# Journal of Plasma Physics Impact Factor & Information

Publisher: Cambridge University Press (CUP)

## Journal description

Journal of Plasma Physics publishes primary research articles in plasma physics both theoretical and experimental and its applications. Basic topics include the fundamental physics of plasmas ionization kinetic theory particle orbits stochastic dynamics wave propagation solitons stability shock waves transport heating and diagnostics. Applications include fusion laboratory plasmas and communications devices laser plasmas technological plasmas space physics and astrophysics.

## Impact Factor Rankings

2015 Impact Factor Available summer 2016 0.864 0.739 0.755 0.944 1.078 0.775 0.579 0.661 0.748 1.037 0.602 0.61 0.645 0.649 0.837 0.761 0.85 0.516 0.661 0.552 0.615 0.712 0.489

## Impact factor over time

Impact factor
.
Year

5-year impact 0.82 >10.0 0.26 0.00 0.33 Journal of Plasma Physics website Journal of plasma physics 0022-3778 1754745 Periodical, Internet resource Journal / Magazine / Newspaper, Internet Resource

## Publisher details

• Pre-print
• Author can archive a pre-print version
• Post-print
• Author can archive a post-print version
• Conditions
• Author's Pre-print on author's personal website, departmental website, social media websites, institutional repository, non-commercial subject-based repositories, such as PubMed Central, Europe PMC or arXiv
• Author's post-print on author's personal website on acceptance of publication
• Author's post-print on departmental website, institutional repository, non-commercial subject-based repositories, such as PubMed Central, Europe PMC or arXiv, after a 6 months embargo
• Publisher's version/PDF cannot be used
• Published abstract may be deposited
• Pre-print to record acceptance for publication
• Publisher copyright and source must be acknowledged with set statement
• Must link to publisher version
• Publisher last reviewed on 07/10/2014
• This policy is an exception to the default policies of 'Cambridge University Press (CUP)'
• Classification
green

