposure to thin ideal children's television in young girls showing thin ideal internalisation.

Science.gov (United States)

Anschutz, Doeschka J; Engels, Rutger C M E; Van Strien, Tatjana

2012-01-01

This study tested the direct effect of watching thin ideal children's television on body satisfaction in preadolescent girls (6-8 years old). A within-subject design was used in which girls (N = 51) were tested three times. They watched television clips in random order containing either (1) thin ideal animated characters or (2) animated characters with no thin ideal features or (3) 'real' human actors with no thin ideal features. After watching, their state body satisfaction was measured. Girls with higher levels of thin ideal internalisation showed higher body satisfaction after exposure to the thin ideal characters than after exposure to animated or real characters featuring no thin ideal features. No differences on body satisfaction between the exposure conditions were found in girls with lower levels of thin ideal internalisation. The results might suggest that young girls who internalised the thin ideal are inspired by thin ideal characters in children's media.

Probing the onset of laser-induced relativistic transparency in massive targets

Science.gov (United States)

Wang, Tao; Wagner, Craig; Toncian, Toma; Dyer, Gilliss; Arefiev, Alexey; Ditmire, Todd

2017-10-01

We have investigated a novel approach of using harmonics of the laser frequency generated in the plasma to detect the onset of relativistic transparency induced by an intense laser pulse. The onset of the transparency is directly associated with a forward motion of a relativistically adjusted critical surface. The corresponding velocity is relativistic, so the harmonics generated at this critical surface are noticeably shifted. Using particle-in-cell simulations, we have confirmed that the resulting shift greatly exceeds the shift produced during a hole-boring process when the relativistic transparency plays no role, which allows us to clearly identify the onset of the relativistic transparency. Experiments that we have carried out at the Texas Petawatt laser showcase this approach. The 3rd harmonic signal detected in experiments with massive targets irradiated at laser intensities around 1020 W/cm2 has a pronounced shift associated with the relativistic transparency. The shift represents a recession of the relativistically adjusted critical surface with a velocity close to 0.2 c. This approach opens a new possibility of detecting changes in the optical properties of matter induced by intense laser pulses even when no transmission of the laser pulse takes place. This research was supported part by NSF (Grant No. 1632777) and NNSA (Cont. No. DE-NA0002008). Simulations were performed using HPC resources at TACC at the University of Texas.

Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma

International Nuclear Information System (INIS)

Patil, S. D.; Takale, M. V.

2013-01-01

In the present paper, we have employed the quantum dielectric response in thermal quantum plasma to model relativistic self-focusing of Gaussian laser beam in a plasma. We have presented an extensive parametric investigation of the dependence of beam-width parameter on distance of propagation in relativistic thermal quantum plasma. We have studied the role of Fermi temperature in the phenomenon of self-focusing. It is found that the quantum effects cause much higher oscillations of beam-width parameter and better relativistic focusing of laser beam in thermal quantum plasma in comparison with that in the relativistic cold quantum plasma and classical relativistic plasma. Our computations show more reliable results in comparison to the previous works

Two centre problems in relativistic atomic physics

Energy Technology Data Exchange (ETDEWEB)

McConnell, Sean R.

2013-01-09

The work contained within this thesis is concerned with the explanation and usage of a set of theoretical procedures for the study of static and dynamic two-centre problems in the relativistic framework of Dirac's equation. Two distinctly different theories for handling time-dependent atomic interactions are reviewed, namely semi-classical perturbation theory and a non-perturbative numerical technique based on the coupled channel equation to directly solve the time-dependent, two-centre Dirac equation. The non-perturbative numerical technique has been developed independently and the calculations performed with it are entirely new. Calculations for ionisation cross sections and state occupancies are conducted for both these methods. The non-perturbative technique for relativistic two-centre problems is extensively explained and, given its novelty, a probity test is conducted between this technique and that of the well established perturbation theory in calculating K-and L-shell ionisation cross sections for the alpha decay of initially Hydrogen-like Polonium. To that end, an in depth outline of the perturbative technique is also made for both collision and decay processes. As well as the comparison test mentioned, this technique is also applied to the analysis of cross sections of the promotion of a single electron into the positive continuum from either a K- or L-shell due to the alpha decay of heavy, neutral nuclei (Gadolinium, Polonium and Thorium). Dirac-Coulomb eigenfunctions centred on the parent nucleus of the decay pair are taken as the basis for use in the cross section calculations utilising first order, semi-classical pertubation theory. The excellent congruence between both techniques justifies the usage of the non-perturbative algorithms in the subsequent analysis of collisions between very heavy, highly charged ions. As such, a set of calculations are performed examining the bound and continuum state occupancy of the electronic levels during a

Relativistic rotation and the anholonomic object

International Nuclear Information System (INIS)

Corum, J.F.

1977-01-01

The purpose of this communication is to call attention to the conceptual economy provided by the object of anholonomity for the theory of relativity. This geometric object expresses certain consequences of relativity theory and provides a single, simple framework for discussing a variety of phenomena. It particularly clarifies the description of relativistic rotation. The relativistic rotational transformation of the four coordinate differentials of flat space--time generates a set of anholonomic, or inexact differentials, whose duals are an orthogonal set of basis vectors. How should a rotating observer interpret physical events referred to such orthogonal, but anholonomic frames The answer to this question rests upon the origin and physical significance of the object of anholonomity. It is demonstrated that not only is the rotational Lorentz transformation an anholonomic transformation, but that the intrinsic anholonomic effects are essential to interpreting rotational phenomena. In particular, the Sagnac effect may be interpreted as the physical manifestation of temporal anholonomity under rotation. The Thomas precession of a reference axis may be interpreted as a consequence of the spatial anholonomity of the rotating frame. Further, the full four-dimensional covariance of Maxwellian electrodynamics, under a relativistic Lorentz rotation, is possible only with the inclusion of anholonomic effects. The anholonomic approach clarifies the distinction between the physically different operations of source rotation and observer rotation in a flat space--time. It is finally concluded that a consistant theory of relativistic rotation, satisfying the principle of general covariance, inherently requires the presence of the object of anholonomity

Relativistic Tsiolkovsky equation -- a case study in special relativity

Science.gov (United States)

Redd, Jeremy; Panin, Alexander

2011-10-01

A possibility of using antimatter in future space propulsion systems is seriously discussed in scientific literature. Annihilation of matter and antimatter is not only the energy source of ultimate density 9x10^16 J/kg (provided that antimatter fuel is available on board or can be collected along the journey) but also potentially allows to reach ultimate exhaust speed -- speed of light c. Using relativistic rocket equation we discuss the feasibility of achieving relativistic velocities with annihilation powered photon engine, as well as the advantages and disadvantages of interstellar travel with relativistic and ultrarelativistic velocities.

Relativistic covariant wave equations and acausality in external fields

International Nuclear Information System (INIS)

Pijlgroms, R.B.J.

1980-01-01

The author considers linear, finite dimensional, first order relativistic wave equations: (βsup(μ)ideltasub(μ)-β)PSI(x) = 0 with βsup(μ) and β constant matrices. Firstly , the question of the relativistic covariance conditions on these equations is considered. Then the theory of these equations with β non-singular is summarized. Theories with βsup(μ), β square matrices and β singular are also discussed. Non-square systems of covariant relativistic wave equations for arbitrary spin > 1 are then considered. Finally, the interaction with external fields and the acausality problem are discussed. (G.T.H.)

Is the relativistic approach really useful to nuclear reactions?

CERN Document Server

Miyazaki, K

2003-01-01

We have reconsidered the non-relativistic distorted-wave t-matrix approximation (NR-DWTA) for proton knockout (p,2p) reaction using modern high-quality phenomenological optical potentials and NN t-matrix. We have calculated 40Ca(p,2p) reactions at T_LAB=200MeV and compared the results with the relativistic distorted-wave impulse approximation (RDWIA) calculations. It is found that the NR-DWTA is superior to the RDWIA in consistent description of the cross section and the analyzing power. An immediate relativistic extension of the DWIA to the nuclear reaction has a problem.

On the Velocity of Moving Relativistic Unstable Quantum Systems

Directory of Open Access Journals (Sweden)

K. Urbanowski

2015-01-01

Full Text Available We study properties of moving relativistic quantum unstable systems. We show that in contrast to the properties of classical particles and quantum stable objects the velocity of freely moving relativistic quantum unstable systems cannot be constant in time. We show that this new quantum effect results from the fundamental principles of the quantum theory and physics: it is a consequence of the principle of conservation of energy and of the fact that the mass of the quantum unstable system is not defined. This effect can affect the form of the decay law of moving relativistic quantum unstable systems.

Relativistic effects on large amplitude nonlinear Langmuir waves in a two-fluid plasma

International Nuclear Information System (INIS)

Nejoh, Yasunori

1994-07-01

Large amplitude relativistic nonlinear Langmuir waves are analyzed by the pseudo-potential method. The existence conditions for nonlinear Langmuir waves are confirmed by considering relativistic high-speed electrons in a two-fluid plasma. The significant feature of this investigation is that the propagation of nonlinear Langmuir waves depends on the ratio of the electron streaming velocity to the velocity of light, the normalized potential and the ion mass to electron mass ratio. The constant energy is determined by the specific range of the relativistic effect. In the non-relativistic limit, large amplitude relativistic Langmuir waves do not exist. The present investigation predicts new findings of large amplitude nonlinear Langmuir waves in space plasma phenomena in which relativistic electrons are important. (author)

Relativistic charged fluids: hydrodynamic and kinetic approaches

International Nuclear Information System (INIS)

Debbasch, F.; Bonnaud, G.

1991-10-01

This report gives a rigorous and consistent hydrodynamic and kinetic description of a charged fluid and the basis equations, in a relativistic context. This study should lead to a reliable model, as much analytical as numerical, of relativistic plasmas which will appear in the interaction of a strong laser field with a plasma. For simplicity, we limited our study to a perfect fluid or, in other words, we disregarded the energy dissipation processes inside the fluid [fr

Summary of the relativistic heavy ion sessions

International Nuclear Information System (INIS)

Harris, J.W.

