Cococubed.com Pressure from the LS and an NSE EOS

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Contact: F.X.Timmes
my one page vitae,
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teaching statement.

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 Pressure:
 Pressure from baryons Ye=0.5 Pressure from baryons Ye=0.4 Pressure from baryons Ye=0.3 Pressure from baryons Ye=0.2

In certain regions of the rho-T plane, contributions from the coulomb lattice terms cause the baryon pressure to become negative.

LS Total Pressure:
 Total pressure Ye=0.5 Total pressure Ye=0.4 Total pressure Ye=0.3 Total pressure Ye=0.2

NSE Baryon Pressure:
 Pressure from baryons Ye=0.5 Pressure from baryons Ye=0.4 Pressure from baryons Ye=0.3 Pressure from baryons Ye=0.2

Even though the nuclei in the NSE-based model are a perfect gas, the surface isn't planar because of the changing composition. This causes the ripples in the surface.

NSE Total Pressure:
 Total pressure Ye=0.5 Total pressure Ye=0.4 Total pressure Ye=0.3 Total pressure Ye=0.2

LS and NSE Pressures Compared:
 Pressure Ye=0.5 Pressure Ye=0.4 Pressure Ye=0.3 Pressure Ye=0.2

 Pressure differences Ye=0.5 Pressure differences Ye=0.4 Pressure differences Ye=0.3 Pressure differences Ye=0.2