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 Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We simulate mergers between galaxies containing collisionally-relaxed nucleiaround massive black holes (MBHs). Our galaxies contain four mass groups,representative of old stellar populations; a primary goal is to understand thedistribution of stellar-mass black holes (BHs) after the merger. Mergers arefollowed using direct-summation N-body simulations, assuming a mass ratio of1:3 and two different orbits. Evolution of the binary MBH is followed until itsseparation has shrunk by a factor of 20 below the hard-binary separation.During the galaxy merger, large cores are carved out in the stellardistribution, with radii several times the influence radius of the massivebinary. Much of the pre-existing mass segregation is erased during this phase.We follow the evolution of the merged galaxies for approximately three, centralrelaxation times after coalescence of the massive binary; both standard, andtop-heavy, mass functions are considered. The cores that were formed in thestellar distribution persist, and the distribution of the stellar-mass blackholes evolves against this essentially fixed background. Even after one centralrelaxation time, these models look very different from the relaxed, multi-massmodels that are often assumed to describe the distribution of stars and stellarremnants near a massive BH. While the stellar BHs do form a cusp on roughly arelaxation time-scale, the BH density can be much smaller than in those models.We discuss the implications of our results for the EMRI problem and for theexistence of Bahcall-Wolf cusps.

Long-term evolution of massive black hole binaries. IV. Mergers of galaxies with collisionally relaxed nuclei