1988-01-01

The topics covered in the Relativistic Heavy Ion Sessions span four orders of magnitude in energy in the laboratory and a few more in theory. In the two years since the last Intersections conference, experiments in the field of very high energy heavy ion research have begun at CERN and Brookhaven. The prime motivation for these experiments is the possibility of forming quark matter. This paper is a review of the topics covered in the Relativistic Heavy Ion Sessions

Relativistic treatment of fermion-antifermion bound states

International Nuclear Information System (INIS)

Lucha, W.; Rupprecht, H.; Schoeberl, F.F.

1990-01-01

We discuss the relativistic treatment of fermion-antifermion bound states by an effective-Hamiltonian method which imitates their description in terms of nonrelativistic potential models: the effective interaction potential, to be used in a Schroedinger equation which incorporates relativistic kinematics, is derived from the underlying quantum field theory. This approach is equivalent to the instantaneous approximation to the Bethe-Salpeter equation called Salpeter equation but comes closer to physical intuition than the latter one. (Author) 14 refs

Exact quantisation of the relativistic Hopfield model

Energy Technology Data Exchange (ETDEWEB)

Belgiorno, F., E-mail: francesco.belgiorno@polimi.it [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo 32, IT-20133 Milano (Italy); INdAM-GNFM (Italy); Cacciatori, S.L., E-mail: sergio.cacciatori@uninsubria.it [Department of Science and High Technology, Università dell’Insubria, Via Valleggio 11, IT-22100 Como (Italy); INFN sezione di Milano, via Celoria 16, IT-20133 Milano (Italy); Dalla Piazza, F., E-mail: f.dallapiazza@gmail.com [Università “La Sapienza”, Dipartimento di Matematica, Piazzale A. Moro 2, I-00185, Roma (Italy); Doronzo, M., E-mail: m.doronzo@uninsubria.it [Department of Science and High Technology, Università dell’Insubria, Via Valleggio 11, IT-22100 Como (Italy)

2016-11-15

We investigate the quantisation in the Heisenberg representation of a relativistically covariant version of the Hopfield model for dielectric media, which entails the interaction of the quantum electromagnetic field with the matter dipole fields, represented by a mesoscopic polarisation field. A full quantisation of the model is provided in a covariant gauge, with the aim of maintaining explicit relativistic covariance. Breaking of the Lorentz invariance due to the intrinsic presence in the model of a preferred reference frame is also taken into account. Relativistic covariance forces us to deal with the unphysical (scalar and longitudinal) components of the fields, furthermore it introduces, in a more tricky form, the well-known dipole ghost of standard QED in a covariant gauge. In order to correctly dispose of this contribution, we implement a generalised Lautrup trick. Furthermore, causality and the relation of the model with the Wightman axioms are also discussed.

Fermi liquid description of relativistic high density matter

Science.gov (United States)

Pal, K.; Dutt-Mazumder, A. K.

2011-06-01

We calculate pionic contribution to the relativistic Fermi Liquid parameters (RFLPs) using Chiral Effective Lagrangian. The RFLPs so determined are then used to calculate chemical potential, exchange energy due to πN interaction. We also compare the results of exchange energy from two loop ring diagrams involving σ, ω and π meson with what one obtains from the relativistic Fermi Liquid theory (RFLT).

Relativistic motion in gamma-ray bursts

International Nuclear Information System (INIS)

Krolik, J.H.; Pier, E.A.

1991-01-01

Three fundamental problems affect models of gamma-ray bursts, i.e., the energy source, the ability of high-energy photons to escape the radiation region, and the comparative weakness of X-ray emission. It is indicated that relativistic bulk motion of the gamma-ray-emitting plasma generically provides a solution to all three of these problems. Results show that, if the plasma that produces gamma-ray bursts has a bulk relativistic velocity with Lorentz factor gamma of about 10, several of the most troubling problems having to do with gamma-ray bursts are solved. 42 refs

Path integral for relativistic particle theory

International Nuclear Information System (INIS)

Fradkin, E.S.; Gitman, D.M.; Shvartsman, Sh.M.

1990-06-01

An action for a relativistic spinning particle interacting with external electromagnetic field is considered in reparametrization and local supergauge invariant form. It is shown that various path integral representations derived for the causal Green function correspond to the different forms of the relativistic particle action. The analogy of the path integral derived with the Lagrangian path integral of the field theory is discussed. It is shown that to obtain the causal propagator, the integration over the null mode of the Lagrangian multiplier corresponding to the reparametrization invariance, has to be performed in the (0,+infinity) limits. (author). 23 refs

Thermodynamic equilibrium in relativistic rotating systems

International Nuclear Information System (INIS)

Suen, W.M.; Washington Univ., St. Louis, MO; Young, K.

1988-01-01

The thermodynamic equilibrium configurations of relativistic rotating stars are studied using the maximum entropy principle. It is shown that the heuristic arguments for the equilibrium conditions can be developed into a maximum entropy principle in which the variations are carried out in a fixed background spacetime. This maximum principle with the fixed background assumption is technically simpler than, but has to be justified by, a maximum entropy principle without the assumption. Such a maximum entropy principle is formulated in this paper, showing that the general relativistic system can be treated on the same footing as other long-range force systems. (author)

Heavy-ion interactions in relativistic mean-field models

International Nuclear Information System (INIS)

Rashdan, M.

1996-01-01

The interaction potential between spherical nuclei and the elastic scattering cross section are calculated within relativistic mean-field (linear and non-linear) models, using a generalized relativistic local density approximation. The nuclear densities are calculated self-consistently from the solution of the relativistic mean-field equations. It is found that both the linear and non-linear models predict the characteristic switching-over phenomenon of the heavy-ion nuclear potential, where the potential gets attraction with increasing energy up to some value where it reverses this behaviour. The non-linear NLC model predicts a deeper potential than the linear LW model. The elastic scattering cross section calculated within the non-linear NLC model is in better agreement with experiments than that calculated within the linear LW model. (orig.)

Generalized dilatation operator method for non-relativistic holography

Energy Technology Data Exchange (ETDEWEB)

Chemissany, Wissam, E-mail: wissam@stanford.edu [Department of Physics and SITP, Stanford University, Stanford, CA 94305 (United States); Papadimitriou, Ioannis, E-mail: ioannis.papadimitriou@csic.es [Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid, Madrid 28049 (Spain)

2014-10-07

We present a general algorithm for constructing the holographic dictionary for Lifshitz and hyperscaling violating Lifshitz backgrounds for any value of the dynamical exponent z and any value of the hyperscaling violation parameter θ compatible with the null energy condition. The objective of the algorithm is the construction of the general asymptotic solution of the radial Hamilton–Jacobi equation subject to the desired boundary conditions, from which the full dictionary can be subsequently derived. Contrary to the relativistic case, we find that a fully covariant construction of the asymptotic solution for running non-relativistic theories necessitates an expansion in the eigenfunctions of two commuting operators instead of one. This provides a covariant but non-relativistic grading of the expansion, according to the number of time derivatives.

Beware of ideals in education

NARCIS (Netherlands)

Heyting, G.F.

2004-01-01

In reaction to Doret De Ruyter's recent defence of the importance of ideals in education, I advocate cautiousness in three respects. First, I explain the importance of distinguishing ideals more sharply from goals by demonstrating the problems of considering ideals even approximately realisable.

Relativistic effects in elastic scattering of electrons in TEM

International Nuclear Information System (INIS)

Rother, Axel; Scheerschmidt, Kurt

2009-01-01

Transmission electron microscopy typically works with highly accelerated thus relativistic electrons. Consequently the scattering process is described within a relativistic formalism. In the following, we will examine three different relativistic formalisms for elastic electron scattering: Dirac, Klein-Gordon and approximated Klein-Gordon, the standard approach. This corresponds to a different consideration of spin effects and a different coupling to electromagnetic potentials. A detailed comparison is conducted by means of explicit numerical calculations. For this purpose two different formalisms have been applied to the approaches above: a numerical integration with predefined boundary conditions and the multislice algorithm, a standard procedure for such simulations. The results show a negligibly small difference between the different relativistic equations in the vicinity of electromagnetic potentials, prevailing in the electron microscope. The differences between the two numeric approaches are found to be small for small-angle scattering but eventually grow large for large-angle scattering, recorded for instance in high-angle annular dark field.

Physical stress, mass, and energy for non-relativistic matter

Science.gov (United States)

Geracie, Michael; Prabhu, Kartik; Roberts, Matthew M.

2017-06-01

For theories of relativistic matter fields there exist two possible definitions of the stress-energy tensor, one defined by a variation of the action with the coframes at fixed connection, and the other at fixed torsion. These two stress-energy tensors do not necessarily coincide and it is the latter that corresponds to the Cauchy stress measured in the lab. In this note we discuss the corresponding issue for non-relativistic matter theories. We point out that while the physical non-relativistic stress, momentum, and mass currents are defined by a variation of the action at fixed torsion, the energy current does not admit such a description and is naturally defined at fixed connection. Any attempt to define an energy current at fixed torsion results in an ambiguity which cannot be resolved from the background spacetime data or conservation laws. We also provide computations of these quantities for some simple non-relativistic actions.

Relativistic Many-Body Theory A New Field-Theoretical Approach

CERN Document Server

Lindgren, Ingvar

2011-01-01

Relativistic Many-Body Theory treats — for the first time — the combination of relativistic atomic many-body theory with quantum-electrodynamics (QED) in a unified manner. This book can be regarded as a continuation of the book by Lindgren and Morrison, Atomic Many-Body Theory (Springer 1986), which deals with the non-relativistic theory of many-electron systems, describing several means of treating the electron correlation to essentially all orders of perturbation theory. The treatment of the present book is based upon quantum-field theory, and demonstrates that when the procedure is carried to all orders of perturbation theory, two-particle systems are fully compatible with the relativistically covariant Bethe-Salpeter equation. This procedure can be applied to arbitrary open-shell systems, in analogy with the standard many-body theory, and it is also applicable to systems with more than two particles. Presently existing theoretical procedures for treating atomic systems are, in several cases, insuffici...

