The genesis and chemical patterns of the metal poor stars in the galactic halo remains an open question .
Current models do not seem to give a satisfactory explanation for the observed abundances of Lithium in the galactic metal-poor stars and the existence of carbon-enhanced metal-poor ( CEMP ) and Nitrogen-enhanced metal-poor ( NEMP ) stars .
In order to deal with some of these theoretical issues , we suggest an alternative explanation , where some of the Pop .
III SNe are followed by the detonation of their neutron stars ( Quark-Novae ; QNe ) .
In QNe occurring a few days to a few weeks following the preceding SN explosion , the neutron-rich relativistic QN ejecta leads to spallation of ^ { 56 } Ni processed in the ejecta of the preceding SN explosion and thus to “ iron/metal impoverishment ” of the primordial gas swept by the combined SN + QN ejecta .
We show that the generation of stars formed from fragmentation of pristine clouds swept-up by the combined SN + QN ejecta acquire a metallicity with -7.5 < { [ Fe / H ] } < -1.5 for dual explosions with 2 < t _ { delay } ( { days } ) < 30 .
Spallation leads to the depletion of ^ { 56 } Ni and formation of sub-Ni elements such as Ti , V , Cr , and Mn providing a reasonable account of the trends observed in galactic halo metal-poor stars .
CEMP stars form in dual explosions with short delays ( t _ { delay } < 5 days ) .
These lead to important destruction of ^ { 56 } Ni ( and thus to a drastic reduction of the amount of Fe in the swept up cloud ) while preserving the carbon processed in the outer layers of the SN ejecta .
Lithium is produced from the interaction of the neutron-rich QN ejecta with the outer ( oxygen-rich ) layers of the SN ejecta .
A Lithium plateau with 2 < { A ( Li ) } < 2.4 can be produced in our model as well as a corresponding ^ { 6 } Li plateau with ^ { 6 } Li/ ^ { 7 } Li < 0.3 .