Negative-potential operation of TMX-Upgrade (open access)

Negative-potential operation of TMX-Upgrade

A tandem-mirror configuration can be created by combining hot electron end-cell plasmas with neutral-beam pumping. A region of large negative potential formed in each end cell confines electrons in the central cell. The requirement of charge neutrality causes the central-cell potential to become negative with respect to ground in order to equate ion loss to electron loss. Start-up and formation of the axial potential distribution, neutral-beam pumping, hot electron feed, electron-cyclotron-resonance heating (ECRH) power requirements, and stability are discussed in general terms. Each of these considerations impose constraints on the operation of TMX as a negative machine. The start-up requirements and scenario are also presented. Work on the design and analysis of negative tandems is continuing. The status of work to date is presented here with problem areas for future work identified.
Date: April 6, 1982
Creator: Poulsen, P.; Allen, S. L. & Baldwin, D. E.
Object Type: Report
System: The UNT Digital Library
Sources of hot electrons in laser-plasma interaction with emphasis on Raman and turbulence absorption (open access)

Sources of hot electrons in laser-plasma interaction with emphasis on Raman and turbulence absorption

Heating targets with high power lasers results in a sizable fraction of the absorbed energy going into electrons of temperature much greater than thermal which can pre-heat the pellet core and accelerate fast ion blowoff which results in poor momentum transfer and hence poor compression efficiency. The present emphasis is to build lasers of higher frequency, ..omega../sub 0/, which at the same W/cm/sup 2/ results in more absorption into cooler electrons. Two physical reasons are that the laser can propagate to a higher electron density, n, infinity..omega../sub 0//sup 2/ resulting in more collisional inverse bremsstrahlung absorption proportional to n, and because the hot temperatures from some plasma absorption processes increase as the oscillatory velocity of an electron in the laser electric field v/sub 0//c = eE/(m/sub e/..omega../sub 0/). The heated electron temperatures from other plasma processes (Raman for example approx.(m/sub e//2)v/sup 2//sub phase/ and the higher laser frequency helps by increasing the competing collisional absorption and decreasing the Raman gain.
Date: April 6, 1982
Creator: Estabrook, K.; Kruer, W. L.; Phillion, D. W.; Turner, R. E. & Campbell, E. M.
Object Type: Article
System: The UNT Digital Library
Texas Register, Volume 7, Number 26, Pages 1397-1436, April 6, 1982 (open access)

Texas Register, Volume 7, Number 26, Pages 1397-1436, April 6, 1982

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: April 6, 1982
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History