"Do Galaxy Mergers Increase Star Formation and Turbulence at Cosmic Noon?"
ESO Galaxy Evolution Coffee
- Datum: 30.04.2026
- Uhrzeit: 10:00 - 10:30
- Vortragende(r): Isaac Kanowski (Australian National University)
- Ort: ESO Garching
- Raum: Library
Abstract:
Mergers and interactions are important events in galaxy evolution, and have been shown to enhance star formation rates, decrease metallicities, and disrupt kinematics. Observations in the local universe and galaxy simulations across cosmic time suggest that mergers can also increase turbulence. However, observational studies of interaction-driven turbulence at z > 1 are limited, as kinematic measurements of interactions have been inhibited by beam smearing.
In this talk I will present a systematic observational study quantifying the impact of interactions on galaxy turbulence at cosmic noon (z ~ 1-3). We leverage a spatially non-parametric kinematic deconvolution code to account for beam smearing and apply it to integral field spectroscopic observations of ionised gas from the KMOS3D survey. We compare deconvolved velocity dispersions of interacting galaxies to mass- and lookback-time-matched isolated galaxies. Despite finding increased star formation in interacting galaxies, we find no increase in galaxy-scale velocity dispersions.
Our findings put constraints on the level of interaction-driven turbulence at cosmic noon. I will also discuss our results on the relative increase in SFR of interacting pairs in the context of other merger samples across cosmic time.
Mergers and interactions are important events in galaxy evolution, and have been shown to enhance star formation rates, decrease metallicities, and disrupt kinematics. Observations in the local universe and galaxy simulations across cosmic time suggest that mergers can also increase turbulence. However, observational studies of interaction-driven turbulence at z > 1 are limited, as kinematic measurements of interactions have been inhibited by beam smearing.
In this talk I will present a systematic observational study quantifying the impact of interactions on galaxy turbulence at cosmic noon (z ~ 1-3). We leverage a spatially non-parametric kinematic deconvolution code to account for beam smearing and apply it to integral field spectroscopic observations of ionised gas from the KMOS3D survey. We compare deconvolved velocity dispersions of interacting galaxies to mass- and lookback-time-matched isolated galaxies. Despite finding increased star formation in interacting galaxies, we find no increase in galaxy-scale velocity dispersions.
Our findings put constraints on the level of interaction-driven turbulence at cosmic noon. I will also discuss our results on the relative increase in SFR of interacting pairs in the context of other merger samples across cosmic time.