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===Corrected Logic=== Taking all of the above into consideration, the expressions that should be used to convert from Dominic's code units to real units are the following: <table border="1" align="center" cellpadding="8"> <tr> <td colspan="1" align="center"> <font color="blue"><b>General Relations (taking {{Math/MP_MeanMolecularWeight}} into account)</b></font> </td> </tr> <tr><td align="center"><table border="0" cellpadding="3" cellspacing="10"> <tr> <td align="right"> <math> \frac{T_\mathrm{cgs}}{T_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> \frac{c^2}{(\Re/\bar{\mu})} \biggl( \frac{\tilde{r}}{\tilde{c}^2} \biggr) </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> 1.083\times 10^{13}~\mathrm{K} \biggl( \frac{\tilde{r} \bar{\mu}}{\tilde{c}^2} \biggr) </math> </td> </tr> <tr> <td align="right"> <math> \frac{\ell_\mathrm{cgs}}{\ell_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> \frac{\Lambda}{ c^2 \bar{\mu}^2} \biggl( \frac{\tilde{c}^4 \tilde{g} \tilde{a} }{\tilde{r}^4} \biggr)^{1/2} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> 3.418\times 10^{5}~\mathrm{cm} \biggl( \frac{\tilde{c}^4 \tilde{g} \tilde{a} }{\tilde{r}^4 \bar{\mu}^4} \biggr)^{1/2} </math> </td> </tr> <tr> <td align="right"> <math> \frac{t_\mathrm{cgs}}{t_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> \frac{\Lambda}{ c^3 \bar{\mu}^2} \biggl( \frac{\tilde{c}^6 \tilde{g} \tilde{a} }{\tilde{r}^4} \biggr)^{1/2} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> 1.139\times 10^{-5}~\mathrm{s} \biggl( \frac{\tilde{c}^6 \tilde{g} \tilde{a} }{\tilde{r}^4 \bar{\mu}^4} \biggr)^{1/2} </math> </td> </tr> <tr> <td align="right"> <math> \frac{m_\mathrm{cgs}}{m_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> \frac{\Lambda}{ G \bar{\mu}^2} \biggl( \frac{\tilde{g}^3 \tilde{a} }{\tilde{r}^4} \biggr)^{1/2} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> 4.609\times 10^{33}~\mathrm{g} \biggl( \frac{\tilde{g}^3 \tilde{a} }{\tilde{r}^4 \bar{\mu}^4} \biggr)^{1/2} </math> </td> </tr> </table></td></tr> </table> Hence, for Dominic's first simulation ('''Case A'''), the following conversions apply. <table border="1" align="center" cellpadding="8"> <tr> <td colspan="1" align="center"> <b>Case A</b>:<br /> <math>\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> </td> </tr> <tr><td align="center"><table border="0" cellpadding="3" cellspacing="10"> <tr> <td align="right"> <math> \frac{T_\mathrm{cgs}}{T_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> 1.083\times 10^{13}~\mathrm{K} \biggl[ \frac{0.44 (4/3)}{198^2} \biggr] </math> </td> <td align="left"> <math>= 1.621\times 10^8~\mathrm{K}</math> </td> </tr> <tr> <td align="right"> <math> \frac{\ell_\mathrm{cgs}}{\ell_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> 3.418\times 10^{5}~\mathrm{cm} \biggl[ \frac{198^4 (0.044) }{(0.44)^4 (4/3)^4} \biggr]^{1/2} </math> </td> <td align="left"> <math>= 8.167\times 10^9~\mathrm{cm}</math> </td> </tr> <tr> <td align="right"> <math> \frac{t_\mathrm{cgs}}{t_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> 1.139\times 10^{-5}~\mathrm{s} \biggl[ \frac{198^6 (0.044) }{(0.44)^4 (4/3)^4} \biggr]^{1/2} </math> </td> <td align="left"> <math>= 5.334\times 10^1~\mathrm{s}</math> </td> </tr> <tr> <td align="right"> <math> \frac{m_\mathrm{cgs}}{m_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> 4.609\times 10^{33}~\mathrm{g} \biggl[ \frac{ 0.044 }{(0.44)^4 (4/3)^4} \biggr]^{1/2} </math> </td> <td align="left"> <math>= 2.809\times 10^{33}~\mathrm{g}</math> </td> </tr> </table></td></tr> <tr><td align="center"><table