\begin{table}%t3
\caption{\label{met_tab}\label{tab3}Parameters of EVN 6.7~GHz methanol maser features.} 
\small%\centering
\par
\begin{tabular}{ccrrcrrcrrr}
\hline
\hline\noalign{\smallskip}
Feature &  $V_{\rm LSR}$ & \multicolumn{1}{c}{$F_{\rm peak}$} & Var.\tablefootmark{a} & & \multicolumn{1}{c}{$\Delta x$} & \multicolumn{1}{c}{$\Delta y$} &  & \multicolumn{1}{c}{$V_{x}$} & \multicolumn{1}{c}{$V_{y}$} & \multicolumn{1}{c}{$\Delta|V|/|V| $} \\
        &  (km s$^{-1}$) & \multicolumn{1}{c}{(Jy beam$^{-1}$)} & &  & \multicolumn{1}{c}{(mas)} & \multicolumn{1}{c}{(mas)} &  & \multicolumn{1}{c}{(km s$^{-1}$)} & \multicolumn{1}{c}{(km s$^{-1}$)} &                  \\
\hline
\par
1   & 62.11 & 20.62 & 20\% & & $ -106.27\pm0.09 $ & $ 205.81\pm0.13 $ & &       ...        &       ...        & ...  \\
2   & 59.47 & 12.90 & 8\%  & & $           0    $ & $         0     $ & & $ -3.2 \pm 1.0 $ & $ -4.0 \pm 1.4 $ & 25\% \\
3   & 64.13 &  7.88 & 20\% & & $  -72.93\pm0.09 $ & $ 175.07\pm0.13 $ & &       ...        &       ...        & ...  \\
4   & 58.42 &  7.60 & 3\%  & & $   40.35\pm0.09 $ & $ -18.67\pm0.13 $ & & $ -1.7 \pm 1.0 $ & $ -6.1 \pm 1.4 $ & 22\% \\
5   & 63.78 &  7.15 & 35\% & & $ -158.52\pm0.09 $ & $ 135.34\pm0.13 $ & & $ -0.6 \pm 1.0 $ & $ -3.5 \pm 1.4 $ & 40\% \\
6   & 66.06 &  4.15 & 9\%  & & $ -206.96\pm0.09 $ & $ 113.62\pm0.13 $ & & $  1.8 \pm 1.1 $ & $ 11.0 \pm 1.5 $ & 14\% \\
7   & 67.81 &  2.98 & 18\% & & $ -200.44\pm0.08 $ & $ 120.97\pm0.12 $ & & $  0.7 \pm 1.0 $ & $  4.1 \pm 1.4 $ & 35\% \\
8   & 68.52 &  2.42 & 18\% & & $ -198.32\pm0.10 $ & $ 120.56\pm0.14 $ & & $  5.4 \pm 1.2 $ & $  3.3 \pm 1.7 $ & 22\% \\
9   & 63.95 &  2.03 & 17\% & & $  -58.07\pm0.10 $ & $ 177.76\pm0.17 $ & &       ...        &       ...        & ...  \\
10  & 59.91 &  1.77 & 45\% & & $   37.02\pm0.10 $ & $   3.00\pm0.15 $ & & $ -4.2 \pm 1.2 $ & $ -6.1 \pm 1.8 $ & 22\% \\
11  & 64.74 &  1.60 & 32\% & & $ -212.91\pm0.10 $ & $ 125.86\pm0.16 $ & &       ...        &       ...        & ...  \\
12  & 57.02 &  1.20 & 21\% & & $   44.19\pm0.09 $ & $ -24.65\pm0.16 $ & & $ -1.3 \pm 1.2 $ & $ -4.6 \pm 2.0 $ & 41\% \\
13  & 58.42 &  1.16 & 8\%  & & $   20.18\pm0.18 $ & $ -18.57\pm0.46 $ & &       ...        &       ...        & ...  \\
14  & 64.30 &  1.13 & 30\% & & $  -85.95\pm0.10 $ & $ 168.74\pm0.17 $ & &       ...        &       ...        & ...  \\
15  & 57.45 &  0.99 & 10\% & & $ -100.07\pm0.10 $ & $ -52.87\pm0.16 $ & &       ...        &       ...        & ...  \\
16  & 56.84 &  0.87 & 2\%  & & $  -82.83\pm0.11 $ & $ -55.85\pm0.18 $ & & $ -6.3 \pm 1.6 $ & $ -2.4 \pm 2.6 $ & 27\% \\
17  & 62.55 &  0.72 & 44\% & & $ -210.41\pm0.13 $ & $ 101.17\pm0.27 $ & &       ...        &       ...        & ...  \\
18  & 58.51 &  0.56 &...   & & $  -15.95\pm0.22 $ & $   0.44\pm0.33 $ & &       ...        &       ...        & ...  \\
19  & 58.60 &  0.49 &...   & & $   69.45\pm0.19 $ & $ -77.32\pm0.31 $ & &       ...        &       ...        & ...  \\
20  & 61.84 &  0.41 & 25\% & & $ -102.92\pm0.15 $ & $ 189.05\pm0.30 $ & &       ...        &       ...        & ...  \\
21  & 61.76 &  0.40 & 45\% & & $  -81.04\pm0.19 $ & $ 112.36\pm0.46 $ & &       ...        &       ...        & ...  \\
22  & 58.86 &  0.28 & 34\% & & $   -6.48\pm0.18 $ & $ -30.55\pm0.39 $ & &       ...        &       ...        & ...  \\
23  & 64.04 &  0.18 &...   & & $  -68.46\pm0.42 $ & $ 103.02\pm0.58 $ & &       ...        &       ...        & ...  \\
