Unbound or distant planetary mass population detected by gravitational microlensing

@article{SumiKamiyaBennettBondAbeBotzlerFukuiFurusaw20,
  title={Unbound or distant planetary mass population detected by gravitational microlensing},
  author={T. K. D. P. I. A. F. C. S. A. K. J. B. Y. P. M. A. W. Sumi Kamiya Bennett Bond Abe Botzler Fukui Furusaw and Takahiro Sumi and Koki Kamiya and David P. Bennett and Ian A. Bond and Fumio Abe and Christine S. Botzler and Akihiko Fukui and Kei Furusawa and John B. Hearnshaw and Yoshitaka Itow and Pam M. Kilmartin and Aarno Korpela and W. Lin and Cho Hong Ling and Kimiaki Masuda and Yutaka Matsubara and N. Miyake and Masanori Motomura and Yasushi Muraki and M. Nagaya and S. Nakamura and Kouji Ohnishi and Teppei Okumura and Yvette C Perrott and Nicholas J. Rattenbury and To. Saito and T. Sako and Denis J. Sullivan and Winston L. Sweatman and Paul J. Tristram and Ph. Yock and A. M. K. M. G. R. I. Ł. K. Udalski Szymański Kubiak Pietrzyński Poleski Soszy and Andrzej Udalski and Michał K. Szymański and Marcin Kubiak and Grzegorz Pietrzyński and Radek Poleski and Igor Soszyński and Łukasz Wyrzykowski and Krzysztof Ulaczyk},
  journal={Nature},
  year={2011},
  volume={473},
  pages={349-352}
}
  • T. K. D. P. I. A. F. C. S. A. K. J. B. Y. P. M. A. W. Sumi Kamiya Bennett Bond Abe Botzler Fukui Furusaw, T. Sumi, K. Ulaczyk
  • Published 1 May 2011
  • Physics, Geology
  • Nature
Since 1995, more than 500 exoplanets have been detected using different techniques, of which 12 were detected with gravitational microlensing. Most of these are gravitationally bound to their host stars. There is some evidence of free-floating planetary-mass objects in young star-forming regions, but these objects are limited to massive objects of 3 to 15 Jupiter masses with large uncertainties in photometric mass estimates and their abundance. Here, we report the discovery of a population of… 

No large population of unbound or wide-orbit Jupiter-mass planets

TLDR
A sample of microlensing events six times larger than that of ref. 11 is analysed, finding no excess of events with timescales in this range, with a 95 per cent upper limit on the frequency of Jupiter-mass free-floating or wide-orbit planets of 0.25 planets per main-sequence star.

Microlensing Constraints on the Abundance of Extrasolar Planets

  • A. Cassan
  • Physics, Geology
    Proceedings of the International Astronomical Union
  • 2012
Abstract Galactic gravitational microlensing is a powerful technique to detect extrasolar planets at large orbital distances from their stars, from giant down to Earth-mass planets. We report a

One or more bound planets per Milky Way star from microlensing observations

TLDR
It is concluded that stars are orbited by planets as a rule, rather than the exception, and that of stars host Jupiter-mass planets 0.5–10 au (Sun–Earth distance) from their stars.

Direct imaging constraints on planet populations detected by microlensing

Results from gravitational microlensing suggested the existence of a large population of free-floating planetary mass objects. The main conclusion from this work was partly based on constraints from

Astrophysical applications of gravitational microlensing

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Two new free-floating or wide-orbit planets from microlensing

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CONSTRAINING THE FREQUENCY OF FREE-FLOATING PLANETS FROM A SYNTHESIS OF MICROLENSING, RADIAL VELOCITY, AND DIRECT IMAGING SURVEY RESULTS

A microlensing survey by Sumi et al. exhibits an overabundance of short-timescale events (STEs; tE < 2 days) relative to what is expected from known stellar populations and a smooth power-law

A Terrestrial-mass Rogue Planet Candidate Detected in the Shortest-timescale Microlensing Event

Some low-mass planets are expected to be ejected from their parent planetary systems during early stages of planetary system formation. According to planet formation theories, such as the core

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Current microlensing surveys are sensitive to free-floating planets down to Earth-mass objects. All published microlensing events attributed to unbound planets were identified based on their short

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Unlike most other planet-detection techniques, gravitational microlensing does not rely on detection of photons from either the host or the planet. Rather, planets are discovered by their
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