\begin{table}%t2
%\centering
\par
\caption{\label{Tab:assum}Parameters adopted for the performance simulations.}
\small  \begin{tabular}{l l}
    \hline  \hline
    Parameter &  \\
    \hline
Configuration & Emma X-Array Design with a 6:1 aspect ratio (see Table~\ref{Tab:darwin_spec})\\
Planet & Earth-sized planet with a constant temperature of 265~K across the habitable zone  \\
Exozodiacal density & Three times our solar system, based on Kelsall model \citep{Kelsall:1998} \\
Mission duration & 5~years (2~years for survey and 3~years for characterisation)\\
    Retargeting time & 6~h \\
    Integration efficiency & 70\% (accounting for overhead loss)\\
    Target stars & Darwin All Sky Survey Catalogue (DASCC, \citealt{Kaltenegger:2008})\\
    Earth-like planet per star ($\eta_\oplus$) & 1 \\
    Habitable zone & 0.7--1.5~AU scaled with $L^{1/2}_\star$ \\
    Time allocation & 10\% F, 50\% G, 30\% K and 10\% M stars\\
    Array rotation period & 50~000~s (not scaled with the array baseline length) \\
    $SNR$ threshold for detection & 5 \\
    $SNR$ threshold for spectroscopy & 5 (CO$_2$,O$_3$) and 10 (CO$_2$,O$_3$,H$_2$O) \\
    \hline
  \end{tabular}
\end{table}