CO emission spectra for Centaurus A

The observed CO emission spectra in the discovered S1 and S2 shells in the nearby elliptical galaxy, Centaurus A. In both cases, two lines from different molecular states were observed that stand out clearly from the sky noise. The abscissa indicates the velocity (i.e., the radio frequency) and the ordinate the temperature (i.e., the intensity). These diagrammes represent approx. 20 and 30 hours of observation, respectively.