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Pressure from the LS and an NSE EOS




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Contact: F.X.Timmes
my one page vitae,
full vitae,
research statement, and
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:
image
Pressure from baryons Ye=0.5
image
Pressure from baryons Ye=0.4
image
Pressure from baryons Ye=0.3
image
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:
image
Total pressure Ye=0.5
image
Total pressure Ye=0.4
image
Total pressure Ye=0.3
image
Total pressure Ye=0.2


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


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


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