PPTVIEW

Size: px

Start display at page:

Download "PPTVIEW"

あゆみみうら
5 years ago
Views:

1 重力マイクロレンズ ( ダークマターと銀河構造 ) 銀河系ハロー銀河系中心部住貴宏 ( 名古屋大学 ) the MOA collaboration

2 Gravitational Macro lensing

3 Gravitational Macro lensing

4 Gravitational Micro lensing μas M lens ~M 離隔 ~μarcsec 増光だけ見える Magnification time (day)

5 Plastic lens

6 Single lens

7 Extra galactic マイクロンズの応用 1,(QSO variability etc.) Galactic 1, 銀河ハローダークマター (towards the LMC & SMC) 2, 銀河構造 (towards the Bulge) 3, 系外惑星 (towards the Bulge)

8 WMAP が明らかにした宇宙宇宙の姿ダークエネルギー Ω Λ =0.74 ダークマター DM =0.22 Ω DM Ω B =0.04 バリオン 4%: Stars: 7% Neutral gas: 2% Cluster hot gas: 3% Unknown (warm gas?): 88%

9 銀河の回転曲線とダークマター Dark Matter Kepler: v 2 =GM/r

10 Halo Dark Matter & Paczynski s Idea times more dark matter than visible mass. MAssive Compact Halo Objects (MACHOs) WINPs MACHO can be observed by Microlensing.(Paczynski 1986) τ 万個の星をみればよい!

11 MACHO project (1990~2000) 1.28m telescope 1.8 million stars

12 First Microlensing event by MACHO & EROS in 1993

13 LMC 方向の結果 MACHO 5.7 yrs: 12 events M~0.5M 16% of the mass of a standard Galactic halo. EROS 5yrs : 0 event f<25% of the halo dark matter made of MACHO with M f< 10% for M. Tisserand et al.2006

14 つまり MACHOs はハローダークマターの主成分ではないしかし MACHOs が可視物質と同じ位ある!?

15 パラメーターの縮退観測値イベントタイムスケール :

16 つまりマゼラン雲方向にレンズ天体はあるしかし本当にハローにあるか?

17 Halo Dark Matter? or Self-lensing?

18 MEGA project アンドロメダ銀河 (M31) 14 events f<30%

19 SuperMACHO 4m telescope, 1/2 nights for 3 months over 5 years. ~30events Self-lensing lensing in LMC Event rate Halo MACHO Center Outer 最新結果 (preliminary): 25イベント (microling+sn) Self-lensing は無視出来る程度 f<30%

20 SuperMACHO v.s. Super Nova

21 MOA (since 1995) (Microlensing Observation in Astrophysics) ( New Zealand/Mt. John Observatory, Latitude: 44 S, Alt: 1029m ) キャンペーン期間中 (5/2-5/4): 今 MOAグループに加入するともれなくエアー NZ で行く楽しい NZ ランド 27 泊 28 日の旅をプレゼント応募は sumi@stelab.nagoya-u.ac.jp まで

22 MOA (since 1995) (Microlensing Observation in Astrophysics) ( New Zealand/Mt. John Observatory, Latitude: 44 S, Alt: 1029m ) 1995~1998:MOA-0: 0.6m, 9Mpix 1999~2005:MOA-I : 0.6m, 24Mpix 2005~ :MOA-II: 1.8m, 80Mpix

23 MOA(until ~1500) (NZ にいた世界最大の鳥 ) height: 3.5m weight: 240kg 飛べない 500 年前に絶滅 (Maori が食べ尽くした ) ~1850 まで目撃証言あり!?

24 MOA-II1.8m 望遠鏡主鏡 : 1.8m CCD : 80 メガピクセル視野 :2.2 平方度ファーストライト : 2005/3 サーベイ開始 : 2006/4

25 event rate: Observational targets LMC,SMC : ~2 events/yr (τ~10-7 ) Bulge : ~500events/yr (τ~10-6 ) 10-2 Planetary event : ~10 Planetary event : ~10-2 8kpc, GC 50kpc LMC

26 Observation towards LMC by MOA-II ~3obs/night ~10obs/night

27 Difference Image Analysis (DIA) Observed subtracted

28 まとめ 1 MACHO はダークハローの主成分ではない (<20%) マゼラン雲方向にレンズ天体はあるしかしハローにあるか? MOAII が 5 年後に制限をつける

