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تسجيل مستخدم جديدSmoke in the Smoke Rings: ISO Observations of Dust in Collisional Ring Galaxies
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P. N. Appleton
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Collisional ring galaxies probably result from a head-on collision between a compact companion galaxy and a gas-rich disk system. We present a review of the discovery of warm dust in five collisional rings observed by ISO which range in total Far-IR luminosity from 10$^{10}$~ $<$ ~L$_{FIR}$ ~$<$ ~10$^{11}$ L$odot$. The results show that in most cases, the mid-IR (MIR) flux is often a significant fraction of the total energy budget of star formation activity in these galaxies (at least 10% even in the least powerful cases). We argue that the MIR emission, when combined with optical and radio observations, allows us to build a more complete picture of activity in these collisional systems. Although not as extreme as ULIRGs, these collisional systems provide low-redshift examples of the early effects of galaxy collisions on the ISM and may be relevant to the collisional assembly of galaxy disk components at high redshift.
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We present the first mid-infrared (Mid-IR) ($lambda5-15mu$m) and radio continuum ($lambdalambda$20,~6 and 3.6 cm) observations of the star-forming collisional ring galaxy VII Zw 466 and its host group made with the Infrared Space Observatory and the
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