Relativistic quantum mechanics of bosons

International Nuclear Information System (INIS)

Ghose, P.; Home, D.; Sinha Roy, M.N.

1993-01-01

We show that it is possible to use the Klein-Gordon, Proca and Maxwell formulations to construct multi-component relativistic configuration space wavefunctions of spin-0 and spin-1 bosons in an external field. These wavefunctions satisfy the first-order Kemmer-Duffin equation. The crucial ingredient is the use of the future-causal normal n μ (n μ n μ =1, n 0 >0) to the space-like hypersurfaces foliating space-time, inherent in the concept of a relativistic wavefunction, to construct a conserved future-causal probability current four-vector from the second-rank energy-momentum tensor, following Holland's prescription. The existence of a Hermitian position operator, localized solutions, compatibility with the second quantized theories and the question of interpretation are discussed. (orig.)

Effect of the strange axial form factor on structure functions for neutral current neutrino scattering in the quasielastic region

International Nuclear Information System (INIS)

Kim, Kyungsik

2011-01-01

We study the effect of the strange axial form factor on various structure functions for the neutral reaction of neutrino-nucleus scattering in the quasielastic region within the framework of a relativistic single particle model. We use 12 C as the target nucleus, and the incident neutrino energy range is between 150 MeV and 1.5 GeV. The structure functions are extracted at a fixed three momentum transfer and energy transfer by using the intrinsic helicity of neutrino. While the effect of the strange axial form factor is very small, the effect on various structure functions is exhibited explicitly.

On the relativistic and nonrelativistic electron descriptions in high-energy atomic collisions

International Nuclear Information System (INIS)

Voitkiv, A.B

2007-01-01

We consider the relativistic and nonrelativistic descriptions of an atomic electron in collisions with point-like charged projectiles moving at relativistic velocities. We discuss three different forms of the fully relativistic first-order transition amplitude. Using the Schroedinger-Pauli equation to describe the atomic electron we establish the correct form of the nonrelativistic first-order transition amplitude. We also show that the so-called semi-relativistic treatment, in which the Darwin states are used to describe the atomic electron, is in fact fully equivalent to the nonrelativistic consideration. The comparison of results obtained with the relativistic and nonrelativistic electron descriptions shows that the latter is accurate within 20-30% up to Z a ∼ a is the atomic nuclear charge

Quasi-linear equation for magnetoplasma oscillations in the weakly relativistic approximation

International Nuclear Information System (INIS)

Rizzato, F.B.

1985-01-01

Some limitations which are present in the dynamical equations for collisionless plasmas are discussed. Some elementary corrections to the linear theories are obtained in a heuristic form, which directly lead to the so-called quasi-linear theories in its non-relativistic and relativistic forms. The effect of the relativistic variation of the gyrofrequency on the diffusion coefficient is examined in a typically perturbative approximation. (author)

The media's representation of the ideal male body: a cause for muscle dysmorphia?

Science.gov (United States)

Leit, Richard A; Gray, James J; Pope, Harrison G

2002-04-01

This study sought to examine the effects of media images on men's attitudes toward their body appearance. A group of college men viewed advertisements showing muscular men, whereas a control group viewed neutral advertisements. Immediately thereafter, participants performed a computerized test of body image perception while unaware of the hypotheses being tested in the study. The students exposed to the muscular images showed a significantly greater discrepancy between their own perceived muscularity and the level of muscularity that they ideally wanted to have. These findings suggest that media images, even in a brief presentation, can affect men's views of their bodies. Copyright 2002 by Wiley Periodicals, Inc.

Four-Component Relativistic Density-Functional Theory Calculations of Nuclear Spin-Rotation Constants: Relativistic Effects in p-Block Hydrides.

Science.gov (United States)

Komorovsky, Stanislav; Repisky, Michal; Malkin, Elena; Demissie, Taye B; Ruud, Kenneth

2015-08-11

We present an implementation of the nuclear spin-rotation (SR) constants based on the relativistic four-component Dirac-Coulomb Hamiltonian. This formalism has been implemented in the framework of the Hartree-Fock and Kohn-Sham theory, allowing assessment of both pure and hybrid exchange-correlation functionals. In the density-functional theory (DFT) implementation of the response equations, a noncollinear generalized gradient approximation (GGA) has been used. The present approach enforces a restricted kinetic balance condition for the small-component basis at the integral level, leading to very efficient calculations of the property. We apply the methodology to study relativistic effects on the spin-rotation constants by performing calculations on XHn (n = 1-4) for all elements X in the p-block of the periodic table and comparing the effects of relativity on the nuclear SR tensors to that observed for the nuclear magnetic shielding tensors. Correlation effects as described by the density-functional theory are shown to be significant for the spin-rotation constants, whereas the differences between the use of GGA and hybrid density functionals are much smaller. Our calculated relativistic spin-rotation constants at the DFT level of theory are only in fair agreement with available experimental data. It is shown that the scaling of the relativistic effects for the spin-rotation constants (varying between Z(3.8) and Z(4.5)) is as strong as for the chemical shieldings but with a much smaller prefactor.

Scaling for deuteron structure functions in a relativistic light-front model

International Nuclear Information System (INIS)

Polyzou, W.N.; Gloeckle, W.

1996-01-01

Scaling limits of the structure functions [B.D. Keister, Phys. Rev. C 37, 1765 (1988)], W 1 and W 2 , are studied in a relativistic model of the two-nucleon system. The relativistic model is defined by a unitary representation, U(Λ,a), of the Poincaracute e group which acts on the Hilbert space of two spinless nucleons. The representation is in Dirac close-quote s [P.A.M. Dirac, Rev. Mod. Phys. 21, 392 (1949)] light-front formulation of relativistic quantum mechanics and is designed to give the experimental deuteron mass and n-p scattering length. A model hadronic current operator that is conserved and covariant with respect to this representation is used to define the structure tensor. This work is the first step in a relativistic extension of the results of Hueber, Gloeckle, and Boemelburg. The nonrelativistic limit of the model is shown to be consistent with the nonrelativistic model of Hueber, Gloeckle, and Boemelburg. [D. Hueber et al. Phys. Rev. C 42, 2342 (1990)]. The relativistic and nonrelativistic scaling limits, for both Bjorken and y scaling are compared. The interpretation of y scaling in the relativistic model is studied critically. The standard interpretation of y scaling requires a soft wave function which is not realized in this model. The scaling limits in both the relativistic and nonrelativistic case are related to probability distributions associated with the target deuteron. copyright 1996 The American Physical Society

Electromagnetic solitons in degenerate relativistic electron–positron plasma

International Nuclear Information System (INIS)

Berezhiani, V I; Shatashvili, N L; Tsintsadze, N L

2015-01-01

The existence of soliton-like electromagnetic (EM) distributions in a fully degenerate electron–positron plasma is studied applying relativistic hydrodynamic and Maxwell equations. For a circularly polarized wave it is found that the soliton solutions exist both in relativistic as well as nonrelativistic degenerate plasmas. Plasma density in the region of soliton pulse localization is reduced considerably. The possibility of plasma cavitation is also shown. (invited comment)

Calculation of relativistic model stars using Regge calculus

International Nuclear Information System (INIS)

Porter, J.

1987-01-01

A new approach to the Regge calculus, developed in a previous paper, is used in conjunction with the velocity potential version of relativistic fluid dynamics due to Schutz [1970, Phys. Rev., D, 2, 2762] to calculate relativistic model stars. The results are compared with those obtained when the Tolman-Oppenheimer-Volkov equations are solved by other numerical methods. The agreement is found to be excellent. (author)

Fermi liquid description of relativistic high density matter

International Nuclear Information System (INIS)

Pal, K.; Dutt-Mazumder, A.K.

2011-01-01

We calculate pionic contribution to the relativistic Fermi Liquid parameters (RFLPs) using Chiral Effective Lagrangian. The RFLPs so determined are then used to calculate chemical potential, exchange energy due to πN interaction. We also compare the results of exchange energy from two loop ring diagrams involving σ, ω and π meson with what one obtains from the relativistic Fermi Liquid theory (RFLT). (author)

Conductivity of a relativistic plasma

Energy Technology Data Exchange (ETDEWEB)

Braams, B.J.; Karney, C.F.F.

1989-03-01

The collision operator for a relativistic plasma is reformulated in terms of an expansion in spherical harmonics. This formulation is used to calculate the electrical conductivity. 13 refs., 1 fig., 1 tab.

Conductivity of a relativistic plasma

International Nuclear Information System (INIS)

Braams, B.J.; Karney, C.F.F.

1989-03-01

The collision operator for a relativistic plasma is reformulated in terms of an expansion in spherical harmonics. This formulation is used to calculate the electrical conductivity. 13 refs., 1 fig., 1 tab

Heavy-to-light form factors for non-relativistic bound states

International Nuclear Information System (INIS)

Bell, G.; Feldmann, Th.

2007-01-01

We investigate transition form factors between non-relativistic QCD bound states at large recoil energy. Assuming the decaying quark to be much heavier than its decay product, the relativistic dynamics can be treated according to the factorization formula for heavy-to-light form factors obtained from the heavy-quark expansion in QCD. The non-relativistic expansion determines the bound-state wave functions to be Coulomb-like. As a consequence, one can explicitly calculate the so-called 'soft-overlap' contribution to the transition form factor

Experimental Observation of a Current-Driven Instability in a Neutral Electron-Positron Beam

Science.gov (United States)

Warwick, J.; Dzelzainis, T.; Dieckmann, M. E.; Schumaker, W.; Doria, D.; Romagnani, L.; Poder, K.; Cole, J. M.; Alejo, A.; Yeung, M.; Krushelnick, K.; Mangles, S. P. D.; Najmudin, Z.; Reville, B.; Samarin, G. M.; Symes, D. D.; Thomas, A. G. R.; Borghesi, M.; Sarri, G.

