Astron. Astrophys. 346, 441-452 (1999)

5. The molecular outflow

Fig. 5 shows a map of the integrated CO flux in the vicinity of Holoea. We have also included contours of the V image, to show the location of the stars and the IRAS 60 µm image, deconvolved using the Groningen HIRAS routine (Bontekoe et al., 1994). The heavy IRAS contour is chosen to mark the FWHM of the IRAS source, while the thin IRAS contour is close to the sky level and shows the outer limits of this IRAS point source. The brightest CO feature in the map is coincident with the location of Holoea, but fainter extended emission is seen in a region of . The CO emission in the vicinity of Holoea has the largest velocity dispersion, as well as the strongest emission. The bright CO source associated with Holoea is clearly associated with a larger, fainter CO cloud.

Fig. 5. Integrated CO J = 2-1 map. The CO emission is integrated from -14.5 - -34.7 km s-1 and is shown in grey scale for the range 15 - 40 K km s-1. The thin black contours are from the V band image. The thick black and thin grey contours are the IRAS 60 µm flux densities. Holoea lies directly at the center of the IRAS source. This image is 3:06 6:03, North up, East left.

Fig. 6 shows the V image with contours from redshifted and blue-shifted CO maps. The grey contours show the redshifted components, while the black contours show the blue-shifted ones. For both red and blue-shifted contours, the heavy contours have a high velocity relative to the system rest velocity, while the light contours have a low relative velocity. The velocity ranges and the flux levels for the contours are listed in Table 3. In the immediate vicinity of Holoea, there is a pattern suggestive of a bipolar outflow: the red and blue-shifted contours are displaced to opposite sides of the central star. The direction of the outflow appears to be in roughly the same direction as the direction of the lowest extinction seen in Sect. 4, generally West of North.

Fig. 6. CO J = 2-1 velocity contours overlayed on a V image. The grey lines are redshifted CO emission, while the black lines are blue-shifted CO emission. In both cases, the thick lines have a high velocity relative to the system and the thin lines have a low relative velocity. Table 3 gives the exact velocity ranges and flux levels for the contours. Same scale as Fig. 5.

Table 3. CO contour levels in Fig. 6

© European Southern Observatory (ESO) 1999

Online publication: May 21, 1999
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