MOA-II Microlensing SurveyMOA-II Microlensing Survey

Takahiro Sumi (Nagoya University)

the MOA collaborationAbe,F; Bennett,P.D;Bond, I. A.;Fukui,A;Furusawa,K; Hearnshaw, J. B.;Itow,Y;

Kilmartin, P. M.; Koki, K; Masuda, K.; Matsubara, Y.;Miyake,N; Muraki, Y.; Nagaya,M;Okumura,M; Ohnishi,K;Rattenbury, N. J.; Saitou,T;Sako, T.;

Sullivan, D. J.;Sumi, T.;Tristram,P.; Wood, J. N.; Yock, P. C. M.

Takahiro Sumi (Nagoya University)

the MOA collaborationAbe,F; Bennett,P.D;Bond, I. A.;Fukui,A;Furusawa,K; Hearnshaw, J. B.;Itow,Y;

Kilmartin, P. M.; Koki, K; Masuda, K.; Matsubara, Y.;Miyake,N; Muraki, Y.; Nagaya,M;Okumura,M; Ohnishi,K;Rattenbury, N. J.; Saitou,T;Sako, T.;

Sullivan, D. J.;Sumi, T.;Tristram,P.; Wood, J. N.; Yock, P. C. M.

MOA (since 1995)

（ Microlensing Observation in Astrophysics ）（ New Zealand/Mt. John Observatory, Latitude ： 44S, Alt: 1029m ）

MOA (since 1995)

（ Microlensing Observation in Astrophysics ）（ New Zealand/Mt. John Observatory, Latitude ： 44S, Alt: 1029m ）

1995~1998:MOA-0: 0.6m, 9Mpix

1999~2005:MOA-I : 0.6m, 24Mpix

2005~ :MOA-II: 1.8m, 80Mpix

1995~1998:MOA-0: 0.6m, 9Mpix

1999~2005:MOA-I : 0.6m, 24Mpix

2005~ :MOA-II: 1.8m, 80Mpix

MOA (until ~1500)

（ The world largest bird which was in NZ ）

MOA (until ~1500)

（ The world largest bird which was in NZ ）

• height:3.5 ｍ• weight:240kg• can not fly• extinct 5 ００ years

ago

（ Maori ate them)

witnesses until ~1850.

Remind me …

• height:3.5 ｍ• weight:240kg• can not fly• extinct 5 ００ years

ago

（ Maori ate them)

witnesses until ~1850.

Remind me … Nessie

MOA’s scientific goalsMOA’s scientific goals

1,Galactic Dark Matter (towards the LMC & SMC)

Halo MACHOs or self-lensing?

1,Galactic Dark Matter (towards the LMC & SMC)

Halo MACHOs or self-lensing?

Halo Dark Matter?or

Self-lensing?

Halo Dark Matter?or

Self-lensing?

Tisserand et al.2006

MACHO 5.7 yrs & EROS 5yrs

MOA’s scientific goalsMOA’s scientific goals

1,Galactic Dark Matter (towards the LMC & SMC) Halo MACHOs or self-lensing?

2,The Galactic structure (towards the Bulge) Optical depth

time scale,tE

Red Clump Giants

1,Galactic Dark Matter (towards the LMC & SMC) Halo MACHOs or self-lensing?

2,The Galactic structure (towards the Bulge) Optical depth

time scale,tE

Red Clump Giants

the Galactic Bar structure the Galactic Bar structure (face on, from North)

8kpc

G.C.Obs.

1, Microlensing Optical depth, (Alcock et al. 2000; Afonso et al.2003; Sumi et al. 2003;Popowski et al. 2004; Hamadache et al. 2006;Sumi et al. 2006)

Event Timescale, tE=RE/vt, (Evans & Belokurov,2002, Wood & Mao 2005)

M=1.61010M, axis ratio (1:0.3:0.2), ~20

1, Microlensing Optical depth, (Alcock et al. 2000; Afonso et al.2003; Sumi et al. 2003;Popowski et al. 2004; Hamadache et al. 2006;Sumi et al. 2006)

Event Timescale, tE=RE/vt, (Evans & Belokurov,2002, Wood & Mao 2005)

M=1.61010M, axis ratio (1:0.3:0.2), ~20

2, Brightness of Red Clump Giant (RCG)and RRLyrae stars, (Stanek et al. 1997, Sumi 2004; Collinge, Sumi & Fabrycky, 2006)

2, Brightness of Red Clump Giant (RCG)and RRLyrae stars, (Stanek et al. 1997, Sumi 2004; Collinge, Sumi & Fabrycky, 2006)

3, Proper motions of RCG,(Sumi, Eyer & Wozniak, 2003; Sumi et al. 2004;Rattenbury et al.2007), Proper motion of 5M stars, I<18 mag, ~1mas/yr3, Proper motions of RCG,(Sumi, Eyer & Wozniak, 2003; Sumi et al. 2004;Rattenbury et al.2007), Proper motion of 5M stars, I<18 mag, ~1mas/yr

MOA’s scientific goalsMOA’s scientific goals

1,Galactic Dark Matter (towards the LMC & SMC) Halo MACHOs or self-lensing?