2017-11-01

We report on the first experimental observation of a current-driven instability developing in a quasineutral matter-antimatter beam. Strong magnetic fields (≥1 T ) are measured, via means of a proton radiography technique, after the propagation of a neutral electron-positron beam through a background electron-ion plasma. The experimentally determined equipartition parameter of ɛB≈10-3 is typical of values inferred from models of astrophysical gamma-ray bursts, in which the relativistic flows are also expected to be pair dominated. The data, supported by particle-in-cell simulations and simple analytical estimates, indicate that these magnetic fields persist in the background plasma for thousands of inverse plasma frequencies. The existence of such long-lived magnetic fields can be related to analog astrophysical systems, such as those prevalent in lepton-dominated jets.

Relativistic treatment of mesonic contributions to quasielastic (e,e')

International Nuclear Information System (INIS)

Blunden, P.G.; Butler, M.N.

1988-03-01

Meson exchange currents play an important role in the description of observables in electron scattering. The authors use a relativistic model with pseudovector pion coupling to study the exchange current contributions, with emphasis on quasielastic kinematics. Starting with the Lagrangian for nucleons interacting with a scalar and vector mason along with pseudovector coupling to pions, they derive the one and two-body electromagnetic currents. They then calculate the longitudinal and transverse pieces of the quasielastic cross section for various nuclei and kinematics. The effects of meson exchange currents are found to be much more important in a relativistic model than in a non-relativistic one

Quadratic algebra approach to relativistic quantum Smorodinsky-Winternitz systems

International Nuclear Information System (INIS)

Marquette, Ian

2011-01-01

There exists a relation between the Klein-Gordon and the Dirac equations with scalar and vector potentials of equal magnitude and the Schroedinger equation. We obtain the relativistic energy spectrum for the four relativistic quantum Smorodinsky-Winternitz systems from their quasi-Hamiltonian and the quadratic algebras studied by Daskaloyannis in the nonrelativistic context. We also apply the quadratic algebra approach directly to the initial Dirac equation for these four systems and show that the quadratic algebras obtained are the same than those obtained from the quasi-Hamiltonians. We point out how results obtained in context of quantum superintegrable systems and their polynomial algebras can be applied to the quantum relativistic case.

Relativistic dynamics, Green function and pseudodifferential operators

Energy Technology Data Exchange (ETDEWEB)

Cirilo-Lombardo, Diego Julio [National Institute of Plasma Physics (INFIP), Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires 1428 (Argentina); Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

2016-06-15

The central role played by pseudodifferential operators in relativistic dynamics is known very well. In this work, operators like the Schrodinger one (e.g., square root) are treated from the point of view of the non-local pseudodifferential Green functions. Starting from the explicit construction of the Green (semigroup) theoretical kernel, a theorem linking the integrability conditions and their dependence on the spacetime dimensions is given. Relativistic wave equations with arbitrary spin and the causality problem are discussed with the algebraic interpretation of the radical operator and their relation with coherent and squeezed states. Also we perform by means of pure theoretical procedures (based in physical concepts and symmetry) the relativistic position operator which satisfies the conditions of integrability: it is a non-local, Lorentz invariant and does not have the same problems as the “local”position operator proposed by Newton and Wigner. Physical examples, as zitterbewegung and rogue waves, are presented and deeply analyzed in this theoretical framework.

Theory of relativistic radiation reflection from plasmas

Science.gov (United States)

Gonoskov, Arkady

2018-01-01

We consider the reflection of relativistically strong radiation from plasma and identify the physical origin of the electrons' tendency to form a thin sheet, which maintains its localisation throughout its motion. Thereby, we justify the principle of relativistic electronic spring (RES) proposed in [Gonoskov et al., Phys. Rev. E 84, 046403 (2011)]. Using the RES principle, we derive a closed set of differential equations that describe the reflection of radiation with arbitrary variation of polarization and intensity from plasma with an arbitrary density profile for an arbitrary angle of incidence. We confirm with ab initio PIC simulations that the developed theory accurately describes laser-plasma interactions in the regime where the reflection of relativistically strong radiation is accompanied by significant, repeated relocation of plasma electrons. In particular, the theory can be applied for the studies of plasma heating and coherent and incoherent emissions in the RES regime of high-intensity laser-plasma interaction.

Nonlinear relativistic plasma resonance: Renormalization group approach

Energy Technology Data Exchange (ETDEWEB)

Metelskii, I. I., E-mail: metelski@lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Kovalev, V. F., E-mail: vfkvvfkv@gmail.com [Dukhov All-Russian Research Institute of Automatics (Russian Federation); Bychenkov, V. Yu., E-mail: bychenk@lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

2017-02-15

An analytical solution to the nonlinear set of equations describing the electron dynamics and electric field structure in the vicinity of the critical density in a nonuniform plasma is constructed using the renormalization group approach with allowance for relativistic effects of electron motion. It is demonstrated that the obtained solution describes two regimes of plasma oscillations in the vicinity of the plasma resonance— stationary and nonstationary. For the stationary regime, the spatiotemporal and spectral characteristics of the resonantly enhanced electric field are investigated in detail and the effect of the relativistic nonlinearity on the spatial localization of the energy of the plasma relativistic field is considered. The applicability limits of the obtained solution, which are determined by the conditions of plasma wave breaking in the vicinity of the resonance, are established and analyzed in detail for typical laser and plasma parameters. The applicability limits of the earlier developed nonrelativistic theories are refined.

Relativistic calculations of one-photon bound-free transition amplitudes in hydrogenic atoms

International Nuclear Information System (INIS)

Simo, E.; Kwato Njock, M.G.

2005-04-01

Photoionization transition matrix of hydrogenic systems are investigated theoretically within the framework of the tensorial formalism with relativistic arguments. Calculations are carried out exactly, without approximation. We derive continuum second-order Dirac-Coulomb Sturmian functions. The numerical simulation of our results is performed in the dipole approximation. We test our theory on selected nucleus from the Periodic Table. The results of the fully relativistic calculations are compared with those of the quasi-relativistic calculations. A conclusion is drawn about the level of reliability of the quite simplified quasi-relativistic approach. (author)

The relativistic invariant and the Galilean mass of bodies

International Nuclear Information System (INIS)

Kapuscik, E.

1992-02-01

We generalize the concept of the Galilean mass to the relativistic case. In the case of inequality of Galilean and inertial masses we calculate the relativistic invariant being constant along the trajectory of the moving body. It enables us to define an invariant measure of inertia of bodies. 4 refs. (author)

Relativistic Hartree-Bogoliubov description of thorium and uranium isotopes

International Nuclear Information System (INIS)

Naz, Tabassum; Ahmad, Shakeb

2016-01-01

The relativistic Hartree-Bogoliubov (RHB) theory is a relativistic extension of the Hartree-Fock- Bogoliubov theory. It is a unified description of mean-field and pairing correlations and successfully describe the various phenomenon of nuclear structure. In the present work, RHB is applied to study the thorium and uranium isotopes

Atomic structure calculations using the relativistic random phase approximation

International Nuclear Information System (INIS)

Cheng, K.T.; Johnson, W.R.

1981-01-01

A brief review is given for the relativistic random phase approximation (RRPA) applied to atomic transition problems. Selected examples of RRPA calculations on discrete excitations and photoionization are given to illustrate the need of relativistic many-body theories in dealing with atomic processes where both relativity and correlation are important

Relativistic actions for bound-states and applications in the meson spectroscopy

International Nuclear Information System (INIS)

Silva Carvalho, Hendly da.

1991-08-01

We study relativistic equations for bound states of two-body systems using Dirac's constraint formalism and supersymmetry. The two-body system can be of spinless particles, one of them spinning and the other one spinless, or both of them spinning. The interaction is described by scalar, timelike four-vector and spacelike four-vector potentials under Lorentz transformations. As an application we use the relativistic wave equation for two scalar particles and calculate the mass spectra of the mesons treating them as spinless quark-antiquark bound states. The interaction potential in this case is a convenient adaptation of the potential employed in non-relativistic calculations. Finally, we compare our results with more recent experimental data and with theoretical results obtained with the same potential used by us but with a non-relativistic wave equation. We also compare our results with results obtained with the relativistic wave equation but with a different interaction potential. (author). 38 refs, 9 figs, 8 tabs

Decomposition of fuzzy continuity and fuzzy ideal continuity via fuzzy idealization

International Nuclear Information System (INIS)

Zahran, A.M.; Abbas, S.E.; Abd El-baki, S.A.; Saber, Y.M.

2009-01-01

Recently, El-Naschie has shown that the notion of fuzzy topology may be relevant to quantum paretical physics in connection with string theory and E-infinity space time theory. In this paper, we study the concepts of r-fuzzy semi-I-open, r-fuzzy pre-I-open, r-fuzzy α-I-open and r-fuzzy β-I-open sets, which is properly placed between r-fuzzy openness and r-fuzzy α-I-openness (r-fuzzy pre-I-openness) sets regardless the fuzzy ideal topological space in Sostak sense. Moreover, we give a decomposition of fuzzy continuity, fuzzy ideal continuity and fuzzy ideal α-continuity, and obtain several characterization and some properties of these functions. Also, we investigate their relationship with other types of function.

Nonlinear two-stream interaction between a cold, relativistic electron beam and a collisional plasma-Astron experiment

International Nuclear Information System (INIS)

Newberger, B.S.; Thode, L.E.

1979-05-01

Experiments on the two-stream instability of a relativistic electron beam propagating through a neutral gas, carried out with the Lawrence Livermore Laboratory Astron beam, have been analyzed using a nonlinear saturation model for a cold beam. The behavior of the observed microwave emission due to the instability is in good agreement with that of the beam energy loss. Collisions on the plasma electrons weaken the nonlinear state of the instability but do not stabilize the mode. The beam essentially acts as if it were cold, a result substantiated by linear theory for waves propagating along the beam. In order to predict the effect of both beam momentum scatter and plasma electron collisions on the stability of the mode in future experiments a full two-dimensional linear theory must be developed

Non-relativistic conformal symmetries and Newton-Cartan structures

International Nuclear Information System (INIS)

Duval, C; Horvathy, P A

2009-01-01

This paper provides us with a unifying classification of the conformal infinitesimal symmetries of non-relativistic Newton-Cartan spacetime. The Lie algebras of non-relativistic conformal transformations are introduced via the Galilei structure. They form a family of infinite-dimensional Lie algebras labeled by a rational 'dynamical exponent', z. The Schroedinger-Virasoro algebra of Henkel et al corresponds to z = 2. Viewed as projective Newton-Cartan symmetries, they yield, for timelike geodesics, the usual Schroedinger Lie algebra, for which z = 2. For lightlike geodesics, they yield, in turn, the Conformal Galilean Algebra (CGA) of Lukierski, Stichel and Zakrzewski (alias 'alt' of Henkel), with z = 1. Physical systems realizing these symmetries include, e.g. classical systems of massive and massless non-relativistic particles, and also hydrodynamics, as well as Galilean electromagnetism.

