Georgia State University

About: Georgia State University is a education organization based out in Atlanta, Georgia, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 13988 authors who have published 35895 publications receiving 1164332 citations. The organization is also known as: GSU & Georgia State.

Nuclear modification of electron spectra and implications for heavy quark energy loss in Au+Au collisions at sNN=200GeV

Abstract: The PHENIX experiment has measured midrapidity ([FORMULA: SEE TEXT]) transverse momentum spectra ([FORMULA: SEE TEXT]) of electrons as a function of centrality in Au+Au collisions at [FORMULA: SEE TEXT]. Contributions from photon conversions and from light hadron decays, mainly Dalitz decays of pi0 and eta mesons, were removed. The resulting nonphotonic electron spectra are primarily due to the semileptonic decays of hadrons carrying heavy quarks. Nuclear modification factors were determined by comparison to nonphotonic electrons in p+p collisions. A significant suppression of electrons at high pT is observed in central Au+Au collisions, indicating substantial energy loss of heavy quarks.

Heavy-quark production in p + p and energy loss and flow of heavy quarks in Au + Au collisions at √sNN=200 GeV

Abstract: Transverse momentum spectra of electrons (p(T)(e)) from semileptonic weak decays of heavy-flavor mesons in the range of 0.3 < p(T)(e) < 9.0 GeV/c have been measured at midrapidity (|y| < 0.35) by the PHENIX experiment at the Relativistic Heavy Ion Collider in p + p and Au + Au collisions at root s(NN) = 200 GeV. In addition, the azimuthal anisotropy parameter v(2) has been measured for 0.3 < p(T)(e) < 5.0 GeV/c in Au + Au collisions. The substantial modification in the p(T)(e) spectra in Au + Au compared with p + p collisions as well as the nonzero v(2) indicate substantial interactions and flow of heavy quarks in traversing the produced medium. Comparisons of these observables with detailed theoretical calculations can be used to identify the nature of these interactions and to quantify their extent.

Defining Social Enterprise Across Different Contexts A Conceptual Framework Based on Institutional Factors

Abstract: Over the past several decades the concept of social enterprise has grown dramatically in many regions of the world. Defined as the use of nongovernmental, market-based approaches to address social issues, social enterprise often provides a ‘business’ source of revenue for many types of socially oriented organizations and activities.1 However, within these broad parameters, world regions have come to identify different definitions and concepts with the social enterprise movement in their areas (Kerlin, 2006). This variation has also resulted in considerable debate among researchers and practitioners on how to define the concept (Mair et al., 2006; Light, 2008). To address these difficulties, this research draws on the theory of historical institutionalism to advance understanding of how context influences the development of social enterprise as well as to propose a preliminary conceptual framework for social enterprise that spans regional differences in the term.

Does Social Security Privatization Produce Efficiency Gains

Abstract: While privatizing social security can improve labor supply incentives, it can also reduce risk sharing. We analyze a 50% privatization using an overlapping-generations model where heterogeneous agents with elastic labor supply face idiosyncratic earnings shocks and longevity uncertainty. When wage shocks are insurable, privatization produces about $18,100 of extra resources for each future household after all transitional losses have been compensated for with lump-sum taxes. When wages are not insurable, privatization reduces efficiency by about $2,400 per future household. We check the robustness of these results to different model specifications as well as policy reforms and arrive at several surprising conclusions. First, privatization performs better in a closed economy, where interest rates decline with capital accumulation, than in an open economy. Second, privatization also performs better when an actuarially fair private annuity market does not exist. Third, government matching of private contributions on a progressive basis is not very effective at restoring efficiency and can actually cause harm.