2,The Galactic structure (towards the Bulge) Optical depth

time scale,tE

Red Clump Giants

3,Exoplanets (towards the Bulge) Microlensing & transit

1,Galactic Dark Matter (towards the LMC & SMC) Halo MACHOs or self-lensing?

2,The Galactic structure (towards the Bulge) Optical depth

time scale,tE

Red Clump Giants

3,Exoplanets (towards the Bulge) Microlensing & transit

Theoretical v.s. ObservationTheoretical v.s. Observation

red ： Gass Giants青： Ice planets緑： Rocky planets

Ida & Lin, 2004

100m/s

10m/s

1m/s

Simulation Observation

Observational targetsObservational targets

LMCLMC

50kpc50kpc

　　　　 event rate:event rate:

LMC,SMC : LMC,SMC : ~2~2 events/yr (events/yr (~10~10-7-7 ))

Bulge : Bulge : ~500~500events/yr (events/yr (~10~10-6-6 ))

　　　　 Planetary event : Planetary event : ~10~10-2-2

　　　　 event rate:event rate:

LMC,SMC : LMC,SMC : ~2~2 events/yr (events/yr (~10~10-7-7 ))

Bulge : Bulge : ~500~500events/yr (events/yr (~10~10-6-6 ))

　　　　 Planetary event : Planetary event : ~10~10-2-2

7.5kpc, GC7.5kpc, GC7.5kpc, GC7.5kpc, GC

PLANETPLANET

FUNFUN

• Pointing each candidatePointing each candidate• High cadenceHigh cadence• Strategy based on Strategy based on

published photometrypublished photometry to catch short deviation.to catch short deviation.

MOAMOA(NewZealand)(NewZealand)

OGLEOGLE(Chile)(Chile)

• Wide field Wide field • Low cadenceLow cadence• Continuous surveyContinuous survey

Microlensing observation networkMicrolensing observation network

Survey GroupSurvey Group Follow-up GroupFollow-up GroupMicroMicrolensinglensingAlertAlert

AnomalyAnomaly AlertAlert

Anyone who wants alert is welcome to sign up Anyone who wants alert is welcome to sign up on the websites.on the websites.

Paczyński’s LegacyPaczyński’s Legacy

• The planet discovery via microlensing by collaboration of these groups are Paczyński’s Legacy

• Idea of the method.• Idea of putting data on public and sharing photometry

with other groups. useful to decide strategy to catch rare short planetary deviation.

• The planet discovery via microlensing by collaboration of these groups are Paczyński’s Legacy

• Idea of the method.• Idea of putting data on public and sharing photometry

with other groups. useful to decide strategy to catch rare short planetary deviation.

MOA-I (1999~2005)

（ Microlensing Observation in Antrophysics ）（ New Zealand/Mt. John Observatory, Latitude ： 44S, Alt: 1029m ）

MOA-I (1999~2005)

（ Microlensing Observation in Antrophysics ）（ New Zealand/Mt. John Observatory, Latitude ： 44S, Alt: 1029m ）

Mirror : 0.6mCCD : 4k 　 x 　 6k pix.FOV : 1.3 square deg.Seeing:~2 arcsec

Mirror : 0.6mCCD : 4k 　 x 　 6k pix.FOV : 1.3 square deg.Seeing:~2 arcsec

MOA-I filterMOA-I filter

Difference Image Analysis (DIA)Difference Image Analysis (DIA)

Observed Observed Observed Observed subtractedsubtractedsubtractedsubtracted

Results from MOA-IResults from MOA-I

Mass ： Jupiter Sep. : ~3AUMass ： Jupiter Sep. : ~3AU

1, Microlensing Optical depth towads GB (Sumi et al. 2003)

2, LP Variable stars in LMC (Noda et al. 2002,2004)

3, Stellar shape & limb darkning (abe et al.2003;Rattenbury et al.2005)