New General Relativistic Contribution to Mercury's Perihelion Advance

Science.gov (United States)

Will, Clifford M.

2018-05-01

We point out the existence of a new general relativistic contribution to the perihelion advance of Mercury that, while smaller than the contributions arising from the solar quadrupole moment and angular momentum, is 100 times larger than the second-post-Newtonian contribution. It arises in part from relativistic "crossterms" in the post-Newtonian equations of motion between Mercury's interaction with the Sun and with the other planets, and in part from an interaction between Mercury's motion and the gravitomagnetic field of the moving planets. At a few parts in 1 06 of the leading general relativistic precession of 42.98 arcseconds per century, these effects are likely to be detectable by the BepiColombo mission to place and track two orbiters around Mercury, scheduled for launch around 2018.

New General Relativistic Contribution to Mercury's Perihelion Advance.

Science.gov (United States)

Will, Clifford M

2018-05-11

We point out the existence of a new general relativistic contribution to the perihelion advance of Mercury that, while smaller than the contributions arising from the solar quadrupole moment and angular momentum, is 100 times larger than the second-post-Newtonian contribution. It arises in part from relativistic "crossterms" in the post-Newtonian equations of motion between Mercury's interaction with the Sun and with the other planets, and in part from an interaction between Mercury's motion and the gravitomagnetic field of the moving planets. At a few parts in 10^{6} of the leading general relativistic precession of 42.98 arcseconds per century, these effects are likely to be detectable by the BepiColombo mission to place and track two orbiters around Mercury, scheduled for launch around 2018.

Relativistic mechanics of two interacting particles and bilocal theory

International Nuclear Information System (INIS)

Takabayasi, Takehiko

1975-01-01

New relativistic mechanics of two-particle system is set forth, where the two constituent particles are interacting by an arbitrary (central) action-at-a-distance. The fundamental equations are presented in a form covariant under general transformation of parameters parametrizing the world lines of constituent particles. The theory represents the proper relativistic generalization of the usual Newtonian mechanics in the sense that it tends in the non-relativistic (and weak interaction) limit to the usual mechanics of two particles moving under a corresponding non-relativistic potential. For the analysis of theory it is convenient to choose a certain particular gauge (i.e., parametrization) fixed by two gauge relations. This brings the theory to a canonical formalism accompanied by two weak equations, and in this gauge quantization can be performed. The result verifies that the relativistic quantum mechanics for two particles interacting by an action-at-a-distance is just represented by a bilocal wave equation and a subsidiary condition, with the clarification of its correspondence-theoretical foundation and internal dynamics. As an example the case of Hooke-type force is illustrated, where the internal motions are elliptic oscillations in the center-of-mass frame. Its quantum theory just reproduces the original form of bilocal theory giving bound states lying on a straightly rising trajectory and on its daughter trajectories. (auth.)

Speeds of Propagation in Classical and Relativistic Extended Thermodynamics

Directory of Open Access Journals (Sweden)

Müller Ingo

1999-01-01

Full Text Available The Navier-Stokes-Fourier theory of viscous, heat-conducting fluids provides parabolic equations and thus predicts infinite pulse speeds. Naturally this feature has disqualified the theory for relativistic thermodynamics which must insist on finite speeds and, moreover, on speeds smaller than $c$. The attempts at a remedy have proved heuristically important for a new systematic type of thermodynamics: Extended thermodynamics. That new theory has symmetric hyperbolic field equations and thus it provides finite pulse speeds. Extended thermodynamics is a whole hierarchy of theories with an increasing number of fields when gradients and rates of thermodynamic processes become steeper and faster. The first stage in this hierarchy is the 14-field theory which may already be a useful tool for the relativist in many applications. The 14 fields -- and further fields -- are conveniently chosen from the moments of the kinetic theory of gases. The hierarchy is complete only when the number of fields tends to infinity. In that case the pulse speed of non-relativistic extended thermodynamics tends to infinity while the pulse speed of relativistic extended thermodynamics tends to $c$, the speed of light. In extended thermodynamics symmetric hyperbolicity -- and finite speeds -- are implied by the concavity of the entropy density. This is still true in relativistic thermodynamics for a privileged entropy density which is the entropy density of the rest frame for non-degenerate gases.

On general features of warm dark matter with reduced relativistic gas

Science.gov (United States)

Hipólito-Ricaldi, W. S.; vom Marttens, R. F.; Fabris, J. C.; Shapiro, I. L.; Casarini, L.

2018-05-01

Reduced relativistic gas (RRG) is a useful approach to describe the warm dark matter (WDM) or the warmness of baryonic matter in the approximation when the interaction between the particles is irrelevant. The use of Maxwell distribution leads to the complicated equation of state of the Jüttner model of relativistic ideal gas. The RRG enables one to reproduce the same physical situation but in a much simpler form. For this reason RRG can be a useful tool for the theories with some sort of a "new Physics". On the other hand, even without the qualitatively new physical implementations, the RRG can be useful to describe the general features of WDM in a model-independent way. In this sense one can see, in particular, to which extent the cosmological manifestations of WDM may be dependent on its Particle Physics background. In the present work RRG is used as a complementary approach to derive the main observational features for the WDM in a model-independent way. The only assumption concerns a non-negligible velocity v for dark matter particles which is parameterized by the warmness parameter b. The relatively high values of b ( b^2˜ 10^{-6}) erase the radiation (photons and neutrinos) dominated epoch and cause an early warm matter domination after inflation. Furthermore, RRG approach enables one to quantify the lack of power in linear matter spectrum at small scales and in particular, reproduces the relative transfer function commonly used in context of WDM with accuracy of ≲ 1%. A warmness with b^2≲ 10^{-6} (equivalent to v≲ 300 km/s) does not alter significantly the CMB power spectrum and is in agreement with the background observational tests.

Quasiparticle method in relativistic mean-field theories of nuclear structure

International Nuclear Information System (INIS)

Ai, H.

1988-01-01

In recent years, in order to understand the success of Dirac phenomenology, relativistic Brueckner-Hartree-Fock (RBHF) theory has been developed. This theory is a relativistic many-body theory of nuclear structure. Based upon the RBHF theory, which is characterized as having no free parameters other than those introduced in fitting free-space nucleon-nucleon scattering data, we construct an effective interaction. This interaction, when treated in a relativistic Hartree-Fock approximation, reproduces, rather accurately, the nucleon self-energy in nuclear matter, Migdal parameters obtained via relativistic Brueckner-Hartree-Fock calculations, and the saturation curves calculated with the full relativistic Brueckner-Hartree-Fock theory. This effective interaction is constructed by adding a number of pseudoparticles to the mesons used to construct one-boson-exchange (OBE) models of the nuclear force. The pseudoparticles have relatively large masses and either real or imaginary coupling constants. (For example, exchange of a pseudo-sigma with an imaginary coupling constant has the effect of reducing the scalar attraction arising from sigma exchange, while exchange of a pseudo-omega with an imaginary coupling constant has the effect of reducing the repulsion arising from omega exchange. The terms beyond the Born term in the case of pion exchange are well simulated by pseudo-sigma exchange with a real coupling constant.) The effective interaction constructed here may be used for calculations of the properties of finite nuclei in a relativistic Hartree-Fock approximation

Relativistic theory of electron-impact ionization

International Nuclear Information System (INIS)

Rosenberg, Leonard

2010-01-01

A relativistic version of an earlier, non-relativistic, formulation of the theory of ionization of an atomic system by electron impact is presented. With a time-independent resolvent operator taken as the basis for the dynamics, a wave equation is derived for a system with open channels consisting of two positive-energy electrons in an external field generated by the residual ion. Virtual intermediate states can be accounted for by the effective Hamiltonian that appears in the wave equation and which in principle may be constructed perturbatively. The asymptotic form of the wavefunction, modified by the effects of the long-range Coulomb interactions of the two electrons in the external field, is derived. These electrons are constrained, by projection operators which appear naturally in the theory, to propagate in positive-energy states only. The long-range Coulomb effects take the form of phase factors similar to those that are found in the non-relativistic version of the theory. With the boundary conditions established, an integral identity for the ionization amplitude is derived, and used to set up a distorted-wave Born expansion for the transition amplitude involving Coulomb-modified propagating waves.

Particle-in-cell simulations of plasma accelerators and electron-neutral collisions

Directory of Open Access Journals (Sweden)

David L. Bruhwiler

2001-10-01

Full Text Available We present 2D simulations of both beam-driven and laser-driven plasma wakefield accelerators, using the object-oriented particle-in-cell code XOOPIC, which is time explicit, fully electromagnetic, and capable of running on massively parallel supercomputers. Simulations of laser-driven wakefields with low \\(∼10^{16} W/cm^{2}\\ and high \\(∼10^{18} W/cm^{2}\\ peak intensity laser pulses are conducted in slab geometry, showing agreement with theory and fluid simulations. Simulations of the E-157 beam wakefield experiment at the Stanford Linear Accelerator Center, in which a 30 GeV electron beam passes through 1 m of preionized lithium plasma, are conducted in cylindrical geometry, obtaining good agreement with previous work. We briefly describe some of the more significant modifications to XOOPIC required by this work, and summarize the issues relevant to modeling relativistic electron-neutral collisions in a particle-in-cell code.

