T_{\rm peak}^4 = P_{\rm shock} = 7/6 \rho_{\rm star} v_{\rm SN}^2,$$ $$\rho_{\rm peak} = 7 \rho_{\rm star}$$ where the density at the shock depends only on the stellar density ($\rho_{\rm star}$) and pressure at the supernova shock ($P_{\rm shock}$) depends on both the stellar density and the supernova shock velocity ($v_{\rm SN}$). The sensitivity of the yields to these quantities in principle allow nuclear astrophysicists to probe stellar structure and supernova properties, but to do so requires disentangling a number of complex features in these yields.

One of the issues in studying these yields is that the explosion can both create and destroy radioactive isotopes. This is particularly important for long-lived isotopes such as  [@jones2019a]. In addition, the yields are sensitive to the temperature and density evolution. A weak explosion may produce a particular isotope deep in the core whereas a stronger explosion produces this isotope further out, producing a different isotope in the core (see Figure \[fig:exampleenergy1\]). These two explosions may produce similar total masses, just in different regions of the star.

![Mass fraction of as a function of mass coordinate for each explosion scenario (color indicated by explosion energy color bar), the average of the explosions (black dashed), 