exclusively in the filaments and central concentration, with halo
almost empty of gas between the filaments. Medium panel shows temperature distribution (dark blue ~ 1500K, light yellow ~5e6K). One can notice that almost all halo gas is cold and filamentary except very small amount around the center of the halo. Accreted gas can travel large distances in very short time.
Lower panel zooms onto central galaxy, to show region 1R_vir on a side (0.5R_vir from the center) and 0.5R_vir thick to show geometry and temperature of the gas accretion.
Panels on the right show the same halo at z=3.24 when it has mass M_halo=1.26e12 M_sun and was hot mode dominated. Size of the region shown is the same in units of virial radius and green particles are the one that are going to be accreted onto central galaxy in this halo in the next 190Myr, i.e. by z=3.0.
Color coding is the same for the upper panel (density), while for medium and lower panels this time temperature distribution is adjusted to be same fraction of the virial temperature as on the left panels (dark blue ~ 3000K, light yellow ~1e7K). Apparently halo is now filled with relatively dense gas even between the filaments and gas temperature inside the halo is comparable to virial temperature except at the places where filaments enter the halo. Accretion of the gas is concentrated to the central parts of the halo, while the accreted gas was part of the hot halo before it was accreted. Click on the small figure on the left to download full resolution version.