Related papers: The faint end of the Centaurus A satellite luminos…
We present the widest-field resolved stellar map to date of the closest ($D\sim3.8$ Mpc) massive elliptical galaxy NGC 5128 (Centaurus A; Cen A), extending out to a projected galactocentric radius of $\sim150$ kpc. The dataset is part of…
In the wide-field Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS), we investigate the resolved stellar halos of two nearby galaxies (the elliptical Centaurus A and the spiral Sculptor, D $\sim3.7$ Mpc) out to a projected…
Dwarf galaxy satellite systems are essential probes to test models of structure formation, making it necessary to establish a census of dwarf galaxies outside of our own Local Group. We present deep FORS2 VI band images from the ESO Very…
As part of the Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) we report the discovery of a pair of faint dwarf galaxies (CenA-MM-Dw1 and CenA-MM-Dw2) at a projected distance of $\sim$90 kpc from the nearby elliptical galaxy…
We have completed a 21-cm survey of a 600 square degree region of the Centaurus A group of galaxies at a redshift of ~500 km/s as part of a larger survey of the entire southern sky. This group of galaxies was recently the subject of a…
We conducted an extensive CCD search for faint, unresolved dwarf galaxies of very low surface brightness in the whole Centaurus group region encompassing the Cen A and M 83 subgroups lying at a distance of roughly 4 and 5 Mpc, respectively.…
We have commenced a 21-cm survey of the entire southern sky (\delta < 0 degrees, -1200 km/s < v < 12700 km/s) which is ''blind'', i.e. unbiased by previous optical information. In the present paper we report on the results of a pilot…
For the first time, systematic studies of dwarf galaxies are being conducted throughout the Local Volume, including the dwarf satellites of the nearby giant elliptical galaxy Centaurus A (NGC 5128). Given Centaurus As mass (roughly ten…
The existence of satellite galaxy planes poses a major challenge for the standard picture of structure formation with non-baryonic dark matter. Recently Tully et al. (2015) reported the discovery of two almost parallel planes in the nearby…
We study dwarf galaxies in the Centaurus A group to investigate their metallicity and possible environmental effects. The Centaurus A group (at ~4 Mpc from the Milky Way) contains about 50 known dwarf companions of different morphologies…
Dwarf spheroidal galaxies (dSphs) have been extensively investigated in the Local Group, but their low luminosity and surface brightness make similar work in more distant galaxy groups challenging. Modern instrumentation unlocks the…
We present the first deep survey of resolved stellar populations in the remote outer halo of our nearest giant elliptical (gE), Centaurus A (D=3.8 Mpc). Using the VIMOS/VLT optical camera, we obtained deep photometry for four fields along…
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 (KK208) surrounding the nearby grand…
We present results of two 21-cm HI surveys performed with the Australia Telescope Compact Array in the nearby Centaurus A and Sculptor galaxy groups. These surveys are sensitive to compact HI clouds and galaxies with HI masses as low as…
We have conducted a systematic search around the Milky Way (MW) analog NGC 253 (D=3.5 Mpc), as a part of the Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) - a Magellan+Megacam survey to identify dwarfs and other substructures…
The flattened, possibly co-rotating plane of satellite galaxies around Centaurus A, if more than a fortuitous alignment, adds to the pre-existing tension between the well-studied Milky Way and M31 planes and the $\Lambda$CDM model of…
In the last years, a new generation of large-scale imaging surveys have probed wide field regions around some nearby galaxies at unprecedented low surface brightness regime (~28.0-29.0 mag arcsec^-2). This offers a chance of discovering…
We present deep Hubble Space Telescope imaging of five faint dwarf galaxies associated with the nearby spiral NGC 253 (D$\approx$3.5 Mpc). Three of these are newly discovered ultra-faint dwarf galaxies, while all five were found in the…
In the coming decade, thousands of stellar streams will be observed in the halos of external galaxies. What fundamental discoveries will we make about dark matter from these streams? As a first attempt to look at these questions, we model…
The plane-of-satellites problem is one of the most severe small-scale challenges for the standard $\Lambda$CDM cosmological model: several dwarf galaxies around the Milky Way and Andromeda co-orbit in thin, planar structures. A similar case…