Rachel Bezanson Hubble Fellow, Steward Observatory - University of Arizona

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Adrian Bennett
7 years ago
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1 Following Massive Galaxies through Cosmic Time - Structures, Absorption Line Kinematics, & Scaling Relations since z~2 Rachel Bezanson Hubble Fellow, Steward Observatory - University of Arizona in collaboration with: Pieter van Dokkum, Marijn Franx, Jesse van de Sande, & Mariska Kriek and the NMBS, UDS and 3D-HST collaborations Oxford Galaxy Masses Conference - July 2014

2 Essentially all easily observable properties of massive galaxies have changed since z~2 z ~ 0 z ~2 higher masses larger red & dead stellar pops ellipticals (de Vaucouleurs profiles) less massive smaller many still star forming lower Sersic indices (more disklike?) How should we follow galaxy populations through time?

3 WHY? Measuring Dynamics Velocity dispersion is the most stable property for individual galaxies in two-phase galaxy evolution Related to stellar populations Ages, abundances, (SFR) σ! Velocity dispersion related to IMF IMF slope! Dynamics can verify compactness! (mostly) direct comparison to simulations σ... and so on... Stellar Mass (from SEDs) Dynamics can test stellar mass estimates Dynamical Masses

4 Scaling Relations... Because directly measuring dynamics is EXPENSIVE! this talk: 1) evolution of the (mass) fundamental plane 2) using the mass fundamental plane for evolving populations of massive galaxies

5 Adding a 3rd dimension to the structural evolution of massive galaxies The Fundamental Plane SDSS galaxies! 0.05 < z < 0.07! Simard+11 Sersic Fits! Graves+07 red sequence Hyde & Bernardi, 09 FP R e / 1.40 I 0.76 e

6 The Fundamental Plane Evolves as quenched galaxies fade with time High-z Galaxies! Wuyts+2005 van der Wel+2005 van Dokkum+2009 Newman+2010 Bezanson+2013 van de Sande+2013 see e.g. van Dokkum & Franx 1996 Treu van Dokkum & van der Marel 2007 Holden+2010 Toft+2012 and many more! Bezanson+13b

7 The Fundamental Plane Evolves as quenched galaxies fade with time Is all evolution due to M/L evolution with age? Could also be due to e.g. size evolution (Saglia+10)... and stay tuned for new results from van de Sande et al., submitted Bezanson+13b

8 The Fundamental Plane Tilted with respect to Virial Plane Tilt of the Fundamental Plane due to M/L variation within the plane M/L / L 0.24 (e.g. Faber, 1987) Hyde & Bernardi, 09 FP R e / 1.40 I 0.76 e Virial Plane R e / 2 I 1 e also suggested: non-homology in surface brightness distribution and/or kinematics or variations in dark matter fractions (e.g., Renzini & Ciotti 93; Prugniel & Simien 94, 96, 97; Ciotti+96; Graham & Colless 97; Forbes+98; Bertin+02; Borriello+03; Trujillo+04)! Review talk by Cappellari on Monday!

9 The Mass Fundamental Plane surface brightness stellar mass surface density *also Schechter s talk on Wednesday Spectral Energy Distribution (SED) stellar M/L Whitaker+11 Bezanson+13b Hyde & Bernardi, 09 mass FP R e / e

10 The Mass Fundamental Plane remarkably stable! Bezanson+13b

11 How simple is galaxy evolution? Virial Plane R e / 2 1 Hyde & Bernardi, 09 mass FP R e / e the mass FP nearly the Virial plane

12 The classical FP for quiescent galaxies evolves strongly but the mass FP is remarkably stable Luminosity FP Residual Stellar Mass FP Residual Redshift Redshift M/L evolution can explain the luminosity FP evolution! Bezanson+13b

13 What about massive galaxies that have not yet quenched or don t otherwise fit? SHAPE?! COLOR?! ROTATION?

14 What about massive galaxies that have not yet quenched? Traditional FP SDSS > 100km/s combination of rotation and dispersion, measured from absorption line kinematics Quenched Galaxies Star- Forming Galaxies Different Stellar Populations imply different M/Ls - offset FP

15 Star Forming and Quiescent Massive Galaxies Lie on the Same Mass Fundamental Plane Mass FP SDSS > 100km/s Traditional FP SDSS z ~ 0.7 Bezanson+in prep

16 A(nother*) Poor Astronomer s Velocity Dispersion *also e.g. Faber s Talk on Monday: 1kpc Velocity Dispersion from Stellar Mass Faber-Jackson Velocity Dispersion from Stellar Mass Fundamental Plane log Inferred σ log Inferred σ log Measured σ log Measured σ

17 Even More Poor Astronomer s Velocity Dispersions: Must include Sizes Fundamental Plane Virial Theorem Virial Theorem, including structural non-homology* log Inferred σ log Inferred σ log Inferred σ log Measured σ log Measured σ Scatter in each ~ 0.07 dex log Measured σ *K(n) from Cappellari+06

18 ... to be continued! What is the effect of a non-universal IMF on the mass FP? What are the effects of non-homology/dark matter fractions? Where does this break down?? Larger, more representative spectroscopic samples at z>0 Summary: Despite the observed evolution of massive galaxies, the relation between structures and dynamics of quenched galaxies is strikingly stable Galaxy evolution follows the Virial theorem (to first order) Massive (velocity dispersion > 100km/s) starforming AND quiescent galaxies follow the same mass fundamental plane

Arjen van der Wel -- MPIA, Heidelberg

THE PATH FROM COMPACT Z = 2 GALAXY TO GIANT ELLIPTICAL Arjen van der Wel -- MPIA, Heidelberg with the 3D-HST and CANDELS teams THE PATH FROM COMPACT Z = 2 GALAXY TO GIANT ELLIPTICAL The size-mass relation