tokens: subtraction, flat-fielding, cross-talk correction, fringing, etc.). From the CP calibrated frames, we use the Astromatic 5 5 http://www.astromatic.net/ software suite (Source Extractor (SE); SCAMP; SWARP; PSFEx; Bertin Arnouts 1996 ; Bertin et al. 2002 ; Bertin 2006 ) to register frames to a common coordinate system and account for pixel scale distortions across the DECam field of view using the 2MASS astrometric reference star catalog and calibrate our photometry to the Sloan Digital Sky Survey (SDSS) system using frames of the LSE_44 SDSS southern standard star field taken at varying airmass during the observing nights. 3. Analysis 3.1. Dwarf Detection and Photometric Analysis We detect dwarf candidates using a full-color RGB image constructed from our u ′ g ′ z ′ imaging with custom Python image processing scripts. This filter combination samples the full optical spectral energy distribution (SED) and is sensitive to old, metal-poor stellar populations expected of primordial dwarf galaxies, while the inclusion of the u ′-band also serves to sample flux from younger stellar components arising from more recent star formation. Figure 1 shows the RGB image with orange dashed curves indicating NGC 5128-centric iso-radial contours. We visually searched this image for faint, extended sources displaying smooth morphologies with shallow surface-brightness ( μ ) profiles typical of low-luminosity dwarfs. Using this method, we unambiguously find 16 dwarf galaxy candidates, of which a single previously known dwarf is recovered (KK98a 189; Karachentseva Karachentsev 1998 ) and the remaining 15 are reported here for the first time, noting that one dwarf (dw1317-4255) has recently been confirmed to be a true member of the Centaurus A group Crnojević et al. 2018 ). The set of zoom-in images in Figure 1 show the dwarf candidates and measure 2′ on a side, corresponding to physical ∼2.2 × 2.2 kpc 2 regions at the distance of NGC 5128. We point out that by employing a “by eye” detection technique, we are unable to make a robust estimate of the completeness limit to our imaging in a straightforward manner and thus cannot make broad statements on the true total population of dwarfs in this region. We instead defer such an analysis to a future work detailing the overall properties of dwarfs detected throughout our survey region, noting that a lack of completeness estimate does not affect our conclusions. Figure 1. Locations of the new dwarf galaxy candidates on a u ′ g ′ z ′-based RGB color image. White-bordered images show 15 × 15 cutouts centered on the dwarfs, corresponding to ∼1.7 × 1.7 kpc 2 at the distance of NGC 5128. The scale of the background frame is indicated in the lower-left corner. Dashed orange curves show distances corresponding to 100, 150, and 200 kpc from NGC 5128. North is up, east is to the left. We use galfit (v3.0.5; Peng et al. 2010 ) to measure the structural and photometric properties of the dwarfs. We first create 365 × 365 (4 × 4 kpc
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