VST-SMASH: VST Survey of Mass Assembly and Structural Hierarchy. II. Exploring dwarf galaxies in the vicinity of NGC 5068 and of the two galaxies NGC 5084 and NGC 5087 at the edges of the Virgo Supercluster

We present a study of dwarf galaxy candidates in the deepest optical imaging obtained to date of the field surrounding the nearby galaxies NGC 5068 (5.2 Mpc) and NGC 5084/NGC 5087 (25-30 Mpc). The latter two are located in the peripheries of the Virgo Supercluster. This field, covering ∼ 2.6 deg2$, was observed as part of the multi-band, wide-field, and very deep data from VST Survey of Mass Assembly and Structural Hierarchy (VST-SMASH), a distance-limited programme (D < 11 Mpc) that reaches g- and r-band surface brightness depths of μ ∼ 30 mag arcsec^-2 within a box of 10 at 1σ. Using a two-step visual inspection procedure, we identified 47 dwarf galaxy candidates and performed a surface photometry study of the sample, along with a fitting procedure with 1D Sérsic model on their profiles. Only four galaxies had previously been reported in the literature, augmenting the number of dwarfs discovered in these regions by one order of magnitude. The colours (median g-r = 0.57 mag and r-i = 0.24 mag) and structural properties of the dwarf candidates are consistent with the literature, as are their scaling relations with effective radius, Sersic index (n$< 2), and absolute magnitude. We also investigated their central colour gradients, which exhibit significant scatter. We discuss them within the broader context of galaxy formation and also analyse the spatial distribution of these dwarf candidates relative to potential host galaxies. Considering the projected separation, we identified reasonable associations with NGC 5084, NGC 5087, and NGC 5068 as likely hosts for a significant fraction of the sample. Several candidates are at physically credible distances from NGC 5068, despite what their offset size-luminosity relation alone might suggest. Future spectroscopic and deeper imaging follow-ups are required to determine distances and velocities, enabling a robust association with hosts, studies of satellite distributions and counts, and comparisons with cosmological expectations for planes in the context of satellites and dark matter models. 10, ̊m arcsec^ 2