ARCCOS Centre of Excellence in Evolutionary Cosmology University of Central Lancashire Galaxies on a Mesh Brad Gibson Stephanie Courty, Chris Brook, Patricia Sanchez-Blazquez, Romain Teyssier

ARCCOS Centre of Excellence in Evolutionary Cosmology What We Did… parent cosmological dark matter simulation from Projet Horizon select halo randomly “zoom”-style re-simulation w/7 more levels w/baryonic physics (res = 400pc; 10 6 M  ) analyse repeat (touch on just 2 here, 1 of which was simulated with and without a polytropic equation of state ISM formalism) We may not be the first, but we’re the first with a grid code (to z=0, anyways): cf. Sommer-Larsen et al (2003); Abadi et al (2003); Governato et al (2004,2007); Robertson et al (2004); Okamoto et al (2005); Bailin et al (2005)

ARCCOS Centre of Excellence in Evolutionary Cosmology What We Found (or are finding…) Basic Characteristics Disk Kinematics Disk Chemistry Disk Edges Accretion History Future Directions Data looking for exploitation… please send suggestions.

ARCCOS Centre of Excellence in Evolutionary Cosmology Basic Characteristics B/D  0.6;  0.02; fast rotating galaxy occupying a low-spin halo

ARCCOS Centre of Excellence in Evolutionary Cosmology Comparing Star Formation Histories cf. Fenner, Murphy & Gibson (2005) semi-numerical MW model cf. Bailin et al (2005) cosmological disk (GCD+ w/Abadi et al (2003) ICs) & Brook et al (2004) semi- cosmological disk (both SPH) (Bailin) (Brook)

ARCCOS Centre of Excellence in Evolutionary Cosmology Metallicities Gas 60 kpc  0.03 dex/kpc Stars

ARCCOS Centre of Excellence in Evolutionary Cosmology Disk Kinematics: Disk Heating & the Thick Disk Quillen & Garnett (2001) Holmberg et al (2007) cf. Bailin et al (2005) cosmological disk (GCD+ w/Abadi et al (2003) ICs) & Brook et al (2004) semi-cosmological disk (both SPH) (Bailin) (Brook) Thick disk? Brook, Courty, BKG (2008)

ARCCOS Centre of Excellence in Evolutionary Cosmology Disk Kinematics The thick disk (in Bailin et al 2005 disk w/Abadi et al ICs) lags much like the spirals in Yoachim & Dalcanton (2008), but observations say…. mass-dependent lag (YD08) R thick > R thin (YD06) R thick : R thin independent of environment (Santiago & Vale 2008) Brook, Courty, BKG (2008)

ARCCOS Centre of Excellence in Evolutionary Cosmology Disk Edges: Gas Lopsided HI gas disk with truncation near R=19kpc and N HI =2x10 19 cm -2 cf. THINGS (nice agreement) Extended ionised disk cf. Bland-Hawthorn et al (1997) N(HI) N(HII) BKG et al (2008), if I have to…

ARCCOS Centre of Excellence in Evolutionary Cosmology Disk Edges: Stars / Radial Migration Sanchez-Blazquez, Courty, BKG (2008); cf Roskar et al (2008ab) Bandpass / Height Independent Breaks.. but.. radial migration does occur U-shaped age behaviour reflected in colour gradients; differential star formation in inner vs outer disk (cf. Roskar)

ARCCOS Centre of Excellence in Evolutionary Cosmology Gas Accretion History 1  0.5 M  /yr of gas flux at R=30 kpc 2  1 M  /yr of vertical gas flux at z=6 kpc cf. Fenner et al (2005) semi-numerical MW model Courty, BKG (2008); cf Dekel et al (2008), Ocvirk et al (2008)

ARCCOS Centre of Excellence in Evolutionary Cosmology Future Directions Higher resolution

ARCCOS Centre of Excellence in Evolutionary Cosmology Higher Resolution - Fully Cosmological 400pc (stars) 400pc (gas) 200pc (stars)200pc (gas)

ARCCOS Centre of Excellence in Evolutionary Cosmology Future Directions Higher resolution Scaling relations (mass, environment) ISM physics (polytropic index; blast wave parametrisation) Warp/lopsidedness characterisation “Lick” indices Dusty radiative transfer High-Velocity Clouds Radial flows SPH vs AMR comparisons w/identical initial conditions GEtool/GCD+ chemistry to RAMSES [Chemical Tagging]

ARCCOS Centre of Excellence in Evolutionary Cosmology Summary the first fully cosmological hydro-mesh disks taken to z=0? at 400pc resolution, the AMR simulations suffer from similar overmerging/overcooling/ovencentralisation as the SPH ones RAMSES is extremely efficient (recent 200pc run completed in 1 week, wall time) saturated disk heating in semi-cosmological SPH simulations not clearly replicated (yet) in cosmological simulations neutral gas disk edges truncate at comparable column densities to observed edges; ionised disks extend beyond the neutral disk, as observed radial stellar migration is observed, with surface brightness and colour profiles consistent with those observed disk “size” also growing more or less in agreement with observations gas accretion (cold and hot) is both “smooth” and “clumpy”, but growth remains more-or-less “inside-out” disk-halo circulation “flux” is >> infalling “flux” (10-50x, but highly preliminary), as observed