We derive NUV luminosity functions for 6471 NUV detected galaxies in 28 0.02 < z < 0.08 clusters and consider their dependence on cluster properties .
We consider optically red and blue galaxies and explore how their NUV LFs vary in several cluster subsamples , selected to best show the influence of environment .
Our composite LF is well fit by the Schechter form with M ^ { * } _ { NUV } = -18.98 \pm 0.07 and \alpha = -1.87 \pm 0.03 in good agreement with values for the Coma centre and the Shapley supercluster , but with a steeper slope and brighter L ^ { * } than in Virgo .
The steep slope is due to the contribution of massive quiescent galaxies that are faint in the NUV .
There are significant differences in the NUV LFs for clusters having low and high X-ray luminosities and for sparse and dense clusters , though none are particularly well fitted by the Schechter form , making a physical interpretation of the parameters difficult .
When splitting clusters into two subsamples by X-ray luminosity , the ratio of low to high NUV luminosity galaxies is higher in the high X-ray luminosity subsample ( i.e the luminosity function is steeper across the sampled luminosity range ) .
In subsamples split by surface density , when characterised by Schechter functions the dense clusters have an M ^ { * } about a magnitude fainter than that of the sparse clusters and \alpha is steeper ( -1.9 vs . -1.6 respectively ) .
The differences in the data appear to be driven by changes in the LF of blue ( star-forming ) galaxies .
This appears to be related to interactions with the cluster gas .
For the blue galaxies alone , the luminosity distributions indicate that for high L _ { X } and high velocity dispersion cluster subsamples ( i.e .
the higher mass clusters ) , there are relatively fewer high UV luminosity galaxies ( or correspondingly a relative excess of low UV luminosity galaxies ) in comparison the lower mass cluster subsamples .