Maximizing Hadron Collider Sensitivity to Gauge-Mediated Supersymmetry Breaking Models

We consider typical hadron collider detector signals sensitive to delayed decays of the lightest neutralino to photon plus goldstino and demonstrate the potential for substantially increasing the portion of the general parameter space of a gauge-mediated supersymmetry breaking model that can be probed at the Tevatron.Comment: 11 pages, full postscript file is available via anonymous ftp at ftp://ucdhep.ucdavis.edu/gunion/gmsb.ps; incorrect labels on figures correcte

Exploring Quantum Phase Transitions with a Novel Sublattice Entanglement Scenario

We introduce a new measure called reduced entropy of sublattice to quantify entanglement in spin, electron and boson systems. By analyzing this quantity, we reveal an intriguing connection between quantum entanglement and quantum phase transitions in various strongly correlated systems: the local extremes of reduced entropy and its first derivative as functions of the coupling constant coincide respectively with the first and second order transition points. Exact numerical studies merely for small lattices reproduce several well-known results, demonstrating that our scenario is quite promising for exploring quantum phase transitions.Comment: 4 pages, 4 figure

Some university students are more equal than others: Evidence from England

This paper estimates the efficiency of students in English universities using Data Envelopment Analysis (DEA) and a new dataset which is able to capture the behaviour of university students. Taking as the output the classification of a university degree, we use as inputs teaching hours and quality, entry qualifications, and the effort level. We find that university students differ in terms of the efficiency with which they use inputs in producing good degrees. In a second stage, we explore the determinants of the efficiency of university students using a truncated regression model. Higher student efficiency is found to be positively and significantly related to university size, and negatively and significantly related to the proportion of part-time students and the number of academic staff. The quality of a university has no significant impact on the efficiency of its students once endogeneity of university quality is controlled for.