border="0" cellpadding="3" cellspacing="10"> <tr> <td align="right"> <math> \frac{\rho_\mathrm{cgs}}{\rho_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> \biggl( \frac{m_\mathrm{cgs}}{m_\mathrm{code}} \biggr) \biggl( \frac{\ell_\mathrm{cgs}}{\ell_\mathrm{code}} \biggr)^{-3} </math> </td> <td align="left"> <math>= 5.157\times 10^{3}~\mathrm{g}~\mathrm{cm}^{-3}</math> </td> </tr> <tr> <td align="right"> <math> \frac{\kappa_\mathrm{cgs}}{\kappa_\mathrm{code}} </math> </td> <td align="center"> <math> = </math> </td> <td align="left"> <math> \biggl( \frac{\ell_\mathrm{cgs}}{\ell_\mathrm{code}} \biggr)^{2} \biggl( \frac{m_\mathrm{cgs}}{m_\mathrm{code}} \biggr)^{-1} </math> </td> <td align="left"> <math>= 2.375\times 10^{-14}~\mathrm{cm}^2~\mathrm{g}^{-1}</math> </td> </tr> </table></td></tr> </table> When using the above tabulated '''Case A''' conversion units, it must be understood that the "code unit" values refer to units used in Dominic's rad-hydro code. But it should also be appreciated, as discussed above, that the initial model provided to Dominic by Wes — which had been generated by the SCF code — used a different unit of length from Dominic. The conversion factor from SCF-code lengths to the length's used in Dominic's code is: <div align="center"> <math> \frac{\ell_\mathrm{code}}{\ell_\mathrm{SCF}} = \biggl[ \frac{\pi (128-3)}{128} \biggr] = 3.068 . </math> </div> <span id="Q0.7properties">Hence, beginning with the values of various binary system parameters [http://www.phys.lsu.edu/~tohline/clayton/q07.pdf as generated by the SCF code], we conclude that the initial model used by Dominic in his '''Case A''' rad-hydro simulations has the following properties:</span> <table align="center" border="1" cellpadding="5"> <tr> <td align="center" colspan="5"> '''Properties of Initial Q0.7 Polytropic Binary''' </td> </tr> <tr> <td align="center"> Quantity </td> <td align="center"> SCF-code<br/> Value </td> <td align="center"> Conversion<br/> Factor </td> <td align="center"> RadHydro-code<br/> Value </td> <td align="center"> '''Case A'''<br/> physical units </td> </tr> <tr> <td align="center"> <math>M_\mathrm{Accretor}</math> </td> <td align="center"> <math>0.01394</math> </td> <td align="center"> <math>\biggl( \frac{\ell_\mathrm{code}}{\ell_\mathrm{SCF}} \biggr)^{3}</math> </td> <td align="center"> <math>0.4025</math> </td> <td align="center"> <math>0.565~M_\odot</math> </td> </tr> <tr> <td align="center"> <math>M_\mathrm{Donor}</math> </td> <td align="center"> <math>0.009761</math> </td> <td align="center"> <math>\biggl( \frac{\ell_\mathrm{code}}{\ell_\mathrm{SCF}} \biggr)^{3}</math> </td> <td align="center"> <math>0.2819</math> </td> <td align="center"> <math>0.396~M_\odot</math> </td> </tr> <tr> <td align="center"> <math>\rho_\mathrm{Accretor}</math> </td> <td align="center"> <math>1.000</math> </td> <td align="center"> <math>1</math> </td> <td align="center"> <math>1.000</math> </td> <td align="center"> <math>5.16\times 10^{3}~\mathrm{g}~\mathrm{cm}^{-3}</math> </td> </tr> <tr> <td align="center"> <math>a_\mathrm{separation}</math> </td> <td align="center"> <math>0.8394</math> </td> <td align="center"> <math>\biggl( \frac{\ell_\mathrm{code}}{\ell_\mathrm{SCF}} \biggr)</math> </td> <td align="center"> <math>2.575</math> </td> <td align="center"> <math>0.300~R_\odot</math> </td> </tr> <tr> <td align="center"> <math>P_\mathrm{orbit}</math> </td> <td align="center"> <math>31.19</math> </td> <td align="center"> <math>1</math> </td> <td align="center"> <math>31.19</math> </td> <td align="center"> <math>27.7~\mathrm{min}</math> </td> </tr> </table>
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