Two-parameter modified rigid rotor radial equilibrium model for field-reversed configurations

A new equilibrium pressure profile extending the Rigid-Rotor (RR) model with a simple unified expression $P=P(\psi;\beta_{s},\alpha, \sigma)$ for both inside and outside separatrix is proposed, in which radial normalized field-reversed configuration (FRC) profiles pressure, magnetic field, current can be determined by only two dimensionless parameters $\beta_s\equiv P_s/2\mu_0B_e^2$ $\delta_s\equiv L_{ps}/R_s$, where $P_s$ thermal at separatrix, $B_e$ external field strength, $L_{ps}$ scale length $R_s$ radius. This modified rigid rotor (MRR) has sufficient flexibility to accommodate narrow scrape of layer (SOL) width hollow density profiles, used fit experimental measurements satisfactorily. Detailed one-dimensional (1D) characteristics MRR are investigated analytically numerically, results also confirmed two-dimensional (2D) numerical solutions.