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Inhomogeneous chemical evolution models of galaxies which try to reproducethe scatter seen in element-to-iron ratios of metal-poor halo stars are heavilydependent on theoretical nucleosynthesis yields of core-collapse supernovae.Hence inhomogeneous models present themselves as a test for stellar nucleosyn-thesis calculations. Applying an inhomogeneous chemical evolution model to ourGalaxy reveals a number of shortcomings of existing theoretical nucleosynthesisyields. One problem is the predicted scatter in [O/Fe] and [Mg/Fe] which is toolarge compared to the one observed in metal-poor halo stars. This can be eitherdue to the O or Mg yields or due to the Fe yields (or both). However, O and Mgare alpha-elements that are produced mainly during hydrostatic burning and thusare not affected by the theoretical uncertainties afflicting the collapse andexplosion of a massive star. Stellar iron yields, on the other hand, dependheavily on the choice of the mass-cut between ejecta and proto neutron star andare therefore very uncertain. We present Fe yield distributions as function ofprogenitor mass that are consistent with the abundance distribution of metal-poor halo stars and are in agreement with observed Ni yields of SNe II withknown progenitor masses. The iron yields of lower-mass SNe II (in the range10-20 Msol) are well constrained by those observations. Present observations,however, do not allow to determine a unique solution for higher-mass SNe.Nevertheless, the main dependence of the stellar iron yield as function ofprogenitor mass may be derived and can be used as constraint for futuresupernova/hypernova models. The results are of importance for the earlieststages of galaxy formation when the ISM is dominated by chemicalinhomogeneities and the instantaneous mixing approximation is not valid.Comment: 16 pages, 15 figures, submitted to A&A, for higher quality figures  contact the author (argast@astro.unibas.ch

Implications of O and Mg abundances in metal-poor halo stars for stellar iron yields