The frequency of snowline-region planets from four-years of OGLE-MOA-Wise second-generation microlensing.

Autor: Shvartzvald Y; School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel.; The Wise Observatory Group., Maoz D; School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel.; The Wise Observatory Group., Udalski A; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Sumi T; Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Friedmann M; School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel.; The Wise Observatory Group., Kaspi S; School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel.; The Wise Observatory Group., Poleski R; Department of Astronomy, Ohio State University, 140 W. 18th Ave., Columbus, OH 43210, USA.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Szymański MK; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Skowron J; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Kozłowski S; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Wyrzykowski L; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Mróz P; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Pietrukowicz P; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Pietrzyński G; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Soszyński I; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Ulaczyk K; Department of Physics, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.; Optical Gravitational Lens Experiment (OGLE) Collaboration., Abe F; Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Barry RK; Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.; Microlensing Observations in Astrophysics (MOA) Collaboration., Bennett DP; University of Notre Dame, Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670, USA.; Microlensing Observations in Astrophysics (MOA) Collaboration., Bhattacharya A; University of Notre Dame, Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670, USA.; Microlensing Observations in Astrophysics (MOA) Collaboration., Bond IA; Institute of Information and Mathematical Sciences, Massey University, Private Bag 102-904, North Shore Mail Centre, Auckland, New Zealand.; Microlensing Observations in Astrophysics (MOA) Collaboration., Freeman M; Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand.; Microlensing Observations in Astrophysics (MOA) Collaboration., Inayama K; Department of Physics, Faculty of Science, Kyoto Sangyo University, 603-8555 Kyoto, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Itow Y; Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Koshimoto N; Department of Earth and Space Science, Osaka University, Osaka 560-0043, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Ling CH; Institute of Information and Mathematical Sciences, Massey University, Private Bag 102-904, North Shore Mail Centre, Auckland, New Zealand.; Microlensing Observations in Astrophysics (MOA) Collaboration., Masuda K; Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Fukui A; Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, Asakuchi, Okayama 719-0232, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Matsubara Y; Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Muraki Y; Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Ohnishi K; Nagano National College of Technology, Nagano 381-8550, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Rattenbury NJ; Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001, New Zealand.; Microlensing Observations in Astrophysics (MOA) Collaboration., Saito T; Tokyo Metropolitan College of Aeronautics, Tokyo 116-8523, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Sullivan DJ; School of Chemical and Physical Sciences, Victoria University, Wellington, New Zealand.; Microlensing Observations in Astrophysics (MOA) Collaboration., Suzuki D; University of Notre Dame, Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670, USA.; Microlensing Observations in Astrophysics (MOA) Collaboration., Tristram PJ; Mt. John University Observatory, P.O. Box 56, Lake Tekapo 8770, New Zealand.; Microlensing Observations in Astrophysics (MOA) Collaboration., Wakiyama Y; Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration., Yonehara A; Department of Physics, Faculty of Science, Kyoto Sangyo University, 603-8555 Kyoto, Japan.; Microlensing Observations in Astrophysics (MOA) Collaboration.
Jazyk: angličtina
Zdroj: Monthly notices of the Royal Astronomical Society [Mon Not R Astron Soc] 2016 Apr 21; Vol. 457 (4), pp. 4089-4113. Date of Electronic Publication: 2016 Feb 27.
DOI: 10.1093/mnras/stw191
Abstrakt: We 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 2 of the Galactic bulge by the OGLE, 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 ~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 - 22 + 34 % of microlensed stars host a snowline planet. Moreover, we find that Neptunes-mass planets are ~ 10 times more common than Jupiter-mass planets. The companion-to-host mass ratio distribution shows a deficit at q ~ 10 -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.
Databáze: MEDLINE