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arXiv · 2312.05532

Deep imaging with Milankovi\'c telescope: Linking merger history to kinematics of elliptical galaxies

Ivana Ebrová·Michal Bílek·Ana Lalović·Mustafa K. Yıldız·Pierre-Alain Duc·Martin Mašek·Michael Prouza
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Abstract

Kinematical and morphological features observed in early-type galaxies provide valuable insights into the evolution of their hosts. We studied the origin of prolate rotation (i.e., rotation around the long axis) in Illustris large-scale cosmological hydrodynamical simulations. We found that basically all the simulated massive prolate rotators were created in relatively recent major mergers of galaxies. Such mergers are expected to produce tidal features such as tails, shells, asymmetric stellar halos. We investigated deep optical images of prolate rotators, including newly obtained Milankovi\'c data, revealing signs of galaxy interaction in all of them. This correlation proves to be statistically very significant when compared with a general sample of early-type galaxies from the MATLAS deep imaging survey. In an ongoing project, we use Milankovi\'c to assemble deep images of the complete sample of all known nearby massive prolate rotators. Additionally, we searched these data for asteroids to improve the accuracy of trajectories and even discover one previously unknown main-belt asteroid. The most frequent tidal features among the prolate rotators happen to be shells. We developed methods to calculate the probable time of the merger from optical images. This will allow us to compare the merger history of the sample with predictions from Illustris. Our plan is to expand these methods to even larger samples of shell galaxies supplied by upcoming large surveys like LSST at Rubin Observatory. This will provide an unprecedented amount of statistically significant data on the recent merger history of our Universe and allow extensive investigation of the impact of mergers to a wide range of other astrophysical phenomena.

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Ivana Ebrová, Michal Bílek, Ana Lalović, Mustafa K. Yıldız, Pierre-Alain Duc, Martin Mašek, Michael Prouza. 2023-12-09. Deep imaging with Milankovi\'c telescope: Linking merger history to kinematics of elliptical galaxies. https://arxiv.org/abs/2312.05532

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