Despite the heroic efforts for which i am very grateful to translate my handwritten materials into latex, and extensive editing on my part, i dont doubt that there are many typographical errors. Summary of ucrl protron mirror machine program by r. Evaluation of two directcurrent methods of plasma production for use in magnetic mirror experiments by roman krawec, george m. Massachusetts institute of technology introduction to plasma. Magnetic mirror traps the particles so they can be heated to 10 million kelvins. A magnetic field is usually described as a distribution of nearly parallel nonintersecting field lines. Plasma in magnetic bottle principle of magnetic bottle. The magnetic compression ratio of the plasma stream varied from 5 to 60 at the initial diameter of 5 cm. The point where the angle reaches 90o is called the mirror point. A magnetic bottle is two magnetic mirrors placed close together. Owing to the presence of free ions, using plasma for ion sources is quite. Swett lewis research center an experimental investigation of two methods for producing a hydrogen plasma was conducted. Paper signatures of ring currents in a magnetic mirror plasma.
Modeling of high density and strong magnetic field. Magnetic fields and magnetic diagnostics for tokamak plasmas. The variable specific impulse magnetoplasma rocket vasimr is an electrothermal thruster under development for possible use in spacecraft propulsion. Although mirror machines showed a remarkable resistance to macroscopic plasma instabilities they were prone to develop microscopic instabilities.
Magnetic mirror, static magnetic field that, within a localized region, has a shape such that approaching charged particles are repelled back along their path of approach. Degroot department of applied science, university of california, davis, ca 95616, usa received 1 july 1981 a. Magnetic mirror definition is a magnetic field that confines a plasma by reflecting ions back toward the main plasma concentration. Plasma cleaning of iter first mirrors in magnetic field. Introduction magnetic mirror fusionl was the subject of intense research in the early 1960s. Pdf electrons in magnetic mirror geometry researchgate. Dec 23, 2015 28b magnetic mirrors introduction to plasma physics by j d callen lucius fox. Plasma heating by antiproton annihilation in magnetic. Jun 22, 2015 science magnetic mirror holds promise for fusion in a polywell design, a highdensity plasma excludes magnetic field, traps itself. Science magnetic mirror holds promise for fusion in a polywell design, a highdensity plasma excludes magnetic field, traps itself. For the parameters chosen, the main plasma current was injected in the form of two bursts with velocities of 107 and 2105 cmsec, in passing through the first magnetic mirror, both bursts were broken up into. These are transcriptions of the notes from which i teach the single semester course introduction to plasma physics. The figure shows field lines in a cylindrically symmetric magnetic mirror plasma confinement device.
Plasma from ancient greek, meaning moldable substance is one of the four fundamental states of matter, and was first described by chemist irving langmuir in the 1920s. Transportation of cold plasma jet in multiplemirror. Magnetic mirror a magnetic mirror is a configuration of magnetic field lines in which a charged particle is reflected from a high density magnetic field to low density magnetic field. It consists of two ring electromagnets that set up a bulging magnetic. We investigate the heating of a plasma by an electron beam in an adiabatic trap with mirror ratio r 5. Lecture 15 magnetohydrodynamics, beta, magnetic pressure, sausage instabilities, kink instability duration. Comparison of low and high plasma con nement in a magnetic cusp con. A 98 mm diameter mirror with deposits has been cleaned using rf ar plasma without magnetic field and a bias up to 350 v. They are for private circulation only and are not to be further transmitted without consent of the authors and major professor. The magnetic mirror principle is an old one in the realm of charged particle dynamics. Degroot department of applied science, university of california, davis, ca 95616, usa. Mirror machine department of nuclear sciences and applications. Interest in research on plasma liner driven magnetoinertial fusion has recently been stimulated by a plasma jet driven magnetic flux compression experiments, b the progress of high.
Mirror ratios range from values of order 2 to 10 or more for typical magnetic mirrors fig. Plasma exists in many forms in nature and has a widespread use in science and technology. Being a polycrystalline mo mirror, the diffuse reflectivity increased drastically under the ion bombardment, highlighting the need for single or nanocrystalline materials for iters fms. The original idea was based on the fact that an electric current generates a magnetic field, and that the currents flowing in the plasma will pinch the plasma, containing it within its own magnetic field. Magnet plus magnetic mirror check your appearance or see whos behind you.
