We present results from JHKs imaging of the densest region of the W49 molecular cloud .
In a recent paper ( [ Alves & Homeier 2003 ] ) , we reported the detection of ( previously unknown ) massive stellar clusters in the well-known giant radio HII region W49A , and here we continue our analysis .
We use the extensive line-of-sight extinction to isolate a population of objects associated with W49A .
We constrain the slope of the stellar luminosity function by constructing an extinction-limited luminosity function , and use this to obtain a mass function .
We find no evidence for a top-heavy MF , and the slope of the derived mass function is -1.6 \pm 0.3 .
We identify candidate massive stars from our color-magnitude diagram , and we use these to estimate the current total stellar mass of 5 - 7 \times 10 ^ { 4 } M _ { \odot } in the region of the W49 molecular cloud covered by our survey .
Candidate ionizing stars for several ultra-compact HII regions are detected , with many having multipe candidate sources .
On the global molecular cloud scale in W49 , massive star formation apparently did not proceed in a single concentrated burst , but in small groups , or subclusters .
This may be an essential physical description for star formation in what will later be termed a ’ massive star cluster ’ .