29 < 銀河ハローハロー内 > 重力レンズレンズによる制限 EROS and MACHO (LMC) Variability in lensed QSO Schmidt et al 98 M<10-7 or 10-1 <M 運動学的制限 (Carr & Sakellariadou 99) 天の川銀河川銀河の定常性 + 普遍性を仮定! 散開星団球状星団球状星団の破壊 M<10 3, M>10 6 連星の破壊 M<10 0, M>10 7 太陽系天体に対するする影響地球とのとの遭遇 10-3 影響 M<10 M>10-13 halo M>10-12 disk

30 Microlensing of QSOs image A macrolens QSO image B microlenses

31 SUb-Lunar-mass Compact Objects (SULCOs) Log(M/M s ) Log(Ω CO ) -1-2 γ Unconstrained MACHO CDM = SULCOs <M<10-7?

32 < 宇宙内 > Current limit on compact objects in universe from lensing studies (1)microlensing of QSO Dalcanton, et al 94 (2,4)multiple image of compact radio sources.wilkinson et al 01 Augusto 01 (3)multiple gamma-ray bursts Nemiroff et al 01 (5)multiple image of QSO Nemiroff 91 M<10-3 or 10 1 <M<10 4

33 2 つの窓 SUb-Lunar-mass Compact Objects (SULCO) MAssive Stellar-mass Compact Objects (MASCO) (10-13 ) <M< <M< 10 4 planetesimal, PBH primordial stars, BH, PBH

34 Microlensing by SULCOs in Galactic halo M33 D M33 = 790kpc Inner Oort cloud comets KBOs (Total event) ~10 3 for 10-8 M s, ΔΤ 10 3 sec ~1 for M s, ΔΤ 1sec For 80hours obs. by SUBARU/Suprime-cam

35 Direct mapping of MASCOs image A macrolens source image B microlenses micro-images

36 MASCOs M=10 3 if Ω MASCO =Ω m 2.5mas A B C D N=1.7(M/10 4 ) -1 mas -2 Inoue & Chiba ApJ 03

37 銀河中心のはなし

38 Optical Gravitational Lensing Experiment (OGLE) Las Campanas Altitude: 2300m Seeing ~ 1.3 OGLE-I : 1991~1996 : 1m, 2kx2k CCD 19 events OGLE-II : 1997~2000 : 1.3m, 2kx2k CCD, 14 x events OGLE-III: 2001~ : 1.3m, 8kx8k mosaic CCD 600 events/yr : 35 x35

39 the Galactic Bar structure Obs. 8kpc φ (face on, from North) G.C.

40 Candidates Level 5: 66/122 candidates are selected. (degenerated events are removed, t E u min ~const).

41 Obs. the Galactic Bar structure 8kpc 1, Microlensing Optical depth, τ φ (face on, from North) G.C. (Alcock et al. 2000; Afonso et al.2003; Sumi et al. 2003;Popowski et al. 2004; Hamadache et al. 2006;Sumi et al. 2006) M= M, axis ratio (1:0.3:0.2), φ~20

42 2.Red Clump Giants Metal-rich horizontal branch stars Small intrinsic width in luminosity function (~0.2mag) φ=20-30, axis ratio 1:0.4:0.3 Stanek et al. 1997

43 Measurements of streaming motions of the Galactic bar with RCG Sumi (Princeton), Eyer (Geneva Obs.) & Wozniak (Los Alamos), 2003 Sun faint bright Idea, Mao&Paczynski, 2002

44 3.Proper motion ~300 I-band frames, 4years ~1mas/yr

45 Streaming motions of the bar Color Magnitude Diagram Sun faint bright Vrot=~50km/s Sumi, Eyer & Wozniak, 2003

46 <t E >=28 days Event Time scale Evans & Belokurov (2002): t E =14, no stream t E =45, vrot=50km/s Sumi et al. 2004

47 まとめ 2 All three results are consistent with the Bar with M= M, axis ratio (1:0.3:0.2) φ=20, (Han & Gould, 1995) V rot ~50km/s Little space for Dark Matter Prefer Core than cusp dark matter (Binney & Evans 2001) MOA が制限を強くする! ρ r -α

48 Cusp-Core problem in the CDM halo 銀河銀河団の密度プロファイル : 中心部はカスプ ρ r -1.5 を持つかあるいはコア ρ 一定になっているか? Simulation: NFW universal density profile ρ r -1.5 (Navarro, Frenk& White 1997) with central cusp rather than core Collisionless cold dark matter: reproduces nicely the observed large scale structure of the universe (r>>1mpc) Observation: rotation curve for CDM dominated Dwarf and low surface brightness (LSB)galaxies have a density profile with flat central core.

