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MACHO COLLABORATION SEARCH FOR BARYONIC DARK MATTER VIA GRAVITATIONAL MICROLENSING

K. Griest·C. Alcock·R. A. Allsman·T. S. Axelrod·D. P. Bennett·K. H. Cook·K. C. Freeman·J. Guern·M. Lehner·S. L. Marshall·S. Perlmutter·B. A. Peterson·M. R. Pratt·P. J. Quinn·A. W. Rodgers·C. W. Stubbs·W. Sutherland·D. Welch
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Abstract

Results are presented from the MACHO collaboration gravitational microlensing search. The experiment and the nearly 50 microlensing events that have been detected are described. Limits on the baryonic content of the halo are given, as are estimates of the Macho contribution to the dark halo. Optical depths toward the bulge, and several unusual events such as a binary lens and a parallax event are discussed. Possible interpretations of these results are also discussed.

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K. Griest, C. Alcock, R. A. Allsman, T. S. Axelrod, D. P. Bennett, K. H. Cook, K. C. Freeman, J. Guern, M. Lehner, S. L. Marshall, S. Perlmutter, B. A. Peterson, M. R. Pratt, P. J. Quinn, A. W. Rodgers, C. W. Stubbs, W. Sutherland, D. Welch. 1995-06-02. MACHO COLLABORATION SEARCH FOR BARYONIC DARK MATTER VIA GRAVITATIONAL MICROLENSING. https://arxiv.org/abs/astro-ph/9506016

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