1201.3359
MaGICC disks: matching observed galaxy relationships over a wide stellar mass range
Brook, Stinson, Gibson, Wadsley, Quinn
MaGICC: Making Galaxies in a Cosmological Context. Simulate 4 galaxies with the relation between stellar and total mass that matches disk galaxy observations. The simulations match observed relations between luminosity, rotation velocity, size, color, SFR, HI mass, baryonic mass, and metallicity. Radiation from massive stars and SNe energy regulate SF and drive outflows, balancing the interplay between gas, SF, large scale outflows, and recycling of gas in a matter that correctly scales with the mass of the galaxy. Outflows also play a key role in simulating galaxies with exponential surface brightness profiles, flat rotation curves and DM cores. Implies that large scale outflows are primary driver of the dependence of the disc galaxy properties on mass. Show that the amount of outflows invoked in model is required to meet constraints from OVI absorption observations in the circum-galactic-media of local galaxies.
* galactic outflows from SNe and stellar winds from massive stars. Outflows play a key role in gas ecology (SF, large scale outflows, recycling). DM cores, flat rotation curves, and exponential surface brightness.
* seems to be missing external supply of gas, seen in other sims.
1201.3362
Modelling injection and feedback of CR in grid-based cosmological simulations: effects on cluster outskirts
Vazza, Bruggen, Gheller, Brunetti
Use AMR code ENZO to model injection of CR particles at shocks, their advection and their dynamical feedback on thermal baryonic gas. Can track injection of CR energy, the spatial advection of CR energy, and its feedback on thermal gas in run-time. Method applied to study CR acceleration and evolution in cosmological volumes. Inclusion of CR feedback decreases the central gas density in clusters (reducing X-ray and SZ effect from cluster center), while enhancing gas density and related observables near the virial radius.
1201.3365
The cosmic web and the orientation of angular momenta
Libeskind, Hoffman, Knebe, Steinmetz, Gottlöber, Metuki, Yepes
DM cosmo simulation to examine LS orientation of haloes and substructures wrt the cosmic web. Use 1e6 haloes that span 3 orders of magnitude in mass, the orientation of the halo's spin and the orbital angular momentum of subaloes wrt the eigenvectors of the shear tensor [?] is examined. Find orbital angular momentum of subhaloes tend to align with intermediate eigenvector of velocity shear tensor for all haloes in knots, filaments and sheets. Indicates that kinematics of substructures located deep within the virialized regions of a halo is determined by its infall, which in turn is determined by the LS velocity shear, a surprising result given the virialized nature of haloes. The non-random nature of subhalo accretion is thus imprinted on the angular momentum measured at z=. Also find that haloes spin axis is aligned with the 3rd eigenvector of the velocity shear tensor in filaments and sheets [why 3rd?]: the halo spin axis points along filaments and lies in the plan of cosmic sheets.
1201.3367
A kinematic classification of the cosmic web
Hoffman,... et al
Use velocity shear tensor (rather than gravitational tidal tensor) to determine knot, sheet, filament and void. Construct shear tensor at each point and evaluate the 3 eigenvectors; classification based on the eigenvector above a threshold value.
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