MUSYC E-HDFS UBR composite Formation and Clustering of High-redshift Galaxies 2. Galaxy Formation Eric Gawiser Rutgers University

What Do We Know About Galaxy Formation? Recently Solved Problems Integral Constraints Protogalaxy Demographics

Recently Solved Problems in Galaxy Formation Initial Conditions: WMAP cosmology CMB + galaxy P(k) + Type Ia SNe    =0.7,  m =0.3,  b =0.04, H 0 =70 km/s/Mpc

Recently Solved Problems in Galaxy Formation Initial Conditions: WMAP cosmology Final Conditions: Low-z galaxies Well-studied in MW and nearby galaxies

Recently Solved Problems in Galaxy Formation Initial Conditions: WMAP cosmology Final Conditions: Low-z galaxies Integral Constraints: Cosmological quantities Baryon budget: Star Formation Rate Density (SFRD) is integral constraint over space at a given time (M  /yr/Mpc 3 )  gas (t)=  gas,0 -  0 t d  * /dt), Gas Density (  gas (t)=  gas,0 -  0 t d  * /dt),  * (t)=  0 t d  * /dt), Stellar Mass Density (  * (t)=  0 t d  * /dt), Metal Density (  * (t)=1/42  0 t d  * /dt) are integral constraints on SFRD over time CIB + FIRB constrain integrated SFRD to z=0

Recently Solved Problems in Galaxy Formation Initial Conditions: WMAP cosmology Final Conditions: Low-z galaxies Integral Constraints: Cosmological quantities Identified Galaxy Zoo at z=3 Lyman break galaxies, Lyman alpha emitters, Distant red galaxies, Active Galactic Nuclei, Damped Lyman alpha systems, Submillimeter galaxies However: Evolutionary sequence unclear, progenitors of typical galaxies like the Milky Way yet to be identified

Galaxy Formation Models Monolithic Collapse Eggen, Lynden-Bell & Sandage 1962 Gravitational collapse of cloud of primordial gas Thus all parts of galaxy formed at the same time Happened very early in the lifetime of the Universe Hierarchical Formation (CDM) Small clumps of matter merge together to form larger galaxies Happens throughout the lifetime of the Universe Thus formation of galaxies is an ongoing process

Hierarchical Structure Formation No preferred scales in DM but non-linear collapse gives distribution of halos where galaxies can form Small halos collapse first  “bottom-up” At z>2, galaxy-mass halos are rare so majority of halos collapsed recently Galaxies have M max and M min Scales come from “gastrophysics” of virialization and feedback from supernovae and supermassive black holes Dark energy produces cosmological “freeze-out” - structure stopped forming at z eq ~0.3 Galaxy formation freeze-out occurred earlier in massive galaxies  “downsizing” (anti-hierarchical?)

Why high redshift? Galaxy formation hard to study in local universe High-z = Jurassic Park of galaxies Nature Sep. 14, 2006

AGN with Damped Lyman  Absorber (DLA) DLAs have N(HI)>2x10 20 cm -2, sufficient to self-shield against (re)ionization Provide unbiased sample of lines of sight through the cosmos out to quasar Lower column density systems are ionized  DLAs dominate neutral gas content

Cosmic density of neutral gas Wolfe, Gawiser & Prochaska 2005, ARAA Neutral gas reservoir traced by DLAs is depleted by z=0 HI (21cm) HI (DLAs)  gas (x10 -3 )

History of neutral gas Closed box: d  gas /dt =-d  * /dt

Cosmic density of neutral gas Wolfe, Gawiser & Prochaska 2005, ARAA Neutral gas reservoir traced by DLAs is depleted by z=0 HI (21cm) HI (DLAs)  gas (x10 -3 )

Cosmic density of neutral gas Wolfe, Gawiser & Prochaska 2005, ARAA Neutral gas reservoir traced by DLAs is depleted by z=0, forming >~ half of the stars seen today HI (21cm) stars HI (DLAs)  gas (x10 -3 )

History of neutral gas Closed box: d  gas /dt =-d  * /dt

History of neutral gas Closed box: d  gas /dt =-d  * /dt Open box: d  gas /dt =-d  * /dt + infall + merging - winds

Cosmic density of neutral gas Wolfe, Gawiser & Prochaska 2005, ARAA Neutral gas reservoir traced by DLAs is depleted by z=0, forming >~ half of the stars seen today HI (21cm) stars HI (DLAs)  gas (x10 -3 )

