Abstract
AbstractWe investigate the role of supernova (SN)‐driven galactic winds in the chemical enrichment of the intracluster medium (ICM). Such outflows on galactic scales have their origin in huge star forming regions and expel metal enriched material out ofthe galaxies into their surroundings as observed, for example, in the nearby starburst galaxy NGC 253. As massive stars in OB‐associations explode sequentially, shock waves are driven into the interstellar medium (ISM) of a galaxy and merge, forming a superbubble (SB). These SBs expand in a direction perpendicular to the disk plane following the density gradient of the ISM. We use the 2D analytical approximation by Kompaneets (1960) to model the expansion of SBs in an exponentially stratified ISM. This is modified in order to describe the sequence of SN‐explosions as a time‐dependent process taking into account the main‐sequence life‐time of the SN‐progenitors and using an initial mass function to get the number of massive stars per mass interval. The evolution of the bubble in space and time is calculated analytically, from which the onset of Rayleigh‐Taylor instabilities in the shell can be determined. In its further evolution, the shell will break up and high‐metallicity gas will be ejected into the halo ofthe galaxy and even into the ICM. We derive the number of stars needed for blow‐out depending on the scale height and density ofthe ambient medium, as well as the fraction of alpha‐ and iron peak elements contained in the hot gas. Finally, the amount of metals injected by Milky Way‐type galaxies to the ICM is calculated confirming the importance ofthis enrichment process (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.