\begin{table}%t1 \caption{List of symbols.} %\begin{center} \par \begin{tabular}{lp{0.75\hsize}} \hline\hline Symbol & Description\\ \hline $\chi$ & Polarization angle (N through E)\\ $\chi_0$& Polarization angle at $\lambda = 0$\\ $\nu$ & Frequency\\ $\delta\nu$ & Channel width in frequency\\ $\nu_{\rm c}$ & Central frequency of a channel\\ $\lambda$ & Wavelength\\ $\lambda_0$ & Wavelength to which all polarization vectors are derotated\\ $\lambda_{\rm c}^2$& Central wavelength squared of a channel\\ $\delta\lambda^2$ & Channel width in wavelength squared\\ $\Delta\lambda^2$ & Total bandwidth in wavelength squared. $\Delta\lambda^2 = \lambda^2_{\rm max} - \lambda^2_{\rm min}$\\ $\phi$ & Faraday depth\\ $\delta\phi$ & FWHM of the main peak of the RMTF\\ $\mbox{RM}$ & Rotation measure\\ $W(\lambda^2)$ & Weight function\\ $w_i$ & Weight of the $i$th data point\\ $K$ & One over the integral of $W$ or one over the sum of weights\\ $F(\phi)$ & Faraday dispersion function without spectral dependence\\ $\tilde{F}(\phi)$ & Reconstructed approximation to $F(\phi)$\\ $F(\phi, \lambda^2)$ & General form of the Faraday dispersion function\\ $f(\phi)$ & $F(\phi,\lambda^2)/s(\lambda^2)$\\ $s(\lambda^2)$ & Spectral dependence in $I$, normalized to unity at $\lambda^2 = \lambda^2_0$\\ $\alpha$ & Frequency spectral index\\ $P(\lambda^2)$ & Complex polarized surface brightness\\ $\tilde{P}(\lambda^2)$ & Observed $P$: $W(\lambda^2)P(\lambda^2)$\\ $p(\lambda^2)$ & Complex polarization fraction $P(\lambda^2)/I(\lambda^2)$\\ $R(\phi)$ & Rotation Measure Transfer Function (RMTF)\\ $\vec{B}$ & Magnetic induction\\ $\vec{r}$ & Position vector\\ $n_{\rm e}$& Thermal electron density\\ $\gamma$ & Spectral index of the relativistic electron energy distribution\\ $\Re z$ & Real part of $z$\\ $\Im z$ & Imaginary part of $z$\\ $\rho$ & Merit function for traditional linear least squares fitting of rotation measures. Defined in Eq.~(\ref{brentjens_eqn:rho})\\ $\sigma$ & rms noise in a single channel map\\ $\sigma_{\rm Q}$, $\sigma_{\rm U}$ & rms noise in single $Q$ or $U$ channel maps\\ $\sigma_{\rm P}$, $\sigma_\chi$ & Standard error of $\|P\|$ and $\chi$ in individual channel maps\\ $\sigma_\phi$, $\sigma_{\chi_0}$ & Standard error in Faraday depth and position angle at $\lambda=0$\\ $\sigma_{\lambda^2}$ & Standard deviation of the distribution of $\lambda^2$ values that are sampled. This is a measure of the effective width of the $\lambda^2$ sampling\\ $\delta(x)$ & Dirac delta function\\ \hline \end{tabular} %\end{center} \par \label{brentjens_tab:list_of_symbols} \end{table}