Ion current densities up to 12 macm 2, plasma densities about 1011 cm 3 and electron temperatures about 25 ev were measured by a langmuir probe. The 312 x 2 oblong mirror provides crystal clear reflections and is adjustable via two universal joints to provide an optimal viewing angle. One could build plasma motors, which differ from ordina ry motors by. Plasma guns could be used in ion rocket engines, as an example. Studies of cryogenic electron plasmas in magnetic mirror fields. High energy electron con nement in a magnetic cusp con. Jan 29, 2016 magnetic mirror a magnetic mirror is a configuration of magnetic field lines in which a charged particle is reflected from a high density magnetic field to low density magnetic field. The plasma state can be contrasted with the other states. The charged particles are produced by ionization of a propellant gas, which creates both ions and electrons and forms what is called a plasma. For example, two parallel coils separated by a small distance, carrying the same current in the same direction will produce a magnetic bottle between them. This probably means that there is a mirror ratio limit beyond which the. In section 2 we introduce ey plasma properties like quasik neutrality, shielding, particle transport processes and sheath formation. Magnetic mirror holds promise for fusion ars technica. Plasma is a state of matter in which an ionized gaseous substance becomes highly electrically conductive to the point that longrange electric and magnetic fields dominate the behaviour of the matter.
Plasma potential in a magnetic mirror sprotts gateway. Officemate magnetplus magnetic mirror, white 92542 by officemate. The plasma pump a new magnetic mirror plasma confinement. The preferred embodiments described herein present a new technique to confine electrons 3 to produce a low pressure, dense plasma directly on a substrate. A magnetic multi mirror machine is been developed for plasma production with electron cyclotron resonance ecr in the uhf frequency range and low rf power. A multi magnetic mirror machine for plasma production with electron. Modeling of high density and strong magnetic field generation. A plasma confinement apparatus, wherein multiple magnetic mirror cells are linked by magnetic field lines inside of a solenoid with the mirroring regions for adjacent magnetic mirror cells each formed by a separate mirror coil inside of the solenoid. This chapter contains a short discussion of some fundamental plasma phenomena.
Fundamentals of plasma physics and controlled fusion. Express 1 045006 view the article online for updates and enhancements. The result is a novel plasma source that has unique and important advantages enabling advancements in pecvd, etching, and plasma treatment processes. Plasma heating by antiproton annihilation in magnetic mirror. Electron cyclotron resonance plasma enhanced direct current. Clearly, such instabilities are likely to have a disastrous effect on plasma confinement in a mirror machine. Plasmainmagneticbottle principle of magnetic bottle.
Signatures of ring currents in a magnetic mirror plasma. Pdf investigation of plasma immersion ion implantation. In this note we shall consider the latter case to see how the magnetic mirror effect can reduce the rate of particle loss. Magnetic fields and magnetic diagnostics for tokamak.
For these reasons, magnetic mirror machines are not particularly successful plasma confinement devices, and attempts to achieve nuclear fusion using this type of device have mostly been abandoned. This was written based on lecture notes for a graduate course and an advanced undergraduate course those have been. The mirror was one of the earliest major approaches to fusion power, along with the stellarator and zpinch machines. Since the fusion power output scales as 2 for a given magnetic eld, high operation is advantageous for a compact economical fusion reactor. Mhd stability and confinement of plasmas in a single mirror cell. Mirror, firehose and cosmicraydriven instabilities in a. Passage of a plasma burst through a magnetic mirror. Magnetic mirror let us follow the guiding center of a particle moving along an inhomogeneous magnetic field by considering the magnetic moment. A multi magnetic mirror machine for plasma production with. Seen in planetary magnetospheres, magnetic bottles, coronal. Modeling of high density and strong magnetic field generation by plasma jet compression s. It consists of a gas of ions atoms which have some of their orbital electrons removed and free electrons. The plasma generating hot cathode filament is placed within the mirror so that the primary electrons generated with energies 75 ev are confined by the magnetic mirror effect resulting in a combination of a rapid bounce motion with a slower azimuthal drift whose direction is determined by the orientation of the magnet stacks.
Plasma confinement in a mirror magnetic field was applied to the electron cyclotron resonance ecr plasma enhanced dc sputtering discharge sustained at pressures below 10. Magnetic fields and tokamak plasmas alan wootton 5 introduction this series of notes tries to lay the foundations for the interpretation of magnetic fields and fluxes, often in terms of equilibrium plasma parameters. Pdf plasma cleaning of iter first mirrors in magnetic. Plasma research express paper signatures of ring currents in a magnetic mirror plasma experiment to cite this article. Ion acceleration in plasmas emerging from a heliconheated. Product description check your appearance or see whos behind you. A magnetic mirror, known as a magnetic trap in russia and briefly as a pyrotron in the us, is a type of magnetic confinement device used in fusion power to trap high temperature plasma using magnetic fields.