Optical analogue of relativistic Dirac solitons in binary waveguide arrays

Energy Technology Data Exchange (ETDEWEB)

Tran, Truong X., E-mail: truong.tran@mpl.mpg.de [Department of Physics, Le Quy Don University, 236 Hoang Quoc Viet str., 10000 Hanoi (Viet Nam); Max Planck Institute for the Science of Light, Günther-Scharowsky str. 1, 91058 Erlangen (Germany); Longhi, Stefano [Department of Physics, Politecnico di Milano and Istituto di Fotonica e Nanotecnologie del Consiglio Nazionale delle Ricerche, Piazza L. da Vinci 32, I-20133 Milano (Italy); Biancalana, Fabio [Max Planck Institute for the Science of Light, Günther-Scharowsky str. 1, 91058 Erlangen (Germany); School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh (United Kingdom)

2014-01-15

We study analytically and numerically an optical analogue of Dirac solitons in binary waveguide arrays in the presence of Kerr nonlinearity. Pseudo-relativistic soliton solutions of the coupled-mode equations describing dynamics in the array are analytically derived. We demonstrate that with the found soliton solutions, the coupled mode equations can be converted into the nonlinear relativistic 1D Dirac equation. This paves the way for using binary waveguide arrays as a classical simulator of quantum nonlinear effects arising from the Dirac equation, something that is thought to be impossible to achieve in conventional (i.e. linear) quantum field theory. -- Highlights: •An optical analogue of Dirac solitons in nonlinear binary waveguide arrays is suggested. •Analytical solutions to pseudo-relativistic solitons are presented. •A correspondence of optical coupled-mode equations with the nonlinear relativistic Dirac equation is established.

Future X-ray Polarimetry of Relativistic Accelerators: Pulsar Wind Nebulae and Supernova Remnants

Directory of Open Access Journals (Sweden)

Niccolò Bucciantini

2018-03-01

Full Text Available Supernova remnants (SNRs and pulsar wind nebulae (PWNs are among the most significant sources of non-thermal X-rays in the sky, and the best means by which relativistic plasma dynamics and particle acceleration can be investigated. Being strong synchrotron emitters, they are ideal candidates for X-ray polarimetry, and indeed the Crab nebula is up to present the only object where X-ray polarization has been detected with a high level of significance. Future polarimetric measures will likely provide us with crucial information on the level of turbulence that is expected at particle acceleration sites, together with the spatial and temporal coherence of magnetic field geometry, enabling us to set stronger constraints on our acceleration models. PWNs will also allow us to estimate the level of internal dissipation. I will briefly review the current knowledge on the polarization signatures in SNRs and PWNs, and I will illustrate what we can hope to achieve with future missions such as IXPE/XIPE.

General Relativistic Calculations for White Dwarf Stars

OpenAIRE

Mathew, Arun; Nandy, Malay K.

2014-01-01

The mass-radius relations for white dwarf stars are investigated by solving the Newtonian as well as Tolman-Oppenheimer-Volkoff (TOV) equations for hydrostatic equilibrium assuming the electron gas to be non-interacting. We find that the Newtonian limiting mass of $1.4562M_\\odot$ is modified to $1.4166M_\\odot$ in the general relativistic case for $^4_2$He (and $^{12}_{\\ 6}$C) white dwarf stars. Using the same general relativistic treatment, the critical mass for $^{56}_{26}$Fe white dwarf is ...

Relativistic klystron research for high gradient accelerators

International Nuclear Information System (INIS)

Allen, M.A.; Callin, R.S.; Deruyter, H.

1988-06-01

Relativistic klystrons are being developed as a power source for high gradient accelerator applications which include large linear electron--positron colliders, compact accelerators, and FEL sources. We have attained 200MW peak power at 11.4 GHz from a relativistic klystron, and 140 MV/m longitudinal gradient in a short 11.4 GHz accelerator section. We report here on the design of our first klystrons, the results of our experiments so far, and some of our plans for the near future. 5 refs., 7 figs

Yang-Mills analogs of general-relativistic solutions

International Nuclear Information System (INIS)

Singlton, D.

1998-01-01

Some solutions of Yang-Mills equations, which can be found with the use of the general relativistic theory and Yang-Mills theory, are discussed. Some notes concerning possible physical sense of these solutions are made. Arguments showing that some of such solutions in the Yang-Mills theory (similar to the general relativistic ones) may be connected with the confinement phenomenon are given in particular. The motion of probe particles located into the phonon potential similar to the Schwarz-Child one is briefly discussed for this purpose [ru

On the relativistic Vlasov equation in guiding-center coordinates

International Nuclear Information System (INIS)

Salimullah, M.; Chaudhry, M.B.; Hassan, M.H.A.

1989-11-01

The relativistic Vlasov equation has been expressed in terms of the guiding-center coordinates in a hot magnetized plasma. It is noted that the relativistic effect reduces the cyclotron resonance frequency for electrostatic and electromagnetic waves propagating transverse to the direction of the static magnetic field in the plasma. (author). 4 refs

Relativistic tunneling through two successive barriers

International Nuclear Information System (INIS)

Lunardi, Jose T.; Manzoni, Luiz A.

2007-01-01

We study the relativistic quantum mechanical problem of a Dirac particle tunneling through two successive electrostatic barriers. Our aim is to study the emergence of the so-called generalized Hartman effect, an effect observed in the context of nonrelativistic tunneling as well as in its counterparts and which is often associated with the possibility of superluminal velocities in the tunneling process. We discuss the behavior of both the phase (or group) tunneling time and the dwell time, and show that in the limit of opaque barriers the relativistic theory also allows the emergence of the generalized Hartman effect. We compare our results with the nonrelativistic ones and discuss their interpretation

Kinematics of a relativistic particle with de Sitter momentum space

International Nuclear Information System (INIS)

Arzano, Michele; Kowalski-Glikman, Jerzy

2011-01-01

We discuss kinematical properties of a free relativistic particle with deformed phase space in which momentum space is given by (a submanifold of) de Sitter space. We provide a detailed derivation of the action, Hamiltonian structure and equations of motion for such a free particle. We study the action of deformed relativistic symmetries on the phase space and derive explicit formulae for the action of the deformed Poincare group. Finally we provide a discussion on parametrization of the particle worldlines stressing analogies and differences with ordinary relativistic kinematics.

Relativistic bound state wave functions

International Nuclear Information System (INIS)

Micu, L.

2005-01-01

A particular method of writing the bound state wave functions in relativistic form is applied to the solutions of the Dirac equation with confining potentials in order to obtain a relativistic description of a quark antiquark bound system representing a given meson. Concerning the role of the effective constituent in the present approach we first observe that without this additional constituent we couldn't expand the bound state wave function in terms of products of free states. Indeed, we notice that if the wave function depends on the relative coordinates only, all the expansion coefficients would be infinite. Secondly we remark that the effective constituent enabled us to give a Lorentz covariant meaning to the potential energy of the bound system which is now seen as the 4th component of a 4-momentum. On the other side, by relating the effective constituent to the quantum fluctuations of the background field which generate the binding, we provided a justification for the existence of some spatial degrees of freedom accompanying the interaction potential. These ones, which are quite unusual in quantum mechanics, in our model are the natural consequence of the the independence of the quarks and can be seen as the effect of the imperfect cancellation of the vector momenta during the quantum fluctuations. Related with all these we remark that the adequate representation for the relativistic description of a bound system is the momentum representation, because of the transparent and easy way of writing the conservation laws and the transformation properties of the wave functions. The only condition to be fulfilled is to find a suitable way to take into account the potential energy of the bound system. A particular feature of the present approach is that the confining forces are due to a kind of glue where both quarks are embedded. This recalls other bound state models where the wave function is factorized in terms of constituent wave functions and the confinement is

A multi-subunit Chlamydia vaccine inducing neutralizing antibodies and strong IFN-γ(+) CMI responses protects against a genital infection in minipigs

DEFF Research Database (Denmark)

Bøje, Sarah; Olsen, Anja Weinreich; Erneholm, Karin

2016-01-01

Chlamydia is the most widespread sexually transmitted bacterial disease and a prophylactic vaccine is highly needed. Ideally, this vaccine is required to induce a combined response of Th1 cell-mediated immune (CMI) response in concert with neutralizing antibodies. Using a novel Göttingen minipig...... animal model, we evaluated the immunogenicity and efficacy of a multi-subunit vaccine formulated in the strong Th1-inducing adjuvant CAF01. We evaluated a mixture of two fusion proteins (Hirep1 and CTH93) designed to promote either neutralizing antibodies or cell-mediated immunity, respectively. Hirep1...

Diffraction radiation from relativistic particles

CERN Document Server

Potylitsyn, Alexander Petrovich; Strikhanov, Mikhail Nikolaevich; Tishchenko, Alexey Alexandrovich

2010-01-01

This book deals with diffraction radiation, which implies the boundary problems of electromagnetic radiation theory. Diffraction radiation is generated when a charged particle moves in a vacuum near a target edge. Diffraction radiation of non-relativistic particles is widely used to design intense emitters in the cm wavelength range. Diffraction radiation from relativistic charged particles is important for noninvasive beam diagnostics and design of free electron lasers based on Smith-Purcell radiation which is diffraction radiation from periodic structures. Different analytical models of diffraction radiation and results of recent experimental studies are presented in this book. The book may also serve as guide to classical electrodynamics applications in beam physics and electrodynamics. It can be of great use for young researchers to develop skills and for experienced scientists to obtain new results.

Diffraction radiation from relativistic particles

International Nuclear Information System (INIS)

Potylitsyn, Alexander Petrovich; Ryazanov, Mikhail Ivanovich; Strikhanov, Mikhail Nikolaevich; Tishchenko, Alexey Alexandrovich

2010-01-01

This book deals with diffraction radiation, which implies the boundary problems of electromagnetic radiation theory. Diffraction radiation is generated when a charged particle moves in a vacuum near a target edge. Diffraction radiation of non-relativistic particles is widely used to design intense emitters in the cm wavelength range. Diffraction radiation from relativistic charged particles is important for noninvasive beam diagnostics and design of free electron lasers based on Smith-Purcell radiation which is diffraction radiation from periodic structures. Different analytical models of diffraction radiation and results of recent experimental studies are presented in this book. The book may also serve as guide to classical electrodynamics applications in beam physics and electrodynamics. It can be of great use for young researchers to develop skills and for experienced scientists to obtain new results. (orig.)

