Alpha Channeling with High-field Launch of Lower Hybrid Waves

Although lower hybrid waves are effective at driving currents in present-day tokamaks, they are expected to interact strongly with high-energy particles in extrapolating to reactors. In the presence of a radial alpha particle birth gradient, this interaction can take the form of wave amplification rather than damping. While it is known that this amplification more easily occurs when launching from the tokamak high-field side, the extent of this amplification has not been made quantitative. Here, by tracing rays launched from the high- field-side of a tokamak, the required radial gradients to achieve amplification are calculated for a temperature and density regime consistent with a hot-ion-mode fusion reactor. These simulations, while valid only in the linear regime of wave amplification, nonetheless illustrate the possibilities for wave amplification using high-field launch of the lower hybrid wave.Comment: 7 pages, 7 figure

The Political Cost of Public-Private Partnerships: Theory and Evidence from Colombian Infrastructure Development

Infrastructure public–private partnerships (PPPs) eschew traditional public management to provide distributive goods worldwide. Yet, in Colombia, the context of our study, both the promise of and voters' experience with PPPs hinder incumbent parties in elections when theories of distributive politics expect otherwise. We argue that negative experiences with PPPs introduce a sociotropic turn in individual voting: bad experience crowds out the possibility that promising a new project will improve a voter's own welfare. Studying what are, to our knowledge, all 109 Colombian PPP projects between 1998 and 2014, and over 8,700 individual survey responses, our evidence shows that vote intention for the incumbent executive or his party decreases as experience with more PPPs in respondents' districts increases. Our analysis and results introduce an important agenda for research into the political significance of these legacies of new public management