\begin{table}%t11 \par \caption{\label{table:parameters}Projected rotational velocity, temperature, surface gravity, mass and age of T~dwarfs.} %%\centerline { \begin{tabular}{l c c c c c c c c c c} % 5 columns \hline\hline Object & Spectral type & $v_{\rm rot} \sin i$ & $\langle T_{\rm eff}\rangle$ & Prev. & Ref. & $\langle \log g\rangle$ & Prev. & Ref. & $M$ & Age \\ & & {km~s$^{-1}$} & {K} & {K} & & {(cm s$^{-2}$)} & {(cm s$^{-2}$)} & & $M_{\rm J}$ & {Gyr} \\ \hline \object{SDSSp J125453.90-012247.4} & T2 & 34 $\pm$ 7 & 2007 $\pm$ 662 & 1200 & 1 & 4.3 $\pm$ 1.0 & 5.0 & 1 & -- & -- \\ \object{2MASS J05591914-1404488} & T4.5 & 28 $\pm$ 5 & 1002 $\pm$ 278 & 1200 & 1 & 4.9 $\pm$ 0.8 & 5.5 & 1 & $30^{\rm +45}_{-23}$ & $1.0^{\rm +9}_{-0.9}$ \\[0.3mm] \object{2MASS J15031961+2525196} & T5 & 36 $\pm$ 5 & 1009 $\pm$ 217 & 1178 & 2 & 4.6 $\pm$ 0.8 & $\approx$5.0 & 5 & $18^{\rm +37}_{-13}$ & $0.4^{\rm +4.6}_{-0.3}$ \\[0.3mm] \object{SDSS J162414.37+002915.6} & T6 & 42 $\pm$ 5 & 980 $\pm$ 163 & 1002$^{\rm +98}_{86}$ & 3 & 4.8 $\pm$ 0.7 & $\approx$5.0 & 5 & $23^{\rm +52}_{-16}$ & $0.6^{\rm +9.4}_{-0.5}$ \\[0.3mm] \object{SDSS J134646.45-003150.4} & T6.5 & 16 $\pm$ 5 & 990 $\pm$ 107 & 960--1020 & 4 & 4.1 $\pm$ 0.4 & 5.0--5.2 & 4 & $10^{\rm +10}_{-5}$ & $0.1^{\rm +0.4}_{-0.08}$ \\[0.3mm] \object{2MASS J15530228+1532369} & T7 & 30 $\pm$ 7 & 941 $\pm$ 138 & 893 & 2 & 4.6 $\pm$ 0.6 & $\approx$5.0 & 5 & $18^{\rm +30}_{-11}$ & $0.4^{\rm +3.6}_{-0.3}$ \\[0.3mm] \object{2MASS J12171110-0311131} & T7.5 & 29 $\pm$ 7 & 922 $\pm$ 103 & 860--880 & 4 & 4.8 $\pm$ 0.7 & 4.7--4.9 & 4 & $23^{\rm +52}_{-16}$ & $0.8^{\rm +9}_{-0.7}$ \\[0.3mm] \object{GL 570D} & T7.5 & 32 $\pm$ 8 & 948 $\pm$ 53 & 780--820 & 4 & 4.5 $\pm$ 0.5 & 5.1 & 4 & $15^{\rm +15}_{-9}$ & $0.3^{\rm +1.7}_{-0.2}$ \\[0.3mm] \object{2MASS J04151954-0935066} & T8 & 36 $\pm$ 7 & 947 $\pm$ 79 & 740--760 & 4 & 4.3 $\pm$ 0.7 & 4.9--5.0 & 4 & $10^{\rm +20}_{-6}$ & $0.1^{\rm +1.9}_{-0.09}$ \\ \hline \end{tabular}} \par \medskip $^1$ Cushing et~al. (\cite{Cushing08}). $^2$ Estimated $T_{\rm eff}$ derived from the $T_{\rm eff}$-spectral type relation in Looper et~al. (\cite{Looper08}). $^3$ Vrba et~al. (\cite{Vrba04}). $^4$ Burgasser et~al. (\cite{Burgasser06}a). $^5$ Knapp et~al. (\cite{Knapp04}). \end{table}