24  & 59.12 &  0.17 &...   & & $   84.43\pm0.39 $ & $ -78.86\pm0.66 $ & &       ...        &       ...        & ...  \\
25  & 60.09 &  0.17 & 10\% & & $  -11.76\pm0.22 $ & $ -25.28\pm0.50 $ & &       ...        &       ...        & ...  \\
26  & 58.68 &  0.16 &...   & & $  -17.03\pm0.63 $ & $ -94.58\pm0.91 $ & &       ...        &       ...        & ...  \\
27  & 59.12 &  0.16 & 17\% & & $   26.70\pm0.24 $ & $ -18.15\pm0.63 $ & &       ...        &       ...        & ...  \\
28  & 58.07 &  0.14 & 19\% & & $ -396.02\pm0.25 $ & $ -39.64\pm0.64 $ & &       ...        &       ...        & ...  \\
29  & 63.07 &  0.13 & 44\% & & $ -213.83\pm0.28 $ & $ 195.95\pm0.63 $ & &       ...        &       ...        & ...  \\
30  & 57.63 &  0.12 &...   & & $  -62.37\pm0.30 $ & $ -57.29\pm0.58 $ & &       ...        &       ...        & ...  \\
31  & 61.76 &  0.12 &...   & & $  -68.25\pm0.42 $ & $  93.82\pm0.77 $ & &       ...        &       ...        & ...  \\
32  & 60.70 &  0.11 &...   & & $ -287.88\pm0.56 $ & $ -43.17\pm0.80 $ & &       ...        &       ...        & ...  \\
33  & 58.77 &  0.09 &...   & & $   -7.14\pm0.97 $ & $  68.86\pm1.10 $ & &       ...        &       ...        & ...  \\
34  & 61.32 &  0.09 & 15\% & & $  -68.81\pm0.33 $ & $ 122.23\pm0.80 $ & &       ...        &       ...        & ...  \\
35  & 63.25 &  0.08 &...   & & $ -157.22\pm0.65 $ & $  33.89\pm1.01 $ & &       ...        &       ...        & ...  \\
36  & 63.51 &  0.08 &...   & & $ -209.00\pm0.54 $ & $ 104.94\pm1.03 $ & &       ...        &       ...        & ...  \\
37  & 63.69 &  0.08 &...   & & $ -149.29\pm0.55 $ & $  90.60\pm0.57 $ & &       ...        &       ...        & ...  \\
38  & 52.89 &  0.07 &...   & & $ -407.11\pm0.65 $ & $ 669.44\pm1.07 $ & &       ...        &       ...        & ...  \\
39  & 56.84 &  0.06 &...   & & $  -91.01\pm0.95 $ & $-124.54\pm1.31 $ & &       ...        &       ...        & ...  \\
\par
 & & & & & & & & & &\\
0     &        &       &      & & $ -84.71 \pm 0.06$ & $ 67.90 \pm 0.10$ & &  $   0  $  &   $   0  $  & \\
\hline
\multicolumn{10}{c}{Reference Feature: Absolute position}\\
\hline \noalign{\smallskip}
Feature & \multicolumn{4}{c}{RA(J2000)} & \multicolumn{4}{c}{ Dec(J2000) } & & \\
        & \multicolumn{4}{c}{(h m s)}     & \multicolumn{4}{c}{(\degr $'$ $''$)}  & & \\
\hline 
2 &\multicolumn{4}{c}{18:21:09.13711~$\pm$~0.00023}&\multicolumn{4}{c}{$-$14:31:48.6853~$\pm$~0.0036} & & \\
\hline 
\end{tabular}
\tablefoot{For each identified feature, the label (given in Col.~1) increases with decreasing brightness.
Columns~2,~3, and~4 report the LSR velocity and brightness of the brightest spot and its percent brightness
variability. Columns~5 and~6 give the position offset relative to the feature~\#~2, in the east and north directions, respectively.
Columns~7 and~8 report the projected components of the feature proper motion relative to the center of motion (as defined in Sect.~\ref{ch3oh_results}, and identified with label~\#~0), along the east and north directions, respectively.
Column~9 shows the relative error of the proper motion amplitude.
The absolute position of the reference feature~\#~2 is reported at the bottom of the table.\\%[-1.5mm]
\tablefoottext{a}{Variability (\%) = ($F_{\rm MAX} -  F_{\rm MIN}$ of the brightest spot) / (($F_{\rm MAX}  + F _{\rm MIN}$)/2.0)}.}
\end{table}