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arXiv · astro-ph/9904362

Quasar-microlensing versus star-microlensing evidence of small-planetary-mass objects as the dominant inner-halo galactic dark matter

Abstract

We examine recent results of two kinds of microlensing experiments intended to detect galactic dark matter objects, and we suggest that the lack of short period star-microlensing events observed for stars near the Galaxy does not preclude either the ``rogue planets'' identified from quasar-microlensing by Schild 1996 as the missing-mass of a lens galaxy, or the clumps of such objects predicted by the new Gibson 1996-2000 hydro-gravitational theory as the inner-halo galactic dark matter. We point out that such micro-brown-dwarfs in nonlinear accretional cascades to form stars give intermittent lognormal number density n_p distributions. Hence, star-microlensing searches that focus on a small fraction of the sky and assume a uniform distribution for n_p are subject to undersampling errors. Sparse independent samples give modes smaller than means of the highly skewed lognormal distributions expected. Quasar-microlensing searches with higher optical depths are less affected by intermittency. We attempt to reconcile the results of the star-microlensing and quasar-microlensing studies. We conclude that star microlensing searches cannot exclude and are unlikely to even detect these objects so easily observed by quasar-microlensing and so robustly predicted by the new theory.

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BibTeXRIS

Carl H. Gibson, Rudolph E. Schild. 2000-04-26. Quasar-microlensing versus star-microlensing evidence of small-planetary-mass objects as the dominant inner-halo galactic dark matter. https://arxiv.org/abs/astro-ph/9904362

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