Probing gas properties out to the virial radius of the MKW4 galaxy group using joint Suzaku and Chandra observations

With a global temperature of 1.6 keV, MKW4 is one of the smallest galaxy groups that have been mapped in X-rays out to the virial radius. Unlike massive clusters, the outskirts of galaxy groups are relatively unexplored due to their low surface brightness. The typical ICM surface brightness in group outskirts falls below 20% of the total emission. The measurement of their gas properties is therefore extremely challenging. We utilize deep Suzaku and snapshot Chandra observations to probe the gas properties and metallicity distribution of MKW4 out to its virial radius in multiple directions. We compare its entropy profile to the self-similar entropy profile obtained from the gravitational collapse model and constrain the ICM properties at the outskirts as well as in the group center. We measure the baryon fraction of MKW4 and show the impacts of AGN feedback and galactic winds. We are able to obtain the metallicity profiles of several elements and estimate the metal mass-to-light ratio from the group center out to 0.65R_vir.