description

Safety factor (\(q\)) gives the number of toroidal turns necessary for the magnetic field line at the given magnetic surface to reach its original position poloidally. On large aspect ratio circular tokamaks (like GOLEM), where the major radius (\(R\)) is much larger than the minor radius (\(r_0\)), it can be approximated by: \[q(r,t)= \dfrac{r}{R} \dfrac{B_t(t)}{B_p(r,t)}, \label{eq:q_def}\] where \(R\) is the major radius of the magnetic axis. An illustration for the meaning of the safety factor can be seen on Figure [fig:q].