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Galactic Astronomy 銀河物理学特論 I Lecture 3-5: Evolution of dynamical structure of galaxies Seminar: Forster Schreiber et al. 2009, ApJ, 706, 1364 Lecture:. 2012/01/30. 0<z<1: Morphology of z~1 star-forming galaxies (Luminous IR Galaxies). Rest-B. 5 arcsec. Konishi et al. 2011, PASJ, 63, 363.
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Galactic Astronomy銀河物理学特論 ILecture 3-5: Evolution of dynamical structure of galaxiesSeminar: Forster Schreiber et al. 2009, ApJ, 706, 1364 Lecture: 2012/01/30
0<z<1: Morphology of z~1 star-forming galaxies (Luminous IR Galaxies) Rest-B 5 arcsec Konishi et al. 2011, PASJ, 63, 363
● LIRG disk▲LIRG bulge ○ non-LIRG disk△non-LIRG bulge ●X-ray 0<z<1: Morphology of z~1 star-forming galaxies (Luminous IR Galaxies) • SFR fraction (●:▲:○:△) 0.64:0.14:0.19:0.03 • For galaxies with SFR > ~ 19 Msun yr-1 (24 mm limit), 70% are LIRGs . • No active star formation among non-LIRG bulge dominated galaxies 24 mm completeness limit Sbc-Sd S0/a-Sb E/S0 SDSSemlines LIRGs dominate star formation rate density z ~ 1. Ms ≥ 1010 Msun LIRGs have morphologies similar to disk galaxies Konishi et al. 2011, PASJ, 63, 363
Between 0<z<1 : Disk galaxies : Disk-size • 0<z<1: Size evolution of disk galaxies • The absolute magnitude – size relation (i.e. surface brightness) shows evolution but no evolution in the stellar mass – size relation (i.e. surface stellar mass density) (Barden et al. 2005, ApJ, 635, 959)
Between 0<z<1 : Disk galaxies : Disk dynamics • 0<z<1: Evolution of the Tully-Fisher relation • Disk galaxy dynamics with VLT/GIRRAFFE multi-IFU w/o AO • Flores et al. 2006, A&A, 455, 107 (0.4<z<0.75, disk galaxies), 35% pure-rotating disks following local-TF relation, 65% disturbed rotation, complex kinematics ? • IMAGES: Yang et al. (2008, A&A, 477, 789), Neichel et al. (2008, A&A, 484, 159), Puech et al. (2008, A&A, 484, 173) • Neichel+08 : 12/22 spiral morphology galaxies have PR or CK velocity fields • Peuch+08 : 2 times increase of stellar mass necessary to match the local K-band TF relation ? Velocity dispersion ratio between model and observation at the model peak position Yang+08; RD (blue), PR (green), CK (red) Puech+08; Solid line: local TF relation Distance between model and observed peaks of velocity dispersion (pixel=0.52”)
0<z<1 : Disk galaxies : Bar-fraction • Sheth et al. (2008, ApJ, 675, 1141)COSMOS HST images sample • Fraction of barrd spiral galaxies (bar-fraction) shows rapid increase between z=1 and 0. • The increase is more rapid for galaxies with smaller stellar mass. Black: z=0.14-0.37 Blue: z=0.37-0.60 Red: z=0.60-0.84
0<z<1 : Early-type (E+S0) galaxies • Treu et al. 2005, ApJ, 633, 175, 0.2<z<1.2 field E+S0 (GOODS-N) • Offset from local FP (sigma-SB-Re) is d(logM/L)/dz=-0.4 for logM* >11.5 and 0.5>d(logM/L)/dz>-1 for logM*<11. Such offsets are consistent with passive evolution with zf=5 and zf=1-2, respectively. • E+S0 galaxies in clusters of galaxies show offset of d(logM/L)/dz=-0.46, larger evolution than field samples. • van der Wel & van der Marel (2008, ApJ, 684, 260) 0.6<z<1.2 field E+S0 • (V/sigma)* vs. MB relation and (V/sigma)* vs. Ellipticity relation can be explained with passive evolution models. • Fainter elliptical galaxies show larger fraction of galaxies with large (V/sigma)* and large ellipticity. • van der Wel et al. (2008, ApJ, 688, 48) 0.8<z<1.2 field+cluster E+S0 • Evolution of the Re vs. Mdyn relation. Re is about half at the same Mdyn.
Between 0<z<1 : Disk galaxies : Disk dynamics IFU (+AO) spectroscopic observations of high-redshift galaxies: image slicer VLT SINFONI
Z~3 ; structure • Most of the LBGs (+an RadioG +DRGs) are fitted well with Sersic profiles with n<2. (Akiyama et al. 2008, ApJS, 175, 1)
Z~3: Dynamics • Stark et al. 2008 Nature, 455, 755; z=3.07 lensed galaxy • Thanks to gravitational lensing and LGSAO, effective spatial resolution was very high (20-40mas = 150-300pc resolution) . Smooth velocity shear field support the rotational structure of the galaxy. • +-50km/s rotation (inner 0.5kpc) + flat rotation curve, logMdyn=9.3 vs. logMstr=9.8 • Sigma=54km/s, v/sigma=1.2 (heating by star-formation activity ?), • 4.4 Msolar/yr/kpc2 (Similar to nuclear Star burst in local galaxies) • 12+log(O/H)=8.6 = 0.9Zsolar, • CO luminosity-gas mass conversion factor <0.8; ~local LIRG (1) << local spiral (5)
Z~3: Dynamics • Law et al. (2009, ApJ, 697, 2057) • 12 galaxies at z=2.0-2.5 and 1 galaxy at z=3.3 ([OIII]) observed with Keck LGS-AO (typical resolution 0.15”) + OSIRIS with 1.0-4.5hours with 100/150mas FWHM (50mas sampling). Mean velocity (black) vs. velocity dispersion (red)
Z~3: Dynamics • Law et al. (2009, ApJ, 697, 2057) V(shear) as a function of stellar mass. Horizontal dashed line represents the typical velocity dispersion (70km/s). V(shear) as a function of gas mass fraction (Mgas/(Mgas+Mstar), Mgas estimated with Ha luminosity)
Z~3 : Summary I • Rotation supported or velocity dispersion supported ? • Large stellar mass galaxies are rotation dominated ? • Large velocity dispersion imply large Jean’s mass resulting big star-forming complexes (Elmegreen et al 2008, next slide). • Thick disk ? : hz/R = 0.5(sigma/v)^2 • Toomre’s Q parameter is small : globally-unstable disks. • Q= sigma k / 3.36 G Sigma • MW: sigma=30km/s, Sigma=50Msolar/pc^2, k=36km/s/kpc -> Q=1.4 • High-z: sigma=50-100km/s, Sigma=300Msolar/pc^2, k=V/R=30km/s/kpc resulting Q=0.2