1. MINI-WORKSHOP ON GALAXY FORMATION UC Santa Cruz, 5 Aug 04 Simulations of SN Feedback in Dwarf Disk Galaxies P. Chris Fragile Lawrence Livermore National Laboratory Collaborators: Stephen Murray, LLNL Doug Lin, UCSC

2. MINI-WORKSHOP ON GALAXY FORMATION UC Santa Cruz, 5 Aug 04 Simulations of SN Feedback in Dwarf Disk Galaxies Goals –Supernova enrichment histories of dwarf systems Building blocks for larger systems Polluters of IGM –Star-formation histories of dwarf systems Concentrated starbursts Self-regulated (distributed) star formation

3. MINI-WORKSHOP ON GALAXY FORMATION UC Santa Cruz, 5 Aug 04 Simulations of SN Feedback in Dwarf Disk Galaxies Methodology –Computational domain 30 kpc x 30 kpc x 15 kpc 256x256x128 –Galaxy potential Fixed (non-interacting) dark- matter potential –Gas distribution –Supernova input Variables: input rate and distribution Observables: mass ejection and metal ejection

4. MINI-WORKSHOP ON GALAXY FORMATION UC Santa Cruz, 5 Aug 04 Radiative Cooling Model Equilibrium cooling curve Bohringer & Hensler 1989, A&A, 215, 147; Dalgarno & McCray 1972, ARA&A, 10, 375

5. MINI-WORKSHOP ON GALAXY FORMATION UC Santa Cruz, 5 Aug 04 M d =9.1x10 9 M  M g =10 9 M  30 SNae Myr -1 Simulation = 100 Myr Model 1 Model 4 Model 3 0% distribution 30% distribution 80% distributionResults Model zz 10.0230.91 40.0280.60 30.0270.21 mass ejectionmetal ejection

6. MINI-WORKSHOP ON GALAXY FORMATION UC Santa Cruz, 5 Aug 04Results Model 1 Model zz 10.0230.91 20.0320.47 0% distribution 0% distribution, offset R d /2 Model 2 M d =9.1x10 9 M  M g =10 9 M  30 SNae Myr -1 Simulation = 100 Myr

7. MINI-WORKSHOP ON GALAXY FORMATION UC Santa Cruz, 5 Aug 04 Integrated Column Density

8. MINI-WORKSHOP ON GALAXY FORMATION UC Santa Cruz, 5 Aug 04 Implications small systems vs. BIG systems –Metal retention is poor in systems below ~10 9 M  Self-regulated star-formation vs. Bursts –Metal retention is much higher during more quiescent or distributed star formation Type I vs. Type II supernovae –“Drift” of Type I progenitors may increase expulsion of byproducts (Iron) –Preferential retention of Type II products in dwarf systems???