Astron. Astrophys. 345, L43-L46 (1999)

3. Results

Fig. 1 shows a contour map of the mm continuum emission toward I20126. The emission is unresolved and the peak position, as determined from gaussian fitting is , , coincident with that of the mm continuum measured by Cesaroni et al. (1997). The total flux density is mJy.

Fig. 1. Contour plot of the mm continuum emission toward I20126 (solid contours). Contour levels are 1.5 to by mJy beam-1. The dashed contours show the continuum emission at cm with contour levels 0.03 to by mJy beam-1. The filled triangles mark the position of the GHz H2O masers from Tofani et al. (1995).

In the lower panel of Fig. 2 we show our uniformly weighted cm continuum map in solid contours. We also show the position of the water masers measured by Tofani et al. (1995) as triangles and the peak positions of fits to channel maps of CH₃CN(5-4) from Cesaroni et al. (1997) as circles. The cm continuum emission consists of two clearly distinct sources, the northern one being coincident with H₂O masers, CH₃CN and mm continuum emission. Both sources are clearly resolved along their major axis, and appear to be aligned in the same direction with a position angle of 117^o. This orientation is identical to the direction of the bipolar molecular flow imaged in the HCO⁺(1-0) transition by Cesaroni et al. (1997), which is shown in the upper panel. The H₂O masers are coincident with the northern continuum source and are also aligned along this same angle. On the other hand the structure seen in CH₃CN is oriented perpendicular to the cm continuum emission.

Fig. 2. Top panel: The bipolar molecular flow in I20126. Blue- and red-shifted HCO+(1-0) emission is shown in solid and dashed contours respectively. Emission from the H2 S(0) vibrational line at m is shown in grey scale (see Cesaroni et al. 1997for details). H2O masers are shown as filled triangles and the box shows the area seen enlarged below. Bottom Panel: cm continuum emission (contours) with levels 0.05 to by mJy beam-1. The filled triangles mark the position of H2O masers and the open circles mark the peak position of gaussian fits to channel maps of the CH3CN(5-4) transition. The synthesized beam is shown in the bottom right corner.

In our uniformly weighted map we measure cm flux densities of about mJy and mJy for the northern and southern components respectively. The northern component appears double peaked and can be well fitted with two unresolved sources of similar flux density. The southern component has a single peak; a 2-D gaussian fit shows that it is unresolved along the minor axis and has a deconvolved size of along its major axis.

We also searched for cm continuum emission at the position of the sources detected in the H₂ NIR lines by Ayala et al. (1998). No additional sources where found with a limit of Jy beam^-1.

© European Southern Observatory (ESO) 1999

Online publication: April 28, 1999
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