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تسجيل مستخدم جديدLarge-Scale Outer Rings of Early-type Disk Galaxies
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Irina P. Kostiuk
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We have searched for presence of current star formation in outer stellar rings of early-type disk (S0-Sb) galaxies by inspecting a representative sample of nearby galaxies with rings from the recent Spitzer catalog ARRAKIS (Comeron et al. 2014). We have found that regular rings (of R-type) reveal young stellar population with the age of less than 200~Myr in about half of all the cases, while in the pseudorings (open rings, R), which inhabit only spiral galaxies, current star formation proceeds almost always.
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