Galaxy clusters are the most massive gravitationally bound structures in the Universe. They can be used both as cosmological probes and as laboratories for testing theories of galaxy formation and evolution. This thesis presents a study of the assembly of stellar mass in galaxy cluster cores between redshift z = 1 and the present, focusing principally on brightest cluster galaxies (BeGs) and the intracluster light (ICL). First, the growth of BeGs is examined through the evolution of their half-light radii using rest-frame matched samples of galaxy clusters at redshifts z = 1 and z = 0.23. A critical analysis of the methods available to measure half-light radius is presented, then the size evolution of the BeGs is measured through the parameterisation of their surface brightness profiles. Using a surface brightness profile fit of fixed slope, the half-light radii of BCGs are found on average to increase by 53% in the 5 Gyr between z = 1 and z = 0.23. This result is in stark contrast to recent findings for the size growth of field ellipticals, which are found. to increase in radius by 2-5 times between 0 < z < 2. It is concluded that the dense environments which BCGs occupy has allowed them to rapidly assemble the majority of their stellar masses early in the Universe, making them almost fully mature by z = I, whereas field ellipticals undergo a slower assembly. Secondly, the first ever measurement of the intracluster light in galaxy clusters at z = 1 is presented. The ICL is detected with near-infrared data from HAWK-/ on the Very Large Telescope and is measured using a simple surface brightness thresholding technique. Below a surface brightness threshold of J.J..J = 22 maglarcsec2 the ICL is found to contain -4% of the total cluster light at z = 1, a fraction which must increase substantially when compared with nearby galaxy clusters
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:590130 |
| Date | January 2013 |
| Creators | Burke, Claire |
| Publisher | Liverpool John Moores University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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