Pairing effect on the giant dipole resonance width at low temperature

The width of the giant dipole resonance (GDR) at finite temperature T in Sn-120 is calculated within the Phonon Damping Model including the neutron thermal pairing gap determined from the modified BCS theory. It is shown that the effect of thermal pairing causes a smaller GDR width at T below 2 MeV as compared to the one obtained neglecting pairing. This improves significantly the agreement between theory and experiment including the most recent data point at T = 1 MeV.Comment: 8 pages, 5 figures to be published in Physical Review

Simulating spatial variability of cereal yields from historical yield maps and satellite imagery

[Abstract]: The management of spatial variability of crop yields relies on the availability of affordable and accurate spatial data. Yield maps are a direct measure of the crop yields, however, costs and difficulties in collection and processing to generate yield maps results in poor availability of such data in Australia. In this study, we used historical mid-season normalised difference vegetation index (NDVI), generated from Landsat imagery over 4 years. Using linear regression model, the NDVI was compared to the actual yield map from a 257 ha paddock. The difference between actual and predicted yield showed that 77% and 93% of the paddock area had an error of <20% and <30%, respectively. The linear model obtained in the paddock was used to simulate crop yield for an adjoining paddock of 162 ha. On an average of 4 years, the difference between actual and simulated yield showed that 87% of the paddock had an error of <20%. However, this error varied from season to season. Paddock area with <20% error increased exponentially with decreasing in-crop rainfall between anthesis and crop maturity. Furthermore, the error in simulating crop yield also varied with the soil constraints. Paddock zones with high concentrations of subsoil chloride and surface soil exchangeable sodium percentage generally had higher percent of error in simulating crop yields. Satellite imagery consistently over-predicted cereal yields in areas with subsoil constraints, possibly due to chloride-induced water stress during grain filling. The simulated yield mapping methodology offers an opportunity to identify within-field spatial variability using satellite imagery as a surrogate measure of biomass. However, the ability to successfully simulate crop yields at farm scale or regional scale requires wider evaluation across different soil types and climatic conditions

Does Managerial ability matter for the choice of Seasoned Equity offerings?

We provide evidence that managerial ability is positively and significantly related to the issuance method decision of seasoned equity offerings (SEOs) in the U.S. market. Our result is robust after controlling for various internal and external governance mechanisms, addressing the problem of endogeneity, and adopting a number of alternative specifications. We further find that the impact of managerial ability on the SEO issuance choice is stronger for firms with higher information asymmetry, CEO duality and weaker governance settings. Overall, our study supports the notion that higher managerial ability is perceived as a positive quality certification on firm information environments

Do family firms pay less for external funding?

We examine the impact of family’s presence on the cost of raising external funds by family-run enterprises. Using a sample of Australian publicly listed firms, we find a significantly negative relation between cost of newly raised capital and family presence. Moreover, we show that this relationship varies with the quality of corporate governance and the quality of firm’s information environment. Further, we conduct several robustness checks and consistently find that our main results remain unchanged. Overall, our evidence suggests that family firms have easier access to external financing fostered by family involvement in the ownership and control