THE ACCRETION OF FUEL AT THE DISK-HALO INTERFACE：（燃料的吸积DISK-HALO接口）.pdfVIP

The Role of Disk-Halo Interaction in Galaxy Evolution: Outflow vs Infall? Editor EAS Publications Series, Vol. ?, 2009 9 0 0 2 THE ACCRETION OF FUEL AT THE DISK-HALO INTERFACE l u M.E. Putman 1, J.E.G. Peek2 and F. Heitsch3 J 6 ] Abstract. We discuss the support for the cooling of gas directly at the A disk-halo interface as a mechanism to continually fuel a galaxy. This G may be an important reservoir as there is not enough cold gas observed . in galaxy halos and simulations indicate the existing cold clouds will be h rapidly destroyed as they move through the surrounding halo medium. p We show possible evidence for a net infall of the WIM layer in the - Milky Way, simulation results showing the recooling of warm clouds at o r the disk-halo interface, and GALFA HI data of small, cold HI clouds t that could represent this recooling. s a [ 1 Introduction 1 v 3 A typical spiral galaxy requires a source of ongoing incoming fuel to maintain 2 its star formation and explain its stellar metallicity distribution (Chiappini et 0 al. 2001; Sommer-Larsen et al. 2003). The Milky Way is a specific example 1. of a galaxy that will run out of star formation fuel within a few Gyrs without an 7 ongoing source. In addition, the fact that the amount of HI in the universe appears 0 to remain flat since z = 3, but the stellar content continues to increase, indicates 9 0 the HI must somehow be continually replenished (e.g., Prochaska Wolfe 2009; : Putman et al. 2009; Hopkins et al. 2008). v Any external star formation fuel must enter the galaxy through its halo, and be i X integrated into the disk through the disk-halo interface. The primary