NGC5024 (M53)
 6 iterations.
Chebyshev coeffients a(0)T_0(u)+a(1)T_1(u)+..., where u is log (r/arcsec) mapped to [-1,1]
 a(0)=    22.315 +-  0.103
 a(1)=     5.945 +-  0.171
 a(2)=     0.996 +-  0.132
Power-of-x coeffients a(0)+a(1)x+a(2)x^2+..., where x=1+(r/r_c)^2, r_c=1.42
 a(0)=     6.2078
 a(1)=     1.0180
 a(2)=     0.5364
log r(arcsec)   mu_V    mu_V(fitted)  residual   weight  data set