相关论文: The Hydra I cluster core. I. Stellar populations i…
Context. We investigate the stellar population and the origin of diffuse light around brightest cluster galaxies. Aims. We study the stellar population of the dynamically hot stellar halo of NGC 3311, the brightest galaxy in the Hydra I…
Aims. We aim to investigate the stellar population properties, ages, and metal content of the globular clusters (GCs) in NGC 3311, the central galaxy of the Hydra I cluster, to better constrain its evolution history. Methods. We used…
Several observations of the central region of the Hydra I galaxy cluster point to a multi-epoch assembly history. Using our novel FORS2/VLT spectroscopic data set, we were able to map the luminosity-weighted age, [Fe/H] and [$\alpha$/Fe]…
NGC 3311 is the central galaxy of the Hydra I galaxy cluster. It has a hot interstellar medium and hosts a central dust lane with emission lines. These dust lanes are frequent in elliptical galaxies, but the case of NGC 3311 might be…
An important open question is the relation between intracluster light and the halos of central galaxies in galaxy clusters. Here we report results from an on going project with the aim to characterize the dynamical state in the core of the…
NGC 3311, the central galaxy of the Hydra I cluster, shows signatures of recent infall of satellite galaxies from the cluster environment. Previous work has shown that the line-of-sight velocity dispersion of the stars and globular clusters…
NGC 3311 is the central cD galaxy of the Hydra I cluster. We use globular clusters around NGC 3311, combined with kinematical data of the galaxy itself, to investigate the dark matter distribution in the central region of Hydra I. Radial…
Early-type galaxies show a strong size evolution with redshift. This evolution is explained by fast "in-situ" star formation at high-$z$ followed by a late mass assembly mostly driven by minor mergers that deposit stars primarily in the…
In galaxy clusters, hierarchical assembly predicts the formation of stellar substructures and intracluster light (ICL), a diffuse stellar component tracing the global cluster potential. Because these features are extremely faint,…
The Hydra I cluster offers an excellent opportunity to study and compare the relic old stellar populations in the core of its two brightest galaxies. In addition, the differing kinematics of the two galaxies allows a test of the local…
Information on the star-formation histories of cD galaxies and their extended stellar haloes lie in their spectra. Therefore, to determine whether these structures evolved together or through a two-phase formation, we need to…
In this contribution, first results of deep VLT photometry (V,I) in the central region of the Hydra I galaxy cluster are presented. Many star clusters have been identified not only around several early-type galaxies, but also in the…
We have obtained V and I-band photometry for about 17500 stars in the field of the dwarf irregular galaxy NGC3109, located in the outskirts of the Local Group. The photometry allows us to study the stellar populations present inside and…
The formation of intracluster light and of the extended halos around brightest cluster galaxies is closely related to morphological transformation, tidal stripping, and disruption of galaxies in clusters. We analyze Ks- and V-band surface…
We present extensive new photometry in (g',i') of the large globular cluster (GC) system around NGC 3311, the central cD galaxy in the Hydra cluster. Our GMOS data cover a 5.5' field of view and reach a limiting magnitude i' = 26, about 0.5…
NGC 3311, the central cD galaxy in the Hydra cluster, was previously thought to host the most metal-rich globular cluster system known. Ground-based Washington photometry had indicated the almost complete absence of the population of…
Massive early-type galaxies are believed to be the end result of an extended mass accretion history. The stars formed in situ very early on in the initial phase of the assembly might have originated from an extremely intense star formation…
We use the ages, masses and metallicities of the rich young star cluster systems in the nearby starburst galaxies NGC 3310 and NGC 6745 to derive their cluster formation histories and subsequent evolution. We further expand our analysis of…
The properties of globular cluster systems (GCSs) in the core of the nearby galaxy clusters Fornax and Hydra I are presented. In the Fornax cluster we have gathered the largest radial velocity sample of a GCS system so far, which enables us…
We used FORS2 in MXU mode to mimic a coarse 'IFU' in order to measure the 3D large-scale kinematics around the central Hydra I cluster galaxy NGC 3311. Our data show that the velocity dispersion field varies as a function of radius and…