# High-Resolution Radio Observations of Five Optically Selected Type 2 [PERSON]
## 2 Sample Selection and Observing Goals  
We selected five sources for mas-resolution follow-up VLBI observations from the sample of [11]. Our target sources are listed in Table 1. These were previously observed in the radio at 8.4 GHz with the VLA in its B configuration [11], providing typical angular resolution of about 1 arcsec or somewhat below. Originally, the sources were taken from the optically selected sample of [PERSON] et al. [23], which was the first comprehensive survey for studying the optical properties of Type 2 quasars (i.e., quasars where the accretion disk is seen nearly \"edge-on\", and the disk and the broad-line region are obscured by the surrounding torus of dense gas and dust) in detail using SDSS data. Each of the five sources we selected (Table 1) showed symmetric double radio structure on arcsec angular scales in the 8.4-GHz VLA images, and their overall radio spectra were reported to be inverted [11]. Two of our targets, J0741+3020 and J0956+5735, were included in the sample of [PERSON] et al. [24], who looked for ionized gas outflows in obscured quasars. According to their optical spectroscopic observations, outflows are detected in both objects. J0741+3020 is associated with a giant (\(>\)100 kpc) ionized nebula, while in the case of J0956+5735, the compact [OIII] profile suggests a spatially unresolved outflow [24]. The host galaxies of three of these AGNs are morphologically classified from SDSS or _Hubble Space Telescope_ images as bulge-dominated elliptical/S0 galaxies (Table 1), with J0741+3020 as an ULIRG elliptical in a multiple system [24; 25]. J1447+0211 is difficult to classify as it appears highly disturbed due to a recent galaxy interaction [26]. It shows optical features such as tidal tails, bridge, and even double nuclei with 1.5 kpc separation. For the host galaxy of J1026\(-\)0042, no classification is found in the literature. Our sources selected for VLBI observations (Table 1) fall in the radio-intermediate regime, between the radio-quiet and radio-loud AGNs. Interestingly, most of the sources in the 8.4-GHz VLA sample [11] with flat or inverted spectra are radio-intermediate objects, and some of them show extended symmetric double structure on arcsec scale. A flat/inverted spectrum may indicate free-free absorption by ionized gas in the narrow-line region. This finding was rather unusual, which prompted us to probe the structure of our sub-sample of \"best established\" symmetric sources (Table 1) on mas scales with VLBI observations. Finding a mas-scale compact radio core with deep VLBI imaging could in principle pin down the location of the AGN, which has been found offset from the optical position in a number of cases (e.g., [8]), while the extended radio emission should be completely resolved out (undetected) on the long interferometer baselines. Although an unlikely scenario for the given sample, \begin{table}
\begin{tabular}{l c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**ID**} & \multicolumn{2}{c}{**Right Ascension**} & \multicolumn{2}{c}{**Declination**} & \multicolumn{2}{c}{**S\({}_{\bf 8.4\,GHz}\)**} & \(\mathbf{\kappa_{\bf 8.4}\,\mathbf{r}\)**} & \multicolumn{1}{c}{**Host**} \\  & **h** & **min** & **s** & \(\circ\) & \(\mathbf{r}\) & \(\mathbf{\prime\prime}\) & **z** & **mJy** & \(\mathbf{\kappa_{\bf 1.4}}\) & **mag** & **Galaxy** \\ \hline SDSS J0741\(+\)3020 & 07 & 41 & 30.513 & \(+\)30 & 20 & 05.186 & 0.476 & 2.97 & \(+\)0.56 & 21.06 & ULIRG \\ SDSS J0956+5735 & 09 & 56 & 29.058 & \(+\)57 & 35 & 08.775 & 0.361 & 2.88 & \(+\)0.72 & 20.18 & E/S0 \\ SDSS J1014+0244 & 10 & 14 & 03.524 & \(+\)02 & 44 & 16.521 & 0.573 & 4.53 & \(+\)0.45 & 21.51 & E/S0 \\ SDSS J1026\(-\)0042 & 10 & 26 & 40.437 & \(-\)00 & 42 & 06.484 & 0.364 & 3.68 & \(+\)0.38 & 19.73 &... \\ SDSS J1447+0211 & 14 & 47 & 11.292 & \(+\)02 & 11 & 36.234 & 0.386 & 2.76 & \(+\)0.85 & 20.35 & HD \\ \hline \hline \end{tabular}
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