4, The first planet via microlensing (bond et al.2003) OGLE 2003-BLG-235/MOA 2003-BLG-53 (in collaboration with OGLE) etc…

1, Microlensing Optical depth towads GB (Sumi et al. 2003)

2, LP Variable stars in LMC (Noda et al. 2002,2004)

3, Stellar shape & limb darkning (abe et al.2003;Rattenbury et al.2005)

4, The first planet via microlensing (bond et al.2003) OGLE 2003-BLG-235/MOA 2003-BLG-53 (in collaboration with OGLE) etc…

LMC event from MOA-ILMC event from MOA-I(RA,DEC)=(05:13:48.7,-69:45:24.3)

T= 2,122 days

N= 3,743,244 stars

T= 2,122 days

N= 3,743,244 stars

tE=70.80umin=0.1754t0=1818.2308

RED

BLUE

LMC event from MOA-ILMC event from MOA-ItE=70.80umin=0.1754t0=1818.2308

RED

BLUE

Planetary transits in MOA-I Bulge data

Planetary transits in MOA-I Bulge data

• #of stars

<1.0 %: 0.1M stars

<2.0 %: 1M stars

Planning photometric follow-up by IRSF 1.4m IR telescope at SAAO

• #of stars

<1.0 %: 0.1M stars

<2.0 %: 1M stars

Planning photometric follow-up by IRSF 1.4m IR telescope at SAAO

MOA-II1.8m telescope（ New Zealand/Mt. John Observatory at NZ, 44S ）

Mirror : 1.8mCCD : 8k x 10k pix. FOV : 2.2 deg.2

Mirror : 1.8mCCD : 8k x 10k pix. FOV : 2.2 deg.2

First lightFirst light ：： 3/20053/2005Survey startSurvey start ：　：　 4/20064/2006

MOA-cam3CCD :8k x 10k pix. (10 E2V CCD4482)

Pixel size: 15μm FOV : 2.2 deg.2

CCD :8k x 10k pix. (10 E2V CCD4482)

Pixel size: 15μm FOV : 2.2 deg.2

MOA-II filterMOA-II filter

Observational time&Operation rateObservational time&Operation rate

Operation rate = observation time / night time ≒ clear time

BulgeBulge

Observation towards LMC by MOA-IIObservation towards LMC by MOA-II

~3obs/night~3obs/night

~10obs/night~10obs/night

Start alert in a few weeks

Discriminating fromSuper Nova

Discriminating fromSuper Nova

(from SuperMACHO web)(from SuperMACHO web)

Survey towards the Galactic BulgeSurvey towards the Galactic Bulge

• why ？• why ？

need Wide Field for Many stars need Wide Field for Many stars

　　　　　　　　 Probability:Probability:

　　　　 Microlensing : Microlensing : ~10~10-6-6 events/yr/starevents/yr/star　　　　　　　　 Planetary event : Planetary event : ~10~10-2-2

　　　　　　　　 Probability:Probability:

　　　　 Microlensing : Microlensing : ~10~10-6-6 events/yr/starevents/yr/star　　　　　　　　 Planetary event : Planetary event : ~10~10-2-2

G.C.G.C.G.C.G.C.SunSunSunSun

Time scale ~ 30days (MTime scale ~ 30days (M))

~ ~ a few daysa few days (M (MJupJup))

~ ~ hours hours (M (M)) need high cadence need high cadence

Observation towards the Bulge by MOA-II

Observation towards the Bulge by MOA-II

•50 deg.2

60GB/night

•1obs./hr (MJup)

1obs./10min. (M)

•50 deg.2

60GB/night

•1obs./hr (MJup)

1obs./10min. (M)

~~170170events (2006)events (2006)~~500500events (2007)events (2007)

http://www.massey.ac.nz/~iabond/alert/alert.html

Observational strategyObservational strategy

(Han (Han & Kim, 2001))

• High magnification event• we know when

• Low magnification event• rate is higher • we do not know when

• High magnification event• we know when

• Low magnification event• rate is higher • we do not know when

Example light curvesExample light curves• 〜５０ obs/

day

4days 4days

4days4days

Finite source effect （ MOA-2006-GLB-130 ）

Finite source effect （ MOA-2006-GLB-130 ）

Is=Is=21.07 mag

Real-time Anomaly check at Mt.JohnReal-time Anomaly check at Mt.John

anomalyanomaly

The first planet via microlensing OGLE 2003-BLG-235/MOA 2003-BLG-53

The first planet via microlensing OGLE 2003-BLG-235/MOA 2003-BLG-53

OGLE 2003-BLG-235/MOA 2003-BLG-53 was detected by the OGLE EWS System on June 22, 2003 andby the MOA group on July 21, 2003. 　

