Terzan 6      c
 3 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)=     1.626 +-  0.133
 a(1)=     2.277 +-  0.204
 a(2)=     0.521 +-  0.186
Power-of-x coeffients a(0)+a(1)x+a(2)x^2+..., where x=r
 a(0)=    -0.8647
 a(1)=     0.6602
 a(2)=     1.2452
log r(arcsec)   mu_V    mu_V(fitted)  residual   weight  data set