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Initial Conditions for the hydro quantities
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## Density
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The surface density distribution follows a power law:
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$`\Sigma(r) = \Sigma_0(r/R0)^{-\alpha}`$
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with $`\Sigma_0`$ the surface density at $r/R0=1$ and $\alpha$ the
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slope of the power law.
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$`\Sigma_0`$ in code unit is the parameter ```Start``` in the configuration file and
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```$`\alpha`$``` is Slope. They are provided in the ```Density``` block as follows:
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```
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Density
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{
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Slope 0.5
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Minimum 1.e-20
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Start 0.0006
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}
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```
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Notice that the user can define a density floor: ```Minimum```
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in c.g.s, i.e. $g/cm^3$ in the case of a 3D simulation and $g/cm^2$ for 2D simulations.
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The volume density is obtained by the hydrostatical equilibrium in the thin disk approximation. In cylindrical coordinates it reads:
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$`\rho(R,z) = \rho_0(R) \exp(-R^2/(2H^2)`$
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with $`\rho_0(R) = \Sigma_0 R^{-\alpha-1-\beta}/h_02\pi`$
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## Radial Velocity
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## Azimuthal Velocity
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## Polar velocity |
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\ No newline at end of file |