Dust in the Small Magellanic Cloud

Details Dust in the Small Magellanic Cloud Dust in the Small Magellanic Cloud

Dec 2004

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004sf2a.conf..447b&link_type=abstract

SF2A-2004: Semaine de l'Astrophysique Francaise, meeting held in Paris, France, June 14-18, 2004. Edited by F. Combes, D. Barret

Astronomy and Astrophysics

Astrophysics

Scientific paper

The Small Magellanic Cloud is a nearby galaxy of low metallicity, strong star formation rate in spite of an apparently small proportion of molecular gas (weak and rare CO detections). The observations of gas and dust of this galaxy allow to study the impact of metallicity and of star formation history on dust abundance. The multi-wavelength dust emission, outside of the star formation areas, allows to measure the temperature and the emissivity by hydrogen atom of the grains in the diffuse medium of the SMC. The emissivity of the grains in the diffuse medium is 30 times weaker than in the solar vicinity, whereas the difference in metallicity is only 10. The gas-to-dust ratio is thus 3 times higher in the diffuse medium of the SMC than in the solar vicinity. There is thus a smaller fraction of metals in solid form in the SMC. The study of a quiescent molecular cloud, SMC B1#1, shows the opposite result. The modeling of emission of dust in this cloud requires high abundance of dust. For a column density of hydrogen traced by CO integrated emission, one finds a gas-to-dust extinction ratio of galactic value, incompatible with measurements of metallicity in the SMC. There is thus a large quantity of hydrogen not traced by CO emission. Moreover, the gas-to-dust ratio in the dense medium of the SMC is definitely weaker than in the diffuse medium. This evolution of the gas-to-dust ratio from diffuse medium to dense medium can be reproduced by a frequent destruction of the grains by the explosions of supernovae in the diffuse medium and accretion on dust of the heavy elements in the molecular clouds where the grains are protected.

Affiliated with

Also associated with

No associations

Rating

Dust in the Small Magellanic Cloud does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Dust in the Small Magellanic Cloud, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dust in the Small Magellanic Cloud will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1166191