Limits on the Abundance of Galactic Planets From Five Years of Planet Observations

M. D. Albrow; J. An; J. -P. Beaulieu; J. A. R. Caldwell; D. L. DePoy; M. Dominik; B. S. Gaudi; A. Gould; J. Greenhill; K. Hill; S. Kane; R. Martin; J. Menzies; R. M. Naber; J. -W. Pel; R. W. Pogge; K. R. Pollard; P. D. Sackett; K. C. Sahu; P. Vermaak; P. M. Vreeswijk; R. Watson; A. Williams; The PLANET Collaboration

doi:10.1086/323141

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Limits on the Abundance of Galactic Planets From Five Years of Planet Observations

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Abstract

We search for signatures of planets in 43 intensively monitored microlensing events that were observed between 1995 and 1999. Planets would be expected to cause a short duration (~1 day) deviation on the smooth, symmetric light curve produced by a single-lens. We find no such anomalies and infer that less than 1/3 of the ~0.3 M_sun stars that typically comprise the lens population have Jupiter-mass companions with semi-major axes in the range of 1.5 AU <a < 4 AU. Since orbital periods of planets at these radii are 3-15 years, the outer portion of this region is currently difficult to probe with any other technique.

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M. D. Albrow, J. An, J. -P. Beaulieu, J. A. R. Caldwell, D. L. DePoy, M. Dominik, B. S. Gaudi, A. Gould, J. Greenhill, K. Hill, S. Kane, R. Martin, J. Menzies, R. M. Naber, J. -W. Pel, R. W. Pogge, K. R. Pollard, P. D. Sackett, K. C. Sahu, P. Vermaak, P. M. Vreeswijk, R. Watson, A. Williams, The PLANET Collaboration. 2001-07-17. Limits on the Abundance of Galactic Planets From Five Years of Planet Observations. https://doi.org/10.1086/323141

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