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arXiv · astro-ph/9711263

The Spheroid Luminosity and Mass Functions From HST Star Counts

Andrew Gould·Chris Flynn·John N. Bahcall
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Abstract

We analyze 166 spheroid subdwarfs $(6.5 M >0.09 Msun. The spheroid therefore does not contribute significantly to microlensing unless the mass function changes slope dramatically in the substellar range. The total local mass density of spheroid stars (including remnants and unseen binary companions) is ρ~ 6.4E-5 Msun/pc^3, with an uncertainty of about 50%. The power-law indices α=0.25 for the spheroid and α=0.44 for the disk (both uncorrected for binaries) are similar to those of globular clusters of moderate to high metallicity.

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Andrew Gould, Chris Flynn, John N. Bahcall. 1998-03-03. The Spheroid Luminosity and Mass Functions From HST Star Counts. https://doi.org/10.1086/306023

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