The plasma pump a new magnetic mirror plasma confinement scheme. Theory predicted that a multiplemirror magnetic field should not significantly decelerate and weaken collisional. The machine is mainly designed to be used for investigation of basic magnetized plasma phenomena. Post under the sponsorship of the atomic energy commission, work has been going forward at the university of california radiation laboratory since 1952 to investigate the application of the socalled magnetic mirror effect to the creation and confinement of a high temperature plasma. Us4166760a plasma confinement apparatus using solenoidal. Variable specific impulse magnetoplasma rocket wikipedia. Magnetic mirror, static magnetic field that, within a localized region, has a shape such that approaching charged particles are repelled back along their path of approach a magnetic field is usually described as a distribution of nearly parallel nonintersecting field lines.
These basic features of plasmas could be used to build plasma guns that eject ions at velocities up to 100 kmsec. A study has been made of the behavior of plasma bursts as they move along the axes of an ogrenok magnetic mirror machine, the bnrsts were accelerated by a coaxial ptasma injector. Transportation of cold plasma jet in multiplemirror magnetic. Massachusetts institute of technology introduction to. An early study of qmachine cesium plasmas expanding along a magnetic. Magnetic mirror definition of magnetic mirror by merriam. Cassenti united technologies research center east hartford, ct terry kammash university of michigan ann arbor, mi abstract magnetic mirror fusion propulsion shows promise as a means for opening up interplanetary travel. Lecture notes introduction to plasma physics i nuclear. Extrastrong magnetic backing keeps accessories firmly in place on most metal surfaces. Plasma heating by antiproton annihilation in magnetic mirror fusion propulsion b. The preferred embodiments described herein provide a magnetic mirror plasma source.
For these reasons, magnetic mirror machines are not particularly successful plasma confinement devices, and attempts to achieve nuclear fusion using this. Notes on the magnetic mirror effect oxford academic journals. The direction of these lines determines the direction of the magnetic field, and the density closeness of the lines. The general tools and instruments mb560 312 x 2 inspection mirror with magnetic base is frequently used by machinists to observe the backside of a work piece while it is being milled, tooled or drilled. Investigation of plasma immersion ion implantation process in magnetic mirror geometry article pdf available in ieee transactions on plasma science 3911. Pdf landaus theory of electron motion in stationary magnetic fields is extended to the. Electron cyclotron resonance plasma enhanced direct. Lectures in plasma physics office of technology services. The mirror was one of the earliest major approaches to fusion power, along with the stellarator and z. Plasma can be artificially generated by heating a neutral gas or subjecting it to a strong. Volume 86a, number 3 physics letfers 9 november 1981 the plasma pump a new magnetic mirror plasma confinement scheme m. In this work we have investigated the electromagnetic drift instability on the basis of the model 7, 8 recently developed specifically for.
Paper signatures of ring currents in a magnetic mirror. It is a plasma propulsion engine, one of several types of spacecraft electric propulsion systems. Hayes department ofapplied science, university of california, davis, ca 95616, usa and lawrence livermore national laboratory, livermore, ca 94550, usa and j. In order to prevent mhd flute instabilities from disrupting the plasma in the gasdymamc mirror, them must be sufficient plasma in the regions ofgood magnetic field curvature to offset the negative effects of the plasma in the regions ofbad magnetic field eurvatme. Pdf plasma cleaning of iter first mirrors in magnetic field.
While the traditional magneticelectrostatic confinement method is ideal for many applications, some processes are not best served with this arrangement. Sprott september 1972 plasma studies university of wisconsin plp 484 these plp reports are informal and preliminary and as such may contain errors not yet eliminated. The plasmagenerating hot cathode filament is placed within the mirror so that the primary electrons generated with energies 75 ev are confined by the magnetic mirror effect resulting in a combination of a rapid bounce motion with a slower azimuthal drift whose direction is determined by the orientation of the magnet stacks. Mnras mirror, firehose and cosmicraydriven instabilities in a high. Studies of cryogenic electron plasmas in magnetic mirror. It uses radio waves to ionize and heat an inert propellant, then a magnetic field to accelerate the resulting plasma, generating thrust. Plasma magnetic confinement with mirror type fields has been used to investigate fusion 1 and space plasma 2 phenomena for many years. Ion current densities up to 12 macm 2, plasma densities about 10 11 cm. Magnetic fusion science addresses many interrelated issues equilibrium.
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