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arXiv · astro-ph/9612133

The Chemical Residue of a White Dwarf-Dominated Galactic Halo

Brad K. Gibson·Jeremy R. Mould
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Abstract

Halo initial mass functions (IMFs), heavily-biased toward white dwarf (WD) precursors (i.e. 1->8 M_sun), have been suggested as a suitable mechanism for explaining microlensing statistics along the line of sight to the LMC. Such IMFs can apparently be invoked without violating the observed present-day WD luminosity function. By employing a simple chemical evolution argument, we demonstrate that reconciling the observed halo Population II dwarf abundances (i.e. [C,N/O]=-0.5), with that expected from the postulated ``WD-heavy'' IMF (i.e. [C,N/O]=+0.5), is difficult.

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Brad K. Gibson, Jeremy R. Mould. 1996-12-13. The Chemical Residue of a White Dwarf-Dominated Galactic Halo. https://doi.org/10.1086/304140

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