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arXiv · 1101.3708

Shock-induced star cluster formation in colliding galaxies

Takayuki R. Saitoh·Hiroshi Daisaka·Eiichiro Kokubo·Junichiro Makino·Takashi Okamoto·Kohji Tomisaka·Keiichi Wada·Naoki Yoshida
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Abstract

We studied the formation process of star clusters using high-resolution N-body/smoothed particle hydrodynamcs simulations of colliding galaxies. The total number of particles is 1.2x10^8 for our high resolution run. The gravitational softening is 5 pc and we allow gas to cool down to \sim 10 K. During the first encounter of the collision, a giant filament consists of cold and dense gas found between the progenitors by shock compression. A vigorous starburst took place in the filament, resulting in the formation of star clusters. The mass of these star clusters ranges from 10^{5-8} Msun. These star clusters formed hierarchically: at first small star clusters formed, and then they merged via gravity, resulting in larger star clusters.

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Takayuki R. Saitoh, Hiroshi Daisaka, Eiichiro Kokubo, Junichiro Makino, Takashi Okamoto, Kohji Tomisaka, Keiichi Wada, Naoki Yoshida. 2011-01-19. Shock-induced star cluster formation in colliding galaxies. https://doi.org/10.1017/s1743921311000846

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