Paola Oliva-Altamirano edited untitled.tex  almost 9 years ago

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Sarah~Brough, \textit{Sarah Brough,  Jimmy, Kim-Vy~Tran, Warrick~J.~Couch, Richard~M.~McDermid, Chris~Lidman, Anja~von~der~Linden,Rob~Sharp Kim-Vy Tran, Warrick J. Couch, Richard M. McDermid, Chris Lidman, Anja von der Linden, Rob Sharp}  \\ \begin{abstract}  We analyse the spatially-resolved stellar populations of 9 local ($z<0.1$) Brightest Cluster Galaxies (BCGs) observed with VIMOS in IFU mode. Our sample is composed of 7 slow-rotating and 2 fast-rotating BCGs. We do not find a connection between stellar kinematics and stellar populations in this small sample. The BCGs have shallow metallicity gradients (median $\Delta$[Fe/H]~$= -0.11\pm0.1$), high central metallicities (median $[$Fe/H$]_{[\alpha/Fe]=0}= 0.13\pm0.07$), and a wide range of central ages (from 5 to 15~Gyr). We propose that the reason for this is diverse evolutionary paths in BCGs. 67 per cent of the sample (6/9) show $\sim 7$~Gyr old central ages, which reflects an active accretion history, and 33 per cent of the sample (3/9) have central ages older than 11 Gyr, which suggest no star formation since $z=2$. The BCGs show similar central stellar populations and stellar population gradients to early-type galaxies of similar mass (M$_{dyn}> 10^{11.3}$M$_{\odot}$) from the ATLAS$^{3D}$ survey (median [Z/H]~$= 0.04\pm0.07$, $\Delta$[Z/H]~$= -0.19\pm0.1$). However, massive early-type galaxies from ATLAS$^{3D}$ have consistently old ages (median Age~$=12.0\pm3.8$~Gyr). We also analyse the close massive companion galaxies of two of the BCGs. These galaxies have similar stellar populations to their respective BCGs.  \end{abstract}