Ultra-relativistic heavy-ion physics with AFTER@LHC

DEFF Research Database (Denmark)

Rakotozafindrabe, A.; Arnaldi, R.; Brodsky, Stanley

2013-01-01

We outline the opportunities for ultra-relativistic heavy–ion physics which are offered by a next generation and multi-purpose fixed-target experiment exploiting the proton and ion LHC beams extracted by a bent crystal.......We outline the opportunities for ultra-relativistic heavy–ion physics which are offered by a next generation and multi-purpose fixed-target experiment exploiting the proton and ion LHC beams extracted by a bent crystal....

Soft ideal topological space and mixed fuzzy soft ideal topological space

Directory of Open Access Journals (Sweden)

Manash Borah

2019-01-01

Full Text Available In this paper we introduce fuzzy soft ideal and mixed fuzzy soft ideal topological spaces and some properties of this space. Also we introduce fuzzy soft $I$-open set, fuzzy soft $\\alpha$-$I$-open set, fuzzy soft pre-$I$-open set, fuzzy soft semi-$I$-open set and fuzzy soft $\\beta$-$I$-open set and discuss some of their properties.

Thermal relaxation time of a mixture of relativistic electrons and neutrinos

International Nuclear Information System (INIS)

Herrera, M.A.; Hacyan, S.

1987-01-01

The interaction between the components of a relativistic binary mixture is studied by means of a fully covariant formalism. Assuming both components to differ slightly in temperature, an application of the relativistic Boltzmann equation yields general expressions for the energy transfer rate and for the relaxation time of the system. The resulting relation is then applied to a mixture of relativistic electrons and neutrinos to obtain numerical values of its relaxation time. (author)

Relativistic Outflows from ADAFs

Science.gov (United States)

Becker, Peter; Subramanian, Prasad; Kazanas, Demosthenes

2001-04-01

Advection-dominated accretion flows (ADAFs) have a positive Bernoulli parameter, and are therefore gravitationally bound. The Newtonian ADAF model has been generalized recently to obtain the ADIOS model that includes outflows of energy and angular momentum, thereby allowing accretion to proceed self-consistently. However, the utilization of a Newtonian gravitational potential limits the ability of this model to describe the inner region of the disk, where any relativistic outflows are likely to originate. In this paper we modify the ADIOS scenario to incorporate a seudo - Newtonian potential, which approximates the effects of general relativity. The analysis yields a unique, self - similar solution for the structure of the coupled disk/wind system. Interesting features of the new solution include the relativistic character of the outflow in the vicinity of the radius of marginal stability, which represents the inner edge of the quasi-Keplerian disk in our model. Our self - similar model may therefore help to explain the origin of relativistic jets in active galaxies. At large distances the radial dependence of the accretion rate approachs the unique form dot M ∝ r^1/2, with an associated density variation given by ρ ∝ r-1. This density variation agrees with that implied by the dependence of the X-ray hard time lags on the Fourier frequency for a number of accreting galactic black hole candidates. While intriguing, the results of our self-similar model need to be confirmed in the future by incorporating a detailed physical description of the energization mechanism that drives the outflow, which is likely to be powered by the shear of the underlying accretion disk.

RELATIVISTIC MEASUREMENTS FROM TIMING THE BINARY PULSAR PSR B1913+16

Energy Technology Data Exchange (ETDEWEB)

Weisberg, J. M.; Huang, Y., E-mail: jweisber@carleton.edu [Department of Physics and Astronomy, Carleton College, Northfield, MN 55057 (United States)

2016-09-20

We present relativistic analyses of 9257 measurements of times-of-arrival from the first binary pulsar, PSR B1913+16, acquired over the last 35 years. The determination of the “Keplerian” orbital elements plus two relativistic terms completely characterizes the binary system, aside from an unknown rotation about the line of sight, leading to a determination of the masses of the pulsar and its companion: 1.438 ± 0.001 M {sub ☉} and 1.390 ± 0.001 M {sub ☉}, respectively. In addition, the complete system characterization allows for the creation of relativistic gravitation test by comparing measured and predicted sizes of various relativistic phenomena. We find that the ratio of the observed orbital period decrease caused by gravitational wave damping (corrected by a kinematic term) to the general relativistic prediction is 0.9983 ± 0.0016, thereby confirms the existence and strength of gravitational radiation as predicted by general relativity. For the first time in this system, we have also successfully measured the two parameters characterizing the Shapiro gravitational propagation delay, and found that their values are consistent with general relativistic predictions. For the first time in any system, we have also measured the relativistic shape correction to the elliptical orbit, δ {sub θ} , although its intrinsic value is obscured by currently unquantified pulsar emission beam aberration. We have also marginally measured the time derivative of the projected semimajor axis, which, when improved in combination with beam aberration modeling from geodetic precession observations, should ultimately constrain the pulsar’s moment of inertia.

Consistent resolution of some relativistic quantum paradoxes

International Nuclear Information System (INIS)

Griffiths, Robert B.

2002-01-01

A relativistic version of the (consistent or decoherent) histories approach to quantum theory is developed on the basis of earlier work by Hartle, and used to discuss relativistic forms of the paradoxes of spherical wave packet collapse, Bohm's formulation of the Einstein-Podolsky-Rosen paradox, and Hardy's paradox. It is argued that wave function collapse is not needed for introducing probabilities into relativistic quantum mechanics, and in any case should never be thought of as a physical process. Alternative approaches to stochastic time dependence can be used to construct a physical picture of the measurement process that is less misleading than collapse models. In particular, one can employ a coarse-grained but fully quantum-mechanical description in which particles move along trajectories, with behavior under Lorentz transformations the same as in classical relativistic physics, and detectors are triggered by particles reaching them along such trajectories. States entangled between spacelike separate regions are also legitimate quantum descriptions, and can be consistently handled by the formalism presented here. The paradoxes in question arise because of using modes of reasoning which, while correct for classical physics, are inconsistent with the mathematical structure of quantum theory, and are resolved (or tamed) by using a proper quantum analysis. In particular, there is no need to invoke, nor any evidence for, mysterious long-range superluminal influences, and thus no incompatibility, at least from this source, between relativity theory and quantum mechanics

Electronic structure of molecules using relativistic effective core potentials

International Nuclear Information System (INIS)

Hay, P.J.

1981-01-01

Starting with one-component Cowan-Griffin relativistic Hartree-Fock orbitals, which successfully incorporate the mass-velocity and Darwin terms present in more complicated wavefunctions such as Dirac-Hartree-Fock, one can derive relativistic effective core potentials (RECP's) to carry out molecular calculations. These potentials implicitly include the dominant relativistic terms for molecules while allowing one to use the traditional quantum chemical techniques for studying the electronic structure of molecules. The effects of spin-orbit coupling can then be included using orbitals from such calculations using an effective 1-electron, 1-center spin-orbit operator. Applications to molecular systems involving heavy atoms, show good agreement with available spectroscopic data on molecular geometries and excitation energies

Cosmic gamma-ray burst from intergalactic relativistic dust grains

International Nuclear Information System (INIS)

Dasgupta, A.K.

1979-01-01

Charged dust grains of radii a approximately 3 x 10 -6 approximately 3 x 10 -5 cm may acquire relativistic energy (>10 18 eV) in the intergalactic medium. In order to attain relativistic energy, dust grains have to move in and out ('scattering') of the magnetic field of the medium. A relativistic grain of radius a -5 cm with Lorentz factor γ approximately 10 3 approaching the Earth will break up either due to electrostatic charge or due to sputtering about 150 approximately 100 km, and may scatter solar photons via a fluorescence process. Dust grains may also melt into droplets in the solar vicinity and may contribute towards observed gamma-ray bursts. (Auth.)

Canonical quantization of spinning relativistic particle in external backgrounds

Energy Technology Data Exchange (ETDEWEB)

Gavrilov, S.P. [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil); Gitman, D.M. [Sao Paulo Univ. (USP), SP (Brazil). Inst. de Fisica

2000-07-01

Full text follows: We revise the problem of the quantization of spinning relativistic particle pseudoclassical model, using a modified consistent canonical scheme. It allows one not only to include arbitrary electromagnetic and gravitational backgrounds in the consideration but to get in course of the quantization a consistent relativistic quantum mechanics, which reproduces literally the behavior of the one-particle sector of quantized spinor field. In particular, in a physical sector of the Hilbert space a complete positive spectrum of energies of relativistic particles and antiparticles is reproduced. Requirement to maintain all classical symmetries under the coordinate transformations and under U(1) transformations allows one to realize operator algebra without any ambiguities. (author)

Present status of the theoretical relativistic plasma SHF electronics

International Nuclear Information System (INIS)

Kuzelev, M.V.; Rukhadze, A.A.

2000-01-01

Paper presents a review of theoretical investigations into powerful sources of SHF waves grounded on the forced emission of relativistic electron beams in plasma wave guides and resonator. Emission sources operating under amplification of a certain inlet signal and under generation mode were studied. Two mechanisms of forced emission: resonance Cherenkov radiation of relativistic electron beams in plasma and nonresonance Pierce emission resulting from evolution of high-frequency Pierce instability, were studied. Paper discusses theoretical problems only, all evaluations and calculations are made for the parameters of the exact experiments, the theoretical results are compared with the available experimental data. Factors affecting formation of spectrum of waves excited by relativistic electron beam in plasma systems are discussed [ru

In-medium relativistic kinetic theory and nucleon-meson systems

International Nuclear Information System (INIS)

Morawetz, K.; Kremp, D.

1995-01-01

Within the σ-ω model of coupled nucleonmeson systems, a generalized relativistic Lennard-Balescu-equation is presented resulting from a relativistic random phase approximation (RRPA). This provides a systematic derivation of relativistic transport equations in the frame of nonequilibrium Green's function technique including medium effects as well as fluctuation effects. It contains all possible processes due to one-meson exchange and special attention is kept to the off-shell character of the particles. As a new feature of many-particle effects, processes are possible, which can be interpreted as particle creation and annihilation due to in-medium one-meson exchange. In-medium cross sections are obtained from the generalized derivation of collision integrals, which possess complete crossing symmetries. (orig.)

