Milena Valentini

Ludwig-Maximilians-University of Munich | LMU · Computational Astrophysics Group at the University Observatory

We study the impact of relatively weak active galactic nucleus (AGN) feedback on the interstellar medium (ISM) of intermediate and massive elliptical galaxies. We find that the AGN activity, while globally heating the ISM, naturally stimulates some degree of hot gas cooling on scales of several kpc. This process generates the persistent presence of...

We investigate the impact of galactic outflow modelling on the formation and evolution of a disc galaxy, by performing a suite of cosmological simulations with zoomed-in initial conditions of a Milky Way-sized halo. We verify how sensitive the general properties of the simulated galaxy are to the way in which stellar feedback triggered outflows are...

State-of-the-art cosmological hydrodynamical simulations have star particles with a typical mass between ~10⁸ and ~10³ M⊙ according to resolution, and treat them as simple stellar populations. On the other hand, observations in nearby galaxies resolve individual stars and provide us with single star properties. An accurate and fair comparison betwe...

We perform a suite of cosmological hydrodynamical simulations of disc galaxies, with zoomed-in initial conditions leading to the formation of a halo of mass Mhalo, DM ≃ 2 · 10¹² M⊙ at redshift z = 0. These simulations aim at investigating the chemical evolution and the distribution of metals in a disc galaxy, and at quantifying the effect of (i) th...

We present simulations of galaxy formation, based on the GADGET-3 code, in which a sub-resolution model for star formation and stellar feedback is interfaced with a new model for AGN feedback. Our sub-resolution model describes a multiphase ISM, accounting for hot and cold gas within the same resolution element: we exploit this feature to investiga...

The large total infrared (TIR) luminosities (LTIR ≳ 1012 L⊙) observed in z ∼ 6 quasars are generally converted into high star formation rates (SFR ≳ 102 M⊙ yr−1) of their host galaxies. However, these estimates rely on the assumption that dust heating is dominated by stellar radiation, neglecting the contribution from the central Active Galactic Nu...

The evolution of the Kelvin-Helmholtz Instability (KHI) is widely used to assess the performance of numerical methods. We employ this instability to test both the smoothed particle hydrodynamics (SPH) and the meshless finite mass (MFM) implementation in OpenGadget3. We quantify the accuracy of SPH and MFM in reproducing the linear growth of the KHI...

Context. Recent observations found that observed cluster member galaxies are more compact than their counterparts in ΛCDM hydrodynamic simulations, as indicated by the difference in their strong gravitational lensing properties, and they reported that measured and simulated galaxy–galaxy strong lensing events on small scales are discrepant by one o...

We investigate shock structures driven by merger events in high-resolution simulations that result in a galaxy with a virial mass M ~ 1e12 Msol. We find that the sizes and morphologies of the internal shocks resemble remarkably well those of the newly-detected class of odd radio circles (ORCs). This would highlight a so-far overlooked mechanism to...

The reservoir of molecular gas (H$_{\rm 2}$) represents the fuel for the star formation (SF) of a galaxy. Connecting the star formation rate (SFR) to the available H$_{\rm 2}$ is key to accurately model SF in cosmological simulations of galaxy formation. We investigate how modifying the underlying modelling of H$_{\rm 2}$ and the description of ste...

We study the evolution of dust in a cosmological volume using a hydrodynamical simulation in which the dust production is coupled with the MUPPI (MUlti Phase Particle Integrator) sub-resolution model of star formation and feedback. As for the latter, we keep as reference the model setup calibrated previously to match the general properties of Milky...

Meneghetti et al. (2020) recently reported an excess of galaxy-galaxy strong lensing (GGSL) in galaxy clusters compared to expectations from the LCDM cosmological model. Theoretical estimates of the GGSL probability are based on the analysis of numerical hydrodynamical simulations in the LCDM cosmology. We quantify the impact of the numerical resol...

The properties of quasar-host galaxies might be determined by the growth and feedback of their supermassive (SMBH, $10^{8-10}$ M$_{\odot}$) black holes. We investigate such connection with a suite of cosmological simulations of massive (halo mass $\approx 10^{12}$ M$_{\odot}$) galaxies at $z\simeq 6$ which include a detailed sub-grid multiphase gas...

We present cosmological zoom-in hydro-dynamical simulations for the formation of disc galaxies, implementing dust evolution and dust promoted cooling of hot gas. We couple an improved version of our previous treatment of dust evolution, which adopts the two-size approximation to estimate the grain size distribution, with the MUPPI star formation an...

We analyse from an observational perspective the formation history and kinematics of a Milky Way-like galaxy from a high-resolution zoom-in cosmological simulation that we compare to those of our Galaxy as seen by Gaia DR2 to better understand the origin and evolution of the Galactic thin and thick discs. The cosmological simulation was carried out...

We present cosmological zoom-in hydro-dynamical simulations for the formation of disc galaxies, implementing dust evolution and dust promoted cooling of hot gas. We couple an improved version of our previous treatment of dust evolution, which adopts the two-size approximation to estimate the grain size distribution, with the MUPPI star formation an...

State-of-the-art cosmological hydrodynamical simulations have star particles with typical mass between $\sim$$10^8$ and $\sim$$10^3$ M$_{\odot}$ according to resolution, and treat them as simple stellar populations. On the other hand, observations in nearby galaxies resolve individual stars and provide us with single star properties. An accurate an...