We present Gemini-North GMOS/IFU observations of a young star cluster and its environment near the centre of the dwarf irregular starburst galaxy NGC 1569 .
This forms part of a larger and on-going study of the formation and collimation mechanisms of galactic winds , including three additional IFU pointings in NGC 1569 covering the base of the galactic wind which are analysed in a companion paper .
The good spatial- and spectral-resolution of these GMOS/IFU observations , covering 4740–6860 Å , allow us to probe the interactions between clusters and their environments on small scales .
For cluster 10 , we combine the GMOS spectrum with HST imaging to derive its properties .
We find that it is composed of two very close components with ages of 5–7 Myr and \leq 5 Myr , and a combined mass of 7 \pm 5 \times 10 ^ { 3 } M _ { \odot } .
A strong red Wolf-Rayet ( WR ) emission feature confirms our young derived cluster ages .

A detailed analysis of the H \alpha emission line profile shapes across the whole field-of-view shows them to be composed of a bright narrow feature ( intrinsic FWHM \sim 50 km s ^ { -1 } ) superimposed on a fainter broad component ( FWHM \leq 300 km s ^ { -1 } ) .
By mapping the properties of each individual component , we investigate the small-scale structure and properties of the ionized ISM , including reddening , excitation and electron densities , and for the first time find spatial correlations between the line component properties .
We discuss in detail the possible mechanisms that could give rise to the two components and these correlations , and conclude that the most likely explanation for the broad emission is that it is produced in a turbulent mixing layer on the surface of the cool gas clumps embedded within the hot , fast-flowing cluster winds .
We discuss implications for the mass-loading of the flow under these circumstances .
The average radial velocity difference between the narrow and broad components is small compared to the line widths , implying that within the IFU field-of-view , turbulent motions dominate over large-scale bulk motions .
We are therefore sampling well within the outer bounding shocks of the expanding superbubbles and within the outflow ‘ energy injection zone ’ .