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Make or Break: HI & Optical Views of Galaxy Disks. Dissecting and tracking disk galaxies Connecting optical and HI views back to First Light (EoR) Matching HI telescopes with counterpart optical survey engines. Matthew Bershady U. Wisconsin. Disk Galaxy Assembly. …didn’t happen this way:.
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Make or Break: HI & Optical Views of Galaxy Disks • Dissecting and tracking disk galaxies • Connecting optical and HI views back to First Light (EoR) • Matching HI telescopes with counterpart optical survey engines Matthew Bershady U. Wisconsin
Disk Galaxy Assembly …didn’t happen this way: 1<z<2 ??? today UDF • Disks are fragile destroyed in major mergers; heated in minor mergers • Dry vs wet mergers Wet mergers can make new disks; must happen early to yield old, cold disks today • Large disks today - stirred, not shaken streams not train-wrecks
Blue Cloud andRed Sequence growth and destruction • 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 e.g., Bell et al.’03,’07 Blue cloud
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 (Ha) • Measure WHI(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 SDSS M* Ha, OII, LUV Heavens et al’04 Baugh’04
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 (Ha) • Measure WHI(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 Heavens et al’04 large disks Baugh’04
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 correlations baryons processing Efficiency of processing baryons in gravitational wells
The Nearby Universe (z<0.1) Dissecting disk galaxies and establishing a stellar mass zeropoint • Ha velocity fields • Stellar velocity dispersions • Optical-mid-IR SEDs • HI synthesis maps The DiskMass Project Marc Verheijen - Kapteyn / Groningen Kyle Westfall - U. Wisconsin Rob Swaters - U. Maryland David Andersen - HIA / Victoria Thomas Martinsson - Kapetyn/Groningen
The DiskMass Project Breaking the Disk-Halo Degeneracy • 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? Maximum disk M/LK = 0.75 Sub-maxium disk M/LK = 0.22 UGC 6918 high surface-brightness disk degenerate solutions
Sample Properties: Normal Face-on Spirals from UGC 50x50 kpc: SDSS A wide range of physical size and disk morphology
Large range in SF histories: Factors of 60 in LK 10 in mR 6 in LB/LK
SparsePak FFU 82 fibers, 4.’’7 diameter 72’’ FOV l/Dl = 11,000 WIYN 3.5m (Bershady et al.’04,’05) PPak IFU 331 fibers, 2.’’7 diam. 75’’ FOV l/Dl = 8000 Calar Alto 3.5m (Verheijen et al.’05) Optical Survey Engines Customized integral field units… gas stars
Connecting mass and fuel to consumption Radio synthesis maps (Westerbork + VLA) Baryon reservoir Halo mass at large radii
Connecting mass and fuel to consumption High-resolution 2D optical kinematics: stars + gas SFR: Ha + Spitzer
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 globular clusters
At z=0.5, the red sequence is well-formed MS0451: z=0.54, s=1354 km/s, Lx=40e44 ergs/s WIYN Long-Term Variability Survey Crawford et al. 2006, 2008
At z=0.9, the blue cloud dominates. . . even in rich clusters CL1604: z=0.9, s=982 km/s, Lx=2e44 ergs/s WIYN Long-Term Variability Survey Crawford et al. 2006, 2008
HI View: State of the Art: Verheijen et al. 2007 (van Gorkum) 45’ z=0.2 Red sequence Blue cloud NB: 200h of 1000h total to come! Westerbork
HI View: State of the Art A963 - Westerbork • Solid detections for 42 sources in 2 x 0.4 deg2 fields • expect 200 sources in 1000h • Limited spatially-resolved kinematic information • Ha offers detailed kinematic supplement + SFR map • t=80 min, 3.5m telescope (CA) • 16x16 array of 1” fibers (PMAS) A2192 (z=0.19) - VLA MHI=7x109 Msun Verheijen & Dwarakanath ‘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 • Ha 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 spectrograph • 15 units + 15 sky fibers, 25’ patrol field • 2” x 3” arcsec units: 20 square microlenses (0.52” sampling) • 11000<l/dl< 39000, 370-950 nm range Eisenhauer et al.’03 Larkin et al.’06 McGregor et al. ‘99 Flores et al.’04
Multiplex at high-z: Science: emission-line kinematics of distant galaxies. Flores et al.’06 VLT / GIRAFFE This is a powerful instrument . . . . . . But note: isovels heavily smoothed. Enough sampling?
Finding First Light z = 12.1 9 .2 7.6 H I brightness temperature: Reionization • 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. Furlanetto et al. Simulations Ly In the J band 2’x2’ 8m tel Barton et al. ‘04
Robert Stobie Spectrograph (RSS) @ prime focus Wisconsin-Rutgers-SAAOOptical: Nordsieck, Williams, O’Donoghue NIR: Sheinis, Wolf, Bershady & Nordsieck SALT: Southern African Large Telescope
SALT: Tilted, rotating Arecibo Payload RSS Tracker Bream Primary Mirror spherical aberration corrector Concrete Pier
Vis-gratings gratings filters Vis-Camera F-P Nordsieck Pre-Dewar RSS: Optical + NIR beams Sheinis Dewar Camera Vis F-P’s Pol-BS Williams pupil doublet
RSS Optical layout/Components pupil Pre-Dewar F-P gratings filters doublet Detector Dichroic-BS Dewar Camera collimator Slit
Emission-line Sensitivies SALT RSS Visibile and NIR beam, 1 arcsec2 aperture Ha from 0<z<1.75 to 0.1 Mo/yr • Star-formation rates • Nebular abundances Ha/[NII], [OIII]/H • Redenning Ha/Hb • Lya from 2.6<z<12 to 1 Mo/yr • First Light / EoR 5s, 1h, l/dl=4000, 1 arcsec2
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 & abundances • z<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 Light • Redshifts to z=10 $0.5-1M $10-15M same instrument $1G $10M