\begin{table}%T1 \caption{Atmospheric parameters of PG~1325+101 derived from spectroscopy.\label{cap:spectro}} %\centerline {\small \begin{tabular}{llll} \hline\hline Source & $T_{\rm eff}$ (K) & $\log g$ & $\log N($He$)/N($H$)$ \\ \hline Telting \& {\O}stensen (2004) & 34~800 $\pm$ 390 & $5.81 \pm 0.05$ & $-1.65 \pm 0.02$ \\ This work (PB6) & 34~890 $\pm$ 525 & $5.84 \pm 0.09$ & $-1.74 \pm 0.07$ \\ This work (BG9) & 35~090 $\pm$ 450 & $5.81 \pm 0.08$ & $-1.71 \pm 0.05$ \\ This work (MMT1) & 35~420 $\pm$ 390 & $5.78 \pm 0.05$ & $-1.68 \pm 0.02$ \\ \hline Mean$^{\dag}$ & 35~050 $\pm$ 220$^{\ddag}$ & $5.81 \pm 0.04$$^{\ddag}$ & $-1.70 \pm 0.02$$^{\ddag}$ \\ \hline \end{tabular}} \smallskip $^{\dag}$ Reference values used for the asteroseismic analysis. $^{\ddag}$ The given error is the quadratic combination of the uncertainties of each measurement. \end{table}