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Efforts to stabilize the M = 2 helical instability in ATC (open access)

Efforts to stabilize the M = 2 helical instability in ATC

Experiments show that there is no difficulty about interacting with a 2/ 1 mode in ATC, and that given sufficient gain and a harmonic-free control winding the probability of stabilizing it is good. Control by steadily applied, DC quadrupole fields, on the other hand, on the basis of experiments with ATC as well as Pulsator, would seem at this juncture to have a small chance of success. Finally, the high currents achieved in gettered discharges offer the possibility that if control of wall emission can be achieved--e.g., with a divertor--one may simultaneously achieve a measure of control of the 2/1 and higher modes. (auth)
Date: January 1, 1975
Creator: Bol, K.; Ellis, R. A., Jr. & Hsuan, H.
System: The UNT Digital Library
A 218 neutron group master cross section library for criticality safety studies (open access)

A 218 neutron group master cross section library for criticality safety studies

The AMPX system was used to generate a P$sub 3$ 218 neutron group master cross-section library from ENDF/B-IV data for the fuel, structural, and neutron- absorbing materials tabulated. The library is the data base for the generation of broad-group cross sections for shipping cask calculations and other criticality safety analyses using codes such as KENO and ANISN. Selection of the fine-group energy structure for the 3-eV to 20-MeV energy range included consideration of the resonance structure of prominent nuclei, the thresholds of important reactions, and the fission spectra. For 10$sup -5$ less than or equal to E/sub n/ less than 3 eV, 78 closely spaced thermal groups were chosen to examine the effects of low-energy resonances and thermal-neutron upscatter. Distribution of the 218 groups within the Hansen-Roach 16-group boundaries is shown. Adequacy of the group structure and validity of selected data sets from the library were tested by P$sub 3$S$sub 8$ XSDRNPM calculations of k-eff for two benchmark critical experiments; first, the 4.9 percent-enriched UO$sub 2$F$sub 2$- H$sub 2$O solution critical sphere experiment of Johnson and Cronin was analyzed, and, second, the 93.2 percent-enriched UO$sub 2$F$sub 2$-H$sub 2$O solution critical sphere experiment of Fox was analyzed. (auth)
Date: January 1, 1975
Creator: Ford, W. E., III; Westfall, R. M. & Webster, C. C.
System: The UNT Digital Library
Spatial and temporal variations in the interstitial water chemistry of Chesapeake Bay sediments (open access)

Spatial and temporal variations in the interstitial water chemistry of Chesapeake Bay sediments

None
Date: January 1, 1975
Creator: Matisoff, G.; Bricker, O. P., III; Holdren, G. R., Jr. & Kaerk, P.
System: The UNT Digital Library
Radioactive isotopes on the Moon (open access)

Radioactive isotopes on the Moon

A limited review of experiments and studies of radioactivity and isotope ratios in lunar materials is given. Observations made on the first few millimeters of the surface where the effects of solar flare particles are important, some measurements on individual rocks, and some studies of radioactivities produced deep in the lunar soil by galactic cosmic rays, are among the experiments discussed. (GHT)
Date: January 1, 1975
Creator: Davis, R., Jr.
System: The UNT Digital Library
Hydrogen transport in iron and steel (open access)

Hydrogen transport in iron and steel

None
Date: January 1, 1975
Creator: Louthan, M. R. Jr.; Derrick, R. G.; Donovan, J. A. & Caskey, G. R., Jr.
System: The UNT Digital Library
New approach to timing: the fast--fast system (open access)

New approach to timing: the fast--fast system

A dual channel constant fraction timing discriminator incorporating multiple energy windows and coincidence logic has been developed. Incorporation of energy discrimination and fast coincidence logic into the timing channel has distinct advantages in terms of system simplicity, stability and data rates. A prototype applying the F$sup 2$ approach has been constructed and tested. The system gives a $sup 60$Co FWHM of approximately 210 psec at a singles rate of greater than 7.5 x 10$sup 5$ sec$sup -1$ (approximately 1200 coincidences/sec). (auth)
Date: January 1, 1975
Creator: Hardy, W. H., II & Lynn, K. G.
System: The UNT Digital Library
Absorption and luminescence of glasses during electron irradiation (open access)

Absorption and luminescence of glasses during electron irradiation

None
Date: January 1, 1975
Creator: Swyler, K. J.; Hardy, W. H., II & Levy, P. W.
System: The UNT Digital Library
Radiation induced coloring of glasses measured during and after electron irradiation (open access)

Radiation induced coloring of glasses measured during and after electron irradiation

None
Date: January 1, 1975
Creator: Swyler, K. J.; Hardy, W. H., II & Levy, P. W.
System: The UNT Digital Library