Number density D, mass density ρ, and average mass per star as a function of the logarithm of the distance from the centre r_c. A bin size of 2 pc in steps of 1 pc is used within 10 pc; beyond this the bin size is increased to 4 pc to get a better signal-to-noise ratio. From top to bottom: the number density D as a green curve, the observed mass density (blue curve), and a density distribution (black dashed line) from a Plummer model (Eq. (5)) with M_t = 483 M_⊙ and r_co = 3.7 pc, the average mass per star (ρ/D) as a red line.