English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We perform dry merger simulations to investigate the role of dry mergers inthe size growth of early-type galaxies in high density environments. We replacethe virialized dark matter haloes obtained by a large cosmological $N$-bodysimulation with $N$-body galaxy models consisting of two components, a stellarbulge and a dark matter halo, which have higher mass resolution than thecosmological simulation. We then re-simulate nine cluster forming regions,whose masses range from 1e+14 Msun to 5e+14 Msun. Masses and sizes of stellarbulges are also assumed to satisfy the stellar mass--size relation of high-zcompact massive early-type galaxies. We find that dry major mergersconsiderably contribute to the mass and size growth of central massivegalaxies. One or two dry major mergers double the average stellar mass andquadruple the average size between $z=2$ and $z=0$. These growths favorablyagree with observations. Moreover, the density distributions of our simulatedcentral massive galaxies grow from the inside-out, which is consistent withrecent observations. The mass--size evolution is approximated as R proptoM_{*}^{alpha}, with alpha ~ 2.24. Most of our simulated galaxies areefficiently grown by dry mergers, and their stellar mass--size relations matchthe ones observed in the local Universe. Our results show that the centralgalaxies in the cluster haloes are potential descendants of high-z (z ~ 2-3)compact massive early-type galaxies. This conclusion is consistent withprevious numerical studies which investigate the formation and evolution ofcompact massive early-type galaxies.

Mass and size growth of early-type galaxies by dry mergers in cluster environments