The thermodynamic properties of the ionized baryons in galaxies, groups, and clusters encode the effects of the assembly history and feedback processes that shape galaxy and cluster formation. These properties can be studied through the thermal and kinematic Sunyaev-Zel’dovich (SZ) effects imprinted on high resolution maps of the cosmic microwave background (CMB). I will review new SZ observations (Schaan, Ferraro, Amodeo et al. 2021) from the Atacama Cosmology Telescope DR5 and Planck in combination with the CMASS galaxy catalogs from the Baryon Oscillation Spectroscopic Survey, from which we achieve high signal-to-noise measurements of the electron density, temperature and pressure distribution around the CMASS galaxies. I will discuss new constraints on the feedback and the non-thermal pressure support, as well as the effect of including baryons in the modeling of galaxy-galaxy lensing measurements (Amodeo et al. 2021). These measurements provide novel tests of current and future hydrodynamical simulations with sub-grid physics models. I will outline the rapid growth of SZ cross-correlation measurements expected over the next decade with upcoming CMB experiments, like Simons Observatory and CMB-S4, and large-scale structure surveys like DESI, the Rubin Observatory or Euclid.

The Athena/X-IFU instrument will deliver X-ray spectroscopy data with an unprecedent spatial and spectral resolution. Those capabilities will enable studies beyond the reach of the current and upcoming generations of X-ray spectrometers. With X-IFU spatially resolved high resolution spectroscopy we will look into the assembly of the matter largest halos, groups and clusters of galaxies. In this work we focus on the ability of the X-IFU to characterize bulk and turbulence motions in the intra-cluster medium (ICM). Those are induced by various processes such as accretion, merger events, or AGN activities, and they are key to retrace the growth and evolution of groups and clusters of galaxies. We rely on diagnostics such as line shifts, line broadenings and structure functions. Using end-to-end mock X-IFU observations from a toy model galaxy cluster at z=0.1, we conduct a feasibility study on the abilities of the X-IFU to recover the physical properties of the turbulent cascade, and so the internal dynamics of the ICM. I will briefly introduce the X-IFU detection chain and show our current results on the measurement of ICM gas motions. I will discuss the optimization of the observing strategy toward that end.

The question of the DM content in SFGs often relies on either deep Integral Field Spectroscopy (IFS) data or stacking analyses.

Alternatively, one can use a 3D (parametric) modelling approach on the 3D data in order to measure accurately the rotation curves of SFGs in the outskirts.

Here, we combine the deepest (140hr) observations of z=1 SFGs in the 140hr MUSE eXtremely Deep Field with a 3D disc-halo decomposition performed on the nebular emission line of SFGs. The disc-halo decomposition includes a stellar, DM, gas and occasionally a bulge component. The DM component uses either a Navarro-Frenk-White (NFW) DM profile or a generalized alpha-beta-gamma generalized DM profile. We find that (i) the generalized DM profiles with cores are preferred for isolated galaxies, (ii) the DM fractions are high and (iii) are able to test the concentration-halo mass relation of DM halos. We will show how our results are in agreement with the recent results on this front. We will discuss the future prospect for DM studies with this 3D approach.

The most massive halos of matter in the Universe grow via accretion and merger events throughout cosmic times. These violent processes generate shocks at many scales and induce large scale bulk and turbulent motions. These inject kinetic energy at large scales, which is transported to the viscous dissipation scales, contributing to the overall heating and virialisation of the halo, and acting as a source of non-thermal pressure in the intra-cluster medium.  Characterizing the physical properties of these gas motions will help us to better understand the assembly of massive halos, hence the formation and the evolution of these large scale structures.  We aim at this characterization via the study of the statistics of the X-ray and SZ surface brightness fluctuations.  We based our work on three complementary samples observed in X by XMM-Newton and in SZ by Planck and/or ACT and NIKA2, covering a wide range of redshifts and dynamical states of clusters. We will present the results of our analysis for the low redshift XCOP sample. We will discuss the derived properties according to the dynamical state of our clusters, and the possibility of a self-similar behaviour on the basis of the reconstructed gas motions power-spectra.  We will introduce the extension of our current work to a larger sample.

Galaxies in clusters undergo several phenomena such as ram pressure stripping and tidal interactions, that can trigger or quench their star formation and, in some cases, lead to galaxies acquiring unusual shapes and long tails, such as jellyfish galaxies. A dynamical study of these objects shows that some are infalling galaxies, i.e. falling into the cluster for the first time from the cosmic web, and some are backsplash galaxies, that have already crossed the cluster and are falling back onto it after reaching a maximum distance. In an extended search for jellyfish galaxies in the redshift range between 0.2 and 0.9, our large spatial coverage and abundant sampling of spectroscopic redshifts in MACS J0717.5+3745 (MACS0717) has allowed us to pursue a detailed analysis of jellyfish galaxies in this cluster and its long filament, and to see how they are distributed spatially and dynamically. We will present these properties, together with their stellar properties derived by fitting their spectral energy distributions, and see how their dynamical properties can be linked to the cosmic web around this large structure.

Cold dark matter numerical simulations predict steep, 'cuspy' density profiles for dark matter halos, while observations favour shallower 'cores'. The introduction of baryonic physics in simulations alleviates this discrepancy, notably as feedback-driven outflow episodes contribute to expanding the dark matter distribution. I will present different theoretical models describing core formation in dark matter haloes. In the first one, small stochastic density fluctuations induced by stellar feedback in the interstellar medium dynamically heat up the halo, leading to the formation of a core. In the second one, sudden bulk outflows reorganise the halo mass distribution while it relaxes to a new equilibrium. In the third one, the combination of dynamical friction from incoming satellites with outflows speeds up core formation and enables the presence of cores early in the history of the universe. 

