We investigate the relationship between explosion energy and nucleosynthesis in Population III supernovae and provide nucleosynthetic results for the explosions of stars with progenitor masses of 15 M , 20 M , 30 M , 40 M , 60 M , and 80 M , and explosion energies between approximately 10 50 erg and 10 53 erg. We find that the typical abundance pattern observed in metal-poor stars are best matched by supernovae with progenitor mass in the range 15 M -30 M , and explosion energy of ∼ (5 − 10) × 10 51 erg. In these models, a reverse shock caused by jumps in density between shells of different composition serves to decrease synthesis of chromium and manganese, which is favourable to matching the observed abundances in metal-poor stars. Spherically symmetric explosions of our models with progenitor mass ≥ 40 M do not provide yields that are compatible with the iron-peak abundances that are typically observed in metal-poor stars, however, by approximating the yields that we might expect from these models in highly aspherical explosions, we find indications that explosions of stars 40 M -80 M with bipolar jets may be good candidates for the enrichment sources of metal-poor stars with enhanced carbon abundances.

Hypernovae powered by magnetic jets launched from the surface of rapidly rotating millisecond magnetars are one of the leading models to explain broad-lined Type Ic supernovae (SNe Ic-BL), and have been implicated as an important source of metal enrichment in the early Universe. We investigate the nucleosynthesis in such jet-driven hypernovae using a parametrized, but physically motivated, approach that analytically relates an artificially injected jet energy flux to the power available from the energy in differential rotation in the protoneutron star. We find ejected 56Ni masses of $0.05\, \!-\!0.45\, \mathrm{M}_\odot$ in our most energetic models with explosion energy $\gt 10^{52}\, \mathrm{erg}$. This is in good agreement with the range of observationally inferred values for SNe Ic-BL. The 56Ni is mostly synthesized in the shocked stellar envelope, and is therefore only moderately sensitive to the jet composition. Jets with a high electron fraction Ye = 0.5 eject more 56Ni by a factor of 2 than neutron-rich jets. We can obtain chemical abundance profiles in good agreement with the average chemical signature observed in extremely metal-poor (EMP) stars presumably polluted by hypernova ejecta. Notably, [Zn/Fe] ≳ 0.5 is consistently produced in our models. For neutron-rich jets, there is a significant r-process component, and agreement with EMP star abundances in fact requires either a limited contribution from neutron-rich jets or a stronger dilution of r-process material in the interstellar medium than for the slow SN ejecta outside the jet. The high [C/Fe] ≳ 0.7 observed in many EMP stars cannot be consistently achieved due to the large mass of iron in the ejecta, however, and remains a challenge for jet-driven hypernovae based on the magnetorotational mechanism.