We report the discovery of a massive SCUBA core with evidence of inflow and outflow motions .
This core is detected by SCUBA at both 450 and 850 \mu m. Barely resolved by the telescope beam at 450 \mu m , it has a size of 10″ , corresponding to 0.28 pc at a distance of 5.7 kpc .
The dust temperature is estimated to be \leq 29 K , the total mass is 820 M _ { \sun } and the average density is 1.1 \times 10 ^ { 6 } cm ^ { -3 } in a region with a radius of 5″ .
Follow-up spectral line observations , including HCN ( 3 - 2 ) , HCO ^ { + } ( 3 - 2 ) , H ^ { 13 } CO ^ { + } ( 3 - 2 ) and C ^ { 17 } O ( 2 - 1 ) reveal a typical blue profile which indicates that this core is collapsing .
The CO ( 3 - 2 ) line profile is as broad as 38 km/s , indicating outflow motions in this region .
This core is approximately 1.5 pc away from the known HII region G25.4NW , but there are no obvious radio , IRAS , MSX or Spitzer sources associated with it .
We suggest that this core is at a very early stage of massive star or cluster formation .