星系天体物理

Extended Ly$\alpha$ emission is ubiquitous around quasars and traces cool circumgalactic gas, providing insight into halo gas dynamics and active galactic nuclei (AGN) feedback. However, its connection to the cold molecular gas of the host…

Self-gravitating astrophysical plasmas naturally achieve a state of global electrical polarization, known as the Bally-Harrison effect, where an induced electric field counteracts the preferential thermal escape of electrons. In this work,…

It has recently been suggested that a variety of data on active galactic nuclei (AGN) can be explained if AGN disks are supported against gravitational fragmentation by magnetic fields that are advected into the disk from the surrounding…

The search for and the characterization of ultra-compact dual active galactic nuclei (AGN) are among the hottest topics of current extragalactic astrophysics. These systems involve two accreting massive black holes (MBHs) embedded within…

While AGN feedback is a key driver of massive galaxy evolution, its physical properties and observational signatures in the dwarf regime remain poorly understood. We investigate the impact of AGN-driven outflows on the ISM of dwarf galaxies…

The morphological properties of dwarf galaxies (Mstar < 10^9.5 MSun) remain largely unexplored, particularly outside the local neighbourhood. We explore how morphology changes across the massive to dwarf-galaxy regimes, using a…

Discovery of dark-matter (DM) free dwarf galaxies in the NGC 1052 neighborhood has had a considerable impact on modern cosmology. They have been explained through a dwarf--dwarf head-on collision that is a rare event. We find that they…

The early growth and assembly of supermassive black holes (SMBHs) remain key topics of interest in galaxy evolution. One of the scenarios predicted by theoretical models is that frequent minor mergers and asymmetric gas inflows may cause…

JWST's Little Red Dots (LRDs) display a unique constellation of features that do not occur simultaneously in any other class of galaxies or AGN. Here we observe that many of these features find parallels in the 19th century Great Eruption…

Recent studies of local galaxies highlight the need for high-resolution photometry and kinematics to accurately characterize galactic structures. From this, limitations emerged in the standard two-phase evolutionary scenario, where galaxies…

(abridged) The integrated X-ray luminosity (Lx) of star-forming galaxies is dominated by high-mass X-ray binary (HMXB) populations. The discrete nature of these populations introduces stochastic sampling effects that distort the X-ray…

The accretion-ejection mechanism in Active Galactic Nuclei (AGN) remains a central open problem in astrophysics, tied to the role of AGN feedback in galaxy formation and evolution. Radio-quiet AGN dominate the observed AGN population.…

We present our search for little red dots (LRDs) in the "J1030 field", a region of the sky around the $z\sim 6.3$ quasar SDSS J1030+0524, observed by the JWST EIGER program. Over 154 point-like sources selected in a JWST-based photometric…

The line spread function (LSF) of a spectrograph encodes the inherent broadening of a single spectral line. It is typically reported as a single number, the resolving power $R = \lambda/\Delta\lambda$ with $\Delta \lambda$ the FWHM of the…

Dust polarization observations are widely used to diagnose the relative importance of magnetic fields and turbulence in star forming molecular clouds, often through summary statistics such as the mean polarization direction $\mu$ and…

A primary question within galaxy evolution is how active galactic nuclei (AGN) feedback modifies the circumgalactic medium (CGM). We present a search for faint H$\alpha$ emission from the cool ionized CGM ($T\sim 10^4$ K) around radio…

Our $\psi$DM simulations predict that stars diffuse throughout dark matter halos over the Hubble time through a random walk driven by the wave perturbations intrinsic to $\psi$DM. The resulting stellar distribution locally follows a…

In order to understand the magnetization of galaxies and the role of magnetic fields in feedback processes that govern star formation and galaxy evolution, it is essential to have a comprehensive census of magnetic fields in and around…

Most XRISM galaxy cluster observations to date have focused on AGN feedback or actively merging systems. The weak cool-core cluster A3571 was observed in four XRISM Cycle 1 pointings, enabling the study of gas kinematics in a relaxed,…

Interstellar dust is a crucial asset in many astronomical observations. Characterising grains present in the dense gas and in star-forming environments is also key to constrain the pristine conditions for planetary formation. However, dust…