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Entropy from the LS and an NSE EOS




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J.D. Maldonado
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The electron-positron portion of the two equations of state are identical. Differences between the two EOS routines originate from the model used for nucleons (interacting nucleons in a liquid dropish model versus non-interacting Boltzmann nucleons), and the model used for the composition.

LS Baryon Entropy:
image
Entropy from baryons Ye=0.5
image
Entropy from baryons Ye=0.4
image
Entropy from baryons Ye=0.3
image
Entropy from baryons Ye=0.2


The entropy from baryons, on the other hand, appears to be well behaved everwhere is this section of the rho-T plane. In fact, baryons dominate the magnitude of the total entropy. The black ledge in the total entropy isn't real. I simply capped the largest value plotted, since the entropy skyrockets in regions where radiation and e+e- dominate.

LS Total Entropy:
image
Total entropy Ye=0.5
image
Total entropy Ye=0.4
image
Total entropy Ye=0.3
image
Total entropy Ye=0.2


NSE Baryon Entropy:
image
Entropy from baryons Ye=0.5
image
Entropy from baryons Ye=0.4
image
Entropy from baryons Ye=0.3
image
Entropy from baryons Ye=0.2


Looks a bit different than an LS based EOS. Again, the black ledge in the total entropy isn't real. I simply capped the largest value plotted.

NSE Total Entropy:
image
Total entropy Ye=0.5
image
Total entropy Ye=0.4
image
Total entropy Ye=0.3
image
Total entropy Ye=0.2


LS and NSE Entropies Compared:
image
Entropy Ye=0.5
image
Entropy Ye=0.4
image
Entropy Ye=0.3
image
Entropy Ye=0.2




image
Entropy differences Ye=0.5
image
Entropy differences Ye=0.4
image
Entropy differences Ye=0.3
image
Entropy differences Ye=0.2


The disagreements here are larger than the pressure and energy cases.