Numerical study on transition point of relaxed mode for reversed field pinch with partial loss of helicity

Numerical study on the transition point of the relaxed mode for the β = 0 reversed field pinch plasma is presented, where the relaxed state is expressed by μ0J = λ0g(ψ)B with various profiles of g(ψ). It is shown that the smallest positive eigenvalue in the first order approximation, which gives the transition point, increases gradually as the g(ψ) profile deviates further from g(ψ) = 1 for the idealized model by Taylor. It is shown that the present numerical results on the transition point become closer to the relevant experimental data compared with the idealized case obtained by Taylor. The numerical results are also shown to offer a mechanism which yields a profile consistency on the experimental g(ψ) profile. (author)