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Dwarf spheroidal galaxies (dSphs) have been extensively investigated in theLocal Group, but their low luminosity and surface brightness make similar workin more distant galaxy groups challenging. Modern instrumentation unlocks thepossibility of scrutinizing these faint systems in other environments,expanding the parameter space of group properties. We use MUSE spectroscopy tostudy the properties of 14 known or suspected dSph satellites of Cen A. Twelvetargets are confirmed to be group members based on their radial velocities. Twotargets are background galaxies at 50 Mpc: KK 198 is a face-on spiral galaxy,and dw1315-45 is an ultra-diffuse galaxy with an effective radius of 2300 pc.The 12 confirmed dSph members of the Cen A group have old and metal-poorstellar populations and follow the stellar metallicity-luminosity relationdefined by the dwarf galaxies in the Local Group. In the three brightest dwarfgalaxies (KK 197, KKs 55, and KKs 58), we identify globular clusters, as wellas a planetary nebula in KK 197, although its association with this galaxyand/or the extended halo of Cen A is uncertain. Using four discrete tracers, wemeasure the velocity dispersion and dynamical mass of KK 197. This dSph appearsdark matter dominated and lies on the radial acceleration relation ofstar-forming galaxies within the uncertainties. It also is consistent withpredictions stemming from modified Newtonian dynamics (MOND). Surprisingly, inthe dwarf KK 203 we find an extended Halpha ring. Careful examination of HubbleSpace Telescope photometry reveals a very low level of star formation at agesbetween 30-300 Myr. The Halpha emission is most likely linked to a 40 Myr oldsupernova remnant, although other possibilities for its origin cannot beentirely ruled out.

The properties of dwarf spheroidal galaxies in the Cen A group: Stellar populations, internal dynamics, and a heart-shaped Halpha ring