Publications de Nick Heesters | EPFL Graph Search

MUSE observations of dwarf galaxies and a stellar stream in the M 83 group

Spectroscopy for faint dwarf galaxies outside of our own Local Group is challenging. Here, we present MUSE spectroscopy to study the properties of four known dwarf satellites and one stellar stream (KK 208) surrounding the nearby grand spiral M 83, which r ...

2025

Dwarf galaxies in the MATLAS survey: The satellite system of NGC 474 under scrutiny with MUSE

Oliver Müller, Nick Heesters

A recent study of the distribution of dwarf galaxies in the MATLAS sample in galaxy groups revealed an excess of flattened satellite structures, reminiscent of the co-rotating planes of dwarf galaxies discovered in the local Universe. If confirmed, this le ...

2025

Galaxies OBserved as Low-luminosity Identified Nebulae (GOBLIN): Catalog of 43 000 high-probability dwarf galaxy candidates in the UNIONS survey

Nick Heesters

The detection of low-surface-brightness galaxies beyond the Local Group poses significant observational challenges, yet these faint systems are fundamental to our understanding of dark matter, hierarchical galaxy formation, and cosmic structure. Their abun ...

2025

The satellite galaxy plane of NGC 4490 in light of ΛCDM: Sparsity of similarly extreme analogs and a possible role of satellite pairs

Oliver Müller, Nick Heesters

Context. The system of galaxies around NGC 4490 was recently highlighted to display a flattened, kinematically correlated structure reminiscent of planes of satellite galaxies around other hosts. Aims. Since known satellite planes are in tension with expec ...

2024

The phase-space distribution of the M 81 satellite system

Oliver Müller, Nick Heesters

The spatial distribution of dwarf galaxies around their host galaxies is a critical test for the standard model of cosmology because it probes the dynamics of dark matter halos and is independent of the internal baryonic processes of galaxies. Comoving pla ...

Edp Sciences S A2024

Lopsided distribution of MATLAS and ELVES dwarf satellite systems around isolated host galaxies

Oliver Müller, Nick Heesters

The properties of satellite dwarf galaxies provide important empirical insights for verifying cosmological models on galaxy scales. Their phase-space correlations, in particular, offer interesting insights into a broad range of models, since they are domin ...

2024

A too-many dwarf satellite galaxies problem in the MATLAS low-to-moderate density fields

Oliver Müller, Nick Heesters

Context. Dwarf galaxy abundances can serve as discernment tests for models of structure formation. Previous small-scale tensions between observations and dark matter-only cosmological simulations may have been resolved with the inclusion of baryonic proces ...

2024

The creation of a massive UCD by tidal threshing from NGC936

Oliver Müller, Nick Heesters

We study a compact nucleus embedded in an early-type dwarf galaxy, MATLAS-167, which is in the process of disruption by the tidal force of the neighbouring giant S0 galaxy, NGC936, in a group environment. Using the imaging data of the MATLAS survey, we ana ...

Oxford Univ Press2023

Radial velocities and stellar population properties of 56 MATLAS dwarf galaxies observed with MUSE

Nick Heesters

Dwarf galaxies have been extensively studied in the Local Group, in nearby groups, and selected clusters, giving us a robust picture of their global stellar and dynamical properties, such as their circular velocity, stellar mass, surface brightness, age, a ...

EDP SCIENCES S A2023

A possible dwarf galaxy satellite-of-satellite problem in ?CDM

Yves Revaz, Nick Heesters

Dark matter clusters on all scales, and it is therefore expected that even substructure should host its own substructure. Using the Extragalactic Distance Database, we searched for dwarf-galaxy satellites of dwarf galaxies, that is, satellite-of-satellite ...

EDP SCIENCES S A2023