## Publications in this journal

• ##### Article: Energetic electrons generated during solar flares
[Hide abstract]
ABSTRACT: The Sun is a giant particle accelerator. During solar flares, magnetic field energy stored in the corona is suddenly released and transferred to local heating of the coronal plasma, mass motions (e.g. jets) and the generation of energetic particles, i.e. electrons, protons and heavy ions. Basically, a flare occurs as a local enhancement of the emission of electromagnetic radiation from the radio up to the ${\it\gamma}$ -ray range on the Sun. That indicates the production of energetic electrons during flares. NASA’s RHESSI mission has the aim to investigate electron acceleration processes by studying the Sun’s X-ray and ${\it\gamma}$ -ray emission with high spatial, temporal and spectral resolution, i.e. by means of imaging spectroscopy. A substantial part of the energy released during a flare is carried by these energetic electrons. Apart from them, solar energetic particles, i.e. protons and heavy ions, and coronal mass ejections play an important role in the energy budget of a flare. Here, we focus on electron acceleration. The way in which $10^{36}$ electrons are accelerated up to energies beyond 30 keV is one of the open questions in solar physics. A flare is considered as the manifestation of magnetic reconnection in the solar corona. Which mechanisms lead to the production of energetic electrons in the magnetic reconnection region is discussed in this paper. Two of them are described in more detail.
Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815001166
• ##### Article: Parallel 3-D particle-in-cell modelling of charged ultrarelativistic beam dynamics
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ABSTRACT: We present a three-dimensional (3-D) particle-in-cell (PIC) model and parallel code for the self-consistent motion of charged ultrarelativistic beams ( ${\it\gamma}\sim 10^{3}{-}10^{5}$ ) in supercolliders. We use the 3-D set of Maxwell’s equations for the electromagnetic fields, and the Vlasov equation for the distribution function of the beam particles. The model incorporates automatically the longitudinal effects, which can play a significant role in the cases of super-high densities. We present numerical results for the dynamics of two focused ultrarelativistic beams with a size ratio 10:1:100. The results demonstrate high efficiency of the proposed computational methods and algorithms, which are applicable to a variety of problems in relativistic plasma physics.
Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815001178
• ##### Article: Critical densities for Korteweg–de Vries-like acoustic solitons in multi-ion plasmas
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ABSTRACT: A generic proof has been given that, for the acoustic mode with the highest velocity in a plasma comprising a number of fluid species and one kind of inertialess electrons, even though there can be critical densities (making the coefficient of the quadratic nonlinearity in a Korteweg–de Vries equation vanish), no supercritical densities exist (requiring the simultaneous annulment of both the quadratic and cubic nonlinearities in a reductive perturbation treatment). Similar conclusions hold upon expansion of the corresponding Sagdeev pseudopotential treatment. When there is only one (hot) electron species, the highest-velocity mode is an ion-acoustic one, but if there is an additional cool electron species, with its inertia taken into account, the highest-velocity mode is an electron-acoustic mode in a two-temperature plasma. The cool fluid species can have various polytropic pressure–density relations, including adiabatic and/or isothermal variations, whereas the hot inertialess electrons are modelled by extensions of the usual Boltzmann description that include non-thermal effects through Cairns, kappa or Tsallis distributions. Together, in this way quite a number of plasma models are covered. Unfortunately, there seems to be no equivalent generic statement for the slow modes, so that these have to be studied on a case-by-case basis, which for models with more than three species is far from straightforward, given the parameter ranges to be discussed.
Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815001282
• ##### Article: Axisymmetric global gravitational equilibrium for magnetized, rotating hot plasma
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ABSTRACT: We present analytic solutions for three-dimensional magnetized axisymmetric equilibria confining rotating hot plasma in a gravitational field. Our up–down symmetric solution to the full Grad–Shafranov equation can exhibit equatorial plane localization of the plasma density and current, resulting in disk equilibria for the plasma density. For very weak magnetic fields and high plasma pressure, we find strongly rotating thin plasma disk gravitational equilibria that satisfy strict Keplerian motion provided the gravitational energy is much larger than the plasma pressure, which must be large compared to the magnetic energy of the poloidal magnetic field. When the rotational energy exceeds the gravitational energy and it is larger than the plasma pressure, diffuse disk equilibrium solutions continue to exist provided the poloidal magnetic energy remains small. For stronger magnetic fields and lower plasma pressure and rotation, we can also find gravitational equilibria with strong localization to the equatorial plane. However, a toroidal magnetic field is almost always necessary to numerically verify these equilibria are valid solutions in the presence of gravity for the cases considered in Catto & Krasheninnikov ( J. Plasma Phys. , vol. 81, 2015, 105810301). In all cases both analytic and numerical results are presented.
Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815001245
• ##### Article: Effect of guide field on three-dimensional electron shear flow instabilities in electron current sheets