Mass ： Jupiter Sep. : ~3AU

5.5 Earth mass Planet (Beaulieu et al. 2006, Nature,439,437)

Sep~3AUSep~3AU

The smallest PlanetThe smallest Planet ！！

2nd & 3rd planets 2nd & 3rd planets OGLE-2005-BLG-071.

1 MJupiter , Udalski et al. 2005OGLE-2005-BLG-169,13MEarth,Gould et al.2006

“Cool Neptune" planets may be relatively common,

with frequency of >16% at 90% confidence.

High mag events in 2007High mag events in 2007High mag events in 2007High mag events in 2007

ttEE==6.240.15days,, A Amaxmax>>400

OGLE-2007-BLG-224(MOA-2007-BLG-163)

MOA-2007-BLG-312(OGLE-2007-BLG-388)

ttEE==3.500.65 days,, A Amaxmax==102

MOA-2007-BLG-397（ OGLE-2007-BLG-538 ）

ttEE==21.340.03 days,, A Amaxmax==404

MOA-2007-BLG-400ttEE==14.640.2 days,, A Amaxmax>>800800

Same field as ob349/mb379Same field as ob349/mb379

JD JD

JD JD

MOA-2007-BLG-192MOA-2007-BLG-192

q=q=6x10^-5, sep=, sep=0.9RE, 1.1RE,

MOAMOAOGLEOGLE

preliminarypreliminary

MOA-2007-BLG-197MOA-2007-BLG-197

1 年

q=3q=3x10-3, sep=, sep= 1RE

Orange: PLANET (Danis)Orange: PLANET (Danis)Blue : PLANET (Tasmania)Blue : PLANET (Tasmania)Red :PLANET SAAORed :PLANET SAAOBrown : MOABrown : MOA

preliminarypreliminary

OGLE-2007-BLG-368 (MOA-2007-BLG-308)OGLE-2007-BLG-368 (MOA-2007-BLG-308)

q=~q=~1x10^-4

MOAMOAOGLEOGLEPLANET(Danish)PLANET(Danish)PLANET(Tasmania-I)PLANET(Tasmania-I)PLANET(SAAO-I)PLANET(SAAO-I)PLANET(Brasil)PLANET(Brasil)FUN(CTIO-I)FUN(CTIO-I)

OGLE-2007-BLG-349 (MOA-2007-BLG-379)OGLE-2007-BLG-349 (MOA-2007-BLG-379)

q=q=2.8x10^-4, sep=, sep= 0.8RE

VLTVLTHSTHSTImages are Images are

takentaken

preliminarypreliminary

Summary of Planet candidatesSummary of Planet candidates

preliminary. Credit Bennett

Gould et al. 2006:“Cool Neptune" planets may be relatively common with frequency of >16% at 90% confidence.”

Also consistent with formation theory. (Ida & Lin, 2004)

Number of planets via MicrolensingNumber of planets via Microlensing

0

1

2

3

4

5

2003 2004 2005 2006 2007

publishedsubmittedin preparation

Free floating planet candidatesFree floating planet candidates

tE=1.2days

prel

imin

ary

Free floating planet candidatesFree floating planet candidates

tE=1.2days

prel

imin

ary

Nmodel(tE<5) = 0.7(Scalo)Nobserv(tE<5) = 4

54 events in1/3of all fields In 2006

prel

imin

ary

Kamiya et al in preparation

SummarySummary• We are working hard to finish MOA-I

• MOA, OGLE, PLANET and μFUN found ~5 exoplanets candidates via microlensing in 2007. (in preparation)

• Consistent with Gould et al. 2006: “Cool Neptune planets may be

relatively common”

• Planet event rate increasing to ~4 planets/yr by all microlensing community’s effort.

• MOA-II demonstrated the power of wide FOV high cadence survey. OGLE-IV （ & new Korean telescopes ） Global Wide FOV network for 24hrs

• We are working hard to finish MOA-I

• MOA, OGLE, PLANET and μFUN found ~5 exoplanets candidates via microlensing in 2007. (in preparation)

• Consistent with Gould et al. 2006: “Cool Neptune planets may be

relatively common”

• Planet event rate increasing to ~4 planets/yr by all microlensing community’s effort.

• MOA-II demonstrated the power of wide FOV high cadence survey. OGLE-IV （ & new Korean telescopes ） Global Wide FOV network for 24hrs