US SKA Nov’08

Make or Break: HI & Optical Views of Galaxy

Disks

Matthew BershadyU. Wisconsin

Dissecting and tracking disk galaxies

Connecting optical and HI views back to First Light (EoR)

Matching HI telescopes with counterpart optical survey engines

US SKA Nov’08

Disk Galaxy Assembly

1<z<2 ??? today

Disks are fragiledestroyed in major mergers; heated in minor mergers

Dry vs wet mergersWet mergers can make new disks; must happen early to yield old, cold disks today

Large disks today - stirred, not shaken streams not train-wrecks

…didn’t happen this way:

UDF

US SKA Nov’08

Blue Cloud and Red Sequence

Some galaxies evolve from blue cloud to form the red sequence.

Most stars are made in the blue cloud but end up in the red sequence.

Identify which are stirred, which are shaken:

Tag environment For those that are stirred:

Monitor smooth & continuous…

accretion growth star-formation

gas consumption

Red sequence

Blue cloud

e.g., Bell et al.’03,’07

growth and destruction

US SKA Nov’08

Connect Optical and HI Views

Are these two trends self-consistent?

Confirm SFR with a single, direct measure from z=0 to z=1 and higher (H)

Measure HI(z) and HI mass-function directly

Determine SFR as function of both dynamical and HI mass

Identify the individual galaxies, e.g., at the knee of the HI mass-functionBaugh’04

Heavens et al’04

SDSS M*

H, OII, LUV

US SKA Nov’08

Go beyond the co-moving integral

Are these two trends self-consistent?

Confirm SFR with a single, direct measure from z=0 to z=1 and higher (H)

Measure HI(z) and HI mass-function directly

Determine SFR as function of both dynamical and HI mass

Identify the individual galaxies, e.g., at the knee of the HI mass-function

large disks

Baugh’04

Heavens et al’04

US SKA Nov’08

Trace Key Observables in the Blue Cloud

Dynamical mass HI mass (+molecular) Star-formation rate (SFR) Stellar mass (dynamically calibrated) Abundances

Dynamical mass - baryonic mass - metallicity

correlationsEfficiency of processing baryons in gravitational wells

pro

cess

ing

baryons

US SKA Nov’08

The Nearby Universe (z<0.1)

H velocity fields Stellar velocity

dispersions Optical-mid-IR SEDs HI synthesis maps

Marc Verheijen - Kapteyn / GroningenKyle Westfall - U. Wisconsin Rob Swaters - U. Maryland David Andersen - HIA / VictoriaThomas Martinsson - Kapetyn/Groningen

The DiskMass Project

Dissecting disk galaxies and establishing a stellar mass zeropoint

US SKA Nov’08

The DiskMass Project

What are the shapes of dark halos?

How massive are spiral disks?

Are they maximal? What’s the stellar mass-to-

light ratio (M/L) in disks?

Breaking the Disk-Halo Degeneracy

Maximum disk M/LK = 0.75

degenerate solutions

Sub-maxium disk M/LK = 0.22

UGC 6918 high surface-brightness disk

US SKA Nov’08

Sample Properties:

50x50 kpc: SDSS

A wide range of physical size and disk morphology

Normal Face-on Spirals from UGC

US SKA Nov’08

Large range in SF histories:

Factors of 60 in LK

10 in R

6 in LB/LK

US SKA Nov’08

Optical Survey Engines

SparsePak FFU 82 fibers, 4.’’7

diameter 72’’ FOV = 11,000 WIYN 3.5m (Bershady et al.’04,’05)

PPak IFU 331 fibers, 2.’’7 diam. 75’’ FOV = 8000 Calar Alto 3.5m (Verheijen et al.’05)

Customized integral field units…

gas

stars

US SKA Nov’08

Connecting mass and fuel to consumption

Radio synthesis maps (Westerbork + VLA)

Baryon reservoir Halo mass at large radii

US SKA Nov’08

SFR: H + Spitzer High-resolution 2D optical kinematics: stars + gas

Connecting mass and fuel to consumption

US SKA Nov’08

Mapping the Cosmic History of Disks

• Track blue cloud in a range of environments across look-back time

Clusters are nodes in the cosmic web Large volumes around clusters probe

the largest dynamic range in environments

• Find the primeval disks at “First Light” – driving part of the Epoch of Re-ionization (EoR)

0<z<1.5

7<z<12 globularclusters

US SKA Nov’08

At z=0.5, the red sequence is well-formed

MS0451: z=0.54, =1354 km/s, Lx=40e44 ergs/s

WIYN Long-Term Variability SurveyCrawford et al. 2006, 2008

US SKA Nov’08

At z=0.9, the blue cloud dominates

. . . even in rich clustersCL1604: z=0.9, =982 km/s, Lx=2e44 ergs/s

WIYN Long-Term Variability SurveyCrawford et al. 2006, 2008

US SKA Nov’08

HI View: State of the Art:

Verheijen et al. 2007 (van Gorkum)

NB: 200h of 1000h total to come!