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ABSTRACT: We examine, in the limit of electron plasma ${\it\beta}_{e}\ll 1$ , the effect of an external guide field and current sheet thickness on the growth rates and nature of three-dimensional (3-D) unstable modes of an electron current sheet driven by electron shear flow. The growth rate of the fastest growing mode drops rapidly with current sheet thickness but increases slowly with the strength of the guide field. The fastest growing mode is tearing type only for thin current sheets (half-thickness ${\approx}d_{e}$ , where $d_{e}=c/{\it\omega}_{pe}$ is the electron inertial length) and zero guide field. For finite guide field or thicker current sheets, the fastest growing mode is a non-tearing type. However, growth rates of the fastest 2-D tearing and 3-D non-tearing modes are comparable for thin current sheets ( $d_{e} Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815001257 • ##### Article: Behaviour of runaway electrons in the HL-2A plasmas with LHCD and ECCD [Hide abstract] ABSTRACT: The behaviour of runaway electrons have been investigated in lower hybrid current drive (LHCD) and electron cyclotron current drive (ECCD) plasmas as well as the LHCD only plasmas in the HL-2A tokamak. The fast electrons generated by lower hybrid waves (LHWs) and electron cyclotron waves (ECWs) can act as a seed population for runaway electrons. In the LHCD only discharges, a large number of runaway electrons are produced after the termination of lower hybrid (LH) power by conversion of fast electrons into runaway electrons due to the fast electron tail which extends above the runaway critical energy. However, in contrast to LHCD only discharges, during the simultaneous application of LHCD and ECCD discharges, runaway electrons cannot be created by the termination of LH power when the ECCD is on duty. The runaway production is observed to be enhanced until the EC power termination. The loop voltage increase due to the termination of EC power gives rise to a decline in the critical runaway energy, which leads to some of the energetic fast electrons converting into runaway electrons via the acceleration from the toroidal electric field. That is, the fast electrons created by waves can be accelerated into the runaway regime due to the Dreicer process. Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S002237781500118X • ##### Article: The stochastic tetrad magneto-hydrodynamics via functional formalism [Hide abstract] ABSTRACT: In this work we discuss an application of the Tetrad Dynamics approach, a stochastic dynamical theory already introduced in hydrodynamic turbulence, to incompressible magneto-hydrodynamics. This theoretical framework is capable of taking into account some crucial aspects of turbulent plasmas, namely, (i) its material nature, which is stressed through the adoption of Lagrangian variables, (ii) its probabilistic dynamics, which is fundamental to understand the intermittency and highly irregular nature of turbulence, and (iii) the multi-scale character of interactions, which is approached by promoting the space size of parcels to the role of a dynamical variable. In particular, here, we construct the probabilistic equations of motion for quantities describing the evolution of a turbulent plasma (a matrix${\bf\varrho}$describing the parcel’s shape, the plasma velocity and magnetic field coarse-grained gradient tensors,$\unicode[STIX]{x1D648}$and$\unicode[STIX]{x1D652}$), resorting the functional formalism of classical statistical dynamics. Through the introduction of a stochastic action and using a path integral approach, the statistical properties of$({\bf\varrho},\unicode[STIX]{x1D648},\unicode[STIX]{x1D652})$can be derived from those of noises appearing in their equations of motion, both at equilibrium and out of equilibrium. Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815001105 • ##### Article: Collisionless relaxation of non-gyrotropic downstream ion distributions: dependence on shock parameters [Hide abstract] ABSTRACT: Upon crossing the shock front, ions begin to gyrate. The ion distribution just behind the ramp is manifestly non-gyrotropic. The gyration of the ion distribution as a whole results in spatially periodic oscillations of the ion pressure. The magnetic pressure must oscillate in the opposite phase to ensure the maintenance of the pressure balance throughout the shock front. The ion non-gyrotropy and the pressure oscillations gradually damp due to the collisionless gyrophase mixing. The rate of this relaxation depends on the basic shock parameters. The most influential are the angle between the shock normal and the magnetic field, the upstream ion temperature and the magnetic compression. Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815001154 • ##### Article: A tutorial introduction to the statistical theory of turbulent plasmas, a half-century after Kadomtsev’s Plasma Turbulence and the resonance-broadening theory of Dupree and Weinstock [Hide abstract] ABSTRACT: In honour of the 50th anniversary of the influential review/monograph on plasma turbulence by B. B. Kadomtsev as well as the seminal works of T. H. Dupree and J. Weinstock on resonance-broadening theory, an introductory tutorial is given about some highlights of the statistical–dynamical description of turbulent plasmas and fluids, including the ideas of nonlinear incoherent noise, coherent damping, and self-consistent dielectric response. The statistical closure problem is introduced. Incoherent noise and coherent damping are illustrated with a solvable model of passive advection. Self-consistency introduces turbulent polarization effects that are described by the dielectric function${\mathcal{D}}$. Dupree’s method of using${\mathcal{D}}$to estimate the saturation level of turbulence is described; then it is explained why a more complete theory that includes nonlinear noise is required. The general theory is best formulated in terms of Dyson equations for the covariance$C$and an infinitesimal response function$R$, which subsumes${\mathcal{D}}$. An important example is the direct-interaction approximation (DIA). It is shown how to use Novikov’s theorem to develop an$\boldsymbol{x}$-space approach to the DIA that is complementary to the original$\boldsymbol{k}$-space approach of Kraichnan. A dielectric function is defined for arbitrary quadratically nonlinear systems, including the Navier–Stokes equation, and an algorithm for determining the form of${\mathcal{D}}$in the DIA is sketched. The independent insights of Kadomtsev and Kraichnan about the problem of the DIA with random Galilean invariance are described. The mixing-length formula for drift-wave saturation is discussed in the context of closures that include nonlinear noise (shielded by${\mathcal{D}}$). The role of$R$in the calculation of the symmetry-breaking (zonostrophic) instability of homogeneous turbulence to the generation of inhomogeneous mean flows is addressed. The second-order cumulant expansion and the stochastic structural stability theory are also discussed in that context. Various historical research threads are mentioned and representative entry points to the literature are given. Some outstanding conceptual issues are enumerated. Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815000756 • ##### Article: Integrodifferential models of electron transport for negative ion sources [Hide abstract] ABSTRACT: Thanks to the presence of a transverse magnetic flux density ($B_{x}$and$B_{y}$where$z$is the extraction axis), the undesired extraction of electrons from a negative ion source is reduced and it is due to collisions. The electron transport is studied with a kinetic model, including Vlasov–Poisson effects and atomic collisions. The integrodifferential equations (IDE) resulting from a reduction to a one-dimensional problem (1-D) by integration on characteristic orbits are strongly affected by the trapped orbits, as here evaluated; a kernel calculation with a partial wave approximation is introduced. Dependencies from the local drift velocity$v_{d}$and effective Larmor radius$L_{e}$are found. Solutions are investigated in simple cases with a constant electron current (no additional electron production). Equilibrium solution and electron conductivity are analytically obtained. Presheath solutions are discussed; the approximated conversion to differential equations that are adequate for presheath only (with moderated electric field gradient$E_{z,z}>-eB_{x}^{2}/m$) and their numeric solutions coupled to Poisson equation are reported, and compared to iterative IDE solutions. Examples with different values of$L_{e}\$ and mean free path (mfp) ratio are described.