49 Cusp-core problem in dwarf spirals to giant low surface brightness galaxies (CMD dominated in center) Light curve of dwarf spiral DDO47 Cusp (NFW) Dark halo density in ESO 116+G12 Observed simulation (NFW) Core Prefer core (Moore et al. 1999; de Blok et al. 2000; Salucci & Burkert 2000;Salucci&Martin 2009)

50 Cusp-core problem:solution Self interacting dark matter(spergel & Steinhardt 1999 ): σ/m~1cm 2 /g make core and spherical halo (Yoshida etal. 2000)

52 Typical WIMP WIMP elastic scattering cross section ~10 40 cm 2 and mass GeV; for halo density ~GeV/cm3 and velocity ~300 km/sec sec, mean free time for WIMP scattering is at least /H 0 ; thus, WIMPs act as collision free dark matter. Axion axion cross section far smaller, so also collisionless.

53 Cusp-core problem in giant elliptical galaxies; (Baryon dominated in center ) Lensing image in (Koopmans 2003) Observed galaxy subtracted Lensing probability with image separation Δθ (Lin & Chen 2009) Singular isothermal sphere Observation Cusp (NFW) Cusp, ρ r -1.9 Core Prefer cusp

54 Cusp-core problem in giant elliptical galaxies; (Baryon dominated in center ) Statistics of QSO multiple images (Wyithe Wyithe, Turner &, Spergel 2001; Keeton & Madau 2001; Li & Ostriker 2001; Takahashi & Chiba 2001) Arc statistics of clusters of galaxies (Bartelmann et al. 1998; Molikawa & Hattori 2001; Oguri, Taruya + Suto 2001, Oguri, Lee + Suto 2003) Time Time-delay statistics of QSO multiple images (Oguri, Taruya, Suto + Turner 2002) generally favor a steep cusp ( α~ -1.5)

55 Cusp-core problem: solution Barion-CMD interaction (BCMDIs) Dynamical friction of substructure (El-Zant et al.2001;tonini et al., 2006;Romano-Diaz et al.2008) Stellar bar-cdm interaction (Weinberg&Katz, 2002;Holley-Beckelmann et al.2005) Baryon energy fedback(mashchenko et al., 2006; Peirani et al. 2008) Nonsingular, trancated isothermal sphere (NTIS) Cosmological, from from collapsend virialization (shapiro et al. 1999; Iliev&Shapiro, 2001) Explain core in rotation curves, but cannot explain the steep & cuspy center of massive galaxies favored by Lensing and X-ray observation.

56 まとめ MACHO は Dark Halo の主成分でないけど何かある我々の銀河中心の dark matter は cusp でなく core である

57 end

58 Extra-Solar Planet via Microlensing

59 Planetary lens

60 2 nd Exoplanet Discovery by μlensing OGLE 2005-BLG-71 (Udalski, Jaroszynski, et al - OGLE & μfun. Addl data from MOA & PLANET). M p =0.35M J, Sep=3.6AU Data from OGLE, μfun, PLANET & MOA amateur astronomers

61 それぞれ得意な領域がある視線速度 : 高検出効率トランジット : 惑星の半径直接撮像 : やっぱ直接はすごいマイクロレンズ : 主星の明るさにるさに依存しない! 長軌道半径惑星 : スノーライン外側軽い惑星 : 地球質量暗い主星 : M-dwarf 遠い主星 : 銀河内分布浮遊惑星 : 主星なし

62 まとめマイクロレンズで 8 個の系外惑星 (7 惑星系 ) を発見太陽系に良く似た惑星系を発見褐色矮星質量程度の主星に系外惑星を発見 M-dwarf で超軌道半径の巨大ガス惑星を発見 M-dwarf では Cool Neptune は非常に一般的 ~40% に存在 (>16% at 90% confidence) at 1.5-4AU. 巨大ガス惑星の約 3 倍銀河中心では惑星系は少ない!? Thick disk で発見

63 The Microlensing Planet Finder (MPF) David Bennett, Science PI

dark matter density profiles

dark matter density profiles LSS & CDM 2 LSS & CDM 3 SPH simulation: movie SPH simulation in CDM : dark matter hot gas galaxy (Yoshikawa, Taruya, Jing & Suto 2001) LSS & CDM 4 Confronting elements of the CDM paradigm Global cosmological