| Abstract : | The very central regions of galaxies harbour two types of known compact massive objects, namely massive black holes (MBHs) and/or nuclear star clusters (NSCs). Both NSCs and MBHs hold very similar scaling relations with host galaxy properties. In an attempt to understand whether NSCs are an essential ingredient or an intermediate step towards the formation of a supermassive black hole in the galaxy nucleus, we examine the centres of nearby (< 44 Mpc) early-type galaxies hosting NSCs with the photometric tool central intensity ratio (CIR; Aswathy & Ravikumar 2018, 2020, Sruthi & Ravikumar 2021) using Spitzer space Telescope’s 3.6µm observations. CIR measured in the infra-red band (CIR_I) of the sample shows significant positive correlations with different host-galaxy properties including mass of central BH and reflect the possible connection between the growth of galaxies and their central light distribution. Comparison of more evolved early-type galaxies propose co-evolution of NSCs and central BHs such that NSCs grow with BHs initially, while, presence of super-massive black holes seem to suppress growth of NSCs. |
