When Water is no Longer Heaven Sent: Comparative Pricing Analysis in an AGE Model

In this paper we present a applied general equilibrium model with special features that allows for comparative analysis of different pricing scheme. We look at Boiteux-Ramsey Pricing, Marginal Cost Pricing as well as an arbitrary water pricing increase for the agriculture sectors. A standard AGE was adapted by explicitly modeling water production with its different technologies, water demand by different users also needed to be refined since they are generally modeled with fixed coefficient with no substitution allowed. Results show that the choice of applying one policy over another can rely on the water management authorities (or government)objectives. If considering economic efficiency and water conservation the Boiteux-Ramsey pricing seems to be the best alternative. Moreover, we show that BRP become more clearly advantageous vs MCP the more rigid (small capacities to substitute water for other inputs) the economy's agents.Water, Taxation, Incidence, Computable General Equilibrium Model, Boiteux-Ramsey Pricing, Marginal Cost Pricing

Poverty Analysis Within a General Equilibrium Framework

The main objective of this paper is to show how Social Accounting Matrices (SAM) and Computable General Equilibrium (CGE) Models can be used to highlight and address issues related to income distribution and poverty. The paper is divided into two major parts. Part 1 presents the concept of the SAM as a comprehensive, consistent and disaggregated data system and shows how the SAM methodology can be used to analyze issues related to income distribution and, in a much more limited way, poverty. Part 2 is devoted to the presentation of a CGE model calibrated on an archetype African SAM (same as above). One innovation in the specification of the present CGE is that it goes part way in endogenizing the poverty line and the resulting poverty incidence among the different socioeconomic household groups and representing income distribution with a flexible Beta distribution function and using the F-G-T additively decomposable class of poverty measures. The model is used to simulate the impact of two exogenous shocks (a fall in the price of the export crop and an import tariff reform) specifically on poverty.Poverty, Computable General Equilibrium Model, Input Output Models

A computationally-efficient, semi-implicit, iterative method for the time-integration of reacting flows with stiff chemistry

A semi-implicit preconditioned iterative method is proposed for the time-integration of the stiff chemistry in simulations of unsteady reacting flows, such as turbulent flames, using detailed chemical kinetic mechanisms. Emphasis is placed on the simultaneous treatment of convection, diffusion, and chemistry, without using operator splitting techniques. The preconditioner corresponds to an approximation of the diagonal of the chemical Jacobian. Upon convergence of the sub-iterations, the fully-implicit, second-order time-accurate, Crank–Nicolson formulation is recovered. Performance of the proposed method is tested theoretically and numerically on one-dimensional laminar and three-dimensional high Karlovitz turbulent premixed n-heptane/air flames. The species lifetimes contained in the diagonal preconditioner are found to capture all critical small chemical timescales, such that the largest stable time step size for the simulation of the turbulent flame with the proposed method is limited by the convective CFL, rather than chemistry. The theoretical and numerical stability limits are in good agreement and are independent of the number of sub-iterations. The results indicate that the overall procedure is second-order accurate in time, free of lagging errors, and the cost per iteration is similar to that of an explicit time integration. The theoretical analysis is extended to a wide range of flames (premixed and non-premixed), unburnt conditions, fuels, and chemical mechanisms. In all cases, the proposed method is found (theoretically) to be stable and to provide good convergence rate for the sub-iterations up to a time step size larger than 1 μs. This makes the proposed method ideal for the simulation of turbulent flames

High-precision measurement of the half-life of 62^{62}Ga

The beta-decay half-life of 62Ga has been studied with high precision using on-line mass separated samples. The decay of 62Ga which is dominated by a 0+ to 0+ transition to the ground state of 62Zn yields a half-life of T_{1/2} = 116.19(4) ms. This result is more precise than any previous measurement by about a factor of four or more. The present value is in agreement with older literature values, but slightly disagrees with a recent measurement. We determine an error weighted average value of all experimental half-lives of 116.18(4) ms.Comment: 9 pages, 5 figures, accepted for publication in PR

The heavy quark search at the LHC

We explore further the discovery potential for heavy quarks at the LHC, with emphasis on the $t'$ and $b'$ of a sequential fourth family associated with electroweak symmetry breaking. We consider QCD multijets, $t\bar{t}+\rm{jets}$, $W+\rm{jets}$ and single $t$ backgrounds using event generation based on improved matrix elements and low sensitivity to the modeling of initial state radiation. We exploit a jet mass technique for the identification of hadronically decaying $W$'s and $t$'s, to be used in the reconstruction of the $t'$ or $b'$ mass. This along with other aspects of event selection can reduce backgrounds to very manageable levels. It even allows a search for both $t'$ and $b'$ in the absence of $b$-tagging, of interest for the early running of the LHC. A heavy quark mass of order 600 GeV is motivated by the connection to electroweak symmetry breaking, but our analysis is relevant for any new heavy quarks with weak decay modes.Comment: 12 pages, 7 figure

Unique Identification of Lee-Wick Gauge Bosons at Linear Colliders

Grinstein, O'Connell and Wise have recently presented an extension of the Standard Model (SM), based on the ideas of Lee and Wick (LW), which demonstrates an interesting way to remove the quadratically divergent contributions to the Higgs mass induced by radiative corrections. This model predicts the existence of negative-norm copies of the usual SM fields at the TeV scale with ghost-like propagators and negative decay widths, but with otherwise SM-like couplings. In earlier work, it was demonstrated that the LW states in the gauge boson sector of these models, though easy to observe, cannot be uniquely identified as such at the LHC. In this paper, we address the issue of whether or not this problem can be resolved at an $e^+e^-$ collider with a suitable center of mass energy range. We find that measurements of the cross section and the left-right polarization asymmetry associated with Bhabha scattering can lead to a unique identification of the neutral electroweak gauge bosons of the Lee-Wick type.Comment: 16 pages, 6 figures; discussion and references adde