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 …

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.

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 Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents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.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Sound recording of Carlotta Herman Mellon being interviewed by G. Morris.

Sound recording of Carlotta Herman Mellon being interviewed by G. Morris.

Weekly newspaper from Sulphur Springs, Texas that includes local, state, and national news along with advertising.

Photograph used for a story in the Daily Oklahoman newspaper. Caption: "King of the Hungle Dave Shuler prepares to cut the cake."

Photograph used for a story in the Daily Oklahoman newspaper. Caption: "Mike Larsen and Linda Skrasek get ready for the art benefit Sunday at Woodland Cabin Gallery, NW 62 and Harvey."

Photograph used for a story in the Oklahoma Times newspaper. Caption: "Oklahoma City Zoo resident Woody the Beaver enjoys the attentions of Karen Hickner, Kyle Edwards and Jennifer Hufhes, future members of the zoo's Junior Audubon Club."

Photograph used for a story in the Oklahoma Times newspaper. Caption: "Engineer Tom Tobin"

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Weekly newspaper from Harper, Texas that includes local, state, and national news along with advertising.

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.