Recent observations of r-process-enriched metal-poor star abundances reveal a non-uniform abundance pattern for elements Z \leq 47 .
Based on non-correlation trends between elemental abundances as a function of Eu-richness in a large sample of metal-poor stars , it is shown that the mixing of a consistent and robust light element primary process ( LEPP ) and the r-process pattern found in r-II metal-poor stars explains such apparent non-uniformity .
Furthermore , we derive the abundance pattern of the LEPP from observation and show that it is consistent with a missing component in the solar abundances when using a recent s-process model .
As the astrophysical site of the LEPP is not known , we explore the possibility of a neutron capture process within a site-independent approach .
It is suggested that scenarios with neutron densities n _ { n } \leq 10 ^ { 13 } cm ^ { -3 } or in the range n _ { n } \geq 10 ^ { 24 } cm ^ { -3 } best explain the observations .