The impact of AGN on stellar kinematics and orbits in simulated massive galaxies

Matteo Frigo, Thorsten Naab, Michaela Hirschmann, Ena Choi, Rachel S. Somerville, Davor Krajnovic, Romeel Dave, Michele Cappellari

Research output: Contribution to journalArticlepeer-review

18 Scopus citations


We present a series of 10 × 2 cosmological zoom simulations of the formation of massive galaxies with and without a model for active galactic nucleus (AGN) feedback. Differences in stellar population and kinematic properties are evaluated by constructing mock integral field unit maps. The impact of the AGN is weak at high redshift when all systems are mostly fast rotating and disc-like. After z ∼ 1 the AGN simulations result in lower mass, older, less metal rich, and slower rotating systems with less discy isophotes - in general agreement with observations. 2D kinematic maps of in situ and accreted stars show that these differences result from reduced in-situ star formation due to AGN feedback. A full analysis of stellar orbits indicates that galaxies simulated with AGN are typically more triaxial and have higher fractions of x-tubes and box orbits and lower fractions of z-tubes. This trend can also be explained by reduced late in-situ star formation. We introduce a global parameter, ξ 3, to characterize the anticorrelation between the third-order kinematic moment h3 and the lineof- sight velocity (Vavg/σ), and compare to ATLAS3D observations. The kinematic correlation parameter ξ 3 might be a useful diagnostic for large integral field surveys as it is a kinematic indicator for intrinsic shape and orbital content.

Original languageEnglish
Pages (from-to)2702-2722
Number of pages21
JournalMonthly Notices of the Royal Astronomical Society
Issue number2
StatePublished - 21 Oct 2019


  • Galaxies: Evolution
  • Galaxies: Formation
  • Galaxies: Kinematics and dynamics
  • Methods: numerical


Dive into the research topics of 'The impact of AGN on stellar kinematics and orbits in simulated massive galaxies'. Together they form a unique fingerprint.

Cite this