We analyse multi-wavelength Hubble Space Telescope ( HST ) observations of a large number of star clusters in the nearby ( post- ) starburst dwarf galaxy NGC 1569 .
Their spectral energy distributions ( SEDs ) cover at least the wavelength range from U to I in equivalent HST filters , in most cases supplemented by near-infrared data .
Using our most up-to-date evolutionary synthesis models of the Göttingen galev code we determine ages , metallicities , extinction values and masses for each individual cluster robustly and independently .
We confirm the youth of most of these objects .
The majority were formed in a very intense starburst starting around 25 Myr ago .
While there are two prominent “ super star clusters ” present in this galaxy , with masses of ( 5 - 16 ) \times 10 ^ { 5 } ~ { } M _ { \odot } , almost all remaining clusters are significantly less massive than an average Milky Way globular cluster , and are generally consistent with open cluster-type objects .
We determine the cluster mass function from individual cluster masses derived by scaling the model SEDs of known mass to the observed cluster SEDs for each individual cluster .
We find signs of a change in the cluster mass function as the burst proceeds , which we attribute to the special conditions of star cluster formation in this starburst dwarf galaxy environment .