Stellar IMF Mass Segregation and Stellar Populations with

Stellar IMF, Mass Segregation, and Stellar Populations with the E-ELT Nate Bastian (Io. A)

Outline Stellar IMF in the Galaxy ❖ Resolved star approach ❖ Mass segregation Extreme environments ❖ Stellar IMF and cluster formation ❖ Star formation history of galaxies

IMF: Resolved Star Approach ONC - VLT/ISAAC Mtot ~ 103 Msun high mass clusters rare -> far away -> can’t get their low mass stars due to stochasticity, need IMF in many clusters over the full mass range been done for E-ELT same sensitivity as has the ONC out to ~4 kpc - 10 -20 MJupiter Muench et al. 2002

cluster distance (kpc) Mass (Msun) lower mass limit Cygnus OB 2 1. 7 ~104 < 20 MJupiter Westerlund 1 5. 5 >105 < 0. 02 Msun Arches 8 few * 104 < 0. 02 Msun While crowding will be an issue in the Trumpler 14 2. 8 ~ 104 < 20 MJupiter centers of the clusters, limits still possible cores 4 NGC 3603 outside 6. 5 the cluster few * 10 < 0. 02 Msun E-ELT: reaching into the substellar mass regime for all known Galactic young massive clusters

Need for ever deeper Observations Arches Stolte et al. 2008 Kim et al. 2006

Mass Segregation dynamical measurements of mass segregation VLT limit = 15 Msun E-ELT limit = 1 -2 Msun Gieles et al. in prep Grebel & Gallagher 2004

IMF variations in Extreme Environments Point sources: I=20 -23, K=20. 5 -23. 5 need S/N > 100 Meyer & Greissl 2005 Lamers et al. 2002

IMF Variations in Extreme Environments ❖ Arp 220 - galaxy merger ❖ SFR~240 Msun/yr ❖ 107 Msun cluster ❖ ~ 3 Myr old ❖ K ~ 22 mag Wilson et al. 2006

NGC 3256 Using clusters: detailed star-formation history and metallicity evolution for past 1 Gyr for (almost) all galaxies within 10 Mpc Trancho For nearby massive spirals - 4 -6 Gyret al. 2008 For major galaxy mergers out to ~70 Mpc

Conclusions ❖ IMF below the hydrogen burning limit for all known young massive clusters in the Galaxy ❖ Pin down mass segregation (with imaging and dynamics) ❖ Testing the IMF in extreme environments ❖ Detailed SFH and metallicity evolution of galaxies