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Projectile-power-compressed magnetic-field pulse generator (open access)

Projectile-power-compressed magnetic-field pulse generator

Design considerations and experimental results are presented of a compressed magnetic field pulsed energy source. A 100-mm-diameter, gun-fired projectile of approx. 2MJ kinetic energy was the input energy source. An initial magnetic field was trapped and compressed by the projectile. With a shorted load, a magajoule in a nanohenry was the design goal, i.e., 50 percent energy transformation from kinetic to magnetic. Five percent conversion was the highest recorded before gauge failure.
Date: March 17, 1983
Creator: Barlett, R.H.; Takemori, H.T. & Chase, J.B.
System: The UNT Digital Library
Positrons from supernova and the origin of the galactic-center positron-annihilation radiation (open access)

Positrons from supernova and the origin of the galactic-center positron-annihilation radiation

The emission of positrons from supernova ejecta is dicussed in terms of the galactic-center annihilation radiation. The positrons from the radioactive sequences /sup 56/Ni..-->../sup 56/Co..-->../sup 56/Fe are the most numerous source from supernova. Only type I supernova will allow a significant fraction to escape the expanding ejecta. For a neutron star model of a type I SN a fraction 4 x 10/sup -3/ of the escaped positron is enough to create the observed several year fluctuation of the annihilation radiation. The likelihood of this model is discussed in terms of other astrophysical evidence as well as the type I SN light curve.
Date: March 17, 1983
Creator: Colgate, S. A.
System: The UNT Digital Library
Mechanism of the optogalvanic effect in a hollow-cathode discharge (open access)

Mechanism of the optogalvanic effect in a hollow-cathode discharge

There are two significantly different mechanisms proposed for the origin of the optogalvanic effect in a hollow-cathode discharge: (1) laser excitation of atoms to higher electronic states leads to an increased cross section for electron impact ionization, with the result that the excited atom becomes ionized and the conductivity of the discharge increases; and (2) laser excitation of atoms to higher electronic states perturbs the equilibrium established between the electron temperature and the atomic excitation temperature. Superelastic collisions between the electrons and the laser-excited atoms restore the equilibrium, with the excess energy ending up in an increased electron temperature and therefore an increased conductivity of the discharge. Both mechanisms undoubtedly proceed simultaneously and what needs to be determined is their relative importance at different discharge conditions and different excitation conditions. This is important because laser isotope enrichment schemes have been proposed using selective excitation in a hollow-cathode discharge. In order for these schemes to work, (1) must be the predominant mechanism. We have measured the optogalvanic signal, concentration of uranium atoms, impedance of the discharge, and electron temperature as a function of the discharge current in a neon-filled uranium hollow-cathode discharge. The hollow cathode operating characteristics are used as input …
Date: June 17, 1983
Creator: Keller, Richard A.; Warner, Bruce E.; Zalewski, Edward F.; Dyer, P.; Engleman, Rolf, Jr. & Palmer, Byron A.
System: The UNT Digital Library
Leak testing and repair of fusion devices (open access)

Leak testing and repair of fusion devices

The leak testing, reporting and vacuum leak repair techniques of the MFTF yin-yang number one magnet system, the world's largest superconducting magnet system, are discussed. Based on this experience, techniques will be developed for testing and repairing leaks on the 42 MFTF-B magnets. The leak-hunting techniques for the yin-yang magnet systems were applied to two helium circuits (the coil bundle and guard vacuum; both require helium flow for magnet cooldown), their associated piping, liquid nitrogen radiation shields, and piping. Additionally, during MFTF-B operation there will be warm water plasma shields and piping that require leak checking.
Date: June 17, 1983
Creator: Kozman, T. A.
System: The UNT Digital Library
Experiments to study the feasibility of making an x-ray laser at the Novette laser facility (open access)

Experiments to study the feasibility of making an x-ray laser at the Novette laser facility

We will discuss a set of experiments which are designed to study approaches to and search for the existence of amplified spontaneous emission at photon energies of 42.3, 53.6, 119.0, and 153.0 eV. The schemes utilize pumping from the Novette laser operated with cylindrical optics at 5 TW/beam and 100 psec.
Date: May 17, 1983
Creator: Matthews, D.L.; Hagelstein, P. & Kauffman, R.
System: The UNT Digital Library
Status of the Lawrence Berkeley Laboratory and the Lawrence Livermore National Laboratory (LLNL) free electron laser (FEL). Revision 1 (open access)

Status of the Lawrence Berkeley Laboratory and the Lawrence Livermore National Laboratory (LLNL) free electron laser (FEL). Revision 1

A high-gain FEL experiment using the 10 kA, 4.5 MeV Experimental Test Accelerator (ETA) is described.
Date: November 17, 1983
Creator: Orzechowski, T. J.; Moebus, M. C.; Penko, F. A.; Prosnitz, D.; Rogers, D.; Chavis, C. S. et al.
System: The UNT Digital Library
Sodium/water pool-deposit bed model of the CONACS code. [LMFBR] (open access)

Sodium/water pool-deposit bed model of the CONACS code. [LMFBR]

A new Pool-Bed model of the CONACS (Containment Analysis Code System) code represents a major advance over the pool models of other containment analysis code (NABE code of France, CEDAN code of Japan and CACECO and CONTAIN codes of the United States). This new model advances pool-bed modeling because of the number of significant materials and processes which are included with appropriate rigor. This CONACS pool-bed model maintains material balances for eight chemical species (C, H/sub 2/O, Na, NaH, Na/sub 2/O, Na/sub 2/O/sub 2/, Na/sub 2/CO/sub 3/ and NaOH) that collect in the stationary liquid pool on the floor and in the desposit bed on the elevated shelf of the standard CONACS analysis cell.
Date: December 17, 1983
Creator: Peak, R.D.
System: The UNT Digital Library
High image quality sub 100 picosecond gated framing camera development (open access)

High image quality sub 100 picosecond gated framing camera development

A major challenge for laser fusion is the study of the symmetry and hydrodynamic stability of imploding fuel capsules. Framed x-radiographs of 10-100 ps duration, excellent image quality, minimum geometrical distortion (< 1%), dynamic range greater than 1000, and more than 200 x 200 pixels are required for this application. Recent progress on a gated proximity focused intensifier which meets these requirements is presented.
Date: November 17, 1983
Creator: Price, R. H. & Wiedwald, J. D.
System: The UNT Digital Library
Experiences with fast breeder reactor education in laboratory and short course settings (open access)

Experiences with fast breeder reactor education in laboratory and short course settings

The breeder reactor industry throughout the world has grown impressively over the last two decades. Despite the uncertainties in some national programs, breeder reactor technology is well established on a global scale. Given the magnitude of this technological undertaking, there has been surprisingly little emphasis on general breeder reactor education - either at the university or laboratory level. Many universities assume the topic too specialized for including appropriate courses in their curriculum - thus leaving students entering the breeder reactor industry to learn almost exclusively from on-the-job experience. The evaluation of four course presentations utilizing visual aids is presented.
Date: January 17, 1983
Creator: Waltar, A.E.
System: The UNT Digital Library