Cosmic star formation history 16% of cosmic age Giavalisco et al z>3 points from Lyman break galaxies only Solid blue curve: semi-analytic model of Somerville et al. 2001

Most stars formed at z<2 Pettini 2003

 * (t)=  0 t d  * /dt Stellar mass density  * (t)=  0 t d  * /dt Dust extinction less problematic, but need to know IMF and star formation history Dickinson et al 2003

 * (t)=1/42  0 t d  * /dt Cosmic metal enrichment history  * (t)=1/42  0 t d  * /dt Cosmic metallicity traced by DLAs rises gradually Wolfe, Gawiser & Prochaska 2005, ARAA

DLA metallicities in context Pettini 2003

Evidence for dust depletion and alpha enhancement in DLAs

DLA Kinematics: Disks or Clumps?

Theoretical Advances Semi-analytical models reproduce observations moderately well Cosmological hydrodynamic simulations have advanced greatly - but use recipes for star formation and supernova feedback

Cosmological hydro simulations Nagamine et al M=10 10 M 

Hydro simulation of SFR history as a function of mass using “recipes” Nagamine et al. 2003

Demographics of Protogalaxies Searching for the progenitors of typical galaxies like the Milky Way - are they found amongst the zoo of objects at z=3? Cosmological quantities (SFR, stellar mass buildup) should be summed over all high- redshift objects, not just DLAs, which trace the low-dust neutral gas, or LBGs, which trace the bright end of the luminosity function

MUSYC ( Multiwavelength Survey by Yale-Chile) Gawiser et al 2006a, ApJS 162, 1 Eric Gawiser (Yale, P.I.) Pieter van Dokkum (Yale, P.I.) Paulina Lira (U. Chile) Meg Urry (Yale) Martin Altmann (U. Chile) Felipe Barrientos (P.U. Catolica) Francisco Castander (IEEC-Barcelona) Daniel Christlein (U. Chile/Yale) Paolo Coppi (Yale) Marijn Franx (Leiden) Gaspar Galaz (P.U. Catolica) David Herrera (Yale) Leopoldo Infante (P.U. Catolica) Sheila Kannappan (U.T. Austin) Charles Liu (CUNY/AMNH) Sebastian Lopez (U. Chile) Danilo Marchesini (Yale) José Maza (U. Chile) Rene Méndez (U. Chile) Nelson Padilla (P.U. Catolica) Ezequiel Treister (ESO) Bill van Altena (Yale) Sukyoung Yi (Yonsei)

MUSYC (Multiwavelength Survey by Yale-Chile) Square degree comprised of four 30'x30' fields (E-CDFS, E- HDFS, SDSS , Castander’s Window ) Deep UBVRIzJHK + NB5000Å imaging (to 5  depths of U,B,V,R AB =26, K AB =23, NB5000=25) Spitzer-MIPS+IRAC/HST-ACS/GALEX/XMM/Chandra coverage in 3/4 fields Spectroscopic follow-up with VLT+VIMOS, Magellan+IMACS, Gemini+GNIRS

MUSYC: A Square-degree Survey of the Formation and Evolution of Galaxies and their Central Black Holes Science Projects: 1.Census of galaxies at z=3 (Gawiser) 2.Evolved galaxies at 2<z<3 (van Dokkum) 3.AGN demographics at 0<z<6 (Urry) 4.Properties of K-selected galaxies at z<2 (Lira, Barrientos, Infante) 5.Proper motion + color survey for white and brown dwarfs (Mendez) 6.Groups and clusters at z<1 (Christlein, Lin) 7.Recent star formation in ellipticals (Yi) 8.Public outreach at Hayden Planetarium (Liu)

Students giving MUSYC posters Paula Aguirre (PUC) "Clustering of K-selected galaxies" Harold Francke (U. Chile) "Clustering of AGN at z=3"

75% of the baryons are hydrogen At z=3, Lyman series falls in observed-frame optical Ionizing photons (>13.6eV= <912Å) do not escape  “Lyman Break” Ly  photons (10.2eV=1216Å) from recombination if stars have formed recently enough that little dust exists

