The rotating interstellar disc in G35.2–0.74

Maps of NH 3 (1,1) and (2,2) inversion line emission from the molecular cloud G35.2N have been made at 40-arcsec resolution with the 100-m Effelsberg telescope and at 7-arcsec resolution with the VLA. The source is revealed as a large rotating disc, viewed edge-on, of diameter 1.8 pc. Near the centre of this outer structure is a more dense coaxial rotating inner disc (diameter ~0.4 pc, thickness ≦0.08 pc) of mass ~150 M ⊙ . A comparison of the (1,1) and (2,2) emission from the inner disc shows that its average density decreases towards the centre, while its temperature rises from ~25 to >100K. It appears that the inner disc is capable of channelling the bipolar outflow from the central source observed in CO.