Ionized gas kinematics of massive elliptical galaxies in CALIFA and in cosmological zoom-in simulations

Abstract

Context. Powerful Active Galactic Nuclei (AGN) are supposed to play a key regulatory role on the evolution of their host galaxies by shaping the thermodynamic properties of their gas component. However, little is known as to the nature and the visibility timescale of the kinematical imprints of AGN-driven feedback. Gaining theoretical and observational insights into this subject is indispensable for a thorough understanding of the AGN-galaxy co-evolution and could yield empirical diagnostics for the identification of galaxies that have experienced a major AGN episode in the past. Aims. We present an investigation of kinematical imprints of AGN feedback on the Warm Ionized gas Medium (WIM) of massive early-type galaxies (ETGs). To this end, we take a two-fold approach that involves a comparative analysis of Hα velocity fields in 123 local ETGs from the CALIFA integral field spectroscopy survey with 20 simulated galaxies from high-resolution hydrodynamic cosmological SPHgal simulations. The latter were re-simulated for two modeling setups, one with and another without AGN feedback. Methods. In order to quantify the effects of AGN feedback on gas kinematics we measure three parameters that probe deviations from simple regular rotation using the kinemetry package. These indicators trace the possible presence of distinct kinematic components in Fourier space (k3,5/k1), variations in the radial profile of the kinematic major axis (σPA), and offsets between the stellar and gas velocity fields (∆φ). These quantities are monitored in the simulations from a redshift 3 to 0.2 to assess the connection between black hole accretion history, stellar mass growth and kinematical perturbation of the WIM. Results. Observed local massive galaxies show a broad range of irregularities, indicating disturbed warm gas motions, irrespective of being classified via diagnostic lines as AGN or not. Simulations of massive galaxies with AGN feedback generally exhibit higher irregularity parameters than without AGN feedback, more consistent with observations. Besides AGN feedback, other processes like major merger events or infalling gas clouds can lead to elevated irregularity parameters, but they are typically of shorter duration. More specifically, k3,5/k1 is most sensitive to AGN feedback, whereas ∆φ is most strongly affected by gas infall. Conclusions. We conclude that even if the general disturbance of the WIM velocity is not a unique indicator for AGN feedback, irregularity parameters, high enough to be consistent with observations, can only be reproduced in simulations with AGN feedback. Specifically, an elevated value for the deviation from simple ordered motion is a strong sign for previous events of AGN activity and feedback.

Self-consistent population spectral synthesis with FADO

“…In the construction of the models, we did not take into account potential misalignments of stellar and gas kinematics. Decoupling of gas and stars in a galaxy can be indicative of gas accretion (Sarzi et al 2007;Chen et al 2019), AGN or starburst-driven feedback (Florian et al 2020;Cicone et al 2016), and/or gas loss due to environmental effects (Duckworth et al 2020). The misalignment affects mainly early-type galaxies and only a small fraction of star-forming discs (Jin et al 2016).…”

The MAGPI survey: Drivers of kinematic asymmetries in the ionised gas ofz∼ 0.3 star-forming galaxies

“…They are, however, consistent with findings in HI-SAMI where there was a lack of a connection between the asymmetry measured from HI global flux distributions (which primarily traces asymmetries at larger radial extents) and the more centrally concentrated ionised gas which come from AGN (Watts et al 2023a). The impact of AGN have on velocity maps in simulated galaxies has shown that those with AGN demonstrated larger asymmetries, and that velocity maps of simulated galaxies where AGN feedback was not implemented were inconsistent with the asymmetric AGN galaxies in CALIFA (Florian et al 2020).…”

“…In the last decade, IFS surveys (e.g., SINS; Förster Schreiber et al 2006, ATLAS 3D ;Cappellari et al 2011, SAMI;Bryant et al 2015, MaNGA;Bundy et al 2015, CALIFA;Sánchez et al 2016) have revealed the wide range of complex kinematic features and the disturbed kinematics that galaxies can display. These disturbances have been linked to external processes such as gas stripping and mergers (e.g., Bellhouse et al 2017;Bloom et al 2018;Feng et al 2020;Ristea et al 2022), and internal processes such as star-formation, torques provided from a bar or the presence of an AGN (e.g., Barrera-Ballesteros et al 2014;Holmes et al 2015;Bloom et al 2017a;Florian et al 2020).…”

Self-consistent population spectral synthesis with FADO: II. Star formation history of galaxies in spectral synthesis methods

“…In the construction of the models, we did not take into account potential misalignments of stellar and gas kinematics. Decoupling of gas and stars in a galaxy can be indicative of gas accretion (Sarzi et al 2007;Chen et al 2019), AGN or starburstdriven feedback (Florian et al 2020;Cicone et al 2016), and/or gas loss due to environmental effects (Duckworth et al 2020). The misalignment affects mainly early-type galaxies and only a small fraction of star-forming discs (Jin et al 2016).…”