1,048 research outputs found

    A scaling law for the dust cloud in radio frequency discharge under microgravity conditions

    Full text link
    We employ the approximation of overlapped scattering potentials of charged dust particles exposed to streaming ions to deduce the "equation of state" for a stationary dust cloud in the radio frequency discharge apart from the void dust boundary. The obtained equation defines the potential of a dust particle as a function of the ion number density, the mass of a carrier gas atom, and the electron temperature. A scaling law that relates the particle number density to the particle radius and electron temperature in different systems is formulated. Based on the proposed approach the radius of a cavity around a large particle in the bulk of a cloud is estimated. The results of calculation are in a reasonable agreement with the experimental data available in literature.Comment: 10 pages, 7 figures, and 1 tabl

    Thermodynamic Properties of Correlated Strongly Degenerate Plasmas

    Full text link
    An efficient numerical approach to equilibrium properties of strongly coupled systems which include a subsystem of fermionic quantum particles and a subsystem of classical particles is presented. It uses an improved path integral representation of the many-particle density operator and allows to describe situations of strong coupling and strong degeneracy, where analytical theories fail. A novel numerical method is developed, which allows to treat degenerate systems with full account of the spin scatistics. Numerical results for thermodynamic properties such as internal energy, pressure and pair correlation functions are presented over a wide range of degeneracy parameter.Comment: 8 pages, 4 figures, uses sprocl.sty (included) to be published in "Progress in Nonequilibrium Green's functions", M. Bonitz (Ed.), World Scientific 200

    Peculiarities of momentum distribution functions of strongly correlated charged fermions

    Full text link
    The new numerical version of the Wigner approach to quantum mechanics for treatment thermodynamic properties of strongly coupled systems of particles has been developed for extreme conditions, when analytical approximations obtained in different kind of perturbation theories can not be applied. Explicit analytical expression of the Wigner function has been obtained in linear and harmonic approximations. Fermi statistical effects are accounted by effective pair pseudopotential depending on coordinates, momenta and degeneracy parameter of particles and taking into account Pauli blocking of fermions. The new quantum Monte-Carlo method for calculations of average values of arbitrary quantum operators has been proposed. Calculations of the momentum distribution function of the degenerate ideal Fermi gas have been carried out for testing the developed approach. Comparison of obtained momentum distribution function of strongly correlated Coulomb systems of particles with Maxwell -- Boltzmann and Fermi distributions shows the significant influence of interparticle interaction both at small momenta and in the high energy quantum 'tails'.Comment: 14 pages, 6 captured figures. arXiv admin note: text overlap with arXiv:1702.0409

    Onset of cavity deformation upon subsonic motion of a projectile in a fluid complex plasma

    Full text link
    We study deformation of a cavity around a large projectile moving with subsonic velocity in the cloud of small dust particles. To solve this problem, we employ the Navier--Stokes equation for a compressible fluid with due regard for friction between dust particles and atoms of neutral gas. The solutions shows that due to friction, the pressure of dust cloud at the boundary of the cavity behind the projectile can become negative, which entails formation of a microscopic void free from dust particles -- the cavity deformation. Corresponding threshold velocity is calculated, which is found to decrease with increasing cavity size. Measurement of such velocity makes it possible to estimate the static pressure inside the dust cloud.Comment: 7 pages, 3 figure

    Thermodynamic properties and electrical conductivity of strongly correlated plasma media

    Full text link
    We study thermodynamic properties and the electrical conductivity of dense hydrogen and deuterium using three methods: classical reactive Monte Carlo (REMC), direct path integral Monte Carlo (PIMC) and a quantum dynamics method in the Wigner representation of quantum mechanics. We report the calculation of the deuterium compression quasi-isentrope in good agreement with experiments. We also solve the Wigner-Liouville equation of dense degenerate hydrogen calculating the initial equilibrium state by the PIMC method. The obtained particle trajectories determine the momentum-momentum correlation functions and the electrical conductivity and are compared with available theories and simulations

    Color path-integral Monte Carlo simulations of quark-gluon plasma

    Full text link
    Thermodynamic properties of a strongly coupled quark-gluon plasma (QGP) of constituent quasiparticles are studied by a color path-integral Monte Carlo simulations (CPIMC). For our simulations we have presented QGP partition function in the form of color path integral with new relativistic measure instead of Gaussian one used in Feynman and Wiener path integrals. For integration over color variable we have also developed procedure of sampling color variables according to the group SU(3) Haar measure. It is shown that this method is able to reproduce the available quantum lattice chromodynamics (QCD) data

    Correlation effects in partially ionized mass asymmetric electron-hole plasmas

    Full text link
    The effects of strong Coulomb correlations in dense three-dimensional electron-hole plasmas are studied by means of unbiased direct path integral Monte Carlo simulations. The formation and dissociation of bound states, such as excitons and bi-excitons is analyzed and the density-temperature region of their appearance is identified. At high density, the Mott transition to the fully ionized metallic state (electron-hole liquid) is detected. Particular attention is paid to the influence of the hole to electron mass ratio MM on the properties of the plasma. Above a critical value of about M=80 formation of a hole Coulomb crystal was recently verified [Phys. Rev. Lett. {\bf 95}, 235006 (2005)] which is supported by additional results. Results are related to the excitonic phase diagram of intermediate valent Tm[Se,Te], where large values of MM have been observed experimentally.Comment: slightly modified and shortened paper to appear in Physical Review E; contains more detailed presentation of theory (appendices

    Equation of state of strongly coupled quark--gluon plasma -- Path integral Monte Carlo results

    Full text link
    A strongly coupled plasma of quark and gluon quasiparticles at temperatures from 1.1Tc 1.1 T_c to 3Tc3 T_c is studied by path integral Monte Carlo simulations. This method extends previous classical nonrelativistic simulations based on a color Coulomb interaction to the quantum regime. We present the equation of state and find good agreement with lattice results. Further, pair distribution functions and color correlation functions are computed indicating strong correlations and liquid-like behavior
    corecore