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Title: Formation and evolution of young massive clusters in galaxy mergers: the SMUGGLE view
ABSTRACT Galaxy mergers are known to host abundant young massive cluster (YMC) populations, whose formation mechanism is still not well-understood. Here, we present a high-resolution galaxy merger simulation with explicit star formation and stellar feedback prescriptions to investigate how mergers affect the properties of the interstellar medium and YMCs. Compared with a controlled simulation of an isolated galaxy, the mass fraction of dense and high-pressure gas is much higher in mergers. Consequently, the mass function of both molecular clouds and YMCs becomes shallower and extends to higher masses. Moreover, cluster formation efficiency is significantly enhanced and correlates positively with the star formation rate surface density and gas pressure. We track the orbits of YMCs and investigate the time evolution of tidal fields during the course of the merger. At an early stage of the merger, the tidal field strength correlates positively with YMC mass, λtid ∝ M0.71, which systematically affects the shape of the mass function and age distribution of the YMCs. At later times, most YMCs closely follow the orbits of their host galaxies, gradually sinking into the centre of the merger remnant due to dynamical friction, and are quickly dissolved via efficient tidal disruption. Interestingly, YMCs formed during the first more » passage, mostly in tidal tails and bridges, are distributed over a wide range of galactocentric radii, greatly increasing their survivability because of the much weaker tidal field in the outskirts of the merger system. These YMCs are promising candidates for globular clusters that survive to the present day. « less
Authors:
; ; ; ; ;
Award ID(s):
1945310 2008490 2108470 1814259 1909831 2107724 2007355 1909933
Publication Date:
NSF-PAR ID:
10333316
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
514
Issue:
1
Page Range or eLocation-ID:
265 to 279
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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