Radiatively-suppressed spherical accretion under relativistic radiative transfer

Science.gov (United States)

Fukue, Jun

2018-03-01

We numerically examine radiatively-suppressed relativistic spherical accretion flows on to a central object with mass M under Newtonian gravity and special relativity. We simultaneously solve both the relativistic radiative transfer equation and the relativistic hydrodynamical equations for spherically symmetric flows under the double iteration process in the case of the intermediate optical depth. We find that the accretion flow is suppressed, compared with the freefall case in the nonrelativistic regime. For example, in the case of accretion on to a luminous core with accretion luminosity L*, the freefall velocity v normalized by the speed of light c under the radiative force in the nonrelativistic regime is β (\\hat{r}) = v/c = -√{(1-Γ _*)/(\\hat{r}+1-Γ _*)}, where Γ* (≡ L*/LE, LE being the Eddington luminosity) is the Eddington parameter and \\hat{r} (= r/rS, rS being the Schwarzschild radius) the normalized radius, whereas the infall speed at the central core is ˜0.7β(1), irrespective of the mass-accretion rate. This is due to the relativistic effect; the comoving flux is enhanced by the advective flux. We briefly examine and discuss an isothermal case, where the emission takes place in the entire space.

OPE convergence in non-relativistic conformal field theories

Energy Technology Data Exchange (ETDEWEB)

Goldberger, Walter D.; Khandker, Zuhair University; Prabhu, Siddharth [Department of Physics, Yale University,New Haven, CT 06511 (United States); Physics Department, Boston University,Boston, MA 02215 (United States)

2015-12-09

Motivated by applications to the study of ultracold atomic gases near the unitarity limit, we investigate the structure of the operator product expansion (OPE) in non-relativistic conformal field theories (NRCFTs). The main tool used in our analysis is the representation theory of charged (i.e. non-zero particle number) operators in the NRCFT, in particular the mapping between operators and states in a non-relativistic “radial quantization” Hilbert space. Our results include: a determination of the OPE coefficients of descendant operators in terms of those of the underlying primary state, a demonstration of convergence of the (imaginary time) OPE in certain kinematic limits, and an estimate of the decay rate of the OPE tail inside matrix elements which, as in relativistic CFTs, depends exponentially on operator dimensions. To illustrate our results we consider several examples, including a strongly interacting field theory of bosons tuned to the unitarity limit, as well as a class of holographic models. Given the similarity with known statements about the OPE in SO(2,d) invariant field theories, our results suggest the existence of a bootstrap approach to constraining NRCFTs, with applications to bound state spectra and interactions. We briefly comment on a possible implementation of this non-relativistic conformal bootstrap program.

Impossibility of an acyclic relativistic electric motor

Energy Technology Data Exchange (ETDEWEB)

Spavieri, G [Universidad de Los Andes, Merida (Venezuela); Cavalleri, G [Milan Univ. (Italy). Ist. di Fisica; Spinelli, G [Padua Univ. (Italy). Ist. di Matematica Applicata

1981-02-11

The relativistic torque acting on a circuit carrying a current and having a uniform translatory motion in a constant and uniform electric field would seem to suggest the possibility of an acyclic relativistic electric motor. However, the net effect on the side parallel to the rotation axis is exactly balanced by the variation of the angular momentum (in the case of an insulating circuit transporting electric charges) or by the external moment due to the magnetic field (in the case of a conducting circuit) acting on the two sides perpendicular to the rotation axis.

Relativistic quantum mechanics of leptons and fields

International Nuclear Information System (INIS)

Grandy, W.T. Jr.

1991-01-01

This book serves as an advanced text on the Dirac theory, and provides a monograph summarizing the description of relativistic quantum mechanics and quantum electrodynamics as classical field theories. It presents a broad, detailed, and up-to-date exposition of relativistic quantum mechanics, including the two-body problem. It also demonstrates the extent to which the behavior of stable particles and their interactions can be understood without introducing operator (second-quantized) fields. The subsequent difficulties are studied in detail and possible resolutions are presented through quantum field theory

Relativistic Celestial Mechanics of the Solar System

CERN Document Server

Kopeikin, Sergei; Kaplan, George

2011-01-01

This authoritative book presents the theoretical development of gravitational physics as it applies to the dynamics of celestial bodies and the analysis of precise astronomical observations. In so doing, it fills the need for a textbook that teaches modern dynamical astronomy with a strong emphasis on the relativistic aspects of the subject produced by the curved geometry of four-dimensional spacetime. The first three chapters review the fundamental principles of celestial mechanics and of special and general relativity. This background material forms the basis for understanding relativistic r

Constraints on the cosmological relativistic energy density

International Nuclear Information System (INIS)

Zentner, Andrew R.; Walker, Terry P.

2002-01-01

We discuss bounds on the cosmological relativistic energy density as a function of redshift, reviewing the big bang nucleosynthesis and cosmic microwave background bounds, updating bounds from large scale structure, and introducing a new bound from the magnitude-redshift relation for type Ia supernovae. We conclude that the standard and well-motivated assumption that relativistic energy is negligible during recent epochs is not necessitated by extant data. We then demonstrate the utility of these bounds by constraining the mass and lifetime of a hypothetical massive big bang relic particle

Relativistic deuteron wave function on light front

International Nuclear Information System (INIS)

Karmanov, V.A.

1980-01-01

In the framework of the one boson exchange model the approximate analytical expression for the deuteron wave function (WF) at relativistic relative momenta is obtained. WF depends on extra variable having the form of a unit vector and is determined by six functions instead of two ones (S-and D-waves) in the nonrelativistic case. At moderate momenta the WF is matched with WF in the Reid model. It is emphasized the importance of indication of the qualitative observed phenomena associated with change of parametrization and spin structure of relativistic deuteron WF

Development of a 2 MW relativistic backward wave oscillator

Indian Academy of Sciences (India)

In this paper, a high power relativistic backward wave oscillator (BWO) experiment is reported. A 230 keV, 2 kA, 150 ns relativistic electron beam is generated using a Marx generator. The beam is then injected into a hollow rippled wall metallic cylindrical tube that forms a slow wave structure. The beam is guided using an ...

Remarks on the relativistic magnetohydrodynamics of an anisotropic fluid

International Nuclear Information System (INIS)

Ignat, M.

1980-01-01

Considering a pressure tensor of a general form, a relativistic rarefied, anisotropic, infinite electrically conducting and nondissipative plasma is studied. For this purpose, the method of the orthonormal frame of reference is used. The choice of the frame of reference is made adequately to the problem. Some thermodynamical properties of such a relativistic, anisotropic plasma are also given. (author)

Hadron matrix elements of quark operators in the relativistic quark model

Energy Technology Data Exchange (ETDEWEB)

Bando, Masako; Toya, Mihoko [Kyoto Univ. (Japan). Dept. of Physics; Sugimoto, Hiroshi

1979-07-01

General formulae for evaluating matrix elements of two- and four-quark operators sandwiched by one-hadron states are presented on the basis of the relativistic quark model. Observed hadronic quantities are expressed in terms of those matrix elements of two- and four-quark operators. One observes various type of relativistic expression for the matrix elements which in the non-relativistic case reduce to simple expression of the so-called ''the wave function at the origin /sup +/psi(0)/sup +/''.

Lacunary ideal convergence of multiple sequences

Directory of Open Access Journals (Sweden)

Bipan Hazarika

2016-01-01

Full Text Available An ideal I is a family of subsets of N×N which is closed under taking finite unions and subsets of its elements. In this article, the concept of lacunary ideal convergence of double sequences has been introduced. Also the relation between lacunary ideal convergent and lacunary Cauchy double sequences has been established. Furthermore, the notions of lacunary ideal limit point and lacunary ideal cluster points have been introduced and find the relation between these two notions. Finally, we have studied the properties such as solidity, monotonic.

Dispersion formulae for waves in a magneto-active relativistic plasma

International Nuclear Information System (INIS)

Misra, P.; Mohanty, J.N.

1980-01-01

Dispersion formulae are derived for the transverse waves propagating through a collisionless magneto-active plasma in the direction of the magnetic field valid for relativistic as well as non-relativistic temperatures. Wave propagation under various limiting conditions of temperatures and magnetic field are discussed. (author)

Dispersion formulae for waves in a magneto-active relativistic plasma

Energy Technology Data Exchange (ETDEWEB)

Misra, P. (Ravenshaw Coll., Cuttack (India)); Mohanty, J.N. (F.M. College, Balasore (India). Dept. of Physics)

1980-12-01

Dispersion formulae are derived for the transverse waves propagating through a collisionless magneto-active plasma in the direction of the magnetic field valid for relativistic as well as non-relativistic temperatures. Wave propagation under various limiting conditions of temperatures and magnetic field are discussed.

Nonlocal relativistic diffusion (NoRD) model of cosmic ray propagation

International Nuclear Information System (INIS)

Uchaikin, V V; Sibatov, R T

2017-01-01

The problem of physical interpretation of the nonlocal relativistic diffusion (NoRD model) for cosmic ray transport in the Galaxy is discussed. The model accounts for the turbulent character of the interstellar medium and the relativistic principle of the speed limitation. Involving fractional calculus and non-Gaussian Lévy statistics yields numerical results compatible with observation data. A special attention is paid to the knee problem. The relativistic speed limit requirement steepens theoretical background spectrum at certain energies, and the position of the break, its sharpness and slopes of asymptotes depend on D α ( E ) and α . (paper)

On the kinetic theory of parametric resonance in relativistic plasma

International Nuclear Information System (INIS)

El-Ashry, M.Y.

1982-08-01

The instability of relativistic hot plasma located in high-frequency external electric field is studied. The dispersion relation, in the case when the plasma electrons have relativistic oscillatory motion, is obtained. It is shown that if the electron Deby's radius is less than the wave length of plasma oscillation and far from the resonance on the overtones of the external field frequency, the oscillation build-up is possible. It is also shown that taking into account the relativistic motion of electrons leads to a considerable decrease in the frequency at which the parametric resonance takes place. (author)