Radial density profile of KiDS-UFD-1 (left). Here, r_ell is the elliptical radius defined in Eq. (4) in Martin et al. (2008). The red solid line refers to the best-fit model with the parameters derived via the MCMC approach described in Sect. 4.3, while the gray lines represent 1000 random extractions from the posterior distributions of the free parameters of the model. Relative position of all stars filtered by the best-fit isochrone with respect to the galaxy center (right). The red dashed and solid ellipses have ellipticity and position angle derived from the MCMC procedure and semi-major axes of 2 × r_h and 4 × r_h, respectively. Cyan diamonds indicate the relative position of the five HB stars.