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In this paper we identify and study the properties of low mass dwarf satellites of a nearby Local Group analogue - the NGC-3175 galaxy group with the goal of investigating the nature of the lowest mass galaxies and the `Missing Satellites problem. Deep imaging of nearby groups such as NGC-3175 are one of the only ways to probe these low mass galaxies which are important for problems in cosmology, dark matter and galaxy formation. We discover 553 candidate dwarf galaxies in the group, the vast majority of which have never been studied before. We obtained R and B band imaging, with the ESO 2.2m, around the central $sim$500kpc region of NGC-3175, allowing us to detect galaxies down to $sim$23 mag (M$_{B} sim$-7.7 mag) in the B band. In the absence of spectroscopic information, dwarf members and likely background galaxies are separated using colour, morphology and surface brightness criteria. We compare the observed size, surface brightness and mass scaling relations to literature data. The luminosity function with a faint end slope of $alpha$ = -1.31, is steeper than that observed in the Local Group. In comparison with simulations, we find that our observations are between a pure $Lambda$CDM model and one involving baryonic effects, removing the apparent problem of finding too few satellites as seen around the Milky Way.
Motivated by the stellar fossil record of Local Group (LG) dwarf galaxies, we show that the star-forming ancestors of the faintest ultra-faint dwarf galaxies (UFDs; ${rm M}_{rm V}$ $sim -2$ or ${rm M}_{star}$ $sim 10^{2}$ at $z=0$) had ultra-violet (
We present a semi-analytic model of satellite galaxies, SatGen, which can generate large samples of satellite populations for a host halo of desired mass, redshift, and assembly history. The model combines dark-matter halo merger trees, empirical rel
While many tensions between Local Group (LG) satellite galaxies and LCDM cosmology have been alleviated through recent cosmological simulations, the spatial distribution of satellites remains an important test of physical models and physical versus n
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 very faint dw
Recent estimates of the Cepheid distance modulus of NGC 6822 differ by 0.18 mag. To investigate this we present new multi-epoch JHKs photometry of classical Cepheids in the central region of NGC 6822 and show that there is a zero-point difference fro