Long way to go: how outflows from large galaxies propagate through the hot halo gas

摘要: Using hydrodynamic simulations, we study the mass-loss due to supernova-driven outflows from Milky Way type disc galaxies, paying particular attention effect of extended hot halo gas. We find that total at inner radii scales roughly linearly with mass stars formed, and loading factor virial radius can be several times its value because swept up The temperature distribution outflowing material in region (similar 10 kpc) is bimodal nature, peaking 10(5) K 10(6.5) K, responsible for optical X-ray emission, respectively. contribution cold/warm gas <= 10(5.5) outflow rate within kpc approximate 0.3-0.5. warm factor, eta(3e5) (T 3 x K) related (eta(v)) as eta(v) 25 (SFR/M-circle dot yr(-1))(-0.15) a baryon fraction 0.1 starburst period 50 Myr. also discuss multiple bursts are separated by both short long periods. speed close sound halo, less than or similar 200 km s(-1). identify two `sequences' cold small scales: fast (approximate 500 s(-1)) sequence, driven unshocked free-wind; slow sequence +/- 100 conical interface superwind halo.