Blue cloud

Red sequence

z=0.2

Westerbork

45’

US SKA Nov’08

HI View: State of the Art

Solid detections for 42 sources in 2 x 0.4 deg2 fields

expect 200 sources in 1000h

Limited spatially-resolved kinematic information

H offers detailed kinematic supplement + SFR map

t=80 min, 3.5m telescope (CA)

16x16 array of 1” fibers (PMAS)

A963 - Westerbork

A2192 (z=0.19) - VLA MHI=7x109 Msun

Verheijen & Dwarakanath ‘08

US SKA Nov’08

Optical Follow-up at z>0.2

Scale 4m-class IFU observations to 8m-class telescopes comparable S/N in t=10h, 10 times angular

resolution, twice the luminosity Stellar kinematics out z=0.2 H out to z=1 w/ NIR and AO

Best example: VLT / Sinfoni also Keck / OSIRIS and Gemini / NIFS

Multi-object IFU ? Only example in optical: VLT / FLAMES-GIRAFFE

Fiber+lenslet coupled spectrograph15 units + 15 sky fibers, 25’ patrol field2” x 3” arcsec units: 20 square microlenses (0.52” sampling)11000<< 39000, 370-950 nm range

Flores et al.’04

Eisenhauer et al.’03Larkin et al.’06McGregor et al. ‘99

US SKA Nov’08

Multiplex at high-z:

VLT / GIRAFFE

This is a powerful instrument . . . . . . But note: isovels heavily smoothed.Enough sampling?

Science: emission-line kinematics of distant galaxies.

Flores et al.’06

US SKA Nov’08

Finding First Light

Science Goal: Discover how rapidly the first galaxies form.

When is reionization complete?

The frontier is z>7. The achievable flux limit for SALT is about z=10 (Ly @1.35 m)

Instrument Requirements:

Fabry-Perot imaging: =2500 z=8: we expect > 30 sources in 12

hours z=9-10: expect ~30 sources in 53-

1600 hours Simultaneous optical FP to cull

interlopers (redshifted [OII]3727 if NIR-line is H).

Follow-up optical-NIR MOS at >4000:

eliminate remaining interlopers (split [OII]3727 doublet);

determine kinematics to make dynamical mass estimates;

constrain winds and outflows.

H Ibrightnesstemperature:Reionization

z = 12.1 9 .2 7.6

LyIn theJ band

Barton et al. ‘04

Furlanetto et al.

Sim

ulat

ions

2’x2’8m tel

US SKA Nov’08

Robert Stobie Spectrograph (RSS)@ prime focus

Wisconsin-Rutgers-SAAOOptical: Nordsieck, Williams, O’Donoghue NIR: Sheinis, Wolf, Bershady & Nordsieck

SALT: Southern African Large Telescope

US SKA Nov’08

SALT: Tilted, rotating Arecibo

Tracker

Bream

Payload

Primary Mirror

Concrete Pier

RSS

spherical aberrationcorrector

US SKA Nov’08

RSS: Optical + NIR beams

Dewar

Pre-Dewar

Camera

F-P

doublet

gratings

pupil

filters

Pol-BS

Vis-Camera

Vis F-P’s

Vis-gratings

Nordsieck

Sheinis

Williams

US SKA Nov’08

Dewar

Pre-Dewar

Camera

F-P

doublet

collimatorSlit

gratings

Detector

pupil

filters

Dichroic-BS

RSS Optical layout/Components

US SKA Nov’08

Emission-line Sensitivies

SALT RSS Visibile and NIR beam, 1 arcsec2 aperture

H from 0<z<1.75 to 0.1 Mo/yr

Star-formation rates Nebular abundances H/[NII], [OIII]/HRedenning H/H

Lyfrom 2.6<z<12 to 1 Mo/yr

First Light / EoR5, 1h=4000, 1 arcsec2

US SKA Nov’08

Future Possibilities…toward SKA

HI surveys of disk galaxies Arecibo, pointed (GASS++): z~0.3 Westerbork, EVLA, blind: z~0.2-0.4 MeerKAT, BigKAT, ASKAP, blind: z~0.3-0.6 EoR ???

3D Optical Spectroscopic Follow-up of HI surveys

Spatially resolved ionized-gas kinematics & abundancesz<0.2-0.3: minor investment in existing 4m-

class facilities, z>0.3: major investment in new 8m-

class instrumentation Stellar kinematics

z<0.2-0.3: major investment in new 8m-class instrumentation

z>0.3: 30m-class optical telescope + spectrograph

2D Optical Discovery of First LightRedshifts to z=10

same instrument

$0.5-1M

$10-15M

$1G

$10M