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We present deep, wide-field imaging of the M96 galaxy group (also known as the Leo I Group). Down to surface brightness limits of $mu_{B}=30.1$ and $mu_{V}=29.5$, we find no diffuse, large-scale optical counterpart to the Leo Ring, an extended HI ring surrounding the central elliptical M105 (NGC 3379). However, we do find a number of extremely low surface-brightness ($mu_{B} gtrsim 29$) small-scale streamlike features, possibly tidal in origin, two of which may be associated with the Ring. In addition we present detailed surface photometry of each of the groups most massive members -- M105, NGC 3384, M96 (NGC 3368), and M95 (NGC 3351) -- out to large radius and low surface brightness, where we search for signatures of interaction and accretion events. We find that the outer isophotes of both M105 and M95 appear almost completely undisturbed, in contrast to NGC 3384 which shows a system of diffuse shells indicative of a recent minor merger. We also find photometric evidence that M96 is accreting gas from the HI ring, in agreement with HI data. In general, however, interaction signatures in the M96 Group are extremely subtle for a group environment, and provide some tension with interaction scenarios for the formation of the Leo HI Ring. The lack of a significant component of diffuse intragroup starlight in the M96 Group is consistent with its status as a loose galaxy group in which encounters are relatively mild and infrequent.
Using deep g,r,i imaging from the VEGAS survey, we have searched for ultra diffuse galaxies (UDGs) in the IC 1459 group. Assuming they are group members, we identify 9 galaxies with physical sizes and surface brightnesses that match the UDG criteria
We use a stacking method to study the radial light profiles of luminous red galaxies (LRGs) at redshift $sim 0.62$ and $sim 0.25$, out to a radial range of 200 kpc. We do not find noticeable evolution of the profiles at the two redshifts. The LRG pro
Many ultra diffuse galaxies (UDGs) have now been identified in clusters of galaxies. However, the number of nearby UDGs suitable for detailed follow-up remain rare. Our aim is to begin to identify UDGs in the environments of nearby bright early-type
We determine the distances to the Type Ia Supernova host galaxies M66 (NGC 3627) and M96 (NGC 3368) of the Leo I Group using the Tip of the Red Giant Branch (TRGB) method. We target the stellar halos of these galaxies using the Hubble Space Telescope
The possibility that ultra-diffuse galaxies lacking dark matter has recently stimulated interest to check the validity of Modified Newton Dynamics (MOND) predictions on the scale of such galaxies. It has been shown that the External Field Effect (EFE