We turn our attention to Haffner 9 , a Milky Way open cluster whose previous fundamental parameter estimates are far from being in agreement .
In order to provide with accurate estimates we present high-quality Washington CT _ { 1 } and Johnson BVI photometry of the cluster field .
We put particular care in statistically clean the colour-magnitude diagrams ( CMDs ) from field star contamination , which was found a common source in previous works for the discordant fundamental parameter estimates .
The resulting cluster CMD fiducial features were confirmed from a proper motion membership analysis .
Haffner 9 is a moderately young object ( age \sim 350 Myr ) , placed in the Perseus arm -at a heliocentric distance of \sim 3.2 kpc- , with a lower limit for its present mass of \sim 160 M _ { \odot } and of nearly metal solar content .
The combination of the cluster structural and fundamental parameters suggest that it is in an advanced stage of internal dynamical evolution , possibly in the phase typical of those with mass segregation in their core regions .
However , the cluster still keeps its mass function close to that of the Salpeter ’ s law .