Left: contours of the general multiparametric penalty function in θ,φ, with the largest plus symbol indicating the minimal value, and the other symbols indicating the next two best values. As for the binary envelope fit, the best fit cone solutions are seen to exist in two degenerate islands. Right: the various fit parameters, defined in Sect. 3, of the multiparametric model as a function of the penalty. The exponents γ,δ and ν are dimensionless, α_c is in degrees, and velocity scale v₀ and escape velocity v_e are in cm s^-1. All of the parameters tend to converge at the fit optimum, with the two islands of solutions giving similar values.