The first exoplanets/brown dwarfs in the Milky Way: A study of population II objects PI: M. Petr-Gotzens Total time: > 10 nights(ELT 42m)

Scientific Rationale Observations of star/star, star/brown-dwarf or star/planet systems constrain star- and planet formation theories. E.g., for star/extrasolar planet systems: Planet-host stars are metal-rich!!

Immediate objective Search for planetary mass (>1M Jup ) objects around populationII stars 1 by coronographic AO imaging (at 2micron) (figure adapted from Nakajima et al. 2005) Targeted region 30M J Central star: K=8mag Distance=100pc 10M J 30M J 70M J 1” 0.5” Expected 42m ELT performance:  K=15mag At 0.5” from central star

Immediate objective 2 by radial velocity studies Following Sozzetti et al. 2006, ApJ 649 (planets around metal-poor dwarfs) 20m/s precision in  RV  min. ~1M J  in close orbits of < 1AU Expected limit with 42m ELT: V=14.5mag Targets from Wilhelm, Beers et al (~100 stars with V= ) Charbonnel & Primas 2005 (~40 stars with V=7-11.5)

Run A: Full AO coronographic imaging (5 mas pix) T int per target = 10min (S/N ~10 for 10M >1”) Run B: Radial velocity no AO (50 mas pix) highest spectral resolution T int per target = 30min (S/N > 50) Time estimates RUN A total: 1.5n (epoch 1) + 1.5n (epoch 2) RUN B total: > 10 nights