McCarthy et al. have used the Australia Telescope Compact Array (ATCA)
to conduct observations of the 36.2 GHz methanol transition towards
the nearby active galaxy NGC 4945. These observations have led to a
more accurate determination of the offset between the maser emission
and the nucleus of NGC 4945 with a typical synthesised beam of 6
arcseconds × 4 arcsecond (corresponding to 350 x 235 light-years).
Other transitions of methanol, and spectral lines of other molecular
species were also obtained, including strong detections of HC3N and
CS. The image above shows the 36.2 GHz spectrum from the region of
peak emission, revealing several spectral features: the 55 mJy primary
component has a velocity of 673 km/s, redshifted with respect to the
systemic velocity of NGC 4945 of 585 km/s, with two significantly
lower flux density (∼15 mJy) components at 643 and 705 km/s.
Full results
are published in the Monthly Notices of the Royal Astronomical Society
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