Quenched and Quenching Galaxies at Low to High Redshifts S.M. Faber & UCSC and CANDELS collaborators Dekel60 Fest December 13, 2011 M31: UV GALEX

Quenching Scenarios for Central Galaxies Halo-based  Massive halo quenching: “cold flows” to hot halos + AGN (“radio mode”) Bulge-building  Major merger -> starburst + AGN  Minor mergers + AGN  Disk instability + AGN  Disk secular evolution + AGN  Morphological quenching (Toomre Q) Hopping/rejuvenation  Mergers  Stochastic accretion Correlate with galaxy properties Correlate with halo properties

Part I: Quenching of central SDSS galaxies at z ~ 0 with halo mass vs. stellar mass Joanna Woo & Avishai Dekel Joanna 

Probability of quenching vs. M* and M halo Woo et al  Contours run vertically.  Quenching correlates better with halo mass than with stellar mass.

Part II: HST UV images of nearby Green Valley galaxies Jerome Fang, Samir Salim, S. M. Faber, et al. Jerome 

HST UV images of SDSS green valley galaxies Fang, Salim et al  20 galaxies imaged with HST SBC.  Sample lies in bluer part of green valley.

HST FUV images Fang, Salim et al. 2011

HST sample vs. general green valley Fang, Salim et al  Many more GV galaxies with similar properties.

Colors imply underlying substrate of older stars Fang, Salim et al ESFETGs Mass- matched in blue cloud Fang, Salim et al. 2011

HST FUV images Fang, Salim et al. 2011

GALEX: M31

Part III: Structure of AEGIS galaxies on Red Sequence vs. Blue Cloud at z ~ 0.8 Edmond Cheung, Liz McGrath, & David Koo Edmond 

Try different combinations of mass and radius Cheung et al DEEP2 survey: spec z’s and photoz’s. Redshift range z = MassM/r eff M/r eff 2

None work perfectly. There is always overlap region. Cheung et al DEEP2 survey: spec z’s and photoz’s. Redshift range z = MassM/r eff M/r eff 2 Surface density Kauffmann+06

Try different combinations of mass and radius – None work perfectly Cheung et al DEEP2 survey: spec z’s and photoz’s. Redshift range z = MassM/r eff M/r eff 2 Effective velocity Franx+08

Cheung et al Is there a second structural variable? Cheung et al DEEP2 survey: spec z’s and photoz’s. Redshift range z =

U-B Bulge M* is higher Bulge radius is smaller Bulge M*/r e is lower Cheung et al AEGIS galaxies have bulge-disk decompositions using GIM2D. In the overlap region, the color change is accompanied by structural changes. Stellar mass becomes more concentrated.

Sersic index: looks like a threshold, except for outliers Cheung et al outliers See also Bell+08, Bell+11

Inner mass surface density increases across color divide McGrath, Koo et al  Rejuvenation model no good; one way trip  Structure is better predictor of quenching than halo or stellar mass

Part IV: Pre- and post-quenched galaxies in CANDELS at z ~ 2 Mark Mozena, Tao Wang, JS Huang, and CANDELS team Mark 

Color-mass diagram: CANDELS/ERS in GOODS-S ✖ Spheroid ✖ Mixed or Irr ✖ Disk Z = Mozena et al Visual classes: Note color-mass relation already at z~2!

Massive galaxies > M  at z~2 in Gini/M 20 Quiescent Star-forming Wang et al  Half quenched, half star-forming.  Strong correlation with morphology.  These SFR galaxies will all be quenched by z~1. WFC3-IR images from CANDELS and ERS in GOODS-S

Radius-mass diagram: GOODS-S ✖ Spheroid ✖ Mixed or Irr ✖ Disk Z = Mozena et al Also Cirasuolo et al Visual classes:

Radius-mass diagram: GOODS-S ✖ Spheroid ✖ Mixed or Irr ✖ Disk Z = Mozena et al Also Cirasuolo et al Visual classes: Almost bimodal!

Radius-mass diagram: GOODS-S ✖ Spheroid ✖ Mixed or Irr ✖ Disk Z = Mozena et al Also Cirasuolo et al Visual classes: X5

Conclusions: There exist structural parameters that are better predictors of quenching than either halo or stellar mass. An indispensible ingredient in the quenching process at all redshifts is either caused by (or leaves its imprint on) the stellar mass distribution – stars move to center. At low z, this process does not involve major mergers or a large change in radius. At high z, gross shrinkage in radius of x5 occurs. Is the process the same or different at high z?