User: bmundim Date: 2011/09/15 03:48 PM

Modified: /trunk/doc/ documentation.tex

Log: Add a few lines about units adopted, in particular the conversion factors for your convenience. Please review these numbers though.

File Changes:

Directory: /trunk/doc/ ======================

File [modified]: documentation.tex Delta lines: +15 -1 =================================================================== --- trunk/doc/documentation.tex 2011-04-21 04:46:32 UTC (rev 40) +++ trunk/doc/documentation.tex 2011-09-15 20:48:00 UTC (rev 41) @@ -132,7 +132,7 @@ a common set of variables by different hydrodynamics codes creates the possibility to share parts of the code, e.g.\ initial data solvers or analysis routines.

-Currently the defined primitive variables are (see~\cite{livrevgrfd} for +Currently the defined primitive variables are (see~\cite{livrevgrrfd} for details): \begin{itemize} \item \verb|rho|: rest mass density $\varrho$ @@ -185,6 +185,8 @@ M_\mathrm{sun} = 1 &;& c = G = 1 \end{eqnarray} which are commonly used in astrophysics and in relativity. +The former sets the mass scale to the solar one and the latter +adopts the same units for time, length and mass.

We assume the following definitions and constants of nature: \begin{eqnarray} @@ -211,6 +213,18 @@ [B] & = & 1/[L]; / \sqrt{\epsilon_0 G / c^2} \end{eqnarray}

+Inserting the SI units into the above unit correspondences, +we find the following conversion factors: +\begin{equation} + M_\mathrm{sun} \equiv 1.477, \mathrm{km} + \equiv 4.92673, \mathrm{\mu s} + \equiv 8.344956\cdot 10^{15}, \mathrm{T}, +\end{equation} +where T (Tesla) is the magnetic field unit in SI, +$1,\mathrm{T}=1,\mathrm{N/(A\cdot m)}$, or in its cgs equivalent, +$1,\mathrm{Tesla} = 10^4,\mathrm{Gauss}$. + + \section{Acknowledgments}

This thorn was produced by Tanja Bode, Roland Haas, Frank L"offler, and Erik Schnetter.