US3755073A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hybrid laser plasma target - neutral beam injection fusion system
Assignee: United States Atomic Energy Commission
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Filing: 1971-06-21
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Granted: 1973-08-28
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Expires: 1991-06-21
Abstract
Abstract This invention relates to a method for creating a high density plasma by heating in a vacuum a pellet located within a magnetic field to produce a dense, magnetically confined, relatively warm plasma of ions and electrons, and injecting thereinto an energetic neutral beam to form a high temperature, stable, magnetically confined, steady-state plasma.
Inventors
- 👤 J Woo
- 👤 W Fader
- 👤 A Haught
- 👤 D Polk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:58
CPC Classifications
H; H05; H05H; H05H1/00; H05H1/02; H05H1/22; Y; Y02; Y02E; Y02E30/00; Y02E30/10
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
288 words
Method for sequentially creating a plasma in a vacuum system having a neutral beam injection source of 0.1 amp, 10 ke V, neutral, atomic hydrogen particles of average energy of 0.5 ke V per particle in a beam, comprising the steps of: a. producing a rapidly expanding localized ball of plasma within an open-ended baseball seam shaped winding for producing a constant, open-ended minimum-B, mirror, vacuum magnetic field within the vacuum system by directing Q-switched, lens focused, laser light beam in a first direction into an open end of the constant, open-ended, minimum B, mirror, vacuum magnetic field and against a solid 50 Mu diameter particle of lithium deuteride that is electrically suspended therein, so as to form the expanding localized ball of plasma by vaporization, ionization and collisional heating of the solid 50 Mu diameter particle of lithium deuteride that is electrically suspended within the vacuum system; b. capturing the expanding ball of plasma for confining the plasma as it expands within the vacuum magnetic field and, upon permeation of the plasma by the magnetic field, confining the plasma within the vacuum magnetic field at a particle number density of greater than 1012cm 3, said vacuum magnetic field and confined plasma being adapted to receive the neutral beam of neutral hydrogen particles; and c. injecting the 0.1 amp, 10 ke V neutral hydrogen beam having an average energy of 0.5 ke V per particle into the plasma so confined to ionize the injected neutral beam and to heat the confined plasma so as to sustain it against decay, while producing particles. emenating from the confined plasma and pumping them so as to prevent a high density background ambient gas that would contaminate and degrade the confined plasma.
Claim 2
Dependent Claim
64 words
The method of claim 2 wherein the heating of the solid particle of lithium deuteride is produced first by the laser light beam, and ionization of the injected beam is effected after the step of capturing the expanding localized ball of plasma so as to achieve a steady state confined plasma at a density of at least 1012 cm 3 in about 0.5 seconds.
Claim 3
Dependent Claim
93 words
The method of claim 2 wherein the expanding ball of plasma has a directed expansion energy produced by the step of laser light heating a solid particle of lithium deuteride having a number density of about 1016 lithium and hydrogen particles in the vacuum magnetic field, wherein the step of magnetically confining the expanding plasma effects the stable randomization of the confined plasma produced by the laser light heating of the solid particle of lithium deuteride and the confining of the expanding ball of plasma that results therefrom in the vacuum magnetic field.
Claim 4
Dependent Claim
52 words
The method of claim 1 wherein said injection step injects the neutral beam of neutral hydrogen particles so that said injection maintains the number density of the magnetically confined ball of plasma against decay between about 5 X 9 1015 particles per cubic centimeter and 1 X 1012 particles per cubic centimeter.
Claim 5
Dependent Claim
160 words
The method of claim 1 wherein the step of magnetically confining the expanding ball of plasma, comprises engergizing the open ended, minimum-B mirror, vacuum magnetic field with a predetermined capture volume around the position of the solid pellet of lithium deuteride for continuously receiving the neutral beam of neutral hydrogen particles after the laser beam generates the expanding ball of plasma by vaporization ionization and collisional heating of the solid particle constituents so that the laser produced expanding ball of plasma initially expands with a directed velocity relative to the pellet position in the predetermined capture volume around the solid pallet during the radiatiOn thereof by the laser light beam, and maintaining the vacuum magnetic field while the ball of plasma expands therein so that at least a portion of the directed velocity of the expanding ball of plasma is stopped within the capture volume by the vacuum magnetic field for receiving the neutral beam of neutral hydrogen particles therein.
Claim 6
Dependent Claim
60 words
The method of claim 6 wherein the vacuum magnetic field is maintained constant in time at a strength sufficient to capture at least a portion of the expanding ball of plasma at a ratio Beta of energy density of the laser produced plasma to that of the vacuum magnetic field so that the plasma is captured at Beta 22 1.
Claim 7
Dependent Claim
84 words
The method of claim 2 wherein the laser light heating of the solid particle of lithium deuteride causes the ball of plasma to expand with a Maxwellian velocity distribution function, and the step of magnetically capturing the expanding ball of plasma effects the randomizing of the expanding ball of plasma by the capture thereof within a magnetic capture volume formed by the vacuum magnetic field so that randomized Maxwellian velocity distribution results and contributes to the stable capture of the expanding ball of plasma.
Claim 8
Dependent Claim
98 words
The method of claim 2 wherein said expanding ball of plasma is captured by the step of producing the vacuum magnetic field at a strength around the solid particle of lithium deuteride during the laser light heating thereof sufficient so that the expanding ball of plasma is permeated by the vacuum magnetic field and the expanding ball of plasma is captured at a ratio Beta of the energy density of the plasma to that of the vacuum magnetic field of Beta < 1 and at a density upon capture of greater than 1 X 0 1012 cm 3.
Claim 9
Dependent Claim
48 words
The method of claim 9 wherein said plasma is used as a target for said neutral beam after said plasma is permeated by said magnetic field to produce said plasma at Beta < 1 and at a density upon said confinement greater than 1 X 1012 cm 3
Claim 10
Dependent Claim
27 words
The method of claim 10 wherein the neutral beam heats the plasma by charge exchange collisons to a temperature determined by the energy of the neutral beam.
Claim 11
Dependent Claim
28 words
The method of claim 11 wherein said change exchange collisions replace the constituent ions of the plasma with ionized atoms from the neutral beam during the injecting step.
Claim 12
Dependent Claim
65 words
The method of claim 2 wherein the injecting step injects a beam of atoms into the confined plasma with a velocity distribution function for effecting the ionization of the beam atoms in the confined plasma while the confined plasma is sufficiently collisional that said velocity distribution function is thermalized over the plasma velocity distribution function, thereby to inhibit the development of destructiveinstabilities in said plasma.
Claim 13
Dependent Claim
63 words
The method of claim 1 wherein said injecting step injects individual neutral beams of neutral atomic hydrogenparticles into the magnetically confined plasma, and said injecting step varies said neutral beams of neutral atomic hydrogen particles in time as to energy and intensity in accordance with the requirements of optimum plasma stability in the magnetically confined plasma for effecting the production and control thereof.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |