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arXiv · astro-ph/0408125

Radial truncations in stellar discs in galaxies

M. Kregel·P. C. van der Kruit
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Abstract

We discuss the possible origin of the radial truncations in stellar discs, using measurements that we presented in an earlier paper (Kregel, van der Kruit & de Grijs, 2002). A tentative correlation is found with the de-projected face-on central surface brightness; lower surface brightness discs tend to have a smaller truncation radius in units of scalelength. This and our earlier finding that in smaller spirals the truncation tends to occur at a larger number of scalelengths are best reproduced when the truncation is caused by a constant gas density threshhold on star formation.

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M. Kregel, P. C. van der Kruit. 2004-08-06. Radial truncations in stellar discs in galaxies. https://doi.org/10.1111/j.1365-2966.2004.08307.x

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