Constraining the origin and models of chemical enrichment in galaxy clusters using the Athena X-IFU

The chemical enrichment of the Universe at all scales is related to stellarwinds and explosive supernovae phenomena. Metals produced by stars and laterspread at the mega-parsec scale through the intra-cluster medium (ICM) become afossil record of the chemical enrichment of the Universe and of the dynamicaland feedback mechanisms determining their circulation. As demonstrated by theresults of the soft X-ray spectrometer onboard Hitomi, high resolution X-rayspectroscopy is the path to to differentiate among the models that considerdifferent metal production mechanisms, predict the outcoming yields, and arefunction of the nature, mass, and/or initial metallicity of their stellarprogenitor. Transformational results shall be achieved through improvements inthe energy resolution and effective area of X-ray observatories to detect raremetals (e.g. Na, Al) and constrain yet uncertain abundances (e.g. C, Ne, Ca,Ni). The X-ray Integral Field Unit (X-IFU) instrument onboard thenext-generation European X-ray observatory Athena is expected to deliver suchbreakthroughs. Starting from 100 ks of synthetic observations of 12 abundanceratios in the ICM of four simulated clusters, we demonstrate that the X-IFUwill be capable of recovering the input chemical enrichment models at both low($z = 0.1$) and high ($z = 1$) redshifts, while statistically excluding morethan 99.5% of all the other tested combinations of models. By fixing theenrichment models which provide the best fit to the simulated data, we alsoshow that the X-IFU will constrain the slope of the stellar initial massfunction within $\sim$12%. These constraints will be key ingredients in ourunderstanding of the chemical enrichment of the Universe and its evolution.