15 research outputs found
Effect of temperature anisotropy on various modes and instabilities for a magnetized non-relativistic bi-Maxwellian plasma
Using kinetic theory for homogeneous collisionless magnetized plasmas, we
present an extended review of the plasma waves and instabilities and discuss
the anisotropic response of generalized relativistic dielectric tensor and
Onsager symmetry properties for arbitrary distribution functions. In general,
we observe that for such plasmas only those electromagnetic modes whose
magnetic field perturbations are perpendicular to the ambient magneticeld,
i.e.,B1 \perp B0, are effected by the anisotropy. However, in oblique
propagation all modes do show such anisotropic effects. Considering the
non-relativistic bi-Maxwellian distribution and studying the relevant
components of the general dielectric tensor under appropriate conditions, we
derive the dispersion relations for various modes and instabilities. We show
that only the electromagnetic R- and L- waves, those derived from them and the
O-mode are affected by thermal anisotropies, since they satisfy the required
condition B1\perpB0. By contrast, the perpendicularly propagating X-mode and
the modes derived from it (the pure transverse X-mode and Bernstein mode) show
no such effect. In general, we note that the thermal anisotropy modifies the
parallel propagating modes via the parallel acoustic effect, while it modifies
the perpendicular propagating modes via the Larmor-radius effect. In oblique
propagation for kinetic Alfven waves, the thermal anisotropy affects the
kinetic regime more than it affects the inertial regime. The generalized fast
mode exhibits two distinct acoustic effects, one in the direction parallel to
the ambient magnetic field and the other in the direction perpendicular to it.
In the fast-mode instability, the magneto-sonic wave causes suppression of the
firehose instability. We discuss all these propagation characteristics and
present graphic illustrations
Kinetic description of intense beam propagation through a periodic focusing field for uniform phase-space density
Laser-induced fluorescence diagnostic of barium ion plasmas in the Paul trap simulator experiment
The Paul Trap Simulator Experiment (PTSX) is a cylindrical Paul trap whose purpose is to simulate the nonlinear dynamics of intense charged particle beam propagation in alternating-gradient magnetic transport systems. To investigate the ion plasma microstate in PTSX, including the ion density profile and the ion velocity distribution function, a laser-induced fluorescence diagnostic system is being developed as a nondestructive diagnostic. Instead of cesium, which has been used in the initial phase of the PTSX experiment, barium has been selected as the preferred ion for the laser-induced fluorescence diagnostic. A feasibility study of the laser-induced fluorescence diagnostic using barium ions is presented with the characterization of a tunable dye laser. The installation of the barium ion source and the development of the laser-induced fluorescence diagnostic system are also discussed. (c) 2005 Elsevier B.V. All rights reservedclose2
Simulation of long-distance beam propagation in the Paul trap simulator experiment
The Paul Trap Simulator Experiment (PTSX) simulates the propagation of intense charged particle beams over distances of many kilometers through magnetic alternating-gradient (AG) transport systems by making use of the similarity between the transverse dynamics of particles in the two systems. One-component pure ion plasmas have been trapped that correspond to normalized intensity parameter s = omega(p)(2)(0)/2 omega(q)(2)<= 0.8 where omega(p)(r) is the plasma frequency and omega(q) is the average transverse focusing frequency in the smooth focusing approximation. The PTSX device confines one-component cesium ion plasmas for hundreds of milliseconds, which is equivalent to beam propagation over 10 km. Results are presented for experiments in which the amplitude of the confining voltage waveform has been modified as a function of time. Recent modifications to the device are described, and both the change from a cesium ion source to a barium ion source, and the development of a laser-induced fluorescence diagnostic system are discussed. (c) 2005 Elsevier B.V. All rights reservedclose111
Low-temperature catalytic decomposition of hydrogen sulfide on metal catalysts under layer of solvent
Chemical industry: Servitization in niches
The chemical industry represents an important share of global manufacturing and all other manufacturing sectors employ products made by the chemical industry. Its strong B2B focus makes the chemical industry an interesting subject for analysis of the state-of-the-art servitization in this industry. Even more interest in the chemical industry's servitization arises from the fact that United Nations Industrial Development Organization (UNIDO) is strongly promoting the service of "chemical leasing" because of its potential to reduce the environmental impact of the use of chemicals. Thus, this paper presents a state-of-the-art analysis of servitization in chemical industry. A review of the case study literature shows that chemical management services appeal only to a sub-group of chemicals, namely specialty chemicals. As a result, commonalities and differences between certain types of specialty chemicals and their service offer implications are highlighted. We categorise the providers and customers of chemical management services and conclude by evaluating the servitization potential of the chemical industry. The empirical basis of this research comes from the literature, case studies and firm documents
Laser time-dependent electric field on the electromagnetic instability with Coulomb collisions
Vacuum laser acceleration of relativistic electrons using plasma mirror injectors
International audienceAccelerating particles to relativistic energies over very short distances using lasers has been a long-standing goal in physics. Among the various schemes proposed for electrons, vacuum laser acceleration has attracted considerable interest and has been extensively studied theoretically because of its appealing simplicity: electrons interact with an intense laser field in vacuum and can be continuously accelerated, provided they remain at a given phase of the field until they escape the laser beam. But demonstrating this effect experimentally has proved extremely challenging, as it imposes stringent requirements on the conditions of injection of electrons in the laser field. Here, we solve this long-standing experimental problem by using a plasma mirror to inject electrons in an ultraintense laser field, and obtain clear evidence of vacuum laser acceleration. With the advent of petawatt lasers, this scheme could provide a competitive source of very high charge (nC) and ultrashort relativistic electron beams