NGC 5128, J.L. Sersic, Atlas de Galaxias Australes, 1968
NGC 253, J.L. Sersic, Atlas de Galaxias Australes, 1968
1st Extragalactic Astronomy Meeting, 1975, J.L. Sersic, T.G. Catellanos, P. Kaufman
NGC 2442, J.L. Sersic, Atlas de Galaxias Australes, 1968
2nd Extragalactic Astronomy Meeting, 1987
NGC 2997, J.L. Sersic, Atlas de Galaxias Australes, 1968
3rd Extragalactic Astronomy Meeting, 1996
NGC 55, J.L. Sersic, Atlas de Galaxias Australes, 1968

Montenegro Taborda Daniel Esteban

Mexico –  Instituto de Radioastronomía y Astrofísica

The growth of brightest cluster galaxies in the TNG300 simulation: dissecting the contributions from mergers and in situ star formation.

 I will present the results of our recent manuscript (Montenegro-Taborda et al. 2023, MNRAS, 521, 800) where we investigate the properties of brightest cluster galaxies (BCGs) in the TNG300 cosmological simulation of the IllustrisTNG project, to better understand their formation mechanisms. We find that the stellar masses and star formation rates of our simulated BCGs are in good agreement with observations at z≲0.4, and that they have experienced, on average, ∼2 (∼3) major mergers since z=1 (z=2). Separating the BCG from the intracluster light (ICL), we find that the fraction of stellar mass contributed by ex situ (i.e. accreted) stars at z=0 is approximately 70, 80, and 90 per cent of the BCG, BCG+ICL, and ICL, respectively. Tracking the simulated BCGs back in time using the merger trees, we find that they became dominated by ex situ stars at z∼1–2, and that half of the stars that are part of the BCG at z=0 formed early (z∼3) in other galaxies. Finally, I will show that the stellar mass profiles of BCGs are often dominated by ex situ stars at all radii, with stars from major mergers being found closer to the centre, while stars that were tidally stripped from other galaxies dominate the outer regions.

PROGRAM