Simons Hour Talk

Direct Optimization of Fast-Ion Confinement in Stellarators
Mar 30, 2023, 10:00 am – 11:00 am


Event Description

Abstract: Confining energetic ions such as alpha particles is a prime concern in the design of stellarators. However, directly measuring alpha confinement through numerical simulation of guiding-center trajectories has been considered to be too computationally expensive and noisy to include in the design loop, and instead has been most often used only as a tool to assess stellarator designs post hoc. In its place, proxy metrics, simplified measures of confinement, have often been used to design configurations because they are computationally more tractable and have been shown to be effective. Despite the success of proxies, it is unclear what is being sacrificed by using them to design the device rather than relying on direct trajectory calculations. In this study, we optimize stellarator designs for improved alpha particle confinement without the use of proxy metrics. In particular, we numerically optimize an objective function that measures alpha particle losses by simulating alpha particle trajectories. While this method is computationally expensive, we find that it can be used successfully to generate configurations with low losses.

Talk time in other timezones:
AEDT  1:00 AM Fri 31 Mar,
JST  11:00 PM Fri 31 Mar,
CEST  4:00 PM Thu 30 Mar,
BST   3:00 PM Thu 30 Mar,
UTC  14:00    Thu 30 Mar,
EDT  10:00 AM Thu 30 Mar,
CDT   9:00 AM Thu 30 Mar,
MDT   8:00 AM Thu 30 Mar,
MST   7:00 AM Thu 30 Mar
Simons Foundation