SIMBAD references

We obtained 350 and 850 µm continuum maps of the infrared dark cloud G049.40-00.01. Twenty-one dense clumps were identified within G049.40-00.01 based on the 350 µm continuum map with an angular resolution of about 9".6. We present submillimeter continuum maps and report physical properties of the clumps. The masses of clumps range from 50 to 600 M_☉. About 70% of the clumps are associated with bright 24 µm emission sources, and they may contain protostars. The two most massive clumps show extended, enhanced 4.5 µm emission indicating vigorous star-forming activity. The clump-size-mass distribution suggests that many of them are forming high-mass stars. G049.40-00.01 contains numerous objects in various evolutionary stages of star formation, from pre-protostellar clumps to H II regions.