# Direct collapse black hole formation via high-velocity collisions of protogalaxies

@article{Inayoshi2015DirectCB,
title={Direct collapse black hole formation via high-velocity collisions of protogalaxies},
author={Kohei Inayoshi and Eli Visbal and Kazumi Kashiyama},
journal={Monthly Notices of the Royal Astronomical Society},
year={2015},
volume={453},
pages={1692-1700}
}
• Published 2 April 2015
• Physics
• Monthly Notices of the Royal Astronomical Society
We propose high-velocity collisions of protogalaxies as a new pathway to form supermassive stars (SMSs) with masses of ∼ 10 5 M⊙ at high redshift (z > 10). When protogalaxies hosted by dark matter halos with a virial temperature of ∼ 10 4 K collide with a relative velocity & 200 km s −1 , the gas is shock-heated to ∼ 10 6 K and subsequently cools isobarically via free-free emission and He + , He, and H line emission. Since the gas density (& 10 4 cm −3 ) is high enough to destroy H2 molecules…
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