MOA-II microlensing exoplanet survey 0.25 Takahiro Sumi (Nagoya univ.) the MOA collaboration

planetary microlensing 0.5

Sensitivity of various methods RV　 transit Direct image Microlensing： not rely on flux from host 1.25 small planet：　down to Earth 1-6 AU ： around snow line Faint star :M-dwarf, brown dwarf No host ：　free floating planet Far system:　galactic distribution Credit Bennett

Sensitivity of microlensing 1

Microlensing observation global network Survey Group Follow-up Group Micro lensing Alert  MOA(NewZealand) OGLE(Chile), (no observation in 2009) Wide field Low cadence PLANET FUN Pointing each candidate High cadence Anomaly Alert  1

MOA (since 1995) （Microlensing Observation in Astrophysics） （ New Zealand/Mt. John Observatory, Latitude： 44S, Alt: 1029m ） Mirror : 1.8m CCD : 80M pix. FOV : 2.2 deg.2 3/4

MOA (until ~1500) （the world largest bird in NZ） height:3.5ｍ weight:240kg can not fly Extinct 500 years ago （Maori ate them) 0.5

Observation by MOA 50 deg.2(20Mstars) 1obs./night.(>MJup) 1obs./95min.(Mjup) 1obs./47min. (Mnep) 1obs./15min. (M) G.C. 3/4 489events(3planets) (16/9/2009) http://www.massey.ac.nz/~iabond/alert/alert.html

Real-time Anomaly check at Mt.John The planet found on 11/9/2009 3/4 anomaly

The first planet via microlensing OGLE 2003-BLG-235/MOA 2003-BLG-53 Mass： ~3MJ, Sep. : ~4AU 1/4

2nd Exoplanet Discovery by lensing :OGLE 2005-BLG-71 (Udalski, et. al.2006 Dong et al. 2008) ML=0.46±0.04 DL=3.3±0.4kpc Mp=3.5±0.3MJ Sep=3.6±0.2AU V~103km/s (HST) Data from OGLE, FUN, PLANET & MOA The most massive Planet at wide sep for M-dwarf Challenging to form in core-accretion model 0.5 Thick disk

5.5 Earth mass:OGLE-2005-BLG-390 Sep~3AU Proved microlensing is sensitive to Super earth 0.5 The smallest Planet！(at that time) (Beaulieu et al. 2006, Nature,439,437)

Jupiter/Saturn analog : OGLE-2006-BLG-109L Host mass ２５multiple system Habitable zone snow line giant planets are supposed to form outside of snow line, but not observed First case that both giant planets are outside of snow line 1.25 OGLE-2006-BLG-109L Jupiter, Saturn

The smallest host star：MOA 2007-BLG-192 Bennett et al. 2008 With planet No planet Mhost=0.06 (0.024-0.128) M Mp =3.3 (1.0-17.8)MEarth MOA OGLE VLT-NACO(AO) image Lens is faint: Late M-dwarf or brown dwarf Can be determined by HST 5 years later 1 No flux from Lens

Summary of Planet candidates Gould et al. 2006: “Cool Neptune” are common in K,M-dwarf： ~40% (>16% at 90% confidence.)” consistent with formation theory. (Ida & Lin, 2004) 1 preliminary. Credit Bennett

Galactic distribution Host mass Uniform in DL >60% of lensing events are due to bulge lens Sun GC Distance Density distribution 1 Few Planets in GB!? (be careful: there may be Observational bias)

Free floating planet half planets rejected after 108yr Free floating Planet scattering Simulation by Veras et al. 2009 half planets rejected after 108yr Free floating Microlensing can find tE=1.2days ~1MJ 0.5

summary 9 exoplanets (8system) via microlensing published 3 exoplanets in preparation. MOA is the only survey group in 2009 (489events so far) 3(+2) exoplanets candidates in 2009 so far. Unique planets: The largest Giant planet at wide sep. around M-dwarf in Thick disk Jupiter/Saturn analog Exoplanet around Brown dwarf ”Cool Neptune“ are common in K,M-dwarf Evidence of few exoplanets in the bulge?? Free floating planets Earth Mass planet soon! 075

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OGLE-2007-BLG-368 (MOA-2007-BLG-308) q=1x10^-4, sep= 0.9RE Keck, AO, K-band OGLE, I-band

Planetary microlensing D(kpc) ML(M) Mp Sep (AU) OGLE-2003-BLG-235/MOA-2003-BLG-53 θE,Bayesian,flux limit OGLE-2005-BLG-169 OGLE-2005-BLG-071 θE,Parallax,Astrometry.Thick disk. Most Massive planet in M-dwarf OGLE-2005-BLG-390 θE,Bayesian OGLE-2006-BLG-109 θE, Parallax MOA-2007-BLG-192 θE,Parallax.VLT,Smallest host MOA-2007-BLG-400 OGLE-2007-BLG-368 In preparation OGLE-2007-BLG-349 MOA-2007-BLG-197 MOA-2008-BLG-310 If blend is lens