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تسجيل مستخدم جديدEvolution of M82-like starburst winds revisited: 3D radiative cooling hydrodynamical simulations
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In this study we present three-dimensional radiative cooling hydrodynamical simulations of galactic winds generated particularly in M82-like starburst galaxies. We have considered intermittent winds induced by SNe explosions within super star clusters randomly distributed in the central region of the galaxy and were able to reproduce the observed M82 wind conditions with its complex morphological outflow structure. We have found that the environmental conditions in the disk in nearly recent past are crucial to determine whether the wind will develop a large scale rich filamentary structure, as in M82 wind, or not. Also, the numerical evolution of the SN ejecta have allowed us to obtain the abundance distribution over the first 3 kpc extension of the wind and we have found that the SNe explosions change significantly the metallicity only of the hot, low-density wind component. Moreover, we have found that the SN-driven wind transports to outside the disk large amounts of energy, momentum and gas, but the more massive high-density component reaches only intermediate altitudes smaller than 1.5 kpc. Therefore, no significant amounts of gas mass are lost to the IGM and the mass evolution of the galaxy is not much affected by the starburst events occurring in the nuclear region.
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