# The fate of the Antennae galaxies

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http://hdl.handle.net/10138/309984

#### Citation

Lahén , N , Johansson , P H , Rantala , A , Naab , T & Frigo , M 2018 , ' The fate of the Antennae galaxies ' , Monthly Notices of the Royal Astronomical Society , vol. 475 , no. 3 , pp. 3934-3958 . https://doi.org/10.1093/mnras/sty060-

 Title: The fate of the Antennae galaxies Author: Lahén, Natalia; Johansson, Peter H.; Rantala, Antti; Naab, Thorsten; Frigo, Matteo Other contributor: University of Helsinki, Department of Physics University of Helsinki, Department of Physics University of Helsinki, Department of Physics Date: 2018-04 Language: eng Number of pages: 25 Belongs to series: Monthly Notices of the Royal Astronomical Society ISSN: 0035-8711 DOI: https://doi.org/10.1093/mnras/sty060- URI: http://hdl.handle.net/10138/309984 Abstract: We present a high-resolution smoothed particle hydrodynamics simulation of the Antennae galaxies (NGC 4038/4039) and follow the evolution $3$ Gyrs beyond the final coalescence. The simulation includes metallicity dependent cooling, star formation, and both stellar feedback and chemical enrichment. The simulated best-match Antennae reproduces well both the observed morphology and the off-nuclear starburst. We also produce for the first time a simulated two-dimensional metallicity map of the Antennae and find good agreement with the observed metallicity of off-nuclear stellar clusters, however the nuclear metallicities are overproduced by $\sim 0.5$ dex. Using the radiative transfer code SKIRT we produce multi-wavelength observations of both the Antennae and the merger remnant. The $1$ Gyr old remnant is well fitted with a S\'ersic profile of $n=4.05$, and with an $r$-band effective radius of $r_{\mathrm{e}}= 1.8$ kpc and velocity dispersion of $\sigma_{\mathrm{e}}=180$ km$/$s the remnant is located on the fundamental plane of early-type galaxies (ETGs). The initially blue Antennae remnant evolves onto the red sequence after $\sim 2.5$ Gyr of secular evolution. The remnant would be classified as a fast rotator, as the specific angular momentum evolves from $\lambda_R\approx0.11$ to $\lambda_R\approx0.14$ during its evolution. The remnant shows ordered rotation and a double peaked maximum in the mean 2D line-of-sight velocity. These kinematical features are relatively common among local ETGs and we specifically identify three local ETGs (NGC 3226, NGC 3379 and NGC 4494) in the ATLAS$^\mathrm{3D}$ sample, whose photometric and kinematic properties most resemble the Antennae remnant. Subject: astro-ph.GA RADIATIVE-TRANSFER CODE galaxies: starburst ELLIPTIC GALAXIES galaxies: evolution H-II REGIONS methods: numerical SMOOTHED PARTICLE HYDRODYNAMICS galaxies: individual: NGC 4038/4039 MASS-METALLICITY RELATION YOUNG STAR-CLUSTERS TO-LIGHT RATIO DIGITAL SKY SURVEY galaxies: kinematics and dynamics LENS ACS SURVEY ULTRALUMINOUS INFRARED GALAXIES 115 Astronomy, Space science Rights:
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