Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-28T20:40:08.507Z Has data issue: false hasContentIssue false

Microlensing Constraints on Low-Mass Companions

Published online by Cambridge University Press:  26 May 2016

B. Scott Gaudi*
Affiliation:
Hubble Fellow, School of Natural Sciences, Institute for Advanced Study, Einstein Drive, Princeton, NJ, 08540

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Microlensing is sensitive to binary, brown dwarf (BD), and planetary companions to normal stars in the Galactic bulge with separations between about 1–10 AU. The accurate, densely-sampled photometry of microlensing events needed to detect planetary companions has been achieved by several follow-up collaborations. Detailed analysis of microlensing events toward the bulge demonstrates that less than 45% of M-dwarfs in the bulge have MJup companions between 1 and 5 AU. Detection of binary and BD companions using microlensing is considerably easier; however, the interpretation is hampered by their non-perturbative influence on the parent lightcurve. I demonstrate that ~ 25% of BD companions with separations 1 – 10AU should be detectable with survey-quality data (~ 1 day sampling and ~ 5% photometry). Survey data is more amenable to generic, brute-force analysis methods and less prone to selection biases. An analysis of the ~ 1500 microlensing events detected by OGLE-III in the next three years should test whether the BD desert exists at separations 1 – 10AU from M-dwarfs in the Galactic bulge.

Type
Part 6. Searches for Substellar Companions
Copyright
Copyright © Astronomical Society of the Pacific 2001 

References

Albrow, M. D. et al. 2001, ApJ, 556, L113 CrossRefGoogle Scholar
Bond, I. A. et al. 2002, MNRAS, 333, 71 Google Scholar
Gaudi, B. S. et al. 2002, ApJ, 566, 463 CrossRefGoogle Scholar
Gizis, J.E., Kirkpatrick, J.D., Burgasser, A., Reid, I.N., Monet, D.G., Liebert, J., Wilson, J.C. 2001, ApJ, 551, L163 Google Scholar
Jaroszyński, M. 2002, Acta Astron., accepted (astro-ph/0203476) Google Scholar
Lowrance, P.J. 2001, Ph.D. Thesis, UCLA Google Scholar
Mao, S., & Paczyński, B. 1991, ApJ, 374, 37 Google Scholar
Marcy, G. W. & Butler, R. P. 2000, PASP, 112, 137 CrossRefGoogle Scholar
McCarthy, C. 2001, Ph.D. Thesis, UCLA Google Scholar
Oppenheimer, B. R., Golimowski, D. A., Kulkarni, S. R., Matthews, K., Nakajima, T., Creech-Eakman, M., & Durrance, S. T. 2001, AJ, 121, 2189 Google Scholar
Rhie, S. H. et al. 2000, ApJ, 533, 378 CrossRefGoogle Scholar
Tsapras, Y. et al. 2001, MNRAS, 325, 1205 Google Scholar
Udalski, A. et al. 2002, Acta Astronomica, 52, 1 Google Scholar
Zucker, S. & Mazeh, T. 2002, ApJ, 568, L113 Google Scholar