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arXiv · astro-ph/9808344

Starburst in the Intragroup Medium of Stephan's Quintet

Cong Xu·Richard Tuffs
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Abstract

Based on new ISO mid-infrared observations and ground based $H_α$ and near-infrared observations, we report the detection of a bright starburst in the intragroup medium (IGM) of the famous compact group of galaxies Stephan's Quintet (Source A in Fig.1). We demonstrate that this starburst is caused by a collision between a high velocity ($δ$V$\sim$ 1000 km/sec) intruder galaxy (NGC7318b) and the IGM of the group. While this is the only starburst known today that is induced by a galaxy/cold-intergalactic-medium collision, it provides new constraints to the theory for interaction-induced starbursts, and may hint at a new mechanism for the star formation excess seen in more distant clusters.

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Cong Xu, Richard Tuffs. 1998-08-31. Starburst in the Intragroup Medium of Stephan's Quintet. https://doi.org/10.1086/306771

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