We examine how the mass assembly of central galaxies depends on their  location in the cosmic web. The HORIZON-AGN simulation is analysed at z=2 using the DISPERSE code to extract multi-scale cosmic filaments. We  find that the dependency of galaxy properties on large-scale environment is mostly inherited from the (large-scale) environmental dependency of  their host halo mass. When adopting a residual analysis that removes the  host halo mass effect, we detect a direct and non-negligible influence of cosmic filaments. Proximity to filaments enhances the build-up of stellar mass, a result in agreement with previous studies. However, our multi-scale analysis also reveals that, at the edge of filaments, star  formation is suppressed. In addition, we find clues for compaction of  the stellar distribution at close proximity to filaments. We suggest that gas transfer from the outside to the inside of the haloes (where galaxies reside) becomes less efficient closer to filaments, due to high angular momentum supply at the vorticity-rich edge of filaments. This quenching mechanism may partly explain the larger fraction of passive galaxies in filaments, as inferred from observations at lower redshifts.

I will kickstart the conference!

I will present an ongoing study of the impact of the environment on the morphological and kinematical properties of intermediate redshift galaxies (0.25 ≤ z ≤ 1.5) with the use of combined HST and MUSE data. We use the latest MUSE-GTO observations of 17 different fields in the COSMOS area from the MAGIC survey to build a sample of roughly 600 resolved galaxies, within target structures, as well as in their foreground and background, allowing to probe a variety of environments, with virial masses in the range 10^9 − 10^14 Msun.

We perform a multi-component decomposition from the HST images, and extract the ionised gas kinematics from the MUSE cubes using the [OII] doublet as a kinematical tracer. Taking into account prior information gathered from the morphological decomposition, we perform a mass modelling in order to extract the galaxies main kinematical parameters such as their circular velocity and baryon fraction.

Because we are analysing galaxies from the same MUSE and HST observations, with similar methodology and tools, we can perform a robust comparison of the dynamical properties of galaxies found in various types of environments. Specifically, we are able to probe into details how the environment may affect the evolution of galaxies just after the peak of star formation.

In this presentation, after describing the initial sample and the selection criteria we applied, I will describe the methodology used to extract the dynamical properties of galaxies, in particular how we use prior morphological information to constrain the kinematics of the baryons. Then, I will present our past (Abril-Melgarejo et al. 2021) and current results on various scaling relations such as the mass-size and Tully-Fisher relations and show how these scale with structures properties. I will finish by briefly mentioning current developments being made to improve even further our modelling and analysis, as well as discuss how these methods will benefit from future instruments on next generation telescopes such as ELT-HARMONI.

Baryonic processes like star formation and stellar feedback are highly debated topics in galaxy formation and are of paramount importance for dark matter phenomenology and detection. We aim at illustrating the uncertainties introduced by the baryonic physics in the dark matter distribution of a Milky Way sized halo. To this end, we study the dark matter halo's morphology, geometry and mass profile as well as its phase-space distribution in the high-resolution Mochima cosmological simulations (A Milky Way sized galaxy simulated 6 times with different subgrid prescriptions for the stellar formation and SN feedback). We find that the modifications of the gravitational potential induced by the presence of baryons affects the structure of the dark matter distributions, particularly, modifying the mass density profile and the velocity distribution. The uncertainties on those quantities impact directly the dark matter direct and indirect detection rates. As a consequence, and until subgrid physics are under control, predictions using cosmological simulations have to be taken with caution as the dark matter distribution reacts to the baryonic physics.

The SRG satellite was launched in July 2019, carrying on-board the new soft X-ray instrument eROSITA. The eROSITA All-Sky Survey (eRASS) is well underway, with three of its eight sky coverages already completed. Before the start of the survey, the ability of the satellite to map large areas and study large-scale structures was tested with several performance verification programs, most notably the 120 deg2 eROSITA Final Equatorial Depth Survey (eFEDS) and a 15 deg2 map of a nearby system of interacting clusters, meant to probe their large scale environment and trace filamentary emission. While waiting for the full release of the eROSITA performance verification results (this summer), I will review the early results obtained from these observations on superclusters and cosmic filaments.  

It is widely understood that massive galaxies use, throughout the Hubble time, only a small fraction of the baryons associated to their dark matter halos to form stars. Such low baryon-to-stars conversion efficiencies are expected in galaxy formation scenarios where merging and AGN feedback play key roles in regulating star formation in galaxies at the high-mass end. However, not all massive galaxies are quenched, especially in low density environments.

In this talk I will show how we can constrain the effect of merging and AGN feedback by measuring the baryon-to-stars conversion efficiencies in nearby massive galaxies using galaxy dynamics. For the first time, we determine the stellar-to-halo mass relation (SHMR) of both late-type and early-type galaxies from individual measurements of their halo masses, based on HI rotation curves for late types (Posti et al. 2019, A&A, 626, 56), and on the kinematics of their globular cluster systems for early types (Posti & Fall 2021, A&A in press). While the SHMR for early types peaks at about the Milky Way mass and then declines with mass - consistent with abundance matching of the general population of galaxies - the SHMR for late types monotonically rises with mass, with no sign of a turnover. Our results demonstrate that the SHMR for massive galaxies varies continuously, from rising to falling, with decreasing bulge fraction.

I will discuss the repercussions of these findings in our understanding of the evolution of massive galaxies. All these empirical findings are natural consequences of a picture in which discs are built mainly by relatively smooth and gradual inflow, regulated by feedback from young stars, while spheroids are built by a combination of merging, black-hole fuelling, and feedback from AGNs.