ALMA Reveals Potential Localized Dust Enrichment from Massive Star Clusters in II Zw 40
Abstract
We present subarcsecond images of submillimeter CO and continuum emission from a local galaxy forming massive star clusters: the blue compact dwarf galaxy II Zw 40. At ∼0.″4 resolution (20 pc), the CO(3-2), CO(1-0), 3 mm, and 870 μm continuum maps illustrate star formation on the scales of individual molecular clouds. Dust contributes about one-third of the 870 μm continuum emission, with free-free accounting for the rest. On these scales, there is not a good correspondence between gas, dust, and free-free emission. Dust continuum is enhanced toward the star-forming region as compared to the CO emission. We suggest that an unexpectedly low and spatially variable gas-to-dust ratio is the result of rapid and localized dust enrichment of clouds by the massive clusters of the starburst.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 2016
- DOI:
- 10.3847/2041-8205/833/1/L6
- arXiv:
- arXiv:1611.09936
- Bibcode:
- 2016ApJ...833L...6C
- Keywords:
-
- galaxies: dwarf;
- galaxies: individual: IIZw40;
- galaxies: star clusters: general;
- galaxies: starburst;
- submillimeter: galaxies;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 5 pages, 3 figures