8 research outputs found
Stability Dust-Ion-Acoustic Wave in Dusty Plasmas With Stream -Influence of Charge Fluctuation of Dust Grains
There is a quickly increasing wealth of experimental data on so-called dusty
plasmas i. e. ionized gases or usual plasmas that contain micron sized charged
particles. Interest in these structures is driven both by their importance in
many astrophysical as well as commercial situations. Among them are linear and
nonlinear wave phenomena. We consider the influence of dust charge fluctuations
on stability of the ion-acoustic waves when the stream of particles is present.
It is assumed that all grains of dust have equal masses but charges are not
constant in time-they may fluctuate in time. The dust charges are not really
independent of the variations of the plasma potentials. All modes will
influence the charging mechanism, and feedback will lead to several new
interesting and unexpected phenomena. The charging of the grains depends on
local plasma characteristics. If the waves disturb these characteristic, then
charging of the grains is affected and the grain charge is modified, with a
resulting feedback on the wave mode. In case considering here, when temperature
of electrons is much greater then the temperature of the ions and temperature
of electrons is not great enough for further ionization of the ions, we show
that stability of the acoustic wave depends only one phenomenological
coefficient.Comment: 4 pages,Plasma 2005,Opole-Turawa, Poland, 6-9 september 200
Wave Propagation and Diffusive Transition of Oscillations in Pair Plasmas with Dust Impurities
In view of applications to electron-positron pair-plasmas and fullerene
pair-ion-plasmas containing charged dust impurities a thorough discussion is
given of three-component Plasmas. Space-time responses of multi-component
linearized Vlasov plasmas on the basis of multiple integral equations are
invoked. An initial-value problem for Vlasov-Poisson -Ampere equations is
reduced to the one multiple integral equation and the solution is expressed in
terms of forcing function and its space-time convolution with the resolvent
kernel. The forcing function is responsible for the initial disturbance and the
resolvent is responsible for the equilibrium velocity distributions of plasma
species. By use of resolvent equations, time-reversibility, space-reflexivity
and the other symmetries are revealed. The symmetries carry on physical
properties of Vlasov pair plasmas, e.g., conservation laws. Properly choosing
equilibrium distributions for dusty pair plasmas, we can reduce the resolvent
equation to: (i) the undamped dispersive wave equations, (ii) wave-diffusive
transport equation (iii) and diffusive transport equations of oscillations. In
the last case we have to do with anomalous diffusion employing fractional
derivatives in time and space. Fractional diffusion equations account for
typical anomalous features, which are observed in many systems, e.g. in the
case of dispersive transport in amorphous semiconductors, liquid crystals,
polymers, proteins and biosystems.Comment: 6 page
The Comet Interceptor Mission
Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESA's F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum ÎV capability of 600Â ms-1. Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000Â km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes - B1, provided by the Japanese space agency, JAXA, and B2 - that will follow different trajectories through the coma. While the main probe passes at a nominal 1000Â km distance, probes B1 and B2 will follow different chords through the coma at distances of 850Â km and 400Â km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the mission's science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule
The Comet Interceptor Mission
Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESAâs F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum ÎV capability of 600 msâ1. Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000 km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes â B1, provided by the Japanese space agency, JAXA, and B2 â that will follow different trajectories through the coma. While the main probe passes at a nominal 1000 km distance, probes B1 and B2 will follow different chords through the coma at distances of 850 km and 400 km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the missionâs science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule