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Galaxy Evolution: last 5 years!. LBG, ERO, LRG, BZK, UGR, DRG, … .complicated! But if suspend belief in theoretical models … .then things become simpler!. CFRS Red + Blue Galaxy LFs 1996. Data: CFRS Blue+Red Galaxy LFs (Lilly et al 1996, Tresse et al 1996).
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Galaxy Evolution: last 5 years! • LBG, ERO, LRG, BZK, UGR, DRG, ….complicated! • But if suspend belief in theoretical models • ….then things become simpler!
CFRS Red + Blue Galaxy LFs 1996 Data: CFRS Blue+Red Galaxy LFs (Lilly et al 1996, Tresse et al 1996) Red +Blue lines: Bruzual+Charlot models from Metcalfe et al (1996, 2001) =9 Gyr + Salpeter for blue =2.5 Gyr + “Scalo++” for red
Faint H-band Galaxy Counts • No-evolution models fit NIR!!! • E/S0 dominate to H<20, Spirals at H>20 • Bruzual+Charlotmodel with Scalo++ IMF close to non-evolving model at H Metcalfe et al (2005)
WHDF Galaxy B-R:R-I • Hertzsprung-Russell diagram for galaxy evolution!?! • Just 2 basic galaxy evolutionary types -red and blue!
WHDF Galaxy B-R:R-I z=0.5 • Excellent agreement with simple Bruzual & Charlot models! • Exponential SFR • =9Gyr + Salpeter for Spirals • =2.5Gyr + “Scalo++” for E/SO z=3 Metcalfe et al (2001)
z≈3 Keck LBGs • z≈3 LBG LF (Steidel et al 1999) • Excellent agreement with local spiral LF plus Bruzual & Charlot =9Gyr model (Metcalfe et al 2001)
K20 Survey - Cimatti et al 2002 • No evolution models again fit well • Passive evolution models with steep IMF (eg Scalo++) also fit • See also Cowie et al (1996)
z=3 z=1 Unifying BzK, ERO, DRG…. • WHDF RIH (~BzK) • =2.5Gyr E/SO models with Scalo++ IMF again fit • BzK, ERO, DRG…. are just slowly evolving 1<z<3 E/SO
E/SO LF vs PLE - 2003 Data - COMBO-17 LF from Wolf et al 2003, Bell et al 2003 Red line - PLE E/SO model from Metcalfe et al 1996
VLT VIMOS Deep Survey Late Types: ≈2mag brightening Early Types:<0.5mag brightening
Wake et al (2007) Brown et al (2007) NDWFS Red + 2SLAQ LRGs Only passive evolution seen for early-types to z~1
Galaxy Evolution - next 5 years? • Bimodal Bruzual-Charlot models unify LBG, ERO, LRG, BZK, DRG, KGB, KFC… • High-z Universe same as low-z except spiral surface brightness is higher - no requirement for CDM mergers • Is it just phenomenology or is it physically what’s happening? • At very least a good future yardstick to measure success of semi-analytics • Next 5 years spectroscopy - to check the details - green valley etc!
Madau et al v Metcalfe et al 96 • Madau et al 96 claim HDF shows SFR peaks at z≈1 • Metcalfe et al 96 claim HDF shows SFR peaks at z>2 • Dust treatment is main difference