XMASS

The XMASS detector is a large single phase liquid Xenon scintillator.After its feasibility had been studied using a 100 kg size prototype detector, an 800 kg size detector is being built for dark matter search with the sensitivity of $10^{-45} {\rm cm}^2$ region in spin-independent cross section. The results of R\&D study for 800 kg detector, especially ultra low background technologies, and the prospects of the experiment are described.Comment: 6 pages, 7 figures, for the proceedings of the 1st International Workshop towards the Giant Liquid Argon Charge Imaging Experiment (GLA2010, will be published in Journal of Physics, Conference Series (Editors: T. Hasegawa and A. Rubbia)

Voting Equilibria in Multi-candidate Elections

We consider a general plurality voting game with multiple candidates, where voter preferences over candidates are exogenously given. In particular, we allow for arbitrary voter indierences, as may arise in voting subgames of citizen-candidate or locational models of elections. We prove that the voting game admits pure strategy equilibria in undominated strategies. The proof is constructive: we exhibit an algorithm, the “best winning deviation” algorithm, that produces such an equilibrium in finite time. A byproduct of the algorithm is a simple story for how voters might learn to coordinate on such an equilibrium.