Robert J. Brecha

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The events of March 2011 at the nuclear power complex in Fukushima, Japan, raised questions about the safe operation of nuclear power plants, with early retirement of existing nuclear power plants being debated in the policy arena and considered by regulators. Also, the future of building new nuclear power plants is highly uncertain. Should nuclear power(More)
A degenerate gas of identical fermions is brought to collapse by the interaction with a Bose-Einstein condensate. We used an atomic mixture of fermionic potassium-40 and bosonic rubidium-87, in which the strong interspecies attraction leads to an instability above a critical number of particles. The observed phenomenon suggests a direction for manipulating(More)
We report on the Bose-Einstein condensation of potassium atoms, whereby quantum degeneracy is achieved by sympathetic cooling with evaporatively cooled rubidium. Because of the rapid thermalization of the two different atoms, the efficiency of the cooling process is high. The ability to achieve condensation by sympathetic cooling with a different species(More)
a r t i c l e i n f o We analyze the relationship between economic development and energy consumption in the context of greenhouse gas mitigation. The main contribution of this work is to compare estimates of energy thresholds in the form of minimum energy requirements to reach high levels of development with output projections of per capita final energy(More)
An experimental demonstration of a noninvasive optical probe of magnetic fields is presented. The technique used is magnetic rotation spectroscopy of the b(1)?(g)(+) - X(3)?(g)(-) band of oxygen near 760 nm. Ambient concentrations of oxygen at atmospheric pressure are sufficient to observe substantial signals. In addition, a diode laser is used as the light(More)
Small amounts of ellipticity in the nominally linearly polarized light used in magnetic rotation spectroscopy play an important role in determining the character of the signals developed in these experiments. For example, ellipticity introduced by stress-induced birefringence can easily influence such signals more than does a nonzero polarizer extinction(More)