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

In this work, we analyze a sample of $\sim$4000 massive ($M_*\geq 10^{11}M_\odot$ at $z=0$) galaxies in TNG300, the $(300 \mathrm{Mpc})^3$ box of theIllustrisTNG simulation suite. We characterize the shape and kinematics ofthese galaxies with a focus on the kinematic misalignment ($\Psi_\mathrm{int}$)between the angular momentum (AM) and morphological major axis. We find thatthe traditional purely shape- or kinematics-based classifications areinsufficient to characterize the diversity of our sample and define a new setof classes based on the rates of change of the galaxies' morphological andkinematic axes. We show that these classes are mostly stable over time andcorrespond to six distinct populations of galaxies: the rapid AM reorienters(58% of our sample), unsettled galaxies (10%), spinning disks (10%), twirlingcigars (16%), misaligned slow reorienters (3%), and regular prolate rotators(galaxies that display major axis rotation; 2%). We demonstrate that themost-recent significant (mass-ratio $\mu>1/10$) mergers of these galaxies arethe primary cause for their present-day properties and find that these mergersare best characterized at the point of the satellite's final infall -- that is,much closer to the final coalescence than has been previously thought. We showthat regular prolate rotators evolve from spinning disk progenitors thatexperience a radial merger along their internal AM direction. Finally, we arguethat these regular prolate rotators are distinct from the similarly-sizedpopulation of rapid AM reorienters with large $\Psi_\mathrm{int}$, implyingthat a large $\Psi_\mathrm{int}$ is not a sufficient condition for major axisrotation.

Reorientation Rates of Structural and Kinematic Axes in Simulated Massive Galaxies and the Origins of Prolate Rotation