Molecules in boldface are new detections in M 82.

Some molecules do not have a wide enough dynamic range in energy to calculate the rotational temperature with precision. For them, we assumed T_rot = 20 ± 10 K (see Sect. 3.4 and Appendix A for details).

Some extra detections observed by Aladro et al. (2011) were used. CS shows two components with different column densities and rotational values corresponding to the two fits that result from its Boltzmann diagram. The fractional abundance value is in this case  [N_CS(1) + N_CS(2)] /N_C³⁴S. The molecules shown at the bottom of the table were observed by:

Martín et al. (2009a);

Fuente et al. (2005) (averaged value for the galaxy disk);

Hüttemeister et al. (1995) (averaged value for the nuclear zone);

Fuente et al. (2006);

Aladro et al. (in prep.).

Only upper limits were reported until now: SO, and SO₂ by Petuchowski & Bennett (1992), and H¹³CN by Wild et al. (1990).