Protogalaxies at z=3: TLAs LBG=Lyman Break Galaxy selected via Lyman break, blue continuum (starburst) LAE=Lyman Alpha Emitter selected via strong emission line (early stage of star formation) DRG=Distant Red Galaxy selected via Balmer break in observed NIR SMG=Sub-Millimeter Galaxy selected in sub-mm, use radio to get position DLA=Damped Lyman  Absorption system selected in absorption, N(HI)>10 20 cm -2

Origin of the Lyman break Steidel & Hamilton 1992

Origin of the Lyman break Steidel & Hamilton 1992 VRU

Lyman Break Galaxy (LBG) Steidel & Hamilton 1992

LBG in E-CDFS, R=22.8, z=3.38 strong Ly  emission (EW=60Å, SFR UV ≥350 M  /yr) numerous chemical absorption features (6 hr IMACS exposure) Ly  SiII OI/SiII CII FeII SiIV SiII CIV MUSYC

LBGs: age, stellar mass, dust, SFR Pettini 2003

Stellar winds in LBGs Pettini 2003

U B NB5000 VR Lyman  Emitter (LAE) Gawiser et al 2006b, ApJ 642, L13, astro-ph/ (MUSYC plus Caryl Gronwall, Robin Ciardullo, John Feldmeier)

BV - NB5000 selection of LAEs

LAE in E-CDFS, R=25.7, z=3.085 Ly  EW=200Å, SFR≥30 M  /yr (6 hr IMACS exposure) MUSYC Gawiser et al 2005

Rest-frame UV continuum flux of spectroscopically confirmed samples LBG LAE # obj MUSYC

UVR colors of confirmed objects Confirmed LAEConfirmed LBG

Images from HST-ACS: irregular morphology at z=3 AGN z=3.60 R=22.4 LBG z=3.37 R=24.3 LBG z=3.24 R=23.8 LAE z=3.10 R=26.1

NIR selects rest-frame Balmer break at 2<z<4 Reddy et al 2005

Distant Red Galaxies (DRG) van Dokkum et al 2005, in prep. MUSYC MUSYC van Dokkum et al 2005

Redshift distributions of 1.5<z<3.5 samples Reddy et al 2005

SMG contribution to SFRD Chapman et al 2005

z=3 universe LBGLAEDRGSMGDLA Space density ( n i / h ) 2x10 -3 Mpc -3 Adelberger et al 05 4x10 -4 Mpc -3 MUSYC 3x10 -4 Mpc -3 MUSYC 2x10 -6 Mpc -3 Chapman et al 03 ALMA SFR per object ( SFR i ) 30 M  yr -1 Shapley et al M  yr -1 MUSYC 10 M  yr -1 Hu et al M  yr -1 MUSYC 200 M  yr -1 van Dokkum et al M  yr -1 Chapman et al M  yr -1 (2 objects) Moller et al 02, Bunker et al 04 Stellar mass per object ( M *,i ) M  Shapley et al 01 M2x10 11 M  van Dokkum et al 04 MJWST Clustering length ( r 0,i / h ) 6±1 Mpc Adelberger et al 05 5±1 Mpc MUSYC 4±1 Mpc MUSYC 9±2 Mpc MUSYC Quadri et al 05 16±7 Mpc Webb et al 03 4±2 Mpc Cooke, EG et al 05 M = MUSYC, in progress

Cosmological quantities: LBGLAEDRGSMGDLA SFR density (  SFR,i = n i x SFR i ) 0.1 M  yr -1 Mpc -3 Steidel et al M  yr -1 Mpc -3 MUSYC 0.06 M  yr -1 Mpc -3 MUSYC 0.02 M  yr -1 Mpc -3 Chapman et al M  yr -1 Mpc -3 Wolfe, EG & Prochaska 03 Stellar mass density (  *,i = n i M *,i ) 10 7 M  Mpc -3 Shapley et al 01 M6x10 7 M  Mpc -3 MUSYC MJWST DM halo mass 3x10 11 M  Adelberger et al M  MUSYC 3x10 12 M  MUSYC M  MUSYC M  Cooke, EG et al 05 M = MUSYC, in progress

Three Recent Reviews Pettini 2003, “Element Abundances through the Cosmic Ages”, astro-ph/ Silk 2004, “Dark Matter and Galaxy Formation: Challenges for the Next Decade”, astro-ph/ Wolfe, Gawiser & Prochaska 2005, “The Damped Ly  Systems”, ARAA, astro-ph/

Gawiser Problem 3 is now assigned