We combine an N-body simulation algorithm with a subgrid treatment of galaxy formation, mergers, and tidal destruction, and an observed conditional luminosity function Φ(L|M), to study the origin and evolution of galactic and extragalactic light inside a cosmological volume of size (100 Mpc)3, in a concordance ΛCDM model. This algorithm simulates the growth of large-scale structures and the formation of clusters, the evolution of the galaxy population in clusters, the destruction of galaxies by mergers and tides, and the evolution of the intracluster light (ICL). We find that destruction of galaxies by mergers dominates over destruction by tides by about an order of magnitude at all redshifts. However, tidal destruction is sufficient to produce ICL fractions f ICL that are sufficiently high to match observations. Our simulation produces 18 massive clusters (M cl 1014 M ☉) with values of f ICL ranging from 1% to 58% at z = 0. There is a weak trend of f ICL to increase with cluster mass. The bulk of the ICL (~60%) is provided by intermediate galaxies of total masses 1011-1012 M ☉ and stellar masses 6 × 108 M ☉ to 3 × 1010 M ☉ that were tidally destroyed by even more massive galaxies. The contribution of low-mass galaxies to the ICL is small and the contribution of dwarf galaxies is negligible, even though, by numbers, most galaxies that are tidally destroyed are dwarfs. Tracking clusters back in time, we find that their values of f ICL tend to increase over time, but can experience sudden changes that are sometimes non-monotonic. These changes occur during major mergers involving clusters of comparable masses but very different intracluster luminosities. Most of the tidal destruction events take place in the central regions of clusters. As a result, the ICL is more centrally concentrated than the galactic light. Our results support tidal destruction of intermediate-mass galaxies as a plausible scenario for the origin of the ICL.
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机译：我们将N体模拟算法与银河形成，合并和潮汐破坏的亚网格处理以及观察到的条件光度函数Φ（L | M）相结合，以研究宇宙空间内银河和银河外光的起源和演化尺寸（100 Mpc）3，符合ΛCDM模型。该算法模拟大型结构的增长和星团的形成，星团中星系种群的演化，合并和潮汐对星系的破坏以及团簇内光（ICL）的演化。我们发现，在所有红移中，合并对星系的破坏要比潮汐对破坏的影响大一个数量级。但是，潮汐破坏足以产生ICL分数，足以满足观测结果。我们的模拟产生了18个大簇（M cl> 1014 M☉），在z = 0时，f ICL的值在1％到58％之间。随着团簇质量的增加，f ICL的趋势很弱。 ICL的大部分（〜60％）是由总质量1011-1012 M intermediate的中间星系和6×108 M☉至3×1010 M st的恒星质量提供的，这些潮汐质量甚至被更大质量的星系消灭了。低质量星系对ICL的贡献很小，而矮星系的贡献可以忽略不计，尽管从数量上看，大多数被潮汐破坏的星系是矮星。追溯群集，我们发现它们的f ICL值会随着时间的推移而增加，但是会遇到有时是非单调的突然变化。这些变化发生在大型合并中，这些合并涉及质量相当但群集内亮度差异很大的群集。大多数潮汐破坏事件发生在星团的中心区域。结果，ICL比银河灯更集中地集中。我们的结果支持潮汐破坏中间质量星系，这是ICL起源的一个合理的情况。
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