Single and double pi^{-}/pi^{+} ratios in heavy-ion reactions as probes of the high-density behavior of the nuclear symmetry energy

Based on an isospin- and momentum-dependent hadronic transport model IBUU04, effects of the nuclear symmetry energy on the single and double pi^{-}/pi^{+}ratios in central reactions of ^{132}Sn+^{124}Sn and ^{112}Sn+^{112}Sn at a beam energy of 400 MeV/nucleon are studied. It is found that around the Coulomb peak of the single pi^{-}/pi^{+} ratio the double pi^{-}/pi^{+} ratio taken from the two isotopic reactions retains about the same sensitivity to the density dependence of nuclear symmetry energy. Because the double pi^{-}/pi^{+}ratio can reduce significantly the systematic errors, it is thus a more effective probe for the high-density behavior of the nuclear symmetry energy.Comment: 11 pages, 3 figures, to appear in Physics Review

Progress Towards Determining the Density Dependence of the Nuclear Symmetry Energy Using Heavy-Ion Reactions

The latest development in determining the density dependence of the nuclear symmetry energy using heavy-ion collisions is reviewed. Within the IBUU04 version of an isospin- and momentum-dependent transport model using a modified Gogny effective interaction, recent experimental data from NSCL/MSU on isospin diffusion are found to be consistent with a nuclear symmetry energy of $E_{sym}(\rho)\approx 31.6(\rho /\rho_{0})^{1.05}$ at subnormal densities. Predictions on several observables sensitive to the density dependence of the symmetry energy at supranormal densities accessible at GSI and the planned Rare Isotope Accelerator (RIA) are also made.Comment: 10 pages. Talk given at the 21st Winter Workshop on Nuclear Dynamics, Breckenridge, Colorado, USA, Feb. 5-12, 2005. To appear in Heavy-Ion Physics (2005

Diversification, Relatedness, And Firm Performance: Empirical Evidence From China

The relationship between diversification, relatedness and performance has long been a controversial issue in mainstream strategic management research. Research in this area, however, has focused primarily on developed countries. This study argues that the conclusions drawn from developed countries may not apply to developing countries. In an investigation of 227 publicly-listed companies in China, this study found that: 1) firm scale significantly contributes to the improvement of economic performance; 2) relatedness correlates negatively with firm performance, and 3) the relationship between diversification and performance fits the intermediate model. This study also provided evidence to support the argument that differences do exist in the rationales between firms in developed and developing countries

Advantages and disadvantages of retrenchment

The stability of the job in a state or country usually depends on the condition of the economy in that country or state. Malaysia and many countries around the world have faced several economic downturns and recessions over the past year, this causes the slowdown of the economy and poor business conditions resulting in a slump in business due to the significant drop of the company’s profit. Companies that are suffering big losses may choose to restructure or reorganize their businesses to reduce the impact of poor business conditions. The wave of retrenchment usually hit the sectors of manufacturing, transportation, communication, commerce, and finance