We investigated the star formation activities in the AFGL 333 region , which is in the vicinity of the W4 expanding bubble , by conducting NH _ { 3 } ( 1,1 ) , ( 2,2 ) , and ( 3,3 ) mapping observations with the 45 m Nobeyama Radio Telescope at an angular resolution of 75 \arcsec .
The morphology of the NH _ { 3 } ( 1,1 ) map shows a bow-shape structure with the size of 2.0 \times 0.6 pc as seen in the dust continuum .
At the interface between the W4 bubble and the dense NH _ { 3 } cloud , the compact HII region G 134.2+0.8 , associated with IRAS 02245 + 6115 , is located .
Interestingly , just north and south of G 134.2+0.8 we found NH _ { 3 } emission exhibiting large velocity widths of \sim 2.8 km s ^ { -1 } , compared to 1.8 km s ^ { -1 } at the other positions .
As the possibility of mechanical energy injection through the activity of YSO ( s ) is low , we considered the origin of the large turbulent gas motion as indication of interaction between the compact HII region and the periphery of the dense molecular cloud .
We also found expanding motion of the CO emission associated with G 134.2+0.8 .
The overall structure of the AFGL 333-Ridge might have been formed by the expanding bubble of W4 .
However , the small velocity widths observed west of IRAS 02245 + 6115 , around the center of the dense molecular cloud , suggest that interaction with the compact HII region is limited .
Therefore the YSOs ( dominantly Class 0/I ) in the core of the AFGL 333-Ridge dense molecular cloud most likely formed in quiescent mode .
As has been previously suggested for the large scale star formation in the W3 giant molecular cloud , our results show an apparent coexistence of induced and quiescent star formation in this region .
It appears that star formation in the AFGL 333 region has proceeded without significant external triggers , but accompanying stellar feedback environment .