The molecular structure of CRL 618

Phillips, J. P.; Williams, P. G.; Mampaso, A.; Ukita, N.
Bibliographical reference

Astronomy and Astrophysics (ISSN 0004-6361), vol. 260, no. 1-2, p. 283-292.

Advertised on:
7
1992
Number of authors
4
IAC number of authors
2
Citations
15
Refereed citations
13
Description
Spectroscopy and mapping of the type I postmain-sequence source CRL 618, taken with the 45-m antenna of the Nobeyama Radio Observatory and the 12-m NRAO facility at Kitty Peak, are presented. It is shown that the exterior constant velocity envelope has a typical aspect ratio of about 0.8, extends over a range not less than 70 arcsec, and has an FWHM close to about 50 arcsec. Spatial-velocity maps through the nucleus reveal appreciable asymmetries in right ascension, with emission peaking towards about V(lsr) of -25 km/s for easterly offset locations, and about -15 km/s towards the west. These characteristics may arise from a mix of transverse expansion in the bipolar lobes, radial expansion within the outflow cavities, and shock deceleration of the interior H I/H II wind.