The cycle of metals in the infalling elliptical galaxy NGC 1404

Hot atmospheres pervading galaxy clusters, groups, and early-type galaxies are rich in metals, produced during epochs diffused via processes that still to be determined. While this enrichment has been routinely investigated metals lower mass systems more challenging probe with standard X-ray exposures spectroscopy. In paper, we focus on very deep XMM-Newton ($\sim$350 ks) observations of NGC 1404, a massive elliptical experiencing ram-pressure stripping its hot atmosphere while infalling toward the centre Fornax cluster, aim derive abundances through gas extent. Importantly, report existence new fitting bias - "double Fe bias" leading an underestimate abundance when two thermal components cannot realistically model complex temperature structure present outer galaxy. Contrasting ''metal conundrum'' seen Mg masses 1404 measured 1-2 orders magnitude below what stars supernovae could have reasonably released. addition, note remarkable Solar ratios galaxy's halo, different from stellar counterpart but similar chemical composition ICM clusters. Completing clusters regime, all these findings provide additional support scenario early enrichment, at play over mass. A few peculiar intriguing features, such as possible double metal peak well apparent ring enhanced Si near core, also discussed.