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arXiv · 1812.06144

New perspectives on galactic angular momentum, galaxy formation, and the Hubble Sequence

S. Michael Fall·Aaron J. Romanowsky
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Abstract

This paper provides a summary of our recent work on the scaling relations between the specific angular momentum j_* and mass M_* of the stellar parts of normal galaxies of different bulge fraction beta_*. We find that the observations are consistent with a simple model based on a linear superposition of disks and bulges that follow separate scaling relations of the form j_*d ~ M_*d^alpha and j_*b ~ M_*b^alpha with alpha = 0.67 +/- 0.07 but offset from each other by a factor of 8 +/- 2 over the mass range 8.9 <= log (M_*/M_Sun) <= 11.8. This model correctly predicts that galaxies follow a curved 2D surface in the 3D space of log j_*, log M_*, and beta_*.

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S. Michael Fall, Aaron J. Romanowsky. 2018-12-14. New perspectives on galactic angular momentum, galaxy formation, and the Hubble Sequence. https://doi.org/10.5281/zenodo.1481577

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