It is shown that ion thermal conductivity close to the magnetic axis in tokamaks is reduced by a factor of |S|5/3 if (Mi/Me)2/3(Te/Ti) 4/3/|S|5/3≫ 1. Here, S is the orbit squeezing factor, Mi(Me) is the ion (electron) mass, and Ti(Te) is the ion (electron) temperature. The reduction reflects both the increase of the fraction of trapped particles by a factor of \S\1/3, and the decrease of the orbit size in units of the poloidal flux ψ by a factor of |S|2/3.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics