The Next Generation Fornax Survey (NGFS): IV. Mass and Age Bimodality of Nuclear Clusters in the Fornax Core Region

Understand

We present the analysis of 61 nucleated dwarf galaxies in the central regions ($<R_{\rm vir}/4$) of the Fornax galaxy cluster.

• The galaxies and their nuclei are studied as part of the Next Generation Fornax Survey (NGFS) using optical imaging obtained with the Dark Energy Camera (DECam) mounted at Blanco/CTIO and near-infrared data obtained with VIRCam at VISTA/ESO.
• We decompose the nucleated dwarfs in nucleus and spheroid, after subtracting the surface brightness profile of the spheroid component and studying the nucleus using PSF photometry.In general, nuclei are consistent with colors of confirmed metal-poor globular clusters, but with significantly smaller dispersion than other confirmed compact stellar systems in Fornax.
• We find a bimodal nucleus mass distribution with peaks located at $\log({\cal M_*}/M_\odot)\!\simeq\!5.4$ and $\sim\,6.3$.