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Microlensing, flattening, $Ω_B$ and $h$: from assumptions, via data to tentative conclusions

Vesna Milosevic-Zdjelar·Srdjan Samurovic·Milan M. Cirkovic
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Abstract

Microlensing observations can be used for determining the shape of the Milky Way's halo. It can be shown that the data are best described with moderately flattened halo, 0.5 < q < 0.6. We discuss, by taking into account this result, the constraints on the baryonic mass-density parameter, $Ω_B$, and their implications on the value of the Hubble constant $H_0$, i.e. $h$. Our conclusion is that current data, in order to satisfy BBNS and Galaxy dynamics constraints, strongly suggest that $h$ should take values within the lower part of the permissible range, $h\sim 0.5$.

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Vesna Milosevic-Zdjelar, Srdjan Samurovic, Milan M. Cirkovic. 1999-09-14. Microlensing, flattening, $Ω_B$ and $h$: from assumptions, via data to tentative conclusions. https://arxiv.org/abs/astro-ph/9909240

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