Summary of Scalings
On an accompanying Wiki page we have explained how to interpret the set of dimensionless units that Dominic Marcello is using in his rad-hydrocode. The following table summarizes some of the mathematical relationships that have been derived in that accompanying discussion.
General Relation
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Case A:
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<math>
f_\mathrm{Edd} \equiv \frac{L_\mathrm{acc}}{L_\mathrm{Edd}}
</math>
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<math>
=
</math>
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<math>
1.25\times 10^{21} \biggl( \frac{\tilde{g}^{1/2} \tilde{r}^2 \bar{\mu}^2 }{\tilde{c}^5 \tilde{a}^{1/2}} \biggr) \biggl[ \frac{\dot{M}}{R_a} \biggr]_\mathrm{code}
</math>
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<math>= ~~6.74\times 10^9 \biggl[ \frac{\dot{M}}{R_a} \biggr]_\mathrm{code}</math>
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<math>
\frac{\rho_\mathrm{threshold}}{\rho_\mathrm{max}} \equiv \frac{1}{\rho_\mathrm{max}\kappa_\mathrm{T} (\Delta R)}
</math>
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<math>
=
</math>
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<math>
5.164\times 10^{-21}~\biggl( \frac{\tilde{c}^4 \tilde{a}^{1/2}}{\bar{\mu}^2 \tilde{r}^2 \tilde{g}^{1/2}} \biggr) \biggl[ \frac{1}{\rho_\mathrm{max}(\Delta R)} \biggr]_\mathrm{code}
</math>
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<math>=~~ 4.83\times 10^{-12}</math>
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<math>
\Gamma \equiv \frac{P_\mathrm{gas}}{P_\mathrm{rad}}
</math>
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<math>
=
</math>
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<math>
3 \biggl( \frac{\tilde{r}}{\bar{\mu} \tilde{a}} \biggr) \biggl[ \frac{ \rho }{T^3} \biggr]_\mathrm{code}
</math>
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<math>= ~~22.5 \biggl[ \frac{ \rho }{T^3} \biggr]_\mathrm{code}</math>
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<math>
\frac{v_\mathrm{circ}}{c} \equiv \frac{2\pi a_\mathrm{separation}}{c P_\mathrm{orbit}}
</math>
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<math>
=
</math>
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<math>
\frac{2\pi}{\tilde{c}} \biggl[\frac{a_\mathrm{sep}}{P_\mathrm{orb}}\biggr]_\mathrm{code}
</math>
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<math>= ~~0.032 \biggl[\frac{a_\mathrm{sep}}{P_\mathrm{orb}}\biggr]_\mathrm{code}</math>
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Case A
<math>\Rightarrow ~~~\tilde{g} = 1</math>; <math>\tilde{c} = 198</math>; <math>\tilde{r} = 0.44</math>; <math>\tilde{a} = 0.044</math>; <math>\bar\mu = 4/3</math>; <math>\rho_\mathrm{max} = 1</math>; <math>(\Delta R) = \frac{\pi}{128}</math>
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Combining the above Case A relations with the RadHydro-code properties of the Q0.7 polytropic binary that serves as an initial condition for Dominic's simulations, we conclude the following: