We present new observations of copper and zinc abundances in 90 metal-poor stars , belonging to the metallicity range –3 < [ Fe/H ] < –0.5 .
The present study is based on high resolution spectroscopic measurements collected at the Haute Provence Observatoire ( R= 42000 , S/N > 100 ) .
The trend of Cu and Zn abundances as a function of the metallicity [ Fe/H ] is discussed and compared to that of other heavy elements beyond iron .
We also estimate spatial velocities and galactic orbital parameters for our target stars in order to disentangle the population of disk stars from that of halo stars using kinematic criteria .
In the absence of a firm a priori knowledge of the nucleosynthesis mechanisms controlling Cu and Zn production , and of the relative stellar sites , we derive constraints on these last from the trend of the observed ratios [ Cu/Fe ] and [ Zn/Fe ] throughout the history of the Galaxy , as well as from a few well established properties of basic nucleosynthesis processes in stars .
We thus confirm that the production of Cu and Zn requires a number of different sources ( neutron captures in massive stars , s - processing in low and intermediate mass stars , explosive nucleosynthesis in various supernova types ) .
We also attempt a ranking of the relative roles played by different production mechanisms , and verify these hints through a simple estimate of the galactic enrichment in Cu and Zn .
In agreement with suggestions presented earlier , we find evidence that Type Ia Supernovae must play a relevant role , especially for the production of Cu .