Journal of Plasma Physics 12/2015; 81(06). DOI:10.1017/S0022377815001130
• ##### Article: Effect of the laser intensity profile on the shock non-uniformity in a directly driven spherical target
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ABSTRACT: An axially symmetric laser beam configuration irradiating a spherical capsule has been considered in the context of inertial confinement fusion (ICF). The laser beams are located at co-latitudes 49° and 131° and mimic the quad positions in the second cone of the Laser Mégajoule Facility. The capsule is directly irradiated by the laser beams whose energy deposition generates a nearly spherical shock wave. Two-dimensional hydrodynamic numerical simulations have been performed to analyse the non-uniformity of the shock wavefront launched inward throughout the target. Different laser intensity profiles, calculated by the illumination model, have been tested. The performance, in terms of shock non-uniformity, has been compared, and it is found that with an appropriate choice of the laser intensity profile it is possible to control the shock non-uniformity at early times.
Journal of Plasma Physics 10/2015; 81(05). DOI:10.1017/S0022377815000938
• ##### Article: Monte Carlo particle-in-cell methods for the simulation of the Vlasov–Maxwell gyrokinetic equations
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ABSTRACT: The particle-in-cell (PIC) algorithm is the most popular method for the discretisation of the general 6D Vlasov–Maxwell problem and it is widely used also for the simulation of the 5D gyrokinetic equations. The method consists of coupling a particle-based algorithm for the Vlasov equation with a grid-based method for the computation of the self-consistent electromagnetic fields. In this review we derive a Monte Carlo PIC finite-element model starting from a gyrokinetic discrete Lagrangian. The variations of the Lagrangian are used to obtain the time-continuous equations of motion for the particles and the finite-element approximation of the field equations. The Noether theorem for the semi-discretised system implies a certain number of conservation properties for the final set of equations. Moreover, the PIC method can be interpreted as a probabilistic Monte Carlo like method, consisting of calculating integrals of the continuous distribution function using a finite set of discrete markers. The nonlinear interactions along with numerical errors introduce random effects after some time. Therefore, the same tools for error analysis and error reduction used in Monte Carlo numerical methods can be applied to PIC simulations.
Journal of Plasma Physics 10/2015; 81(05). DOI:10.1017/S0022377815000574
• ##### Article: Complex astrophysical experiments relating to jets, solar loops, and water ice dusty plasma
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ABSTRACT: Recent results of three astrophysically relevant experiments at Caltech are summarized. In the first experiment magnetohydrodynamically driven plasma jets simulate astrophysical jets that undergo a kink instability. Lateral acceleration of the kinking jet spawns a Rayleigh–Taylor instability, which in turn spawns a magnetic reconnection. Particle heating and a burst of waves are observed in association with the reconnection. The second experiment uses a slightly different setup to produce an expanding arched plasma loop which is similar to a solar corona loop. It is shown that the plasma in this loop results from jets originating from the electrodes. The possibility of a transition from slow to fast expansion as a result of the expanding loop breaking free of an externally imposed strapping magnetic field is investigated. The third and completely different experiment creates a weakly ionized plasma with liquid nitrogen cooled electrodes. Water vapour injected into this plasma forms water ice grains that in general are ellipsoidal and not spheroidal. The water ice grains can become quite long (up to several hundred microns) and self-organize so that they are evenly spaced and vertically aligned.
Journal of Plasma Physics 10/2015; 81(05). DOI:10.1017/S0022377815000604
• ##### Article: Comparative study of electron motion and stability for different focusing regimes in a free-electron laser with three-dimensional helical wiggler
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ABSTRACT: Since the electromagnetic energy gained by the laser wave in a free-electron laser (FEL) is transferred from the kinetic energy loss of a relativistic electron beam, the stability of electron motion is one of the key factors that affect FEL performance. In this paper the stability of electron motion is compared for different focusing regimes. It is demonstrated that the natural focusing regime of a three-dimensional wiggler is easily broken by the self-field of the electron beam. The magnetic focusing regime of an axial guide magnetic field is based on the superposition of a strong Larmor rotation on the transverse quiver motion of the electrons, while the electric focusing regime of an ion-channel guiding field generates an electric force to counteract the divergent effect of the beam self-field. In comparison with the magnetic focusing regime of an external magnetic system, the electric focusing regime of an ion-channel guiding field may yield smaller instantaneous Larmor radius and slighter Larmor-centre deviation from the axis and provide better motion stability.
Journal of Plasma Physics 10/2015; 81(05). DOI:10.1017/S0022377815000653
• ##### Article: Resonant interaction between laser and electrons undergoing betatron oscillations in the bubble regime
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ABSTRACT: The betatron radiation in the bubble regime is studied in the presence of resonant interaction between the accelerated electrons and the driver laser pulse tail. The calculations refer to experimental parameters available at the FLAME laser facility at the National Laboratories of Frascati (LNF), and represent the radiation spectra and spatial distributions to be expected in forthcoming experiments.
Journal of Plasma Physics 10/2015; 81(05). DOI:10.1017/S0022377815000926