A Class of Exactly Solvable Pairing Models

We present three classes of exactly solvable models for fermion and boson systems, based on the pairing interaction. These models are solvable in any dimension. As an example we show the first results for fermion interacting with repulsive pairing forces in a two dimensional square lattice. Inspite of the repulsive pairing force the exact results show attractive pair correlations.Comment: 5 pages, 1 figur

EVALUATING NON-PRICE WATER DEMAND POLICIES DURING SEVERE DROUGHTS

This research examines how differing frequencies of water use restrictions affected per-capita water demand in three medium-sized municipalities along the Front Range of Colorado during the 2002 drought. Preliminary results indicate that while one- or two-day per week watering restrictions limit per capita water use, voluntary restrictions may actually promote overuse of water as consumers prepare for more stringent restrictions.Resource /Energy Economics and Policy,

MANURE BMP ADOPTION AMONG NORTH DAKOTA ANIMAL FEED OPERATIONS

Regulations governing animal waste storage are primarily a state-level issue. Protecting water resources from animal waste contamination will depend upon how effective state-level animal waste regulations are in encouraging livestock producers to handle waste appropriately. Survey results from North Dakota indicate beef cattle feeding operations do not always comply with state regulations requiring adoption of manure storage BMP's. This is most likely due to incomplete inspection schedules by the regulatory agency. Statistical results suggest herd size plays a much larger role than regulation in promoting adoption of manure storage BMP's.Livestock Production/Industries,

FARM LEVEL IRRIGATION TECHNOLOGY DECISIONS OVER TIME

A time-series cross-sectional model of irrigation technology choice is developed for an irrigation district in California's Central Valley to show how changes in the relative price of irrigation water and variations in water supply over time influence the choice of irrigation system. Results indicate changes in crop mix and variations in water supply are at least as important as price in determining the choice of irrigation system.Farm Management,

THE IMPORTANCE OF TARIFF STRUCTURE IN CONSERVATION PRICING

Resource /Energy Economics and Policy,

Evaluating Non-Price Water Demand Policies During Severe Droughts

Western states and provinces live under constant drought threat. When and how to time restrictions on outdoor watering are crucial management issues. The effectiveness of various policies is assessed using experience from Colorado during a severe drought.Environmental Economics and Policy,

Deuteron formation in nuclear matter

We investigate deuteron formation in nuclear matter at finite temperatures within a systematic quantum statistical approach. We consider formation through three-body collisions relevant already at rather moderate densities because of the strong correlations. The three-body in-medium reaction rates driven by the break-up cross section are calculated using exact three-body equations (Alt-Grassberger-Sandhas type) that have been suitably modified to consistently include the energy shift and the Pauli blocking. Important quantities are the lifetime of deuteron fluctuations and the chemical relaxation time. We find that the respective times differ substantially while using in-medium or isolated cross sections. We expect implications for the description of heavy ion collisions in particular for the formation of light charged particles at low to intermediate energies.Comment: 19 pages, 5 figure

Generalized Second-Order Thomas-Fermi Method for Superfluid Fermi Systems

Using the $\hbar$-expansion of the Green's function of the Hartree-Fock-Bogoliubov equation, we extend the second-order Thomas-Fermi approximation to generalized superfluid Fermi systems by including the density-dependent effective mass and the spin-orbit potential. We first implement and examine the full correction terms over different energy intervals of the quasiparticle spectra in calculations of finite nuclei. Final applications of this generalized Thomas-Fermi method are intended for various inhomogeneous superfluid Fermi systems.Comment: 8 pages, 10 figures, PR

Comparison of Regional and Statewide Impacts on Salinity Mitigation in the Arkansas River Valley

The Arkansas River in Colorado has a major salinity problem, due to agricultural runoff caused by irrigation. It is necessary to see how on-farm net sales, regional and state employment and income levels are affected by alternative aquifer recharge rates. The positive impacts were greatest for the 40% recharge rate.Resource /Energy Economics and Policy,