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The Frequency of Snowline-Region Planets from Four Years of OGLE-MOA-Wise Second-Generation MicrolensingWe present a statistical analysis of the first four seasons from a second-generation microlensing survey for extrasolar planets, consisting of near-continuous time coverage of 8 deg to the 2nd power of the Galactic bulge by the Optical Gravitational Lens Experiment (OGLE), Microlensing Observations in Astrophysics (MOA), and Wise microlensing surveys. During this period, 224 microlensing events were observed by all three groups. Over 12% of the events showed a deviation from single-lens microlensing, and for approx. 1/3 of those the anomaly is likely caused by a planetary companion. For each of the 224 events, we have performed numerical ray-tracing simulations to calculate the detection efficiency of possible companions as a function of companion-to-host mass ratio and separation. Accounting for the detection efficiency, we find that 55 +34 -22%of microlensed stars host a snowline planet. Moreover, we find that Neptune-mass planets are approx.10 times more common than Jupiter-mass planets. The companion-to-host mass-ratio distribution shows a deficit at q approx. 10 (exp -2), separating the distribution into two companion populations, analogous to the stellar-companion and planet populations, seen in radial-velocity surveys around solar-like stars. Our survey, however, which probes mainly lower mass stars, suggests a minimum in the distribution in the super-Jupiter mass range, and a relatively high occurrence of brown-dwarf companions.
Document ID
20170004636
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Shvartzvald, Y.
(Tel-Aviv Univ. Israel)
Maoz, D.
(Tel-Aviv Univ. Israel)
Udalski, A.
(Warsaw Univ. Warsaw, Poland)
Sumi, T.
(Osaka Univ. Osaka, Japan)
Friedmann, M.
(Tel-Aviv Univ. Israel)
Kaspi, S.
(Tel-Aviv Univ. Israel)
Poleski, R.
(Ohio State Univ. Columbus, OH, United States)
Szymanski, M. K.
(Warsaw Univ. Warsaw, Poland)
Skowron, J.
(Warsaw Univ. Warsaw, Poland)
Kozlowski, S.
(Warsaw Univ. Warsaw, Poland)
Wyrzykowski, L.
(Warsaw Univ. Warsaw, Poland)
Mroz, P.
(Warsaw Univ. Warsaw, Poland)
Pietrukowicz, P.
(Warsaw Univ. Warsaw, Poland)
Pietrzynski, G.
(Warsaw Univ. Warsaw, Poland)
Soszynski, I.
(Warsaw Univ. Warsaw, Poland)
Ulaczyk, K.
(Warwick Univ. Coventry, United Kingdom)
Abe, F.
(Nagoya Univ. Nagoya, Japan)
Barry, R. K.
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Bennett, D. P.
(Maryland Univ. Baltimore County Baltimore, MD, United States)
Bhattacharya, A.
(Notre Dame Univ. Notre Dame, IN, United States)
Bond, I. A.
(Massey University Auckland Auckland, New Zealand)
Freeman, M.
(Auckland Univ. New Zealand)
Inayama, K.
(Kyoto Sangyo Univ. Japan)
Itow, Y.
(Nagoya Univ. Nagoya, Japan)
Koshimoto, N.
(Osaka Univ. Osaka, Japan)
Date Acquired
May 18, 2017
Publication Date
February 27, 2016
Publication Information
Publication: Monthly Notices of the Royal Astronomical Society
Publisher: Oxford University Press
Volume: 457
Issue: 4
ISSN: 0035-8711
e-ISSN: 1365-8711
Subject Category
Astrophysics
Report/Patent Number
GSFC-E-DAA-TN42732
Funding Number(s)
CONTRACT_GRANT: NNG17PT01A
Distribution Limits
Public
Copyright
Other
Keywords
extrasolar planets

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