  We present the results of NH3 (1,1), (2,2) and (3,3) and H2O maser
simultaneous mapping observations toward the high-mass star-forming region W33
with the Nobeyama 45-m radio telescope. W33 has six dust clumps and one of
which, W33 Main, is associated with a compact HII region. To investigate
star-forming feedback activity on its surroundings, the spatial distribution of
the physical parameters was established. The distribution of the rotational
temperature shows a systematic change from west to east in our observed region.
The high-temperature region obtained in the region near W33 Main is consistent
with interaction between the compact HII region and the periphery molecular
gas. The size of the interaction area is estimated to be approximately 1.25 pc.
NH3 absorption features are detected toward the centre of the HII region.
Interestingly, the absorption feature was detected only in the NH3 (1,1) and
(2,2) transitions, with no absorption feature seen in the (3,3) transition.
These complex profiles in NH3 are difficult to explain by a simple model and
may suggest that the gas distribution around the HII region is highly
complicated.
