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Conditions for supernovae driven galactic winds

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 نشر من قبل Biman Nath
 تاريخ النشر 2013
  مجال البحث فيزياء
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We point out that the commonly assumed condition for galactic outflows, that supernovae (SNe) heating is efficient in the central regions of starburst galaxies, suffers from invalid assumptions. We show that a large filling factor of hot ($ge 10^6$ K) gas is difficult to achieve through SNe heating, irrespective of the initial gas temperature and density, and of its being uniform or clumpy. We instead suggest that correlated supernovae from OB associations in molecular clouds in the central region can drive powerful outflows if the molecular surface density is $> 10^3$ M$_{odot}$ pc$^{-2}$.



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