COMPACT HII-REGIONS IN THE LARGE-MAGELLANIC-CLOUD OBSERVED BY ISO

We present ISOCAM observations of five fields in the Large Magellanic Cloud centered on IRAS point sources with colors of ultracompact HII r egions. Three bright sources of parsec or subparsec size, with luminos ities consistent with being embedded O stars, are detected at 15 mu m in two fields belonging to the HII region N 159. Using published high resolution radio observations, it is found that two of these sources m ay be ultracompact HII regions with a turnover frequency above 2.4 GHz , while the other is identified with a known compact HII region. If th eir nature as true ultracompact HII regions is confirmed by follow-up observations, these objects can provide a first sample useful for futu re studies of early massive star evolution in a low metallicity enviro nment.