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Enhanced SFR in galaxy pairs and mergers from IR-bright galaxies in GEMS. Aday Robaina Rapisarda (Yes, two surnames) Lago di Como, Italy 28-3-2007. Looking for mergers (nothing to do with the talk title). In the local universe, everybody agrees on their classifications. Random one.
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Enhanced SFR in galaxy pairs and mergers from IR-bright galaxies in GEMS Aday Robaina Rapisarda (Yes, two surnames) Lago di Como, Italy 28-3-2007
Looking for mergers (nothing to do with the talk title) • In the local universe, everybody agrees on their classifications. Random one Antennae M101
Automatic Classifiers: Concentration and Asymmetry Early types (0<A<0.5) Late types (0.35<A<1.1)
Strange guys A>0.7 • Automated classifiers designed to imitate human eye • Tested on close galaxy samples (Fried catalogue) • Work reasonably well on isolated galaxies, but…
What about this? I don’t know and they don´t explain
Enhanced Star Formation in Interactions (Approaching the end of the talk) Local universe High redshift Lambas et al. 2003 Lin et al. 2006
GEMS Results • New statistical approach (no need for 2-point correlation function) • Clear enhancement in close pairs and mergers • Averaged SFR in pairs defined • Error bars minimized due to the new approach (not too bad compared with spectroscopic surveys) • Results will improve with the STAGES dataset
Merger Fraction in 24μm Sample • Merger fraction clearly increases with TIR luminosity • 20% TIR luminosity in strong mergers • 30% TIR luminosity in interactions • Mergers 2.09 times brighter than “normal” pairs Rapid decline in the CSFH is not due to a merger evolution (more restrictive results than in Bell et al. 2005)
Blue-Rose-Ring Galaxy • LIRG • Starburst • X-ray • Spectacular Morphology